WorldWideScience

Sample records for cost-effectiveness issues uncertainties

  1. Cost-effective conservation of an endangered frog under uncertainty.

    Science.gov (United States)

    Rose, Lucy E; Heard, Geoffrey W; Chee, Yung En; Wintle, Brendan A

    2016-04-01

    How should managers choose among conservation options when resources are scarce and there is uncertainty regarding the effectiveness of actions? Well-developed tools exist for prioritizing areas for one-time and binary actions (e.g., protect vs. not protect), but methods for prioritizing incremental or ongoing actions (such as habitat creation and maintenance) remain uncommon. We devised an approach that combines metapopulation viability and cost-effectiveness analyses to select among alternative conservation actions while accounting for uncertainty. In our study, cost-effectiveness is the ratio between the benefit of an action and its economic cost, where benefit is the change in metapopulation viability. We applied the approach to the case of the endangered growling grass frog (Litoria raniformis), which is threatened by urban development. We extended a Bayesian model to predict metapopulation viability under 9 urbanization and management scenarios and incorporated the full probability distribution of possible outcomes for each scenario into the cost-effectiveness analysis. This allowed us to discern between cost-effective alternatives that were robust to uncertainty and those with a relatively high risk of failure. We found a relatively high risk of extinction following urbanization if the only action was reservation of core habitat; habitat creation actions performed better than enhancement actions; and cost-effectiveness ranking changed depending on the consideration of uncertainty. Our results suggest that creation and maintenance of wetlands dedicated to L. raniformis is the only cost-effective action likely to result in a sufficiently low risk of extinction. To our knowledge we are the first study to use Bayesian metapopulation viability analysis to explicitly incorporate parametric and demographic uncertainty into a cost-effective evaluation of conservation actions. The approach offers guidance to decision makers aiming to achieve cost-effective

  2. Uncertainty and sampling issues in tank characterization

    International Nuclear Information System (INIS)

    Liebetrau, A.M.; Pulsipher, B.A.; Kashporenko, D.M.

    1997-06-01

    A defensible characterization strategy must recognize that uncertainties are inherent in any measurement or estimate of interest and must employ statistical methods for quantifying and managing those uncertainties. Estimates of risk and therefore key decisions must incorporate knowledge about uncertainty. This report focuses statistical methods that should be employed to ensure confident decision making and appropriate management of uncertainty. Sampling is a major source of uncertainty that deserves special consideration in the tank characterization strategy. The question of whether sampling will ever provide the reliable information needed to resolve safety issues is explored. The issue of sample representativeness must be resolved before sample information is reliable. Representativeness is a relative term but can be defined in terms of bias and precision. Currently, precision can be quantified and managed through an effective sampling and statistical analysis program. Quantifying bias is more difficult and is not being addressed under the current sampling strategies. Bias could be bounded by (1) employing new sampling methods that can obtain samples from other areas in the tanks, (2) putting in new risers on some worst case tanks and comparing the results from existing risers with new risers, or (3) sampling tanks through risers under which no disturbance or activity has previously occurred. With some bound on bias and estimates of precision, various sampling strategies could be determined and shown to be either cost-effective or infeasible

  3. Limitations of acceptability curves for presenting uncertainty in cost-effectiveness analysis

    NARCIS (Netherlands)

    Groot Koerkamp, Bas; Hunink, M. G. Myriam; Stijnen, Theo; Hammitt, James K.; Kuntz, Karen M.; Weinstein, Milton C.

    2007-01-01

    Clinical journals increasingly illustrate uncertainty about the cost and effect of health care interventions using cost-effectiveness acceptability curves (CEACs). CEACs present the probability that each competing alternative is optimal for a range of values of the cost-effectiveness threshold. The

  4. Uncertainty Communication. Issues and good practice

    International Nuclear Information System (INIS)

    Kloprogge, P.; Van der Sluijs, J.; Wardekker, A.

    2007-12-01

    In 2003 the Netherlands Environmental Assessment Agency (MNP) published the RIVM/MNP Guidance for Uncertainty Assessment and Communication. The Guidance assists in dealing with uncertainty in environmental assessments. Dealing with uncertainty is essential because assessment results regarding complex environmental issues are of limited value if the uncertainties have not been taken into account adequately. A careful analysis of uncertainties in an environmental assessment is required, but even more important is the effective communication of these uncertainties in the presentation of assessment results. The Guidance yields rich and differentiated insights in uncertainty, but the relevance of this uncertainty information may vary across audiences and uses of assessment results. Therefore, the reporting of uncertainties is one of the six key issues that is addressed in the Guidance. In practice, users of the Guidance felt a need for more practical assistance in the reporting of uncertainty information. This report explores the issue of uncertainty communication in more detail, and contains more detailed guidance on the communication of uncertainty. In order to make this a 'stand alone' document several questions that are mentioned in the detailed Guidance have been repeated here. This document thus has some overlap with the detailed Guidance. Part 1 gives a general introduction to the issue of communicating uncertainty information. It offers guidelines for (fine)tuning the communication to the intended audiences and context of a report, discusses how readers of a report tend to handle uncertainty information, and ends with a list of criteria that uncertainty communication needs to meet to increase its effectiveness. Part 2 helps writers to analyze the context in which communication takes place, and helps to map the audiences, and their information needs. It further helps to reflect upon anticipated uses and possible impacts of the uncertainty information on the

  5. Introducing nonpoint source transferable quotas in nitrogen trading: The effects of transaction costs and uncertainty.

    Science.gov (United States)

    Zhou, Xiuru; Ye, Weili; Zhang, Bing

    2016-03-01

    Transaction costs and uncertainty are considered to be significant obstacles in the emissions trading market, especially for including nonpoint source in water quality trading. This study develops a nonlinear programming model to simulate how uncertainty and transaction costs affect the performance of point/nonpoint source (PS/NPS) water quality trading in the Lake Tai watershed, China. The results demonstrate that PS/NPS water quality trading is a highly cost-effective instrument for emissions abatement in the Lake Tai watershed, which can save 89.33% on pollution abatement costs compared to trading only between nonpoint sources. However, uncertainty can significantly reduce the cost-effectiveness by reducing trading volume. In addition, transaction costs from bargaining and decision making raise total pollution abatement costs directly and cause the offset system to deviate from the optimal state. While proper investment in monitoring and measuring of nonpoint emissions can decrease uncertainty and save on the total abatement costs. Finally, we show that the dispersed ownership of China's farmland will bring high uncertainty and transaction costs into the PS/NPS offset system, even if the pollution abatement cost is lower than for point sources. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Uncertainty in decision models analyzing cost-effectiveness : The joint distribution of incremental costs and effectiveness evaluated with a nonparametric bootstrap method

    NARCIS (Netherlands)

    Hunink, Maria; Bult, J.R.; De Vries, J; Weinstein, MC

    1998-01-01

    Purpose. To illustrate the use of a nonparametric bootstrap method in the evaluation of uncertainty in decision models analyzing cost-effectiveness. Methods. The authors reevaluated a previously published cost-effectiveness analysis that used a Markov model comparing initial percutaneous

  7. Better informing decision making with multiple outcomes cost-effectiveness analysis under uncertainty in cost-disutility space.

    Science.gov (United States)

    McCaffrey, Nikki; Agar, Meera; Harlum, Janeane; Karnon, Jonathon; Currow, David; Eckermann, Simon

    2015-01-01

    Comparing multiple, diverse outcomes with cost-effectiveness analysis (CEA) is important, yet challenging in areas like palliative care where domains are unamenable to integration with survival. Generic multi-attribute utility values exclude important domains and non-health outcomes, while partial analyses-where outcomes are considered separately, with their joint relationship under uncertainty ignored-lead to incorrect inference regarding preferred strategies. The objective of this paper is to consider whether such decision making can be better informed with alternative presentation and summary measures, extending methods previously shown to have advantages in multiple strategy comparison. Multiple outcomes CEA of a home-based palliative care model (PEACH) relative to usual care is undertaken in cost disutility (CDU) space and compared with analysis on the cost-effectiveness plane. Summary measures developed for comparing strategies across potential threshold values for multiple outcomes include: expected net loss (ENL) planes quantifying differences in expected net benefit; the ENL contour identifying preferred strategies minimising ENL and their expected value of perfect information; and cost-effectiveness acceptability planes showing probability of strategies minimising ENL. Conventional analysis suggests PEACH is cost-effective when the threshold value per additional day at home (1) exceeds $1,068 or dominated by usual care when only the proportion of home deaths is considered. In contrast, neither alternative dominate in CDU space where cost and outcomes are jointly considered, with the optimal strategy depending on threshold values. For example, PEACH minimises ENL when 1=$2,000 and 2=$2,000 (threshold value for dying at home), with a 51.6% chance of PEACH being cost-effective. Comparison in CDU space and associated summary measures have distinct advantages to multiple domain comparisons, aiding transparent and robust joint comparison of costs and multiple

  8. Better Informing Decision Making with Multiple Outcomes Cost-Effectiveness Analysis under Uncertainty in Cost-Disutility Space

    Science.gov (United States)

    McCaffrey, Nikki; Agar, Meera; Harlum, Janeane; Karnon, Jonathon; Currow, David; Eckermann, Simon

    2015-01-01

    Introduction Comparing multiple, diverse outcomes with cost-effectiveness analysis (CEA) is important, yet challenging in areas like palliative care where domains are unamenable to integration with survival. Generic multi-attribute utility values exclude important domains and non-health outcomes, while partial analyses—where outcomes are considered separately, with their joint relationship under uncertainty ignored—lead to incorrect inference regarding preferred strategies. Objective The objective of this paper is to consider whether such decision making can be better informed with alternative presentation and summary measures, extending methods previously shown to have advantages in multiple strategy comparison. Methods Multiple outcomes CEA of a home-based palliative care model (PEACH) relative to usual care is undertaken in cost disutility (CDU) space and compared with analysis on the cost-effectiveness plane. Summary measures developed for comparing strategies across potential threshold values for multiple outcomes include: expected net loss (ENL) planes quantifying differences in expected net benefit; the ENL contour identifying preferred strategies minimising ENL and their expected value of perfect information; and cost-effectiveness acceptability planes showing probability of strategies minimising ENL. Results Conventional analysis suggests PEACH is cost-effective when the threshold value per additional day at home ( 1) exceeds $1,068 or dominated by usual care when only the proportion of home deaths is considered. In contrast, neither alternative dominate in CDU space where cost and outcomes are jointly considered, with the optimal strategy depending on threshold values. For example, PEACH minimises ENL when 1=$2,000 and 2=$2,000 (threshold value for dying at home), with a 51.6% chance of PEACH being cost-effective. Conclusion Comparison in CDU space and associated summary measures have distinct advantages to multiple domain comparisons, aiding

  9. Using cost-benefit concepts in design floods improves communication of uncertainty

    Science.gov (United States)

    Ganora, Daniele; Botto, Anna; Laio, Francesco; Claps, Pierluigi

    2017-04-01

    Flood frequency analysis, i.e. the study of the relationships between the magnitude and the rarity of high flows in a river, is the usual procedure adopted to assess flood hazard, preliminary to the plan/design of flood protection measures. It grounds on the fit of a probability distribution to the peak discharge values recorded in gauging stations and the final estimates over a region are thus affected by uncertainty, due to the limited sample availability and of the possible alternatives in terms of the probabilistic model and the parameter estimation methods used. In the last decade, the scientific community dealt with this issue by developing a number of methods to quantify such uncertainty components. Usually, uncertainty is visually represented through confidence bands, which are easy to understand, but are not yet demonstrated to be useful for design purposes: they usually disorient decision makers, as the design flood is no longer univocally defined, making the decision process undetermined. These considerations motivated the development of the uncertainty-compliant design flood estimator (UNCODE) procedure (Botto et al., 2014) that allows one to select meaningful flood design values accounting for the associated uncertainty by considering additional constraints based on cost-benefit criteria. This method suggests an explicit multiplication factor that corrects the traditional (without uncertainty) design flood estimates to incorporate the effects of uncertainty in the estimate at the same safety level. Even though the UNCODE method was developed for design purposes, it can represent a powerful and robust tool to help clarifying the effects of the uncertainty in statistical estimation. As the process produces increased design flood estimates, this outcome demonstrates how uncertainty leads to more expensive flood protection measures, or insufficiency of current defenses. Moreover, the UNCODE approach can be used to assess the "value" of data, as the costs

  10. Marketable pollution permits with uncertainty and transaction costs

    International Nuclear Information System (INIS)

    Montero, Juan-Pablo

    1998-01-01

    Increasing interest in the use of marketable permits for pollution control has become evident in recent years. Concern regarding their performance still remains because empirical evidence has shown transaction costs and uncertainty to be significant in past and existing marketable permits programs. In this paper we develop theoretical and numerical models that include transaction costs and uncertainty (in trade approval) to show their effects on market performance (i.e., equilibrium price of permits and trading volume) and aggregate control costs. We also show that in the presence of transaction costs and uncertainty the initial allocation of permits may not be neutral in terms of efficiency. Furthermore, using a numerical model for a hypothetical NO x trading program in which participants have discrete control technology choices, we find that aggregate control costs and the equilibrium price of permits are sensitive to the initial allocation of permits, even for constant marginal transaction costs and certainty

  11. Risk aversion and uncertainty in cost-effectiveness analysis: the expected-utility, moment-generating function approach.

    Science.gov (United States)

    Elbasha, Elamin H

    2005-05-01

    The availability of patient-level data from clinical trials has spurred a lot of interest in developing methods for quantifying and presenting uncertainty in cost-effectiveness analysis (CEA). Although the majority has focused on developing methods for using sample data to estimate a confidence interval for an incremental cost-effectiveness ratio (ICER), a small strand of the literature has emphasized the importance of incorporating risk preferences and the trade-off between the mean and the variance of returns to investment in health and medicine (mean-variance analysis). This paper shows how the exponential utility-moment-generating function approach is a natural extension to this branch of the literature for modelling choices from healthcare interventions with uncertain costs and effects. The paper assumes an exponential utility function, which implies constant absolute risk aversion, and is based on the fact that the expected value of this function results in a convenient expression that depends only on the moment-generating function of the random variables. The mean-variance approach is shown to be a special case of this more general framework. The paper characterizes the solution to the resource allocation problem using standard optimization techniques and derives the summary measure researchers need to estimate for each programme, when the assumption of risk neutrality does not hold, and compares it to the standard incremental cost-effectiveness ratio. The importance of choosing the correct distribution of costs and effects and the issues related to estimation of the parameters of the distribution are also discussed. An empirical example to illustrate the methods and concepts is provided. Copyright 2004 John Wiley & Sons, Ltd

  12. Cost uncertainty for different levels of technology maturity

    International Nuclear Information System (INIS)

    DeMuth, S.F.; Franklin, A.L.

    1996-01-01

    It is difficult at best to apply a single methodology for estimating cost uncertainties related to technologies of differing maturity. While highly mature technologies may have significant performance and manufacturing cost data available, less well developed technologies may be defined in only conceptual terms. Regardless of the degree of technical maturity, often a cost estimate relating to application of the technology may be required to justify continued funding for development. Yet, a cost estimate without its associated uncertainty lacks the information required to assess the economic risk. For this reason, it is important for the developer to provide some type of uncertainty along with a cost estimate. This study demonstrates how different methodologies for estimating uncertainties can be applied to cost estimates for technologies of different maturities. For a less well developed technology an uncertainty analysis of the cost estimate can be based on a sensitivity analysis; whereas, an uncertainty analysis of the cost estimate for a well developed technology can be based on an error propagation technique from classical statistics. It was decided to demonstrate these uncertainty estimation techniques with (1) an investigation of the additional cost of remediation due to beyond baseline, nearly complete, waste heel retrieval from underground storage tanks (USTs) at Hanford; and (2) the cost related to the use of crystalline silico-titanate (CST) rather than the baseline CS100 ion exchange resin for cesium separation from UST waste at Hanford

  13. A probabilistic approach to cost and duration uncertainties in environmental decisions

    International Nuclear Information System (INIS)

    Boak, D.M.; Painton, L.

    1996-01-01

    Sandia National Laboratories has developed a method for analyzing life-cycle costs using probabilistic cost forecasting and utility theory to determine the most cost-effective alternatives for safe interim storage of radioactive materials. The method explicitly incorporates uncertainties in cost and storage duration by (1) treating uncertain component costs as random variables represented by probability distributions, (2) treating uncertain durations as chance nodes in a decision tree, and (3) using stochastic simulation tools to generate life-cycle cost forecasts for each storage alternative. The method applies utility functions to the forecasted costs to incorporate the decision maker's risk preferences, making it possible to compare alternatives on the basis of both cost and cost utility. Finally, the method is used to help identify key contributors to the uncertainty in forecasted costs to focus efforts aimed at reducing cost uncertainties. Where significant cost and duration uncertainties exist, and where programmatic decisions must be made despite these uncertainties, probabilistic forecasting techniques can yield important insights into decision alternatives, especially when used as part of a larger decision analysis framework and when properly balanced with deterministic analyses. Although the method is built around an interim storage example, it is potentially applicable to many other environmental decision problems

  14. Measurement Issues for Energy Efficient Commercial Buildings: Productivity and Performance Uncertainties

    Energy Technology Data Exchange (ETDEWEB)

    Jones, D.W.

    2002-05-16

    buildings. Commercially available data bases exist that, if supplemented with engineering survey for equipment and materials use, could be analyzed statistically with a hedonic price model for the valuation of both the energy-saving and productivity effects of building technologies. Uncertainties about technology performance can cause investors to delay deploying new technologies. This behavior is explained by the ''investment under uncertainty'' literature. This literature suggests that under conditions of irrecoverable (''sunk'') costs, uncertain outcomes, and the ability to defer deployment, decision makers focus on potential losses and demand risk premiums and a few support the notion of focusing on losses, the so-called ''bad news principle.'' We describe a series of approaches to isolating buyer perceptions of uncertainty and means for reducing uncertainty.

  15. Addressing Uncertainties in Cost Estimates for Decommissioning Nuclear Facilities

    International Nuclear Information System (INIS)

    Benjamin, Serge; Descures, Sylvain; Du Pasquier, Louis; Francois, Patrice; Buonarotti, Stefano; Mariotti, Giovanni; Tarakonov, Jurij; Daniska, Vladimir; Bergh, Niklas; Carroll, Simon; AaSTRoeM, Annika; Cato, Anna; De La Gardie, Fredrik; Haenggi, Hannes; Rodriguez, Jose; Laird, Alastair; Ridpath, Andy; La Guardia, Thomas; O'Sullivan, Patrick; ); Weber, Inge; )

    2017-01-01

    The cost estimation process of decommissioning nuclear facilities has continued to evolve in recent years, with a general trend towards demonstrating greater levels of detail in the estimate and more explicit consideration of uncertainties, the latter of which may have an impact on decommissioning project costs. The 2012 report on the International Structure for Decommissioning Costing (ISDC) of Nuclear Installations, a joint recommendation by the Nuclear Energy Agency (NEA), the International Atomic Energy Agency (IAEA) and the European Commission, proposes a standardised structure of cost items for decommissioning projects that can be used either directly for the production of cost estimates or for mapping of cost items for benchmarking purposes. The ISDC, however, provides only limited guidance on the treatment of uncertainty when preparing cost estimates. Addressing Uncertainties in Cost Estimates for Decommissioning Nuclear Facilities, prepared jointly by the NEA and IAEA, is intended to complement the ISDC, assisting cost estimators and reviewers in systematically addressing uncertainties in decommissioning cost estimates. Based on experiences gained in participating countries and projects, the report describes how uncertainty and risks can be analysed and incorporated in decommissioning cost estimates, while presenting the outcomes in a transparent manner

  16. The cost of uncertainty in capacity expansion problems

    Energy Technology Data Exchange (ETDEWEB)

    Jenhung Wang [National Chung Cheng Univ., Dept. of Business Administration, Chia-Yi (Taiwan); Sparrow, F.T. [Purdue Univ., School of Industrial Engineering, West Lafayette, IN (United States)

    1999-07-01

    The goals of this paper are to present a two-stage programming model of the capacity expansion problem under uncertainty of demand and explore the impact of the uncertainty on cost. The model is a mixed integer nonlinear programming (MINLP) model with the consideration of uncertainty used to maximise the expected presented value of utility profits over the planning horizon, under the constraints of rate of return and reserve margin regulation. The results reveal that the uncertainty harms the profit seriously. In this paper both microeconomics and mathematical programming are used to analyse the problem. We try to observe the economic behaviour of the utility with uncertainty involved. We also investigate the influence on the cost of uncertainty of each economic parameter. (Author)

  17. Scientific uncertainty in media content: Introduction to this special issue.

    Science.gov (United States)

    Peters, Hans Peter; Dunwoody, Sharon

    2016-11-01

    This introduction sets the stage for the special issue on the public communication of scientific uncertainty that follows by sketching the wider landscape of issues related to the communication of uncertainty and showing how the individual contributions fit into that landscape. The first part of the introduction discusses the creation of media content as a process involving journalists, scientific sources, stakeholders, and the responsive audience. The second part then provides an overview of the perception of scientific uncertainty presented by the media and the consequences for the recipients' own assessments of uncertainty. Finally, we briefly describe the six research articles included in this special issue. © The Author(s) 2016.

  18. Public Perceptions of Regulatory Costs, Their Uncertainty and Interindividual Distribution.

    Science.gov (United States)

    Johnson, Branden B; Finkel, Adam M

    2016-06-01

    Public perceptions of both risks and regulatory costs shape rational regulatory choices. Despite decades of risk perception studies, this article is the first on regulatory cost perceptions. A survey of 744 U.S. residents probed: (1) How knowledgeable are laypeople about regulatory costs incurred to reduce risks? (2) Do laypeople see official estimates of cost and benefit (lives saved) as accurate? (3) (How) do preferences for hypothetical regulations change when mean-preserving spreads of uncertainty replace certain cost or benefit? and (4) (How) do preferences change when unequal interindividual distributions of hypothetical regulatory costs replace equal distributions? Respondents overestimated costs of regulatory compliance, while assuming agencies underestimate costs. Most assumed agency estimates of benefits are accurate; a third believed both cost and benefit estimates are accurate. Cost and benefit estimates presented without uncertainty were slightly preferred to those surrounded by "narrow uncertainty" (a range of costs or lives entirely within a personally-calibrated zone without clear acceptance or rejection of tradeoffs). Certain estimates were more preferred than "wide uncertainty" (a range of agency estimates extending beyond these personal bounds, thus posing a gamble between favored and unacceptable tradeoffs), particularly for costs as opposed to benefits (but even for costs a quarter of respondents preferred wide uncertainty to certainty). Agency-acknowledged uncertainty in general elicited mixed judgments of honesty and trustworthiness. People preferred egalitarian distributions of regulatory costs, despite skewed actual cost distributions, and preferred progressive cost distributions (the rich pay a greater than proportional share) to regressive ones. Efficient and socially responsive regulations require disclosure of much more information about regulatory costs and risks. © 2016 Society for Risk Analysis.

  19. Performance testing of supercapacitors: Important issues and uncertainties

    Science.gov (United States)

    Zhao, Jingyuan; Gao, Yinghan; Burke, Andrew F.

    2017-09-01

    Supercapacitors are a promising technology for high power energy storage, which have been used in some industrial and vehicles applications. Hence, it is important that information concerning the performance of supercapacitors be detailed and reliable so system designers can make rational decisions regarding the selection of the energy storage components. This paper is concerned with important issues and uncertainties regarding the performance testing of supercapacitors. The effect of different test procedures on the measured characteristics of both commercial and prototype supercapacitors including hybrid supercapacitors have been studied. It was found that the test procedure has a relatively minor effect on the capacitance of carbon/carbon devices and a more significant effect on the capacitance of hybrid supercapacitors. The device characteristic with the greatest uncertainty is the resistance and subsequently the claimed power capability of the device. The energy density should be measured by performing constant power discharges between appropriate voltage limits. This is particularly important in the case of hybrid supercapacitors for which the energy density is rate dependent and the simple relationship E = ½CV2 does not yield accurate estimates of the energy stored. In general, most of the important issues for testing carbon/carbon devices become more serious for hybrid supercapacitors.

  20. Understanding the Uncertainty of an Effectiveness-Cost Ratio in Educational Resource Allocation: A Bayesian Approach

    Science.gov (United States)

    Pan, Yilin

    2016-01-01

    Given the necessity to bridge the gap between what happened and what is likely to happen, this paper aims to explore how to apply Bayesian inference to cost-effectiveness analysis so as to capture the uncertainty of a ratio-type efficiency measure. The first part of the paper summarizes the characteristics of the evaluation data that are commonly…

  1. Uncertainty analysis in raw material and utility cost of biorefinery synthesis and design

    DEFF Research Database (Denmark)

    Cheali, Peam; Quaglia, Alberto; Gernaey, Krist

    2014-01-01

    are characterized by considerable uncertainty. These uncertainties might have significant impact on the results of the design problem, and therefore need to be carefully evaluated and managed, in order to generate candidates for robust design. In this contribution, we study the effect of data uncertainty (raw...... material price and utility cost) on the design of a biorefinery process network....

  2. Addressing imperfect maintenance modelling uncertainty in unavailability and cost based optimization

    International Nuclear Information System (INIS)

    Sanchez, Ana; Carlos, Sofia; Martorell, Sebastian; Villanueva, Jose F.

    2009-01-01

    Optimization of testing and maintenance activities performed in the different systems of a complex industrial plant is of great interest as the plant availability and economy strongly depend on the maintenance activities planned. Traditionally, two types of models, i.e. deterministic and probabilistic, have been considered to simulate the impact of testing and maintenance activities on equipment unavailability and the cost involved. Both models present uncertainties that are often categorized as either aleatory or epistemic uncertainties. The second group applies when there is limited knowledge on the proper model to represent a problem, and/or the values associated to the model parameters, so the results of the calculation performed with them incorporate uncertainty. This paper addresses the problem of testing and maintenance optimization based on unavailability and cost criteria and considering epistemic uncertainty in the imperfect maintenance modelling. It is framed as a multiple criteria decision making problem where unavailability and cost act as uncertain and conflicting decision criteria. A tolerance interval based approach is used to address uncertainty with regard to effectiveness parameter and imperfect maintenance model embedded within a multiple-objective genetic algorithm. A case of application for a stand-by safety related system of a nuclear power plant is presented. The results obtained in this application show the importance of considering uncertainties in the modelling of imperfect maintenance, as the optimal solutions found are associated with a large uncertainty that influences the final decision making depending on, for example, if the decision maker is risk averse or risk neutral

  3. Addressing imperfect maintenance modelling uncertainty in unavailability and cost based optimization

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez, Ana [Department of Statistics and Operational Research, Polytechnic University of Valencia, Camino de Vera, s/n, 46071 Valencia (Spain); Carlos, Sofia [Department of Chemical and Nuclear Engineering, Polytechnic University of Valencia, Camino de Vera, s/n, 46071 Valencia (Spain); Martorell, Sebastian [Department of Chemical and Nuclear Engineering, Polytechnic University of Valencia, Camino de Vera, s/n, 46071 Valencia (Spain)], E-mail: smartore@iqn.upv.es; Villanueva, Jose F. [Department of Chemical and Nuclear Engineering, Polytechnic University of Valencia, Camino de Vera, s/n, 46071 Valencia (Spain)

    2009-01-15

    Optimization of testing and maintenance activities performed in the different systems of a complex industrial plant is of great interest as the plant availability and economy strongly depend on the maintenance activities planned. Traditionally, two types of models, i.e. deterministic and probabilistic, have been considered to simulate the impact of testing and maintenance activities on equipment unavailability and the cost involved. Both models present uncertainties that are often categorized as either aleatory or epistemic uncertainties. The second group applies when there is limited knowledge on the proper model to represent a problem, and/or the values associated to the model parameters, so the results of the calculation performed with them incorporate uncertainty. This paper addresses the problem of testing and maintenance optimization based on unavailability and cost criteria and considering epistemic uncertainty in the imperfect maintenance modelling. It is framed as a multiple criteria decision making problem where unavailability and cost act as uncertain and conflicting decision criteria. A tolerance interval based approach is used to address uncertainty with regard to effectiveness parameter and imperfect maintenance model embedded within a multiple-objective genetic algorithm. A case of application for a stand-by safety related system of a nuclear power plant is presented. The results obtained in this application show the importance of considering uncertainties in the modelling of imperfect maintenance, as the optimal solutions found are associated with a large uncertainty that influences the final decision making depending on, for example, if the decision maker is risk averse or risk neutral.

  4. Uncertainty representation and combination: new results with application to nuclear safety issues

    International Nuclear Information System (INIS)

    Destercke, S.

    2008-10-01

    It often happens that the value of some parameters or variables of a system are imperfectly known, either because of the variability of the modelled phenomena, or because the available information is imprecise or incomplete. Classical probability theory is usually used to treat these uncertainties. However, recent years have witnessed the appearance of arguments pointing to the conclusion that classical probabilities are inadequate to handle imprecise or incomplete information. Other frameworks have thus been proposed to address this problem: the three main are probability sets, random sets and possibility theory. There are many open questions concerning uncertainty treatment within these frameworks. More precisely, it is necessary to build bridges between these three frameworks to advance toward a unified handling of uncertainty. Also, there is a need of practical methods to treat information, as using these frameworks can be computationally costly. In this work, we propose some answers to these two needs for a set of commonly encountered problems. In particular, we focus on the problems of: 1) Uncertainty representation 2) Fusion and evaluation of multiple source information 3) Independence modelling, the aim being to give tools (both of theoretical and practical nature) to treat uncertainty. Some tools are then applied to some problems related to nuclear safety issues. (author)

  5. Costs of travel time uncertainty and benefits of travel time information: Conceptual model and numerical examples

    NARCIS (Netherlands)

    Ettema, D.F.; Timmermans, H.J.P.

    2006-01-01

    A negative effect of congestion that tends to be overlooked is travel time uncertainty. Travel time uncertainty causes scheduling costs due to early or late arrival. The negative effects of travel time uncertainty can be reduced by providing travellers with travel time information, which improves

  6. Low cost high performance uncertainty quantification

    KAUST Repository

    Bekas, C.; Curioni, A.; Fedulova, I.

    2009-01-01

    Uncertainty quantification in risk analysis has become a key application. In this context, computing the diagonal of inverse covariance matrices is of paramount importance. Standard techniques, that employ matrix factorizations, incur a cubic cost

  7. Relationships for Cost and Uncertainty of Decision Trees

    KAUST Repository

    Chikalov, Igor; Hussain, Shahid; Moshkov, Mikhail

    2013-01-01

    This chapter is devoted to the design of new tools for the study of decision trees. These tools are based on dynamic programming approach and need the consideration of subtables of the initial decision table. So this approach is applicable only to relatively small decision tables. The considered tools allow us to compute: 1. Theminimum cost of an approximate decision tree for a given uncertainty value and a cost function. 2. The minimum number of nodes in an exact decision tree whose depth is at most a given value. For the first tool we considered various cost functions such as: depth and average depth of a decision tree and number of nodes (and number of terminal and nonterminal nodes) of a decision tree. The uncertainty of a decision table is equal to the number of unordered pairs of rows with different decisions. The uncertainty of approximate decision tree is equal to the maximum uncertainty of a subtable corresponding to a terminal node of the tree. In addition to the algorithms for such tools we also present experimental results applied to various datasets acquired from UCI ML Repository [4]. © Springer-Verlag Berlin Heidelberg 2013.

  8. Achieving 95% probability level using best estimate codes and the code scaling, applicability and uncertainty (CSAU) [Code Scaling, Applicability and Uncertainty] methodology

    International Nuclear Information System (INIS)

    Wilson, G.E.; Boyack, B.E.; Duffey, R.B.; Griffith, P.; Katsma, K.R.; Lellouche, G.S.; Rohatgi, U.S.; Wulff, W.; Zuber, N.

    1988-01-01

    Issue of a revised rule for loss of coolant accident/emergency core cooling system (LOCA/ECCS) analysis of light water reactors will allow the use of best estimate (BE) computer codes in safety analysis, with uncertainty analysis. This paper describes a systematic methodology, CSAU (Code Scaling, Applicability and Uncertainty), which will provide uncertainty bounds in a cost effective, auditable, rational and practical manner. 8 figs., 2 tabs

  9. Fuel cycle cost uncertainty from nuclear fuel cycle comparison

    International Nuclear Information System (INIS)

    Li, J.; McNelis, D.; Yim, M.S.

    2013-01-01

    This paper examined the uncertainty in fuel cycle cost (FCC) calculation by considering both model and parameter uncertainty. Four different fuel cycle options were compared in the analysis including the once-through cycle (OT), the DUPIC cycle, the MOX cycle and a closed fuel cycle with fast reactors (FR). The model uncertainty was addressed by using three different FCC modeling approaches with and without the time value of money consideration. The relative ratios of FCC in comparison to OT did not change much by using different modeling approaches. This observation was consistent with the results of the sensitivity study for the discount rate. Two different sets of data with uncertainty range of unit costs were used to address the parameter uncertainty of the FCC calculation. The sensitivity study showed that the dominating contributor to the total variance of FCC is the uranium price. In general, the FCC of OT was found to be the lowest followed by FR, MOX, and DUPIC. But depending on the uranium price, the FR cycle was found to have lower FCC over OT. The reprocessing cost was also found to have a major impact on FCC

  10. Quantifying the uncertainty of wave energy conversion device cost for policy appraisal: An Irish case study

    International Nuclear Information System (INIS)

    Farrell, Niall; Donoghue, Cathal O’; Morrissey, Karyn

    2015-01-01

    Wave Energy Conversion (WEC) devices are at a pre-commercial stage of development with feasibility studies sensitive to uncertainties surrounding assumed input costs. This may affect decision making. This paper analyses the impact these uncertainties may have on investor, developer and policymaker decisions using an Irish case study. Calibrated to data present in the literature, a probabilistic methodology is shown to be an effective means to carry this out. Value at Risk (VaR) and Conditional Value at Risk (CVaR) metrics are used to quantify the certainty of achieving a given cost or return on investment. We analyse the certainty of financial return provided by the proposed Irish Feed-in Tariff (FiT) policy. The influence of cost reduction through bulk discount is also discussed, with cost reduction targets for developers identified. Uncertainty is found to have a greater impact on the profitability of smaller installations and those subject to lower rates of cost reduction. This paper emphasises that a premium is required to account for cost uncertainty when setting FiT rates. By quantifying uncertainty, a means to specify an efficient premium is presented. - Highlights: • Probabilistic model quantifies uncertainty for wave energy feasibility analyses. • Methodology presented and applied to an Irish case study. • A feed-in tariff premium of 3–4 c/kWh required to account for cost uncertainty. • Sensitivity of uncertainty and cost to rates of technological change analysed. • Use of probabilistic model for investors and developers also demonstrated

  11. Cost Recommendation under Uncertainty in IQWiG's Efficiency Frontier Framework.

    Science.gov (United States)

    Corro Ramos, Isaac; Lhachimi, Stefan K; Gerber-Grote, Andreas; Al, Maiwenn J

    2017-02-01

    The National Institute for Quality and Efficiency in Health Care (IQWiG) employs an efficiency frontier (EF) framework to facilitate setting maximum reimbursable prices for new interventions. Probabilistic sensitivity analysis (PSA) is used when yes/no reimbursement decisions are sought based on a fixed threshold. In the IQWiG framework, an additional layer of complexity arises as the EF itself may vary its shape in each PSA iteration, and thus the willingness-to-pay, indicated by the EF segments, may vary. To explore the practical problems arising when, within the EF approach, maximum reimbursable prices for new interventions are sought through PSA. When the EF is varied in a PSA, cost recommendations for new interventions may be determined by the mean or the median of the distances between each intervention's point estimate and each EF. Implications of using these metrics were explored in a simulation study based on the model used by IQWiG to assess the cost-effectiveness of 4 antidepressants. Depending on the metric used, cost recommendations can be contradictory. Recommendations based on the mean can also be inconsistent. Results (median) suggested that costs of duloxetine, venlafaxine, mirtazapine, and bupropion should be decreased by €131, €29, €12, and €99, respectively. These recommendations were implemented and the analysis repeated. New results suggested keeping the costs as they were. The percentage of acceptable PSA outcomes increased 41% on average, and the uncertainty associated to the net health benefit was significantly reduced. The median of the distances between every intervention outcome and every EF is a good proxy for the cost recommendation that would be given should the EF be fixed. Adjusting costs according to the median increased the probability of acceptance and reduced the uncertainty around the net health benefit distribution, resulting in a reduced uncertainty for decision makers.

  12. Cost Implications of Uncertainty in CO{sub 2} Storage Resource Estimates: A Review

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Steven T., E-mail: sanderson@usgs.gov [National Center, U.S. Geological Survey (United States)

    2017-04-15

    Carbon capture from stationary sources and geologic storage of carbon dioxide (CO{sub 2}) is an important option to include in strategies to mitigate greenhouse gas emissions. However, the potential costs of commercial-scale CO{sub 2} storage are not well constrained, stemming from the inherent uncertainty in storage resource estimates coupled with a lack of detailed estimates of the infrastructure needed to access those resources. Storage resource estimates are highly dependent on storage efficiency values or storage coefficients, which are calculated based on ranges of uncertain geological and physical reservoir parameters. If dynamic factors (such as variability in storage efficiencies, pressure interference, and acceptable injection rates over time), reservoir pressure limitations, boundaries on migration of CO{sub 2}, consideration of closed or semi-closed saline reservoir systems, and other possible constraints on the technically accessible CO{sub 2} storage resource (TASR) are accounted for, it is likely that only a fraction of the TASR could be available without incurring significant additional costs. Although storage resource estimates typically assume that any issues with pressure buildup due to CO{sub 2} injection will be mitigated by reservoir pressure management, estimates of the costs of CO{sub 2} storage generally do not include the costs of active pressure management. Production of saline waters (brines) could be essential to increasing the dynamic storage capacity of most reservoirs, but including the costs of this critical method of reservoir pressure management could increase current estimates of the costs of CO{sub 2} storage by two times, or more. Even without considering the implications for reservoir pressure management, geologic uncertainty can significantly impact CO{sub 2} storage capacities and costs, and contribute to uncertainty in carbon capture and storage (CCS) systems. Given the current state of available information and the

  13. Effects of utility demand-side management programs on uncertainty

    International Nuclear Information System (INIS)

    Hirst, E.

    1994-01-01

    Electric utilities face a variety of uncertainties that complicate their long-term resource planning. These uncertainties include future economic and load growths, fuel prices, environmental and economic regulations, performance of existing power plants, cost and availability of purchased power, and the costs and performance of new demand and supply resources. As utilities increasingly turn to demand-side management (DSM) programs to provide resources, it becomes more important to analyze the interactions between these programs and the uncertainties facing utilities. This paper uses a dynamic planning model to quantify the uncertainty effects of supply-only vs DSM + supply resource portfolios. The analysis considers four sets of uncertainties: economic growth, fuel prices, the costs to build new power plants, and the costs to operate DSM programs. The two types of portfolios are tested against these four sets of uncertainties for the period 1990 to 2010. Sensitivity, scenario, and worst-case analysis methods are used. The sensitivity analyses show that the DSM + supply resource portfolio is less sensitive to unanticipated changes in economic growth, fuel prices, and power-plant construction costs than is the supply-only portfolio. The supply-only resource mix is better only with respect to uncertainties about the costs of DSM programs. The base-case analysis shows that including DSM programs in the utility's resource portfolio reduces the net present value of revenue requirements (NPV-RR) by 490 million dollars. The scenario-analysis results show an additional 30 million dollars (6%) in benefits associated with reduction in these uncertainties. In the worst-case analysis, the DSM + supply portfolio again reduces the cost penalty associated with guessing wrong for both cases, when the utility plans for high needs and learns it has low needs and vice versa. 20 refs

  14. Cost benchmarking of railway projects in Europe – dealing with uncertainties in cost estimates

    DEFF Research Database (Denmark)

    Trabo, Inara

    Past experiences in the construction of high-speed railway projects demontrate either positive or negative financial outcomes of the actual project’s budget. Usually some uncertainty value is included into initial budget calculations. Uncertainty is related to the increase of material prices...... per main cost drivers were compared and analyzed. There were observed nine railway projects, comparable to the Copenhagen-Ringsted project. The results of this comparison provided a certain overview on the cost range in different budget disciplines. The Copenhagen-Ringsted project is positioned right...

  15. Understanding Cost-Effectiveness of Energy Efficiency Programs: Best Practices, Technical Methods, and Emerging Issues for Policy-Makers

    Science.gov (United States)

    Reviews the issues and approaches involved in considering and adopting cost-effectiveness tests for energy efficiency, including discussing each perspective represented by the five standard cost-effectiveness tests and clarifying key terms.

  16. Rethinking the costs related to global warming. A survey of the issues

    International Nuclear Information System (INIS)

    Ekins, P.

    1995-01-01

    One approach to the economic analysis of global warming seeks to balance the costs of damage from or adaptation to it with the costs of mitigating it. The costs of adaptation and damage have been estimated using techniques of environmental evaluation, but are subject to a wide margin of uncertainty. The costs of mitigation, principally by reducing the emissions of CO 2 , have been estimated using different kinds of economic models, some of the results of which have suggested that very little abatement of carbon emissions is justified before the costs of abatement exceed the benefits of it in terms of foregone damage and adaptation costs. The paper analyses the extent to which this conclusion is a function of the modelling assumptions and techniques used, rather than likely practical outcomes, with regard to the models' treatment of unemployed resources, revenue recycling, prior distortions in the economy due to the tax system and possible dynamic effects from the introduction of a carbon-energy tax. It concludes that, with different and arguably more appropriate treatment of the above issues, especially when the secondary benefits of reducing CO 2 emissions are also taken into account, it is not clear that even substantial reductions in the use of fossil fuels will incur net costs, especially if there is the prospect of even moderate costs from global warming. 4 figs., 8 tabs., 95 refs

  17. Biosimilar medicines and cost-effectiveness

    Directory of Open Access Journals (Sweden)

    Steven Simoens

    2011-02-01

    Full Text Available Steven SimoensResearch Centre for Pharmaceutical Care and Pharmaco-economics, Faculty of Pharmaceutical Sciences, Katholieke Universiteit Leuven, Leuven, BelgiumAbstract: Given that biosimilars are agents that are similar but not identical to the reference biopharmaceutical, this study aims to introduce and describe specific issues related to the economic evaluation of biosimilars by focusing on the relative costs, relative effectiveness, and cost-effectiveness of biosimilars. Economic evaluation assesses the cost-effectiveness of a medicine by comparing the costs and outcomes of a medicine with those of a relevant comparator. The assessment of cost-effectiveness of a biosimilar is complicated by the fact that evidence needed to obtain marketing authorization from a registration authority does not always correspond to the data requirements of a reimbursement authority. In particular, this relates to the availability of adequately powered equivalence or noninferiority studies, the need for comparative data about the effectiveness in a real-world setting rather than the efficacy in a structured setting, and the use of health outcome measures instead of surrogate endpoints. As a biosimilar is likely to be less expensive than the comparator (eg, the reference biopharmaceutical, the assessment of the cost-effectiveness of a biosimilar depends on the relative effectiveness. If appropriately designed and powered clinical studies demonstrate equivalent effectiveness between a biosimilar and the comparator, then a cost-minimization analysis identifies the least expensive medicine. If there are differences in the effectiveness of a biosimilar and the comparator, other techniques of economic evaluation need to be employed, such as cost-effectiveness analysis or cost-utility analysis. Given that there may be uncertainty surrounding the long-term safety (ie, risk of immunogenicity and rare adverse events and effectiveness of a biosimilar, the cost-effectiveness

  18. Demand and generation cost uncertainty modelling in power system optimization studies

    Energy Technology Data Exchange (ETDEWEB)

    Gomes, Bruno Andre; Saraiva, Joao Tome [INESC Porto and Departamento de Engenharia Electrotecnica e Computadores, Faculdade de Engenharia da Universidade do Porto, FEUP, Campus da FEUP Rua Roberto Frias 378, 4200 465 Porto (Portugal)

    2009-06-15

    This paper describes the formulations and the solution algorithms developed to include uncertainties in the generation cost function and in the demand on DC OPF studies. The uncertainties are modelled by trapezoidal fuzzy numbers and the solution algorithms are based on multiparametric linear programming techniques. These models are a development of an initial formulation detailed in several publications co-authored by the second author of this paper. Now, we developed a more complete model and a more accurate solution algorithm in the sense that it is now possible to capture the widest possible range of values of the output variables reflecting both demand and generation cost uncertainties. On the other hand, when modelling simultaneously demand and generation cost uncertainties, we are representing in a more realistic way the volatility that is currently inherent to power systems. Finally, the paper includes a case study to illustrate the application of these models based on the IEEE 24 bus test system. (author)

  19. Using performance indicators to reduce cost uncertainty of China's CO2 mitigation goals

    International Nuclear Information System (INIS)

    Xu, Yuan

    2013-01-01

    Goals on absolute emissions and intensity play key roles in CO 2 mitigation. However, like cap-and-trade policies with price uncertainty, they suffer from significant uncertainty in abatement costs. This article examines whether an indicator could be established to complement CO 2 mitigation goals and help reduce cost uncertainty with a particular focus on China. Performance indicators on CO 2 emissions per unit of energy consumption could satisfy three criteria: compared with the mitigation goals, (i) they are more closely associated with active mitigation efforts and (ii) their baselines have more stable projections from historical trajectories. (iii) Their abatement costs are generally higher than other mitigation methods, particularly energy efficiency and conservation. Performance indicators could be used in the following way: if a CO 2 goal on absolute emissions or intensity is attained, the performance indicator should still reach a lower threshold as a cost floor. If the goal cannot be attained, an upper performance threshold should be achieved as a cost ceiling. The narrower cost uncertainty may encourage wider and greater mitigation efforts. - Highlights: ► CO 2 emissions per unit of energy consumption could act as performance indicators. ► Performance indicators are more closely related to active mitigation activities. ► Performance indicators have more stable historical trajectories. ► Abatement costs are higher for performance indicators than for other activities. ► Performance thresholds could reduce the cost uncertainty of CO 2 mitigation goals.

  20. Calculating utility prudency issue costs

    International Nuclear Information System (INIS)

    Nielsen, K.R.

    1985-01-01

    The nuclear industry, particularly utilities and their construction, engineering and vendor agents, is faced with a surging increase in prudency management audits. What started as primarily a nuclear project-oriented requirement has spread to encompass most significant utility capital construction projects. Such audits are often a precedent condition to commencement of rate hearings. The cost engineer, a primary major capital construction project participant, is required to develop or critique ''prudency issue'' costs as part of such audits. Although utility costs in the broadest sense are potentially at issue, this paper concentrates on the typical project/construction management costs. The costs of design, procurement and construction are all subject to the calculation process

  1. MRI: unique costing and pricing issues.

    Science.gov (United States)

    Schwartz, H W; Jarl, D F

    1985-01-01

    Acquisition of magnetic resonance imaging (MRI) involves a plethora of costs not traditionally encountered in radiology procedure cost accounting models. Experiences with MRI gained at the University of Minnesota Hospitals and Clinics during 1984 uncovered a wide variety of unique costing issues which were eventually identified at the time when the MRI hospital charge was being established. Our experience at UMHC can provide those radiology departments now acquiring MRI with an earlier awareness of these special costing issues, hopefully resulting in better and more timely data collection. Current reimbursement and pricing issues are also having a dramatic impact on MRI costs at each institution and must be assessed in terms of third-party payor intentions.

  2. Task Uncertainty Can Account for Mixing and Switch Costs in Task-Switching

    Science.gov (United States)

    Rennie, Jaime L.

    2015-01-01

    Cognitive control is required in situations that involve uncertainty or change, such as when resolving conflict, selecting responses and switching tasks. Recently, it has been suggested that cognitive control can be conceptualised as a mechanism which prioritises goal-relevant information to deal with uncertainty. This hypothesis has been supported using a paradigm that requires conflict resolution. In this study, we examine whether cognitive control during task switching is also consistent with this notion. We used information theory to quantify the level of uncertainty in different trial types during a cued task-switching paradigm. We test the hypothesis that differences in uncertainty between task repeat and task switch trials can account for typical behavioural effects in task-switching. Increasing uncertainty was associated with less efficient performance (i.e., slower and less accurate), particularly on switch trials and trials that afford little opportunity for advance preparation. Interestingly, both mixing and switch costs were associated with a common episodic control process. These results support the notion that cognitive control may be conceptualised as an information processor that serves to resolve uncertainty in the environment. PMID:26107646

  3. Costs and cost-effectiveness of periviable care.

    Science.gov (United States)

    Caughey, Aaron B; Burchfield, David J

    2014-02-01

    With increasing concerns regarding rapidly expanding healthcare costs, cost-effectiveness analysis allows assessment of whether marginal gains from new technology are worth the increased costs. Particular methodologic issues related to cost and cost-effectiveness analysis in the area of neonatal and periviable care include how costs are estimated, such as the use of charges and whether long-term costs are included; the challenges of measuring utilities; and whether to use a maternal, neonatal, or dual perspective in such analyses. A number of studies over the past three decades have examined the costs and the cost-effectiveness of neonatal and periviable care. Broadly, while neonatal care is costly, it is also cost effective as it produces both life-years and quality-adjusted life-years (QALYs). However, as the gestational age of the neonate decreases, the costs increase and the cost-effectiveness threshold is harder to achieve. In the periviable range of gestational age (22-24 weeks of gestation), whether the care is cost effective is questionable and is dependent on the perspective. Understanding the methodology and salient issues of cost-effectiveness analysis is critical for researchers, editors, and clinicians to accurately interpret results of the growing body of cost-effectiveness studies related to the care of periviable pregnancies and neonates. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Summary of cost projection for regulatory uncertainties in the back end of the fuel cycle

    International Nuclear Information System (INIS)

    Raudenbush, M.H.; Geller, L.

    1977-01-01

    Fuel recycle cost deviations resulting from regulatory changes in the back end of the fuel cycle are examined from a number of different data sources, and three potentially large cost uncertainties are identified; HLW disposal, alpha-waste criteria, and in-plant material control/accountability for safeguards. Present and past methods of regulatory cost effectiveness determinations are critiqued and in some cases found wanting

  5. Epistemic uncertainties and natural hazard risk assessment - Part 1: A review of the issues

    Science.gov (United States)

    Beven, K. J.; Aspinall, W. P.; Bates, P. D.; Borgomeo, E.; Goda, K.; Hall, J. W.; Page, T.; Phillips, J. C.; Rougier, J. T.; Simpson, M.; Stephenson, D. B.; Smith, P. J.; Wagener, T.; Watson, M.

    2015-12-01

    Uncertainties in natural hazard risk assessment are generally dominated by the sources arising from lack of knowledge or understanding of the processes involved. There is a lack of knowledge about frequencies, process representations, parameters, present and future boundary conditions, consequences and impacts, and the meaning of observations in evaluating simulation models. These are the epistemic uncertainties that can be difficult to constrain, especially in terms of event or scenario probabilities, even as elicited probabilities rationalized on the basis of expert judgements. This paper reviews the issues raised by trying to quantify the effects of epistemic uncertainties. Such scientific uncertainties might have significant influence on decisions that are made for risk management, so it is important to communicate the meaning of an uncertainty estimate and to provide an audit trail of the assumptions on which it is based. Some suggestions for good practice in doing so are made.

  6. Introduction to the Special Issue on Climate Ethics: Uncertainty, Values and Policy.

    Science.gov (United States)

    Roeser, Sabine

    2017-10-01

    Climate change is a pressing phenomenon with huge potential ethical, legal and social policy implications. Climate change gives rise to intricate moral and policy issues as it involves contested science, uncertainty and risk. In order to come to scientifically and morally justified, as well as feasible, policies, targeting climate change requires an interdisciplinary approach. This special issue will identify the main challenges that climate change poses from social, economic, methodological and ethical perspectives by focusing on the complex interrelations between uncertainty, values and policy in this context. This special issue brings together scholars from economics, social sciences and philosophy in order to address these challenges.

  7. Task uncertainty can account for mixing and switch costs in task-switching.

    Directory of Open Access Journals (Sweden)

    Patrick S Cooper

    Full Text Available Cognitive control is required in situations that involve uncertainty or change, such as when resolving conflict, selecting responses and switching tasks. Recently, it has been suggested that cognitive control can be conceptualised as a mechanism which prioritises goal-relevant information to deal with uncertainty. This hypothesis has been supported using a paradigm that requires conflict resolution. In this study, we examine whether cognitive control during task switching is also consistent with this notion. We used information theory to quantify the level of uncertainty in different trial types during a cued task-switching paradigm. We test the hypothesis that differences in uncertainty between task repeat and task switch trials can account for typical behavioural effects in task-switching. Increasing uncertainty was associated with less efficient performance (i.e., slower and less accurate, particularly on switch trials and trials that afford little opportunity for advance preparation. Interestingly, both mixing and switch costs were associated with a common episodic control process. These results support the notion that cognitive control may be conceptualised as an information processor that serves to resolve uncertainty in the environment.

  8. Uncertainty and sensitivity analyses of ballast life-cycle cost and payback period

    OpenAIRE

    Mcmahon, James E.

    2000-01-01

    The paper introduces an innovative methology for evaluating the relative significance of energy-efficient technologies applied to fluorescent lamp ballasts. The method involves replacing the point estimates of life cycle cost of the ballasts with uncertainty distributions reflecting the whole spectrum of possible costs, and the assessed probability associated with each value. The results of uncertainty and sensitivity analyses will help analysts reduce effort in data collection and carry on a...

  9. Uncertainty quantification metrics for whole product life cycle cost estimates in aerospace innovation

    Science.gov (United States)

    Schwabe, O.; Shehab, E.; Erkoyuncu, J.

    2015-08-01

    The lack of defensible methods for quantifying cost estimate uncertainty over the whole product life cycle of aerospace innovations such as propulsion systems or airframes poses a significant challenge to the creation of accurate and defensible cost estimates. Based on the axiomatic definition of uncertainty as the actual prediction error of the cost estimate, this paper provides a comprehensive overview of metrics used for the uncertainty quantification of cost estimates based on a literature review, an evaluation of publicly funded projects such as part of the CORDIS or Horizon 2020 programs, and an analysis of established approaches used by organizations such NASA, the U.S. Department of Defence, the ESA, and various commercial companies. The metrics are categorized based on their foundational character (foundations), their use in practice (state-of-practice), their availability for practice (state-of-art) and those suggested for future exploration (state-of-future). Insights gained were that a variety of uncertainty quantification metrics exist whose suitability depends on the volatility of available relevant information, as defined by technical and cost readiness level, and the number of whole product life cycle phases the estimate is intended to be valid for. Information volatility and number of whole product life cycle phases can hereby be considered as defining multi-dimensional probability fields admitting various uncertainty quantification metric families with identifiable thresholds for transitioning between them. The key research gaps identified were the lacking guidance grounded in theory for the selection of uncertainty quantification metrics and lacking practical alternatives to metrics based on the Central Limit Theorem. An innovative uncertainty quantification framework consisting of; a set-theory based typology, a data library, a classification system, and a corresponding input-output model are put forward to address this research gap as the basis

  10. Uncertainty and sensitivity analyses of ballast life-cycle cost and payback period

    Energy Technology Data Exchange (ETDEWEB)

    McMahon, James E.; Liu, Xiaomin; Turiel, Ike; Hakim, Sajid; Fisher, Diane

    2000-06-01

    The paper introduces an innovative methodology for evaluating the relative significance of energy-efficient technologies applied to fluorescent lamp ballasts. The method involves replacing the point estimates of life cycle cost of the ballasts with uncertainty distributions reflecting the whole spectrum of possible costs, and the assessed probability associated with each value. The results of uncertainty and sensitivity analyses will help analysts reduce effort in data collection and carry on analysis more efficiently. These methods also enable policy makers to gain an insightful understanding of which efficient technology alternatives benefit or cost what fraction of consumers, given the explicit assumptions of the analysis.

  11. Hump-shape Uncertainty, Agency Costs and Aggregate Fluctuations

    OpenAIRE

    Lee, Gabriel; Kevin, Salyer; Strobel, Johannes

    2016-01-01

    Previously measured uncertainty shocks using the U.S. data show a hump-shape time path: Uncertainty rises for two years before its decline. Current literature on the effects uncertainty on macroeconomics, including housing, has not accounted for this observation. Consequently, the literature on uncertainty and macroeconomics is divided on the effcts and the propagation mechanism of uncertainty on aggregate uctuations. This paper shows that when uncertainty rises and falls over time, th...

  12. Revised cost savings estimate with uncertainty for enhanced sludge washing of underground storage tank waste

    International Nuclear Information System (INIS)

    DeMuth, S.

    1998-01-01

    Enhanced Sludge Washing (ESW) has been selected to reduce the amount of sludge-based underground storage tank (UST) high-level waste at the Hanford site. During the past several years, studies have been conducted to determine the cost savings derived from the implementation of ESW. The tank waste inventory and ESW performance continues to be revised as characterization and development efforts advance. This study provides a new cost savings estimate based upon the most recent inventory and ESW performance revisions, and includes an estimate of the associated cost uncertainty. Whereas the author's previous cost savings estimates for ESW were compared against no sludge washing, this study assumes the baseline to be simple water washing which more accurately reflects the retrieval activity along. The revised ESW cost savings estimate for all UST waste at Hanford is $6.1 B ± $1.3 B within 95% confidence. This is based upon capital and operating cost savings, but does not include development costs. The development costs are assumed negligible since they should be at least an order of magnitude less than the savings. The overall cost savings uncertainty was derived from process performance uncertainties and baseline remediation cost uncertainties, as determined by the author's engineering judgment

  13. Least-cost Paths - Some Methodological Issues

    Directory of Open Access Journals (Sweden)

    Irmela Herzog

    2014-06-01

    Full Text Available This article deals with methodological issues connected with least-cost path (LCP calculations in archaeology. The number of LCP studies in archaeology has increased rapidly during the last couple of years, but not all of the approaches applied are based on an appropriate model and implementation. Many archaeologists rely on standard GIS software with default settings for calculating LCPs and are not aware of possible alternatives and the pitfalls that are described in this article. After briefly introducing the aims and applications of LCP methods in archaeology, LCP algorithms are discussed. The outcome of the LCP calculations depends not only on the algorithm but also on the cost model, which often includes several cost components. The discussion of the cost components has a focus on slope, because nearly all archaeological LCP studies take this cost component into account and because several methodological issues are connected with slope-based cost models. Other possible cost components are: the load of the walker, vegetation cover, wetlands or other soil properties, travelling and transport on water, water as barrier and as attractor, aspect, altitude, and social or cultural cost components. Eventually, advantages and disadvantages of different ways of combining cost components are presented. Based on the methodological issues I conclude that both validation checks and variations of the model are necessary to analyse the reliability of archaeological LCP results.

  14. Forecasting the Number of Soil Samples Required to Reduce Remediation Cost Uncertainty

    OpenAIRE

    Demougeot-Renard, Hélène; de Fouquet, Chantal; Renard, Philippe

    2008-01-01

    Sampling scheme design is an important step in the management of polluted sites. It largely controls the accuracy of remediation cost estimates. In practice, however, sampling is seldom designed to comply with a given level of remediation cost uncertainty. In this paper, we present a new technique that allows one to estimate of the number of samples that should be taken at a given stage of investigation to reach a forecasted level of accuracy. The uncertainty is expressed both in terms of vol...

  15. Cost-effective management alternatives for Snake River Chinook salmon: a biological-economic synthesis.

    Science.gov (United States)

    Halsing, David L; Moore, Michael R

    2008-04-01

    The mandate to increase endangered salmon populations in the Columbia River Basin of North America has created a complex, controversial resource-management issue. We constructed an integrated assessment model as a tool for analyzing biological-economic trade-offs in recovery of Snake River spring- and summer-run chinook salmon (Oncorhynchus tshawytscha). We merged 3 frameworks: a salmon-passage model to predict migration and survival of smolts; an age-structured matrix model to predict long-term population growth rates of salmon stocks; and a cost-effectiveness analysis to determine a set of least-cost management alternatives for achieving particular population growth rates. We assessed 6 individual salmon-management measures and 76 management alternatives composed of one or more measures. To reflect uncertainty, results were derived for different assumptions of effectiveness of smolt transport around dams. Removal of an estuarine predator, the Caspian Tern (Sterna caspia), was cost-effective and generally increased long-term population growth rates regardless of transport effectiveness. Elimination of adult salmon harvest had a similar effect over a range of its cost estimates. The specific management alternatives in the cost-effective set depended on assumptions about transport effectiveness. On the basis of recent estimates of smolt transport effectiveness, alternatives that discontinued transportation or breached dams were prevalent in the cost-effective set, whereas alternatives that maximized transportation dominated if transport effectiveness was relatively high. More generally, the analysis eliminated 80-90% of management alternatives from the cost-effective set. Application of our results to salmon management is limited by data availability and model assumptions, but these limitations can help guide research that addresses critical uncertainties and information. Our results thus demonstrate that linking biology and economics through integrated models can

  16. A cost-effect analysis of an intervention against radon in homes

    Directory of Open Access Journals (Sweden)

    Hein Stigum

    2009-10-01

    Full Text Available Background  Key words  : Radon exposure, lung cancer, cost-effect analysis, attributable risk, models-mathematical: Radon is a radioactive gas that may leak into buildings from the ground. Radon exposure is a risk factor for lung cancer. An intervention against radon exposure in homes may consist of locating homes with high radon exposure (above 200 Bq m-3 and improving these, and of protecting future houses. The purpose of this paper is to calculate the costs and the effects of this intervention. Methods: We performed a cost-effect analysis from the perspective of the society, followed by an uncertainty and sensitivity analysis. The distribution of radon levels in Norwegian homes is lognormal with mean=74.5 Bq/m3, and 7.6% above 200 Bq/m3. Results: The preventable attributable fraction of radon on lung cancer was 3.8% (95% uncertainty interval: 0.6%, 8.3%. In cumulative present values the intervention would cost $238 (145, 310 million and save 892 (133, 1981 lives, each life saved costs $0.27 (0.09, 0.9 million. The cost-effect ratio was sensitive to the radon risk, the radon exposure distribution, and the latency period of lung cancer. Together these three parameters explained 90% of the variation in the cost-effect ratio. Conclusions: Reducing the radon concentration in present and future homes to below 200 Bq/m3 will cost $0.27 (0.09, 0.9 million per life saved. The uncertainty in the estimated cost per life is large, mainly due to uncertainty in the risk of lung cancer from radon. Based on estimates from road construction, the Norwegian society has been willing to pay $1 million to save a life. We therefore conclude that the intervention against radon in homes is justifiable. The willingness to pay is also larger that the upper uncertainty limit of the cost per life. Our conclusion is therefore robust against the uncertainties in the parameters.

  17. The French biofuels mandates under cost uncertainty - an assessment based on robust optimization

    International Nuclear Information System (INIS)

    Lorne, Daphne; Tchung-Ming, Stephane

    2012-01-01

    This paper investigates the impact of primary energy and technology cost uncertainty on the achievement of renewable and especially biofuel policies - mandates and norms - in France by 2030. A robust optimization technique that allows to deal with uncertainty sets of high dimensionality is implemented in a TIMES-based long-term planning model of the French energy transport and electricity sectors. The energy system costs and potential benefits (GHG emissions abatements, diversification) of the French renewable mandates are assessed within this framework. The results of this systemic analysis highlight how setting norms and mandates allows to reduce the variability of CO 2 emissions reductions and supply mix diversification when the costs of technological progress and prices are uncertain. Beyond that, we discuss the usefulness of robust optimization in complement of other techniques to integrate uncertainty in large-scale energy models. (authors)

  18. Managing the Cost Overrun Risks of Hydroelectric Dams: An Application of Reference Class Forecasting Techniques

    OpenAIRE

    Omotola Awojobi; Glenn P. Jenkins

    2015-01-01

    Hydropower investments have been subject to intense criticism over environmental issues and the common experience with cost uncertainty. In this study we address the issue of uncertainty in cost projections by applying reference class forecasting (RCF) in order to improve the reliability of costs used for making decisions under uncertainty. This technique makes it possible to closely link contingency estimates to the likely incidence of uncertainty of construction costs for hydroelectric dams...

  19. Robust guaranteed cost tracking control of quadrotor UAV with uncertainties.

    Science.gov (United States)

    Xu, Zhiwei; Nian, Xiaohong; Wang, Haibo; Chen, Yinsheng

    2017-07-01

    In this paper, a robust guaranteed cost controller (RGCC) is proposed for quadrotor UAV system with uncertainties to address set-point tracking problem. A sufficient condition of the existence for RGCC is derived by Lyapunov stability theorem. The designed RGCC not only guarantees the whole closed-loop system asymptotically stable but also makes the quadratic performance level built for the closed-loop system have an upper bound irrespective to all admissible parameter uncertainties. Then, an optimal robust guaranteed cost controller is developed to minimize the upper bound of performance level. Simulation results verify the presented control algorithms possess small overshoot and short setting time, with which the quadrotor has ability to perform set-point tracking task well. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  20. External costs of PM2.5 pollution in Beijing, China: Uncertainty analysis of multiple health impacts and costs

    International Nuclear Information System (INIS)

    Yin, Hao; Pizzol, Massimo; Xu, Linyu

    2017-01-01

    Some cities in China are facing serious air pollution problems including high concentrations of particles, SO 2 and NO x . Exposure to PM2.5, one of the primary air pollutants in many cities in China, is highly correlated with various adverse health impacts and ultimately represents a cost for society. The aim of this study is to assess health impacts and external costs related to PM2.5 pollution in Beijing, China with different baseline concentrations and valuation methods. The idea is to provide a reasonable estimate of the total health impacts and external cost due to PM2.5 pollution, as well as a quantification of the relevant uncertainty. PM2.5 concentrations were retrieved for the entire 2012 period in 16 districts of Beijing. The various PM2.5 related health impacts were identified and classified to avoid double counting. Exposure-response coefficients were then obtained from literature. Both the value of statistical life (VSL) and the amended human capital (AHC) approach were applied for external costs estimation, which could provide the upper and lower bound of the external costs due to PM2.5. To fully understand the uncertainty levels, the external cost distribution was determined via Monte Carlo simulation based on the uncertainty of the parameters such as PM2.5 concentration, exposure-response coefficients, and economic cost per case. The results showed that the external costs were equivalent to around 0.3% (AHC, China's guideline: C 0  = 35 μg/m 3 ) to 0.9% (VSL, WHO guideline: C 0  = 10 μg/m 3 ) of regional GDP depending on the valuation method and on the assumed baseline PM2.5 concentration (C 0 ). Among all the health impacts, the economic loss due to premature deaths accounted for more than 80% of the overall external costs. The results of this study could help policymakers prioritizing the PM2.5 pollution control interventions and internalize the external costs through the application of economic policy instruments. - Highlights:

  1. Enhancing regulatory effectiveness by improving the process for identifying and resolving generic issues

    International Nuclear Information System (INIS)

    Vander Molen, Harold J.

    2001-01-01

    The Generic Issues Program first began formally in response to a Commission directive in October of 1976. In 1983, it became one of the first programs to make successful use of probabilistic risk information to aid in regulatory decision-making. In the 16 years since the program became quantitative, 836 issues have been processed. Of these, 106 reactor safety issues were prioritized as requiring further evaluation to determine the final resolution. Approximately a dozen generic issues remain unresolved. Although there is far less reactor licensing activity than in the 1970s, new issues continue to be identified from research and operational experience. These issues often involve complex and controversial questions of safety and regulation, and an efficient and effective means of addressing these issues is essential for regulatory effectiveness. Issues that involve a significant safety question require swift, effective, enforceable, and cost-effective regulatory actions. Issues that are of little safety significance must be quickly shown to be so and dismissed in an expeditious manner so as to avoid unnecessary expenditure of limited resources and to reduce regulatory uncertainty. Additionally, in the time since the generic issue program began, probabilistic risk assessment techniques have advanced significantly while agency resources have continued to diminish. Accordingly, the paper discusses the steps that have been taken to enhance the effectiveness and efficiency of the generic issue resolution process. Additionally, four resolved issues are discussed, along with key elements of a proposed new procedure for resolving potential generic issues

  2. Multi-scenario modelling of uncertainty in stochastic chemical systems

    International Nuclear Information System (INIS)

    Evans, R. David; Ricardez-Sandoval, Luis A.

    2014-01-01

    Uncertainty analysis has not been well studied at the molecular scale, despite extensive knowledge of uncertainty in macroscale systems. The ability to predict the effect of uncertainty allows for robust control of small scale systems such as nanoreactors, surface reactions, and gene toggle switches. However, it is difficult to model uncertainty in such chemical systems as they are stochastic in nature, and require a large computational cost. To address this issue, a new model of uncertainty propagation in stochastic chemical systems, based on the Chemical Master Equation, is proposed in the present study. The uncertain solution is approximated by a composite state comprised of the averaged effect of samples from the uncertain parameter distributions. This model is then used to study the effect of uncertainty on an isomerization system and a two gene regulation network called a repressilator. The results of this model show that uncertainty in stochastic systems is dependent on both the uncertain distribution, and the system under investigation. -- Highlights: •A method to model uncertainty on stochastic systems was developed. •The method is based on the Chemical Master Equation. •Uncertainty in an isomerization reaction and a gene regulation network was modelled. •Effects were significant and dependent on the uncertain input and reaction system. •The model was computationally more efficient than Kinetic Monte Carlo

  3. Sensitivity of LWR fuel cycle costs to uncertainties in detailed thermal cross sections

    International Nuclear Information System (INIS)

    Ryskamp, J.M.; Becker, M.; Harris, D.R.

    1979-01-01

    Cross sections averaged over the thermal energy (< 1 or 2 eV) group have been shown to have an important economic role for light-water reactors. Cost implications of thermal cross section uncertainties at the few-group level were reported earlier. When it has been determined that costs are sensitive to a specific thermal-group cross section, it becomes desirable to determine how specific energy-dependent cross sections influence fuel cycle costs. Multigroup cross-section sensitivity coefficients vary with fuel exposure. By changing the shape of a cross section displayed on a view-tube through an interactive graphics system, one can compute the change in few-group cross section using the exposure dependent sensitivity coefficients. With the changed exposure dependent few-group cross section, a new fuel cycle cost is computed by a sequence of batch depletion, core analysis, and fuel batch cost code modules. Fuel cycle costs are generally most sensitive to cross section uncertainties near the peak of the hardened Maxwellian flux

  4. Issues in assessing the cost-effectiveness of coordinated DSM programs

    International Nuclear Information System (INIS)

    Hill, L.J.; Brown, M.A.

    1995-01-01

    Coordinated demand-side management (DSM) programs, co-administered by government agencies and electric and gas utilities, are likely to grow in importance in the coming years. Because of the unique features of these types of DSM programs, special care must be taken in assessing their cost-effectiveness. In this paper, we discuss these features, suggest how standard cost-effectiveness measures must be adapted to accommodate them, and show how important these adaptations are in assessing the cost-effectiveness of coordinated programs. At first, we use a least-cost, financial approach. The discussion indicates that failure to account properly for the special features of coordinated programs materially affects estimates of cost-effectiveness and, in extreme cases, may lead to rejection of otherwise cost-effective programs. Then extending the analysis to include economic factors, we speculate that most types of coordinated programs are more attractive than when evaluated on a financial basis. (author)

  5. Cultural diversity teaching and issues of uncertainty: the findings of a qualitative study.

    Science.gov (United States)

    Dogra, Nisha; Giordano, James; France, Nicholas

    2007-04-26

    with levels of objectivity and certainty representative of other aspects of the medical curriculum (e.g.--biochemistry). This may reflect a particular selection bias for students with a technocentric orientation. Inadvertently, medical education may enhance this bias through training effects, and accommodate disregard for subjectivity, over-reliance upon technology and thereby foster incorrect assumptions of objective certainty. We opine that it is important to teach students that technology cannot guarantee certainty, and that dealing with subjectivity, diversity, ambiguity and uncertainty is inseparable from the personal dimension of medicine as moral enterprise. Uncertainty is inherent in cultural diversity so this part of the curriculum provides an opportunity to address the issue as it relates to patient care.

  6. Uncertainties in Early Stage Capital Cost Estimation of Process Design – A case study on biorefinery design

    Directory of Open Access Journals (Sweden)

    Gurkan eSin

    2015-02-01

    Full Text Available Capital investment, next to the product demand, sales and production costs, is one of the key metrics commonly used for project evaluation and feasibility assessment. Estimating the investment costs of a new product/process alternative during early stage design is a challenging task. This is especially important in biorefinery research, where available information and experiences with new technologies is limited. A systematic methodology for uncertainty analysis of cost data is proposed that employs (a Bootstrapping as a regression method when cost data is available and (b the Monte Carlo technique as an error propagation method based on expert input when cost data is not available. Four well-known models for early stage cost estimation are reviewed an analyzed using the methodology. The significance of uncertainties of cost data for early stage process design is highlighted using the synthesis and design of a biorefinery as a case study. The impact of uncertainties in cost estimation on the identification of optimal processing paths is found to be profound. To tackle this challenge, a comprehensive techno-economic risk analysis framework is presented to enable robust decision making under uncertainties. One of the results using an order-of-magnitude estimate shows that the production of diethyl ether and 1,3-butadiene are the most promising with economic risks of 0.24 MM$/a and 4.6 MM$/a due to uncertainties in cost estimations, respectively.

  7. Communicating uncertainty in cost-benefit analysis : A cognitive psychological perspective

    NARCIS (Netherlands)

    Mouter, N.; Holleman, M.; Calvert, S.C.; Annema, J.A.

    2013-01-01

    Based on a cognitive psychological theory, this paper aims to improve the communication of uncertainty in Cost-Benefit Analysis. The theory is based on different cognitive-personality and cognitive-social psychological constructs that may help explain individual differences in the processing of

  8. A smart Monte Carlo procedure for production costing and uncertainty analysis

    International Nuclear Information System (INIS)

    Parker, C.; Stremel, J.

    1996-01-01

    Electric utilities using chronological production costing models to decide whether to buy or sell power over the next week or next few weeks need to determine potential profits or losses under a number of uncertainties. A large amount of money can be at stake--often $100,000 a day or more--and one party of the sale must always take on the risk. In the case of fixed price ($/MWh) contracts, the seller accepts the risk. In the case of cost plus contracts, the buyer must accept the risk. So, modeling uncertainty and understanding the risk accurately can improve the competitive edge of the user. This paper investigates an efficient procedure for representing risks and costs from capacity outages. Typically, production costing models use an algorithm based on some form of random number generator to select resources as available or on outage. These algorithms allow experiments to be repeated and gains and losses to be observed in a short time. The authors perform several experiments to examine the capability of three unit outage selection methods and measures their results. Specifically, a brute force Monte Carlo procedure, a Monte Carlo procedure with Latin Hypercube sampling, and a Smart Monte Carlo procedure with cost stratification and directed sampling are examined

  9. Costs and potentials of energy conservation in China's coal-fired power industry: A bottom-up approach considering price uncertainties

    International Nuclear Information System (INIS)

    Chen, Hao; Kang, Jia-Ning; Liao, Hua; Tang, Bao-Jun; Wei, Yi-Ming

    2017-01-01

    Energy conservation technologies in the coal-fired power sector are important solutions for the environmental pollution and climate change issues. However, a unified framework for estimating their costs and potentials is still needed due to the wide technology choices, especially considering their economic feasibility under fuel and carbon price uncertainties. Therefore, this study has employed a bottom-up approach to analyze the costs and potentials of 32 key technologies’ new promotions during the 13th Five-Year Plan period (2016–2020), which combines the conservation supply curve (CSC) approach and break-even analysis. Findings show that (1) these 32 technologies have a total coal conservation potential of 275.77 Mt with a cost of 238.82 billion yuan, and their break-even coal price is 866 yuan/ton. (2) steam-water circulation system has the largest energy conservation potential in the coal-fired power industry. (3) considering the co-benefits will facilitate these technologies’ promotions, because their break-even coal prices will decrease by 2.35 yuan/ton when the carbon prices increase by 1 yuan/ton. (4) discount rates have the largest impacts on the technologies’ cost-effectiveness, while the future generation level affect their energy conservation potentials most. - Highlights: • The 32 technologies can save 275.77 Mt coal with a cost of 238.82 billion yuan. • The steam-water circulation system has the largest energy conservation potential. • Considering the co-benefits will facilitate the technology promotions • Discount rates have the largest impacts on the technologies’ cost-effectiveness.

  10. Cost-Effectiveness of Nicotine Patches for Smoking Cessation in Pregnancy: A Placebo Randomized Controlled Trial (SNAP).

    Science.gov (United States)

    Essex, Holly N; Parrott, Steve; Wu, Qi; Li, Jinshuo; Cooper, Sue; Coleman, Tim

    2015-06-01

    Smoking during pregnancy is the most important, preventable cause of adverse pregnancy outcomes including miscarriage, premature birth, and low birth weight with huge financial costs to the National Health Service. However, there are very few published economic evaluations of smoking cessation interventions in pregnancy and previous studies are predominantly U.S.-based and do not present incremental cost-effectiveness ratios (ICER). A number of studies have demonstrated cost-effectiveness of nicotine replacement therapy (NRT) in the general population, but this has yet to be tested among pregnant smokers. A cost-effectiveness analysis was undertaken alongside the smoking, nicotine, and pregnancy trial to compare NRT patches plus behavioral support to behavioral support alone, for pregnant women who smoked. At delivery, biochemically verified quit rates were slightly higher at 9.4% in the NRT group compared to 7.6% in the control group (odds ratio = 1.26, 95% CI = 0.82-1.96), at an increased cost of around £90 per participant. Higher costs in the NRT group were mainly attributable to the cost of NRT patches (mean = £46.07). The incremental cost-effectiveness ratio associated with NRT was £4,926 per quitter and a sensitivity analysis including only singleton births yielded an ICER of £4,156 per quitter. However, wide confidence intervals indicated a high level of uncertainty. Without a specific willingness to pay threshold, and due to high levels of statistical uncertainty, it is hard to determine the cost-effectiveness of NRT in this population. Furthermore, future research should address compliance issues, as these may dilute any potential effects of NRT, thus reducing the cost-effectiveness. © The Author 2014. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. Planning uncertainties, market risks and new environmental choices: Winning least cost planning combinations

    International Nuclear Information System (INIS)

    Violette, D.; Lang, C.

    1990-01-01

    Utility demand and supply-side planners will face new challenges from environmental regulations. Under current proposals, every ton of pollutant will have a cost to utilities, not just the tons that put them over the allowable limit. Planners will have to account for these new costs. To do this, planners need to start tracking emissions implementation actions today, and begin strategies for future regulatory changes. Current legislative proposals include a tax on the carbon content of fuels to curb emissions of greenhouse gases and substantial reductions in sulfur dioxide and nitrogen oxide emissions. The important issue for planners is the flexible compliance requirements within these regulatory changes. The acid rain proposals, for example, include a market-based emissions trading system for emissions allowances. Whenever there is a competitive market, there are market risks, and potential winners and losers. Utilities need to be prepared to analyze and mitigate these risks. Integrated least cost planing is one way a utility will have to meet this challenge. Planning involves uncertainty and risk. The wide array of compliance choices create countless combinations of strategies for utilities to comply with the new emissions regulations. This paper discusses new compliance strategies, demand-side management (DSM) as a compliance strategy, solutions to DSM traps, and the compliance strategy game

  12. Introduction to the Special Issue on Climate Ethics: Uncertainty, Values and Policy

    OpenAIRE

    Roeser, S.

    2017-01-01

    Climate change is a pressing phenomenon with huge potential ethical, legal and social policy implications. Climate change gives rise to intricate moral and policy issues as it involves contested science, uncertainty and risk. In order to come to scientifically and morally justified, as well as feasible, policies, targeting climate change requires an interdisciplinary approach. This special issue will identify the main challenges that climate change poses from social, economic, methodological ...

  13. Strategic design of cost savings guarantee in energy performance contracting under uncertainty

    International Nuclear Information System (INIS)

    Deng, Qianli; Jiang, Xianglin; Cui, Qingbin; Zhang, Limao

    2015-01-01

    Highlights: • A methodology is proposed to assist Energy Service Companies to maintain competitiveness in winning bids. • Uncertainties within the energy cost savings are modeled stochastically using the Monte-Carlo simulation. • A strategic energy savings guarantee design curve is derived, where all points return as appropriate guarantees. • A campus case is presented to demonstrate the applicability for finding appropriate guaranteed savings value. - Abstract: Among the key barriers to profit in Energy Performance Contracting (EPC) are uncertainties about attaining the realized energy cost savings and potential disputes over the guaranteed cost savings. In this paper, a methodology has been proposed to assist the Energy Service Company (ESCO): (1) to evaluate the risk threshold if the guarantee has already been made, and (2) to determine the guarantee design, if the guarantee has not been made yet, that not only promises the ESCO’s profitability from EPC but also maintains its competitiveness to win the bid. Uncertainties within the energy cost savings are modeled stochastically using Monte-Carlo simulation, taking both the energy price fluctuation and the facility performance variability into account. Based on that, a strategic energy savings guarantee design curve is derived, that all the points on it would return as appropriate guarantees. Finally, a campus case is presented to demonstrate the applicability for finding the appropriate guaranteed savings value. This method is also worth popularizing in similar performance-based projects

  14. The economic implications of carbon cycle uncertainty

    International Nuclear Information System (INIS)

    Smith, Steven J.; Edmonds, James A.

    2006-01-01

    This paper examines the implications of uncertainty in the carbon cycle for the cost of stabilizing carbon dioxide concentrations. Using a state of the art integrated assessment model, we find that uncertainty in our understanding of the carbon cycle has significant implications for the costs of a climate stabilization policy, with cost differences denominated in trillions of dollars. Uncertainty in the carbon cycle is equivalent to a change in concentration target of up to 100 ppmv. The impact of carbon cycle uncertainties are smaller than those for climate sensitivity, and broadly comparable to the effect of uncertainty in technology availability

  15. Estimating the environmental costs of electricity: an overview and review of the issues

    International Nuclear Information System (INIS)

    Freeman, A.M. III

    1996-01-01

    This paper provides an overview of the issues associated with environmental costing and the specific questions raised by the effort to measure the environmental costs of electricity. It focuses on three sets of issues. The first set is several conceptual issues in the valuation of environmental impacts in general. These issues are not unique to valuing the environmental impacts of electricity generation. However each of these issues has been highlighted in one way or another by the studies being discussed here. The second set of issues are specific to the design of studies of environmental effects of generating electricity. These issues are the selection of externalities for inclusion in the analysis, and whether and to what extent to include so called upstream and downstream impacts. The third set of issues involves policy implications of the results of the work that has been done to date. Factors considered include health effects of air emissions, damage to ecosystems, damage by CO 2 . 31 refs

  16. Uncertainty and Variability in Physiologically-Based Pharmacokinetic (PBPK) Models: Key Issues and Case Studies (Final Report)

    Science.gov (United States)

    EPA announced the availability of the final report, Uncertainty and Variability in Physiologically-Based Pharmacokinetic (PBPK) Models: Key Issues and Case Studies. This report summarizes some of the recent progress in characterizing uncertainty and variability in physi...

  17. External costs of PM2.5 pollution in Beijing, China: Uncertainty analysis of multiple health impacts and costs.

    Science.gov (United States)

    Yin, Hao; Pizzol, Massimo; Xu, Linyu

    2017-07-01

    Some cities in China are facing serious air pollution problems including high concentrations of particles, SO 2 and NO x . Exposure to PM2.5, one of the primary air pollutants in many cities in China, is highly correlated with various adverse health impacts and ultimately represents a cost for society. The aim of this study is to assess health impacts and external costs related to PM2.5 pollution in Beijing, China with different baseline concentrations and valuation methods. The idea is to provide a reasonable estimate of the total health impacts and external cost due to PM2.5 pollution, as well as a quantification of the relevant uncertainty. PM2.5 concentrations were retrieved for the entire 2012 period in 16 districts of Beijing. The various PM2.5 related health impacts were identified and classified to avoid double counting. Exposure-response coefficients were then obtained from literature. Both the value of statistical life (VSL) and the amended human capital (AHC) approach were applied for external costs estimation, which could provide the upper and lower bound of the external costs due to PM2.5. To fully understand the uncertainty levels, the external cost distribution was determined via Monte Carlo simulation based on the uncertainty of the parameters such as PM2.5 concentration, exposure-response coefficients, and economic cost per case. The results showed that the external costs were equivalent to around 0.3% (AHC, China's guideline: C 0  = 35 μg/m 3 ) to 0.9% (VSL, WHO guideline: C 0  = 10 μg/m 3 ) of regional GDP depending on the valuation method and on the assumed baseline PM2.5 concentration (C 0 ). Among all the health impacts, the economic loss due to premature deaths accounted for more than 80% of the overall external costs. The results of this study could help policymakers prioritizing the PM2.5 pollution control interventions and internalize the external costs through the application of economic policy instruments. Copyright © 2017

  18. Cost estimating issues in the Russian integrated system planning context

    International Nuclear Information System (INIS)

    Allentuck, J.

    1996-01-01

    An important factor in the credibility of an optimal capacity expansion plan is the accuracy of cost estimates given the uncertainty of future economic conditions. This paper examines the problems associated with estimating investment and operating costs in the Russian nuclear power context over the period 1994 to 2010

  19. Cultural diversity teaching and issues of uncertainty: the findings of a qualitative study

    Directory of Open Access Journals (Sweden)

    Giordano James

    2007-04-01

    -physician relationship. There may be pressure to imbue cultural diversity issues with levels of objectivity and certainty representative of other aspects of the medical curriculum (e.g. – biochemistry. This may reflect a particular selection bias for students with a technocentric orientation. Inadvertently, medical education may enhance this bias through training effects, and accommodate disregard for subjectivity, over-reliance upon technology and thereby foster incorrect assumptions of objective certainty. We opine that it is important to teach students that technology cannot guarantee certainty, and that dealing with subjectivity, diversity, ambiguity and uncertainty is inseparable from the personal dimension of medicine as moral enterprise. Uncertainty is inherent in cultural diversity so this part of the curriculum provides an opportunity to address the issue as it relates to pateint care.

  20. Major issues associated with nuclear power generation cost and their evaluation

    International Nuclear Information System (INIS)

    Matsuo, Yuji; Shimogori, Kei; Suzuki, Atsuhiko

    2015-01-01

    This paper discusses the evaluation of power generation cost that is an important item for energy policy planning. Especially with a focus on nuclear power generation cost, it reviews what will become a focal point on evaluating power generation cost at the present point after the estimates of the 'Investigation Committee on Costs' that was organized by the government have been issued, and what will be a major factor affecting future changes in costs. This paper firstly compared several estimation results on nuclear power generation cost, and extracted/arranged controversial points and unsolved points for discussing nuclear power generation cost. In evaluating nuclear power generation cost, the comparison of capital cost and other costs can give the understanding of what can be important issues. Then, as the main issues, this paper evaluated/discussed the construction cost, operation/maintenance cost, external cost, issue of discount rate, as well as power generation costs in foreign countries and the impact of fossil fuel prices. As other issues related to power generation cost evaluation, it took up expenses for decommissioning, disposal of high-level radioactive waste, and re-processing, outlined the evaluation results by the 'Investigation Committee on Costs,' and compared them with the evaluation examples in foreign countries. These costs do not account for a large share of the entire nuclear power generation costs. The most important point for considering future energy policy is the issue of discount rate, that is, the issue of fund-raising environment for entrepreneurs. This is the factor to greatly affect the economy of future nuclear power generation. (A.O.)

  1. Estimating the uncertainty of damage costs of pollution: A simple transparent method and typical results

    International Nuclear Information System (INIS)

    Spadaro, Joseph V.; Rabl, Ari

    2008-01-01

    Whereas the uncertainty of environmental impacts and damage costs is usually estimated by means of a Monte Carlo calculation, this paper shows that most (and in many cases all) of the uncertainty calculation involves products and/or sums of products and can be accomplished with an analytic solution which is simple and transparent. We present our own assessment of the component uncertainties and calculate the total uncertainty for the impacts and damage costs of the classical air pollutants; results for a Monte Carlo calculation for the dispersion part are also shown. The distribution of the damage costs is approximately lognormal and can be characterized in terms of geometric mean μ g and geometric standard deviation σ g , implying that the confidence interval is multiplicative. We find that for the classical air pollutants σ g is approximately 3 and the 68% confidence interval is [μ g / σ g , μ g σ g ]. Because the lognormal distribution is highly skewed for large σ g , the median is significantly smaller than the mean. We also consider the case where several lognormally distributed damage costs are added, for example to obtain the total damage cost due to all the air pollutants emitted by a power plant, and we find that the relative error of the sum can be significantly smaller than the relative errors of the summands. Even though the distribution for such sums is not exactly lognormal, we present a simple lognormal approximation that is quite adequate for most applications

  2. Planning Water Resources in an Agroforest Ecosystem for Improvement of Regional Ecological Function Under Uncertainties

    Directory of Open Access Journals (Sweden)

    Xueting Zeng

    2018-04-01

    Full Text Available In this study, an agroforestry ecosystem project (AEP is developed for confronting the conflict between agricultural development and forest protection. A fuzzy stochastic programming with Laplace scenario analysis (FSL is proposed for planning water resources in an AEP issue under uncertainties. FSL can not only deal with spatial and temporal variations of hydrologic elements and meteorological conditions; but also handle uncertainties that are expressed in terms of probability, possibility distributions and fuzzy sets; meanwhile, policy scenario analysis with Laplace’s criterion (PSL is introduced to handle probability of each scenario occurrence under the supposition of no data available. The developed FSL can be applied to an AEP issue in Xixian county, located in north of China. The result of ecological effects, water allocation patterns, pollution mitigation schemes and system benefits under various scenarios are obtained, which can support policymakers adjusting current strategy to improve regional ecological function with cost-effective and sustainable manners. Meanwhile, it can support generating a robust water plan for regional sustainability in an AEP issue under uncertainties.

  3. Introduction to the Special Issue on Climate Ethics : Uncertainty, Values and Policy

    NARCIS (Netherlands)

    Roeser, S.

    2017-01-01

    Climate change is a pressing phenomenon with huge potential ethical, legal and social policy implications. Climate change gives rise to intricate moral and policy issues as it involves contested science, uncertainty and risk. In order to come to scientifically and morally justified, as well as

  4. The effect of uncertainty and cooperative behavior on operational performance: Evidence from Brazilian firms

    Directory of Open Access Journals (Sweden)

    Eliane Pereira Zamith Brito

    2017-12-01

    Full Text Available This study aims to examine the effect of managers’ uncertainty on cooperative behavior in interorganizational relationships, and how this affects operational performance. We conducted a survey with 225 Brazilian managers, and analyzed data using confirmatory factor analysis and structural equation modelling. Results present: a a negative influence of uncertainty of state on operational performance; b a positive influence of uncertainty of effect on uncertainty of response; c a significant influence of uncertainty of response on cooperative behavior; and d a positive influence of cooperative behavior on performance. The results indicated that cooperation and uncertainty accounted for 18.8% of the variability of operational performance. Considering the uncertainty that plagues Latin societies, this study can help to create more efficient ways to deal with the phenomenon. Rather than turning a blind eye to uncertainty, our study underscores it and treats it like another business environment issue.

  5. Making choices in health: WHO guide to cost effectiveness analysis

    National Research Council Canada - National Science Library

    Tan Torres Edejer, Tessa

    2003-01-01

    ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67 6. Uncertainty in cost-effectiveness analysis . . . . . . . . . . . . . . . . . . 73 7. 8. Policy uses of Generalized CEA...

  6. Uncertainties in Early-Stage Capital Cost Estimation of Process Design – A Case Study on Biorefinery Design

    International Nuclear Information System (INIS)

    Cheali, Peam; Gernaey, Krist V.; Sin, Gürkan

    2015-01-01

    Capital investment, next to the product demand, sales, and production costs, is one of the key metrics commonly used for project evaluation and feasibility assessment. Estimating the investment costs of a new product/process alternative during early-stage design is a challenging task, which is especially relevant in biorefinery research where information about new technologies and experience with new technologies is limited. A systematic methodology for uncertainty analysis of cost data is proposed that employs: (a) bootstrapping as a regression method when cost data are available; and, (b) the Monte Carlo technique as an error propagation method based on expert input when cost data are not available. Four well-known models for early-stage cost estimation are reviewed and analyzed using the methodology. The significance of uncertainties of cost data for early-stage process design is highlighted using the synthesis and design of a biorefinery as a case study. The impact of uncertainties in cost estimation on the identification of optimal processing paths is indeed found to be profound. To tackle this challenge, a comprehensive techno-economic risk analysis framework is presented to enable robust decision-making under uncertainties. One of the results using order-of-magnitude estimates shows that the production of diethyl ether and 1,3-butadiene are the most promising with the lowest economic risks (among the alternatives considered) of 0.24 MM$/a and 4.6 MM$/a, respectively.

  7. Uncertainties in Early-Stage Capital Cost Estimation of Process Design – A Case Study on Biorefinery Design

    Energy Technology Data Exchange (ETDEWEB)

    Cheali, Peam; Gernaey, Krist V.; Sin, Gürkan, E-mail: gsi@kt.dtu.dk [Department of Chemical and Biochemical Engineering, Technical University of Denmark, Lyngby (Denmark)

    2015-02-06

    Capital investment, next to the product demand, sales, and production costs, is one of the key metrics commonly used for project evaluation and feasibility assessment. Estimating the investment costs of a new product/process alternative during early-stage design is a challenging task, which is especially relevant in biorefinery research where information about new technologies and experience with new technologies is limited. A systematic methodology for uncertainty analysis of cost data is proposed that employs: (a) bootstrapping as a regression method when cost data are available; and, (b) the Monte Carlo technique as an error propagation method based on expert input when cost data are not available. Four well-known models for early-stage cost estimation are reviewed and analyzed using the methodology. The significance of uncertainties of cost data for early-stage process design is highlighted using the synthesis and design of a biorefinery as a case study. The impact of uncertainties in cost estimation on the identification of optimal processing paths is indeed found to be profound. To tackle this challenge, a comprehensive techno-economic risk analysis framework is presented to enable robust decision-making under uncertainties. One of the results using order-of-magnitude estimates shows that the production of diethyl ether and 1,3-butadiene are the most promising with the lowest economic risks (among the alternatives considered) of 0.24 MM$/a and 4.6 MM$/a, respectively.

  8. How uncertainty analysis of streamflow data can reduce costs and promote robust decisions in water management applications

    Science.gov (United States)

    McMillan, Hilary; Seibert, Jan; Petersen-Overleir, Asgeir; Lang, Michel; White, Paul; Snelder, Ton; Rutherford, Kit; Krueger, Tobias; Mason, Robert; Kiang, Julie

    2017-07-01

    Streamflow data are used for important environmental and economic decisions, such as specifying and regulating minimum flows, managing water supplies, and planning for flood hazards. Despite significant uncertainty in most flow data, the flow series for these applications are often communicated and used without uncertainty information. In this commentary, we argue that proper analysis of uncertainty in river flow data can reduce costs and promote robust conclusions in water management applications. We substantiate our argument by providing case studies from Norway and New Zealand where streamflow uncertainty analysis has uncovered economic costs in the hydropower industry, improved public acceptance of a controversial water management policy, and tested the accuracy of water quality trends. We discuss the need for practical uncertainty assessment tools that generate multiple flow series realizations rather than simple error bounds. Although examples of such tools are in development, considerable barriers for uncertainty analysis and communication still exist for practitioners, and future research must aim to provide easier access and usability of uncertainty estimates. We conclude that flow uncertainty analysis is critical for good water management decisions.

  9. Facts and feelings: Framing effects in responses to uncertainties about high-voltage power lines

    OpenAIRE

    de Vries, G.; de Bruijn, J.A.

    2017-01-01

    To ensure power supply security, electricity transmission system operators (TSOs) have to upscale high-voltage overhead power lines. However, upscaling frequently meets opposition. Opposition can be caused by uncertainties about risks and benefits and might lead to costly delays (Linder, 1995; Wiedemann, Boerner,& Claus, 2016). To minimize opposition, TSOs and related public services need to respond to these uncertainties in a credible and convincing (effective) way. Effective risk commun...

  10. Low cost high performance uncertainty quantification

    KAUST Repository

    Bekas, C.

    2009-01-01

    Uncertainty quantification in risk analysis has become a key application. In this context, computing the diagonal of inverse covariance matrices is of paramount importance. Standard techniques, that employ matrix factorizations, incur a cubic cost which quickly becomes intractable with the current explosion of data sizes. In this work we reduce this complexity to quadratic with the synergy of two algorithms that gracefully complement each other and lead to a radically different approach. First, we turned to stochastic estimation of the diagonal. This allowed us to cast the problem as a linear system with a relatively small number of multiple right hand sides. Second, for this linear system we developed a novel, mixed precision, iterative refinement scheme, which uses iterative solvers instead of matrix factorizations. We demonstrate that the new framework not only achieves the much needed quadratic cost but in addition offers excellent opportunities for scaling at massively parallel environments. We based our implementation on BLAS 3 kernels that ensure very high processor performance. We achieved a peak performance of 730 TFlops on 72 BG/P racks, with a sustained performance 73% of theoretical peak. We stress that the techniques presented in this work are quite general and applicable to several other important applications. Copyright © 2009 ACM.

  11. The fuzzy set theory application to the analysis of accident progression event trees with phenomenological uncertainty issues

    International Nuclear Information System (INIS)

    Chun, Moon-Hyun; Ahn, Kwang-Il

    1991-01-01

    Fuzzy set theory provides a formal framework for dealing with the imprecision and vagueness inherent in the expert judgement, and therefore it can be used for more effective analysis of accident progression of PRA where experts opinion is a major means for quantifying some event probabilities and uncertainties. In this paper, an example application of the fuzzy set theory is first made to a simple portion of a given accident progression event tree with typical qualitative fuzzy input data, and thereby computational algorithms suitable for application of the fuzzy set theory to the accident progression event tree analysis are identified and illustrated with example applications. Then the procedure used in the simple example is extended to extremely complex accident progression event trees with a number of phenomenological uncertainty issues, i.e., a typical plant damage state 'SEC' of the Zion Nuclear Power Plant risk assessment. The results show that the fuzzy averages of the fuzzy outcomes are very close to the mean values obtained by current methods. The main purpose of this paper is to provide a formal procedure for application of the fuzzy set theory to accident progression event trees with imprecise and qualitative branch probabilities and/or with a number of phenomenological uncertainty issues. (author)

  12. Technical and governance considerations for advanced metering infrastructure/smart meters: Technology, security, uncertainty, costs, benefits, and risks

    International Nuclear Information System (INIS)

    McHenry, Mark P.

    2013-01-01

    The fundamental role of policymakers when considering Advanced Metering Infrastructure (AMI), or ‘smart meters for energy and water infrastructure is to investigate a broad range of complex interrelated issues. These include alternative technical and non-technical options and deployment needs, the cost and benefits of the infrastructure (risks and mitigation measures), and the impact of a number of stakeholders: consumers, distributors, retailers, competitive market operators, competing technology companies, etc. The scale and number of potential variables in the AMI space is an almost unprecedented challenge to policymakers, with the anticipation of new ancillary products and services, associated market contestability, related regulatory and policy amendments, and the adequacy of consumer protection, education, and safety considerations requiring utmost due-diligence. Embarking on AMI investment entails significant technical, implementation, and strategic risk for governments and administering bodies, and an active effort is required to ensure AMI governance and planning maximises the potential benefits, and minimise uncertainties, costs, and risks to stakeholders. This work seeks to clarify AMI fundamentals and discusses the technical and related governance considerations from a dispassionate perspective, yet acknowledges many stakeholders tend to dichotomise debate, and obfuscate both advantages and benefits, and the converse. - Highlights: • AMI presents an almost unprecedented technical and governance policy challenge. • AMI enables vertical integration of electricity, gas, water, IT, and telco entities • AMI investments involve major technical, implementation, and strategic decisions. • Adequacy of consumer education, safety, privacy, and protection is paramount. • Policy must maximise AMI benefits and minimise uncertainties, costs, and risks

  13. The cost and impact of scaling up pre-exposure prophylaxis for HIV prevention: a systematic review of cost-effectiveness modelling studies

    NARCIS (Netherlands)

    Gomez, Gabriela B.; Borquez, Annick; Case, Kelsey K.; Wheelock, Ana; Vassall, Anna; Hankins, Catherine

    2013-01-01

    Cost-effectiveness studies inform resource allocation, strategy, and policy development. However, due to their complexity, dependence on assumptions made, and inherent uncertainty, synthesising, and generalising the results can be difficult. We assess cost-effectiveness models evaluating expected

  14. A Cost-Effectiveness Analysis of the Swedish Universal Parenting Program All Children in Focus

    Science.gov (United States)

    Ulfsdotter, Malin

    2015-01-01

    Objective There are few health economic evaluations of parenting programs with quality-adjusted life-years (QALYs) as the outcome measure. The objective of this study was, therefore, to conduct a cost-effectiveness analysis of the universal parenting program All Children in Focus (ABC). The goals were to estimate the costs of program implementation, investigate the health effects of the program, and examine its cost-effectiveness. Methods A cost-effectiveness analysis was conducted. Costs included setup costs and operating costs. A parent proxy Visual Analog Scale was used to measure QALYs in children, whereas the General Health Questionnaire-12 was used for parents. A societal perspective was adopted, and the incremental cost-effectiveness ratio was calculated. To account for uncertainty in the estimate, the probability of cost-effectiveness was investigated, and sensitivity analyses were used to account for the uncertainty in cost data. Results The cost was €326.3 per parent, of which €53.7 represented setup costs under the assumption that group leaders on average run 10 groups, and €272.6 was the operating costs. For health effects, the QALY gain was 0.0042 per child and 0.0027 per parent. These gains resulted in an incremental cost-effectiveness ratio for the base case of €47 290 per gained QALY. The sensitivity analyses resulted in ratios from €41 739 to €55 072. With the common Swedish threshold value of €55 000 per QALY, the probability of the ABC program being cost-effective was 50.8 percent. Conclusion Our analysis of the ABC program demonstrates cost-effectiveness ratios below or just above the QALY threshold in Sweden. However, due to great uncertainty about the data, the health economic rationale for implementation should be further studied considering a longer time perspective, effects on siblings, and validated measuring techniques, before full scale implementation. PMID:26681349

  15. A Cost-Effectiveness Analysis of the Swedish Universal Parenting Program All Children in Focus.

    Directory of Open Access Journals (Sweden)

    Malin Ulfsdotter

    Full Text Available There are few health economic evaluations of parenting programs with quality-adjusted life-years (QALYs as the outcome measure. The objective of this study was, therefore, to conduct a cost-effectiveness analysis of the universal parenting program All Children in Focus (ABC. The goals were to estimate the costs of program implementation, investigate the health effects of the program, and examine its cost-effectiveness.A cost-effectiveness analysis was conducted. Costs included setup costs and operating costs. A parent proxy Visual Analog Scale was used to measure QALYs in children, whereas the General Health Questionnaire-12 was used for parents. A societal perspective was adopted, and the incremental cost-effectiveness ratio was calculated. To account for uncertainty in the estimate, the probability of cost-effectiveness was investigated, and sensitivity analyses were used to account for the uncertainty in cost data.The cost was € 326.3 per parent, of which € 53.7 represented setup costs under the assumption that group leaders on average run 10 groups, and € 272.6 was the operating costs. For health effects, the QALY gain was 0.0042 per child and 0.0027 per parent. These gains resulted in an incremental cost-effectiveness ratio for the base case of € 47 290 per gained QALY. The sensitivity analyses resulted in ratios from € 41 739 to € 55 072. With the common Swedish threshold value of € 55 000 per QALY, the probability of the ABC program being cost-effective was 50.8 percent.Our analysis of the ABC program demonstrates cost-effectiveness ratios below or just above the QALY threshold in Sweden. However, due to great uncertainty about the data, the health economic rationale for implementation should be further studied considering a longer time perspective, effects on siblings, and validated measuring techniques, before full scale implementation.

  16. A Cost-Effectiveness Analysis of the Swedish Universal Parenting Program All Children in Focus.

    Science.gov (United States)

    Ulfsdotter, Malin; Lindberg, Lene; Månsdotter, Anna

    2015-01-01

    There are few health economic evaluations of parenting programs with quality-adjusted life-years (QALYs) as the outcome measure. The objective of this study was, therefore, to conduct a cost-effectiveness analysis of the universal parenting program All Children in Focus (ABC). The goals were to estimate the costs of program implementation, investigate the health effects of the program, and examine its cost-effectiveness. A cost-effectiveness analysis was conducted. Costs included setup costs and operating costs. A parent proxy Visual Analog Scale was used to measure QALYs in children, whereas the General Health Questionnaire-12 was used for parents. A societal perspective was adopted, and the incremental cost-effectiveness ratio was calculated. To account for uncertainty in the estimate, the probability of cost-effectiveness was investigated, and sensitivity analyses were used to account for the uncertainty in cost data. The cost was € 326.3 per parent, of which € 53.7 represented setup costs under the assumption that group leaders on average run 10 groups, and € 272.6 was the operating costs. For health effects, the QALY gain was 0.0042 per child and 0.0027 per parent. These gains resulted in an incremental cost-effectiveness ratio for the base case of € 47 290 per gained QALY. The sensitivity analyses resulted in ratios from € 41 739 to € 55 072. With the common Swedish threshold value of € 55 000 per QALY, the probability of the ABC program being cost-effective was 50.8 percent. Our analysis of the ABC program demonstrates cost-effectiveness ratios below or just above the QALY threshold in Sweden. However, due to great uncertainty about the data, the health economic rationale for implementation should be further studied considering a longer time perspective, effects on siblings, and validated measuring techniques, before full scale implementation.

  17. Nuclear Data Uncertainties in 2004: A Perspective

    International Nuclear Information System (INIS)

    Smith, Donald L.

    2005-01-01

    Interest in nuclear data uncertainties is growing robustly after having languished for several years. Renewed attention to this topic is being motivated by the practical need for assuring that nuclear systems will be safe, reliable, and cost effective, according to the individual requirements of each specific nuclear technology. Furthermore, applications are emerging in certain areas of basic nuclear science, e.g., in astrophysics, where, until recently, attention has focused mainly on understanding basic concepts and physics principles rather than on dealing with detailed quantitative information. The availability of fast computers and the concurrent development of sophisticated software enable nuclear data uncertainty information to be used more effectively than ever before. For example, data uncertainties and associated methodologies play useful roles in advanced data measurement, analysis, and evaluation procedures. Unfortunately, the current inventory of requisite uncertainty information is rather limited when measured against these evolving demands. Consequently, there is a real need to generate more comprehensive and reasonable nuclear data uncertainty information, and to make this available relatively soon in suitable form for use in the computer codes employed for nuclear analyses and the development of advanced nuclear energy systems. This conference contribution discusses several conceptual and technical issues that need to be addressed in meeting this demand during the next few years. The role of data uncertainties in several areas of nuclear science will also be mentioned briefly. Finally, the opportunities that ultimately will be afforded by the availability of more extensive and reasonable uncertainty information, and some technical challenges to master, will also be explored in this paper

  18. Cost-effectiveness of pharmacological and psychosocial interventions for schizophrenia

    Science.gov (United States)

    2011-01-01

    Background Information on cost-effectiveness of interventions to treat schizophrenia can assist health policy decision making, particularly given the lack of health resources in developing countries like Thailand. This study aims to determine the optimal treatment package, including drug and non-drug interventions, for schizophrenia in Thailand. Methods A Markov model was used to evaluate the cost-effectiveness of typical antipsychotics, generic risperidone, olanzapine, clozapine and family interventions. Health outcomes were measured in disability adjusted life years. We evaluated intervention benefit by estimating a change in disease severity, taking into account potential side effects. Intervention costs included outpatient treatment costs, hospitalization costs as well as time and travel costs of patients and families. Uncertainty was evaluated using Monte Carlo simulation. A sensitivity analysis of the expected range cost of generic risperidone was undertaken. Results Generic risperidone is more cost-effective than typicals if it can be produced for less than 10 baht per 2 mg tablet. Risperidone was the cheapest treatment with higher drug costs offset by lower hospital costs in comparison to typicals. The most cost-effective combination of treatments was a combination of risperidone (dominant intervention). Adding family intervention has an incremental cost-effectiveness ratio of 1,900 baht/DALY with a 100% probability of a result less than a threshold for very cost-effective interventions of one times GDP or 110,000 baht per DALY. Treating the most severe one third of patients with clozapine instead of risperidone had an incremental cost-effectiveness ratio of 320,000 baht/DALY with just over 50% probability of a result below three times GDP per capita. Conclusions There are good economic arguments to recommend generic risperidone as first line treatment in combination with family intervention. As the uncertainty interval indicates the addition of clozapine

  19. Cost-effectiveness of pharmacological and psychosocial interventions for schizophrenia

    Directory of Open Access Journals (Sweden)

    Vos Theo

    2011-05-01

    Full Text Available Abstract Background Information on cost-effectiveness of interventions to treat schizophrenia can assist health policy decision making, particularly given the lack of health resources in developing countries like Thailand. This study aims to determine the optimal treatment package, including drug and non-drug interventions, for schizophrenia in Thailand. Methods A Markov model was used to evaluate the cost-effectiveness of typical antipsychotics, generic risperidone, olanzapine, clozapine and family interventions. Health outcomes were measured in disability adjusted life years. We evaluated intervention benefit by estimating a change in disease severity, taking into account potential side effects. Intervention costs included outpatient treatment costs, hospitalization costs as well as time and travel costs of patients and families. Uncertainty was evaluated using Monte Carlo simulation. A sensitivity analysis of the expected range cost of generic risperidone was undertaken. Results Generic risperidone is more cost-effective than typicals if it can be produced for less than 10 baht per 2 mg tablet. Risperidone was the cheapest treatment with higher drug costs offset by lower hospital costs in comparison to typicals. The most cost-effective combination of treatments was a combination of risperidone (dominant intervention. Adding family intervention has an incremental cost-effectiveness ratio of 1,900 baht/DALY with a 100% probability of a result less than a threshold for very cost-effective interventions of one times GDP or 110,000 baht per DALY. Treating the most severe one third of patients with clozapine instead of risperidone had an incremental cost-effectiveness ratio of 320,000 baht/DALY with just over 50% probability of a result below three times GDP per capita. Conclusions There are good economic arguments to recommend generic risperidone as first line treatment in combination with family intervention. As the uncertainty interval indicates

  20. Cost-effectiveness of pharmacological and psychosocial interventions for schizophrenia.

    Science.gov (United States)

    Phanthunane, Pudtan; Vos, Theo; Whiteford, Harvey; Bertram, Melanie

    2011-05-13

    Information on cost-effectiveness of interventions to treat schizophrenia can assist health policy decision making, particularly given the lack of health resources in developing countries like Thailand. This study aims to determine the optimal treatment package, including drug and non-drug interventions, for schizophrenia in Thailand. A Markov model was used to evaluate the cost-effectiveness of typical antipsychotics, generic risperidone, olanzapine, clozapine and family interventions. Health outcomes were measured in disability adjusted life years. We evaluated intervention benefit by estimating a change in disease severity, taking into account potential side effects. Intervention costs included outpatient treatment costs, hospitalization costs as well as time and travel costs of patients and families. Uncertainty was evaluated using Monte Carlo simulation. A sensitivity analysis of the expected range cost of generic risperidone was undertaken. Generic risperidone is more cost-effective than typicals if it can be produced for less than 10 baht per 2 mg tablet. Risperidone was the cheapest treatment with higher drug costs offset by lower hospital costs in comparison to typicals. The most cost-effective combination of treatments was a combination of risperidone (dominant intervention). Adding family intervention has an incremental cost-effectiveness ratio of 1,900 baht/DALY with a 100% probability of a result less than a threshold for very cost-effective interventions of one times GDP or 110,000 baht per DALY. Treating the most severe one third of patients with clozapine instead of risperidone had an incremental cost-effectiveness ratio of 320,000 baht/DALY with just over 50% probability of a result below three times GDP per capita. There are good economic arguments to recommend generic risperidone as first line treatment in combination with family intervention. As the uncertainty interval indicates the addition of clozapine may be dominated and there are serious

  1. Adult head CT scans: the uncertainties of effective dose estimates

    International Nuclear Information System (INIS)

    Gregory, Kent J.; Bibbo, Giovanni; Pattison, John E.

    2008-01-01

    Full Text: CT scanning is a high dose imaging modality. Effective dose estimates from CT scans can provide important information to patients and medical professionals. For example, medical practitioners can use the dose to estimate the risk to the patient, and judge whether this risk is outweighed by the benefits of the CT examination, while radiographers can gauge the effect of different scanning protocols on the patient effective dose, and take this into consideration when establishing routine scan settings. Dose estimates also form an important part of epidemiological studies examining the health effects of medical radiation exposures on the wider population. Medical physicists have been devoting significant effort towards estimating patient radiation doses from diagnostic CT scans for some years. The question arises: How accurate are these effective dose estimates? The need for a greater understanding and improvement of the uncertainties in CT dose estimates is now gaining recognition as an important issue (BEIR VII 2006). This study is an attempt to analyse and quantify the uncertainty components relating to effective dose estimates from adult head CT examinations that are calculated with four commonly used methods. The dose estimation methods analysed are the Nagel method, the ImpaCT method, the Wellhoefer method and the Dose-Length Product (DLP) method. The analysis of the uncertainties was performed in accordance with the International Standards Organisation's Guide to the Expression of Uncertainty in Measurement as discussed in Gregory et al (Australas. Phys. Eng. Sci. Med., 28: 131-139, 2005). The uncertainty components vary, depending on the method used to derive the effective dose estimate. Uncertainty components in this study include the statistical and other errors from Monte Carlo simulations, uncertainties in the CT settings and positions of patients in the CT gantry, calibration errors from pencil ionization chambers, the variations in the organ

  2. CT colonography and cost-effectiveness

    Energy Technology Data Exchange (ETDEWEB)

    Mavranezouli, Ifigeneia [University College London, National Collaborating Centre for Mental Health, Centre for Outcomes Research and Effectiveness, Sub-department of Clinical Health Psychology, London (United Kingdom); East, James E. [St Marks Hospital, Imperial College London, Wolfson Unit for Endoscopy, London (United Kingdom); Taylor, Stuart A. [University College Hospital, Specialist X-Ray, London (United Kingdom); University College Hospital, Department of Imaging, London (United Kingdom)

    2008-11-15

    CT colonography (CTC) is increasingly advocated as an effective initial screening tool for colorectal cancer. Nowadays, policy-makers are increasingly interested in cost-effectiveness issues. A number of studies assessing the cost-effectiveness of CTC have been published to date. The majority of findings indicate that CTC is probably not cost-effective when colonoscopy is available, but this conclusion is sensitive to a number of key parameters. This review discusses the findings of these studies, and considers those factors which most influence final conclusions, notably intervention costs, compliance rates, effectiveness of colonoscopy, and the assumed prevalence and natural history of diminutive advanced polyps. (orig.)

  3. CT colonography and cost-effectiveness

    International Nuclear Information System (INIS)

    Mavranezouli, Ifigeneia; East, James E.; Taylor, Stuart A.

    2008-01-01

    CT colonography (CTC) is increasingly advocated as an effective initial screening tool for colorectal cancer. Nowadays, policy-makers are increasingly interested in cost-effectiveness issues. A number of studies assessing the cost-effectiveness of CTC have been published to date. The majority of findings indicate that CTC is probably not cost-effective when colonoscopy is available, but this conclusion is sensitive to a number of key parameters. This review discusses the findings of these studies, and considers those factors which most influence final conclusions, notably intervention costs, compliance rates, effectiveness of colonoscopy, and the assumed prevalence and natural history of diminutive advanced polyps. (orig.)

  4. Revisiting organizational interpretation and three types of uncertainty

    DEFF Research Database (Denmark)

    Sund, Kristian J.

    2015-01-01

    that might help explain and untangle some of the conflicting empirical results found in the extant literature. The paper illustrates how the literature could benefit from re-conceptualizing the perceived environmental uncertainty construct to take into account different types of uncertainty. Practical....... Design/methodology/approach – This conceptual paper extends existing conceptual work by distinguishing between general and issue-specific scanning and linking the interpretation process to three different types of perceived uncertainty: state, effect and response uncertainty. Findings – It is proposed...... on existing work by linking the interpretation process to three different types of uncertainty (state, effect and response uncertainty) with several novel and testable propositions. The paper also differentiates clearly general (regular) scanning from issue-specific (irregular) scanning. Finally, the paper...

  5. Optimization of Korean energy planning for sustainability considering uncertainties in learning rates and external factors

    International Nuclear Information System (INIS)

    Kim, Seunghyok; Koo, Jamin; Lee, Chang Jun; Yoon, En Sup

    2012-01-01

    During the last few decades, energy planning has focused on meeting domestic demand at lower total costs. However, global warming and the shared recognition of it have transformed the problem of energy planning into a more complex task with a greater number of issues to be considered. Since the key issue is to reduce greenhouse effects, governments around the world have begun to make investments in renewable energy systems (e.g., hydro, wind, solar, and/or biomass power). The relatively high costs of renewable energy systems and the uncertain outlook of their rate of diffusion in the market make it difficult to heavily rely on them. The uncertain variations in production cost over time are especially challenging. To handle uncertainties, the concept of the learning rate was adopted in this study so as to compute the costs of energy systems in the future and Monte Carlo simulation was performed. The aim of this study was to optimize plans of conventional and prospective renewable energy systems with respect to production cost. The production cost included capital, fixed, variable, and external costs. For the case study, the energy situation in South Korea was used. The results of the case study where the proposed methodology was applied could provide useful insights economically and strategies of sustainable energy management for ambiguous environments. -- Highlights: ► We propose energy planning method for sustainability. ► We consider uncertainties such as learning rate, fuel prices, and CO 2 prices. ► We consider the possibility of CO 2 trading. ► The proposed method is applied to South Korea case. ► The added capacities of energy systems depend on uncertainties.

  6. Technologies to Support Community-Dwelling Persons With Dementia: A Position Paper on Issues Regarding Development, Usability, Effectiveness and Cost-Effectiveness, Deployment, and Ethics

    Science.gov (United States)

    Innes, Anthea; Mountain, Gail; Robinson, Louise; van der Roest, Henriëtte; García-Casal, J Antonio; Gove, Dianne; Thyrian, Jochen René; Evans, Shirley; Dröes, Rose-Marie; Kelly, Fiona; Kurz, Alexander; Casey, Dympna; Szcześniak, Dorota; Dening, Tom; Craven, Michael P; Span, Marijke; Felzmann, Heike; Tsolaki, Magda; Franco-Martin, Manuel

    2017-01-01

    Background With the expected increase in the numbers of persons with dementia, providing timely, adequate, and affordable care and support is challenging. Assistive and health technologies may be a valuable contribution in dementia care, but new challenges may emerge. Objective The aim of our study was to review the state of the art of technologies for persons with dementia regarding issues on development, usability, effectiveness and cost-effectiveness, deployment, and ethics in 3 fields of application of technologies: (1) support with managing everyday life, (2) support with participating in pleasurable and meaningful activities, and (3) support with dementia health and social care provision. The study also aimed to identify gaps in the evidence and challenges for future research. Methods Reviews of literature and expert opinions were used in our study. Literature searches were conducted on usability, effectiveness and cost-effectiveness, and ethics using PubMed, Embase, CINAHL, and PsycINFO databases with no time limit. Selection criteria in our selected technology fields were reviews in English for community-dwelling persons with dementia. Regarding deployment issues, searches were done in Health Technology Assessment databases. Results According to our results, persons with dementia want to be included in the development of technologies; there is little research on the usability of assistive technologies; various benefits are reported but are mainly based on low-quality studies; barriers to deployment of technologies in dementia care were identified, and ethical issues were raised by researchers but often not studied. Many challenges remain such as including the target group more often in development, performing more high-quality studies on usability and effectiveness and cost-effectiveness, creating and having access to high-quality datasets on existing technologies to enable adequate deployment of technologies in dementia care, and ensuring that ethical

  7. Cost-effectiveness thresholds: pros and cons.

    Science.gov (United States)

    Bertram, Melanie Y; Lauer, Jeremy A; De Joncheere, Kees; Edejer, Tessa; Hutubessy, Raymond; Kieny, Marie-Paule; Hill, Suzanne R

    2016-12-01

    Cost-effectiveness analysis is used to compare the costs and outcomes of alternative policy options. Each resulting cost-effectiveness ratio represents the magnitude of additional health gained per additional unit of resources spent. Cost-effectiveness thresholds allow cost-effectiveness ratios that represent good or very good value for money to be identified. In 2001, the World Health Organization's Commission on Macroeconomics in Health suggested cost-effectiveness thresholds based on multiples of a country's per-capita gross domestic product (GDP). In some contexts, in choosing which health interventions to fund and which not to fund, these thresholds have been used as decision rules. However, experience with the use of such GDP-based thresholds in decision-making processes at country level shows them to lack country specificity and this - in addition to uncertainty in the modelled cost-effectiveness ratios - can lead to the wrong decision on how to spend health-care resources. Cost-effectiveness information should be used alongside other considerations - e.g. budget impact and feasibility considerations - in a transparent decision-making process, rather than in isolation based on a single threshold value. Although cost-effectiveness ratios are undoubtedly informative in assessing value for money, countries should be encouraged to develop a context-specific process for decision-making that is supported by legislation, has stakeholder buy-in, for example the involvement of civil society organizations and patient groups, and is transparent, consistent and fair.

  8. Costs without benefits? Methodological issues in assessing costs, benefits and effectiveness of water protection policies. Paper

    Energy Technology Data Exchange (ETDEWEB)

    Walz, R.; Schleich, J.

    2000-07-01

    In the last few years, the conditions for extending environmental policy in general and policy dealing with the prevention of water pollution in particular have undergone extensive changes. On the one hand, there has been indisputable considerable success in preventing water pollution which has led to less direct pressure for policy action. On the other hand, the rising sewage levies and the lower political priority assigned in general to environmental policy documented in, e. g. public opinion surveys, has led to water pollution control policy facing very different pressures of justification: more efficient use of funds, improved planning processes, proof of the achievable benefit, but also stopping the increase in levies or not hindering economic development, these or similar slogans are the objections brought against water pollution control. Regardless of how unambiguous these terms appear when used as slogans in this way, they become diffuse and unclear if regarded more closely. This paper therefore attempts to reveal the reasons for possible misunderstandings and misinterpretations on the one hand and, on the other, to reveal the basic problems and uncertainties which are necessarily linked with an assessment of costs and benefits. In order to do this, three areas are examined: level of actors and analysis, evaluation methods and assessment of costs and benefits. (orig.)

  9. Mechanics and uncertainty

    CERN Document Server

    Lemaire, Maurice

    2014-01-01

    Science is a quest for certainty, but lack of certainty is the driving force behind all of its endeavors. This book, specifically, examines the uncertainty of technological and industrial science. Uncertainty and Mechanics studies the concepts of mechanical design in an uncertain setting and explains engineering techniques for inventing cost-effective products. Though it references practical applications, this is a book about ideas and potential advances in mechanical science.

  10. SunShot solar power reduces costs and uncertainty in future low-carbon electricity systems.

    Science.gov (United States)

    Mileva, Ana; Nelson, James H; Johnston, Josiah; Kammen, Daniel M

    2013-08-20

    The United States Department of Energy's SunShot Initiative has set cost-reduction targets of $1/watt for central-station solar technologies. We use SWITCH, a high-resolution electricity system planning model, to study the implications of achieving these targets for technology deployment and electricity costs in western North America, focusing on scenarios limiting carbon emissions to 80% below 1990 levels by 2050. We find that achieving the SunShot target for solar photovoltaics would allow this technology to provide more than a third of electric power in the region, displacing natural gas in the medium term and reducing the need for nuclear and carbon capture and sequestration (CCS) technologies, which face technological and cost uncertainties, by 2050. We demonstrate that a diverse portfolio of technological options can help integrate high levels of solar generation successfully and cost-effectively. The deployment of GW-scale storage plays a central role in facilitating solar deployment and the availability of flexible loads could increase the solar penetration level further. In the scenarios investigated, achieving the SunShot target can substantially mitigate the cost of implementing a carbon cap, decreasing power costs by up to 14% and saving up to $20 billion ($2010) annually by 2050 relative to scenarios with Reference solar costs.

  11. Predicted costs of environmental controls for a commercial oil shale industry. Volume II. A subjective self-assessment of uncertainty in the predicted costs

    Energy Technology Data Exchange (ETDEWEB)

    Jovanovich, A.P.; Stone, M.L.; Taylor, G.C.

    1979-07-01

    The uncertainties in Volume I without extensive additional engineering effort were identified and quantified. Substantial uncertainty was found in several critical variables, allowing a broad range of possible values. Calculations of the cost impact associated with such broad ranges, however, did not always result in significant differences. Seven major areas of pollution control activity were judged to warrant the assessment effort. Three of these areas were found to contain significant uncertainty and additional research is suggested. These areas are: H/sub 2/S removal from the retort gas stream (Stretford process); organic removal from process wastewaters (bio-oxidation or other alternatives); and slurry backfilling of spent Modified In Situ (MIS) retorts. The overall results of the assessment and analysis process are summarized in Table 1-1 in terms of total cost for pollution control. The distributions have been divided into three ranges in this table. A center range is given which contains 80% to 90% probability, and the costs outside this range with probabilities are given. The full distributions can be found in Section 5.0. The subjective probability distributions are a quantification of opinion. The probability of encountering costs below the low figure or above the high figure for each process and scenario is judged to be nearly zero.

  12. Modeling and solving a large-scale generation expansion planning problem under uncertainty

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Shan; Ryan, Sarah M. [Iowa State University, Department of Industrial and Manufacturing Systems Engineering, Ames (United States); Watson, Jean-Paul [Sandia National Laboratories, Discrete Math and Complex Systems Department, Albuquerque (United States); Woodruff, David L. [University of California Davis, Graduate School of Management, Davis (United States)

    2011-11-15

    We formulate a generation expansion planning problem to determine the type and quantity of power plants to be constructed over each year of an extended planning horizon, considering uncertainty regarding future demand and fuel prices. Our model is expressed as a two-stage stochastic mixed-integer program, which we use to compute solutions independently minimizing the expected cost and the Conditional Value-at-Risk; i.e., the risk of significantly larger-than-expected operational costs. We introduce stochastic process models to capture demand and fuel price uncertainty, which are in turn used to generate trees that accurately represent the uncertainty space. Using a realistic problem instance based on the Midwest US, we explore two fundamental, unexplored issues that arise when solving any stochastic generation expansion model. First, we introduce and discuss the use of an algorithm for computing confidence intervals on obtained solution costs, to account for the fact that a finite sample of scenarios was used to obtain a particular solution. Second, we analyze the nature of solutions obtained under different parameterizations of this method, to assess whether the recommended solutions themselves are invariant to changes in costs. The issues are critical for decision makers who seek truly robust recommendations for generation expansion planning. (orig.)

  13. Integrating uncertainties for climate change mitigation

    Science.gov (United States)

    Rogelj, Joeri; McCollum, David; Reisinger, Andy; Meinshausen, Malte; Riahi, Keywan

    2013-04-01

    The target of keeping global average temperature increase to below 2°C has emerged in the international climate debate more than a decade ago. In response, the scientific community has tried to estimate the costs of reaching such a target through modelling and scenario analysis. Producing such estimates remains a challenge, particularly because of relatively well-known, but ill-quantified uncertainties, and owing to limited integration of scientific knowledge across disciplines. The integrated assessment community, on one side, has extensively assessed the influence of technological and socio-economic uncertainties on low-carbon scenarios and associated costs. The climate modelling community, on the other side, has worked on achieving an increasingly better understanding of the geophysical response of the Earth system to emissions of greenhouse gases (GHG). This geophysical response remains a key uncertainty for the cost of mitigation scenarios but has only been integrated with assessments of other uncertainties in a rudimentary manner, i.e., for equilibrium conditions. To bridge this gap between the two research communities, we generate distributions of the costs associated with limiting transient global temperature increase to below specific temperature limits, taking into account uncertainties in multiple dimensions: geophysical, technological, social and political. In other words, uncertainties resulting from our incomplete knowledge about how the climate system precisely reacts to GHG emissions (geophysical uncertainties), about how society will develop (social uncertainties and choices), which technologies will be available (technological uncertainty and choices), when we choose to start acting globally on climate change (political choices), and how much money we are or are not willing to spend to achieve climate change mitigation. We find that political choices that delay mitigation have the largest effect on the cost-risk distribution, followed by

  14. Securitization of residential solar photovoltaic assets: Costs, risks and uncertainty

    International Nuclear Information System (INIS)

    Alafita, T.; Pearce, J.M.

    2014-01-01

    Limited access to low-cost financing is an impediment to high-velocity technological diffusion and high grid penetration of solar photovoltaic (PV) technology. Securitization of solar assets provides a potential solution to this problem. This paper assesses the viability of solar asset-backed securities (ABS) as a lower cost financing mechanism and identifies policies that could facilitate implementation of securitization. First, traditional solar financing is examined to provide a baseline for cost comparisons. Next, the securitization process is modeled. The model enables identification of several junctures at which risk and uncertainty influence costs. Next, parameter values are assigned and used to generate cost estimates. Results show that, under reasonable assumptions, securitization of solar power purchase agreements (PPA) can significantly reduce project financing costs, suggesting that securitization is a viable mechanism for improving the financing of PV projects. The clear impediment to the successful launch of a solar ABS is measuring and understanding the riskiness of underlying assets. This study identifies three classes of policy intervention that lower the cost of ABS by reducing risk or by improving the measurement of risk: (i) standardization of contracts and the contracting process, (ii) improved access to contract and equipment performance data, and (iii) geographic diversification. - Highlights: • Limited access to low-cost financing is hampering penetration of solar PV. • Solar asset-backed securities (ABS) provide a low cost financing mechanism. • Results for securitization of solar leases and power purchase agreements (PPA). • Securitization can significantly reduce project financing costs. • Identifies policy intervention that lower cost of ABS by reducing risk

  15. Energy supply planning in Iran by using fuzzy linear programming approach (regarding uncertainties of investment costs)

    International Nuclear Information System (INIS)

    Sadeghi, Mehdi; Mirshojaeian Hosseini, Hossein

    2006-01-01

    For many years, energy models have been used in developed or developing countries to satisfy different needs in energy planning. One of major problems against energy planning and consequently energy models is uncertainty, spread in different economic, political and legal dimensions of energy planning. Confronting uncertainty, energy planners have often used two well-known strategies. The first strategy is stochastic programming, in which energy system planners define different scenarios and apply an explicit probability of occurrence to each scenario. The second strategy is Minimax Regret strategy that minimizes regrets of different decisions made in energy planning. Although these strategies have been used extensively, they could not flexibly and effectively deal with the uncertainties caused by fuzziness. 'Fuzzy Linear Programming (FLP)' is a strategy that can take fuzziness into account. This paper tries to demonstrate the method of application of FLP for optimization of supply energy system in Iran, as a case study. The used FLP model comprises fuzzy coefficients for investment costs. Following the mentioned purpose, it is realized that FLP is an easy and flexible approach that can be a serious competitor for other confronting uncertainties approaches, i.e. stochastic and Minimax Regret strategies. (author)

  16. The cost and impact of scaling up pre-exposure prophylaxis for HIV prevention: a systematic review of cost-effectiveness modelling studies.

    Directory of Open Access Journals (Sweden)

    Gabriela B Gomez

    Full Text Available Cost-effectiveness studies inform resource allocation, strategy, and policy development. However, due to their complexity, dependence on assumptions made, and inherent uncertainty, synthesising, and generalising the results can be difficult. We assess cost-effectiveness models evaluating expected health gains and costs of HIV pre-exposure prophylaxis (PrEP interventions.We conducted a systematic review comparing epidemiological and economic assumptions of cost-effectiveness studies using various modelling approaches. The following databases were searched (until January 2013: PubMed/Medline, ISI Web of Knowledge, Centre for Reviews and Dissemination databases, EconLIT, and region-specific databases. We included modelling studies reporting both cost and expected impact of a PrEP roll-out. We explored five issues: prioritisation strategies, adherence, behaviour change, toxicity, and resistance. Of 961 studies retrieved, 13 were included. Studies modelled populations (heterosexual couples, men who have sex with men, people who inject drugs in generalised and concentrated epidemics from Southern Africa (including South Africa, Ukraine, USA, and Peru. PrEP was found to have the potential to be a cost-effective addition to HIV prevention programmes in specific settings. The extent of the impact of PrEP depended upon assumptions made concerning cost, epidemic context, programme coverage, prioritisation strategies, and individual-level adherence. Delivery of PrEP to key populations at highest risk of HIV exposure appears the most cost-effective strategy. Limitations of this review include the partial geographical coverage, our inability to perform a meta-analysis, and the paucity of information available exploring trade-offs between early treatment and PrEP.Our review identifies the main considerations to address in assessing cost-effectiveness analyses of a PrEP intervention--cost, epidemic context, individual adherence level, PrEP programme coverage

  17. Cost effective tools for soil organic carbon monitoring

    Science.gov (United States)

    Shepherd, Keith; Aynekulu, Ermias

    2013-04-01

    There is increasing demand for data on soil properties at fine spatial resolution to support management and planning decisions. Measurement of soil organic carbon has attracted much interest because (i) soil organic carbon is widely cited as a useful indicator of soil condition and (ii) of the importance of soil carbon in the global carbon cycle and climate mitigation strategies. However in considering soil measurement designs there has been insufficient attention given to careful analysis of the specific decisions that the measurements are meant to support and on what measurements have high information value for decision-making. As a result, much measurement effort may be wasted or focused on the wrong variables. A cost-effective measurement is one that reduces risk in decisions and does not cost more than the societal returns to additional evidence. A key uncertainty in measuring soil carbon as a soil condition indicator is what constitutes a good or bad level of carbon on a given soil. A measure of soil organic carbon concentration may have limited value for informing management decisions without the additional information required to interpret it, and so expending further efforts on improving measurements to increase precision may then have no value to improving the decision. Measuring soil carbon stock changes for carbon trading purposes requires high levels of measurement precision but there is still large uncertainty on whether the costs of measurement exceed the benefits. Since the largest cost component in soil monitoring is often travel to the field and physically sampling soils, it is generally cost-effective to meet multiple objectives by analysing a number of properties on a soil sample. Diffuse reflectance infrared spectroscopy is playing a key role in allowing multiple soil properties to be determined rapidly and at low cost. The method provides estimation of multiple soil properties (e.g. soil carbon, texture and mineralogy) in one measurement

  18. Cost effectiveness of tobacco control policies in Vietnam: the case of population-level interventions.

    Science.gov (United States)

    Higashi, Hideki; Truong, Khoa D; Barendregt, Jan J; Nguyen, Phuong K; Vuong, Mai L; Nguyen, Thuy T; Hoang, Phuong T; Wallace, Angela L; Tran, Tien V; Le, Cuong Q; Doran, Christopher M

    2011-05-01

    Tobacco smoking is one of the leading public health problems in the world. It is also possible to prevent and/or reduce the harm from tobacco use through the use of cost-effective tobacco control measures. However, most of this evidence comes from developed countries and little research has been conducted on this issue in developing countries. The objective of this study was to analyse the cost effectiveness of four population-level tobacco control interventions in Vietnam. Four tobacco control interventions were evaluated: excise tax increase; graphic warning labels on cigarette packs; mass media campaigns; and smoking bans (in public or in work places). A multi-state life table model was constructed in Microsoft® Excel to examine the cost effectiveness of the tobacco control intervention options. A government perspective was adopted, with costing conducted using a bottom-up approach. Health improvement was considered in terms of disability-adjusted life-years (DALYs) averted. All assumptions were subject to sensitivity and uncertainty analysis. All the interventions fell within the definition of being very cost effective according to the threshold level suggested by the WHO (i.e. place smoking bans. If the cost offset was included in the analysis, all interventions would provide cost savings to the government health sector. All four interventions to reduce the harm from tobacco use appear to be highly cost effective and should be considered as priorities in the context of Vietnam. The government may initially consider graphic warning labels and tax increase, followed by other interventions.

  19. Sunk costs equal sunk boats? The effect of entry costs in a transboundary sequential fishery

    DEFF Research Database (Denmark)

    Punt, M. J.

    2017-01-01

    that for other fisheries substantial sunk investments are needed. In this paper I investigate the effect of such sunk entry costs in a sequential fisheries. I model the uncertainty as a shock to the stock dependent fishing costs, in a two player game, where one of the players faces sunk entry costs. I find that......, depending on parameters, sunk costs can i) increase the competitive pressure on the fish stock compared to a game where entry is free ii) act as a deterrence mechanism and iii) act as a commitment device. I conclude that entry costs can play a crucial role because they can change the outcome of the game...

  20. Key issues for low-cost FGD installations

    Energy Technology Data Exchange (ETDEWEB)

    DePriest, W.; Mazurek, J.M. [Sargent & Lundy LLC, Chicago, IL (United States)

    1995-12-01

    This paper will discuss various methods for installing low-cost FGD systems. The paper will include a discussion of various types of FGD systems available, both wet and dry, and will compare the relative cost of each type. Important design issues, such as use of spare equipment, materials of construction, etc. will be presented. An overview of various low-cost construction techniques (i.e., modularization) will be included. This paper will draw heavily from Sargent & Lundy`s database of past and current FGD projects together with information we gathered for several Electric Power Research Institute (EPRI) studies on the subject.

  1. Uncertainty and validation. Effect of model complexity on uncertainty estimates

    Energy Technology Data Exchange (ETDEWEB)

    Elert, M. [Kemakta Konsult AB, Stockholm (Sweden)] [ed.

    1996-09-01

    In the Model Complexity subgroup of BIOMOVS II, models of varying complexity have been applied to the problem of downward transport of radionuclides in soils. A scenario describing a case of surface contamination of a pasture soil was defined. Three different radionuclides with different environmental behavior and radioactive half-lives were considered: Cs-137, Sr-90 and I-129. The intention was to give a detailed specification of the parameters required by different kinds of model, together with reasonable values for the parameter uncertainty. A total of seven modelling teams participated in the study using 13 different models. Four of the modelling groups performed uncertainty calculations using nine different modelling approaches. The models used range in complexity from analytical solutions of a 2-box model using annual average data to numerical models coupling hydrology and transport using data varying on a daily basis. The complex models needed to consider all aspects of radionuclide transport in a soil with a variable hydrology are often impractical to use in safety assessments. Instead simpler models, often box models, are preferred. The comparison of predictions made with the complex models and the simple models for this scenario show that the predictions in many cases are very similar, e g in the predictions of the evolution of the root zone concentration. However, in other cases differences of many orders of magnitude can appear. One example is the prediction of the flux to the groundwater of radionuclides being transported through the soil column. Some issues that have come to focus in this study: There are large differences in the predicted soil hydrology and as a consequence also in the radionuclide transport, which suggests that there are large uncertainties in the calculation of effective precipitation and evapotranspiration. The approach used for modelling the water transport in the root zone has an impact on the predictions of the decline in root

  2. An IPSN research programme to resolve pending LOCA issues

    International Nuclear Information System (INIS)

    Mailliat, A.; Grandjean, C.; Clement, B.

    2001-01-01

    Studies performed in IPSN and elsewhere pointed out that high burnup may induce specific effects under LOCA conditions, especially those related with fuel relocation. Uncertainties exist regarding how much these effects might affect the late evolution of the accident transient and the associated safety issues. IPSN estimates that a better knowledge of specific phenomena is required in order to resolve the pending uncertainties related to LOCA criteria. IPSN is preparing the so called APRP-Irradie (High Burnup fuel LOCA) programme. One of the important aspect of this programme is in-pile experiments involving bundle geometries in the PHEBUS facility located at Cadarache, France. A feasibility study for such an experimental programme is underway and should provide soon, a finalized project including cost and schedule aspects. (authors)

  3. Harnessing the uncertainty monster: Putting quantitative constraints on the intergenerational social discount rate

    Science.gov (United States)

    Lewandowsky, Stephan; Freeman, Mark C.; Mann, Michael E.

    2017-09-01

    There is broad consensus among economists that unmitigated climate change will ultimately have adverse global economic consequences, that the costs of inaction will likely outweigh the cost of taking action, and that social planners should therefore put a price on carbon. However, there is considerable debate and uncertainty about the appropriate value of the social discount rate, that is the extent to which future damages should be discounted relative to mitigation costs incurred now. We briefly review the ethical issues surrounding the social discount rate and then report a simulation experiment that constrains the value of the discount rate by considering 4 sources of uncertainty and ambiguity: Scientific uncertainty about the extent of future warming, social uncertainty about future population and future economic development, political uncertainty about future mitigation trajectories, and ethical ambiguity about how much the welfare of future generations should be valued today. We compute a certainty-equivalent declining discount rate that accommodates all those sources of uncertainty and ambiguity. The forward (instantaneous) discount rate converges to a value near 0% by century's end and the spot (horizon) discount rate drops below 2% by 2100 and drops below previous estimates by 2070.

  4. The cost-effectiveness of cognitive behavioral therapy for bulimia nervosa in the Australian context.

    Science.gov (United States)

    Le, Long Khanh-Dao; Hay, Phillipa; Wade, Tracey; Touyz, Stephen; Mihalopoulos, Cathrine

    2017-12-01

    This study was to model the cost-effectiveness of specialist-delivered cognitive behavioral therapy for bulimia nervosa (CBT-BN) compared to no intervention within the Australian context. An illness-death model was developed to estimate the cost per disability-adjusted life-year (DALY) averted of CBT-BN over 2 years from the healthcare perspective. Target population was adults aged 18-65 years with BN. Results are reported as incremental cost-effectiveness ratios (ICER) in 2013 Australian dollars per DALY averted. Uncertainty and sensitivity analyses were conducted to test the robustness of results. Primary analysis indicated that CBT-BN was associated with greater DALY averted (0.10 DALY per person) and higher costs ($1,435 per person) than no intervention, resulting the mean ICER of $14,451 per DALY averted (95% uncertainty interval [UI]: $8,762 to $35,650). Uncertainty analysis indicated CBT-BN is 99% likely to be cost-effective at a threshold of $50,000 per DALY averted. Including the patients' time and travel costs resulted in the mean ICER of $18,858 per DALY averted (95% UI: $11,235 to $46,026). Sensitivity analysis indicated the intervention was not cost-effective if over 80% people discontinued treatment. Other analyses including a reduced time horizon, increased remission rates, and 4-month effect size of CBT-BN increases the ICERs but these ICERs remained well below under a threshold of $50,000 per DALY averted. This study has demonstrated that CBT-BN for adults with BN is a cost-effective treatment intervention. Further research is required to investigate the practicability of CBT-ED and the cost-effectiveness of other formats of CBT-BN delivery. © 2017 Wiley Periodicals, Inc.

  5. Technologies to Support Community-Dwelling Persons With Dementia: A Position Paper on Issues Regarding Development, Usability, Effectiveness and Cost-Effectiveness, Deployment, and Ethics.

    Science.gov (United States)

    Meiland, Franka; Innes, Anthea; Mountain, Gail; Robinson, Louise; van der Roest, Henriëtte; García-Casal, J Antonio; Gove, Dianne; Thyrian, Jochen René; Evans, Shirley; Dröes, Rose-Marie; Kelly, Fiona; Kurz, Alexander; Casey, Dympna; Szcześniak, Dorota; Dening, Tom; Craven, Michael P; Span, Marijke; Felzmann, Heike; Tsolaki, Magda; Franco-Martin, Manuel

    2017-01-16

    With the expected increase in the numbers of persons with dementia, providing timely, adequate, and affordable care and support is challenging. Assistive and health technologies may be a valuable contribution in dementia care, but new challenges may emerge. The aim of our study was to review the state of the art of technologies for persons with dementia regarding issues on development, usability, effectiveness and cost-effectiveness, deployment, and ethics in 3 fields of application of technologies: (1) support with managing everyday life, (2) support with participating in pleasurable and meaningful activities, and (3) support with dementia health and social care provision. The study also aimed to identify gaps in the evidence and challenges for future research. Reviews of literature and expert opinions were used in our study. Literature searches were conducted on usability, effectiveness and cost-effectiveness, and ethics using PubMed, Embase, CINAHL, and PsycINFO databases with no time limit. Selection criteria in our selected technology fields were reviews in English for community-dwelling persons with dementia. Regarding deployment issues, searches were done in Health Technology Assessment databases. According to our results, persons with dementia want to be included in the development of technologies; there is little research on the usability of assistive technologies; various benefits are reported but are mainly based on low-quality studies; barriers to deployment of technologies in dementia care were identified, and ethical issues were raised by researchers but often not studied. Many challenges remain such as including the target group more often in development, performing more high-quality studies on usability and effectiveness and cost-effectiveness, creating and having access to high-quality datasets on existing technologies to enable adequate deployment of technologies in dementia care, and ensuring that ethical issues are considered an important topic

  6. Emission trading schemes: potential revenue effects, compliance costs and overall tax policy issues

    International Nuclear Information System (INIS)

    Pope, Jeff; Owen, Anthony D.

    2009-01-01

    The case for the imposition of carbon (emission) taxes or tradable carbon permits in important tax jurisdictions is arguably strong, based upon the polluter pays principle first proposed by Pigou almost a century ago. This paper briefly reviews the arguments for and against these market-based instruments, and discusses their relative advantages and disadvantages in a practical context. In the case of Australia, the revenue effect of the proposed tradable carbon permits scheme is estimated to be A$11.5 billion in 2010-11. For comparison, this is roughly equivalent to a quarter of the revenue from the Goods and Services Tax. The paper focuses on three neglected aspects of climate change taxation discussion to date: how much tax revenue is likely to be raised, and the administrative and compliance costs of an emissions trading scheme, with particular reference to Australia. In discussing these issues, the paper draws upon selected and relevant international experience, particularly the European Union emissions trading scheme. The challenges of an emissions trading scheme, including integration with the existing tax system, particularly in an Australian context, are also discussed. The paper concludes by emphasising the key challenges and issues facing this 'ultimate externality' debate, particularly from a taxation policy perspective.

  7. The Cost-Effectiveness of Low-Cost Essential Antihypertensive Medicines for Hypertension Control in China: A Modelling Study.

    Directory of Open Access Journals (Sweden)

    Dongfeng Gu

    2015-08-01

    cardiovascular disease for secondary prevention was projected to be cost saving in the main simulation and 100% of probabilistic simulation results. Treating all hypertension for primary and secondary prevention would prevent about 800,000 cardiovascular disease events annually (95% uncertainty interval, 0.6 to 1.0 million and was borderline cost-effective incremental to treating only cardiovascular disease and stage two patients (2015 Int$13,000 per QALY gained [95% uncertainty interval, Int$10,000 to Int$18,000]. Of all one-way sensitivity analyses, assuming adherence to taking medications as low as 25%, high Shanghai drug costs, or low medication efficacy led to the most unfavorable results (treating all hypertension, about Int$47,000, Int$37,000, and Int$27,000 per QALY were gained, respectively. The strengths of this study were the use of a recent Chinese national health survey, vital statistics, health care costs, and cohort study outcomes data as model inputs and reliance on clinical-trial-based estimates of coronary heart disease and stroke risk reduction due to antihypertensive medication treatment. The limitations of the study were the use of several sources of data, limited clinical trial evidence for medication effectiveness and harms in the youngest and oldest age groups, lack of information about geographic and ethnic subgroups, lack of specific information about indirect costs borne by patients, and uncertainty about the future epidemiology of cardiovascular diseases in China.Expanded hypertension treatment has the potential to prevent about 800,000 cardiovascular disease events annually and be borderline cost-effective in China, provided low-cost essential antihypertensive medicines programs can be implemented.

  8. A cost-effectiveness comparison between early surgery and non-surgical approach for incidental papillary thyroid microcarcinoma.

    Science.gov (United States)

    Lang, Brian Hung-Hin; Wong, Carlos K H

    2015-09-01

    The issue of whether all incidental papillary thyroid microcarcinoma (PTMC) should be managed by early surgery (ES) has been questioned and there is a growing acceptance that a non-surgical approach (NSA) might be more appropriate. We conducted a cost-effectiveness analysis comparing the two strategies in managing incidental PTMC. Our base case was a hypothetical 40-year-old female diagnosed with a unifocal intra-thyroidal 9 mm PTMC. The PTMC was considered suitable for either strategy. A Markov decision tree model was constructed to compare the estimated cost-effectiveness between ES and NSA after 20 years. Outcome probabilities, utilities and costs were derived from the literature. The threshold for cost-effectiveness was set at USD 50,000/quality-adjusted life year (QALY). A further analysis was done for patients Sensitivity and threshold analyses were used to examine model uncertainty. Each patient who adopted NSA over ES cost an extra USD 682.54 but gained an additional 0.260 QALY. NSA was cost saving (i.e. less costly and more effective) up to 16 years from diagnosis and remained cost-effective from 17 years onward. In the sensitivity analysis, NSA remained cost-effective regardless of patient age (rates of progression, year cycle and discount rate. In the threshold analysis, none of the scenarios that could have changed the conclusion appeared clinically likely. For a selected group of incidental PTMC, adopting NSA was not only cost saving in the initial 16 years but also remained cost effective thereafter. This was irrespective of patient age, complication rate or rate of PTMC progression. © 2015 European Society of Endocrinology.

  9. Uncertainty and validation. Effect of model complexity on uncertainty estimates

    International Nuclear Information System (INIS)

    Elert, M.

    1996-09-01

    In the Model Complexity subgroup of BIOMOVS II, models of varying complexity have been applied to the problem of downward transport of radionuclides in soils. A scenario describing a case of surface contamination of a pasture soil was defined. Three different radionuclides with different environmental behavior and radioactive half-lives were considered: Cs-137, Sr-90 and I-129. The intention was to give a detailed specification of the parameters required by different kinds of model, together with reasonable values for the parameter uncertainty. A total of seven modelling teams participated in the study using 13 different models. Four of the modelling groups performed uncertainty calculations using nine different modelling approaches. The models used range in complexity from analytical solutions of a 2-box model using annual average data to numerical models coupling hydrology and transport using data varying on a daily basis. The complex models needed to consider all aspects of radionuclide transport in a soil with a variable hydrology are often impractical to use in safety assessments. Instead simpler models, often box models, are preferred. The comparison of predictions made with the complex models and the simple models for this scenario show that the predictions in many cases are very similar, e g in the predictions of the evolution of the root zone concentration. However, in other cases differences of many orders of magnitude can appear. One example is the prediction of the flux to the groundwater of radionuclides being transported through the soil column. Some issues that have come to focus in this study: There are large differences in the predicted soil hydrology and as a consequence also in the radionuclide transport, which suggests that there are large uncertainties in the calculation of effective precipitation and evapotranspiration. The approach used for modelling the water transport in the root zone has an impact on the predictions of the decline in root

  10. Risk Assessment and Decision-Making under Uncertainty in Tunnel and Underground Engineering

    Directory of Open Access Journals (Sweden)

    Yuanpu Xia

    2017-10-01

    Full Text Available The impact of uncertainty on risk assessment and decision-making is increasingly being prioritized, especially for large geotechnical projects such as tunnels, where uncertainty is often the main source of risk. Epistemic uncertainty, which can be reduced, is the focus of attention. In this study, the existing entropy-risk decision model is first discussed and analyzed, and its deficiencies are improved upon and overcome. Then, this study addresses the fact that existing studies only consider parameter uncertainty and ignore the influence of the model uncertainty. Here, focus is on the issue of model uncertainty and differences in risk consciousness with different decision-makers. The utility theory is introduced in the model. Finally, a risk decision model is proposed based on the sensitivity analysis and the tolerance cost, which can improve decision-making efficiency. This research can provide guidance or reference for the evaluation and decision-making of complex systems engineering problems, and indicate a direction for further research of risk assessment and decision-making issues.

  11. Reliability-Based Marginal Cost Pricing Problem Case with Both Demand Uncertainty and Travelers’ Perception Errors

    Directory of Open Access Journals (Sweden)

    Shaopeng Zhong

    2013-01-01

    Full Text Available Focusing on the first-best marginal cost pricing (MCP in a stochastic network with both travel demand uncertainty and stochastic perception errors within the travelers’ route choice decision processes, this paper develops a perceived risk-based stochastic network marginal cost pricing (PRSN-MCP model. Numerical examples based on an integrated method combining the moment analysis approach, the fitting distribution method, and the reliability measures are also provided to demonstrate the importance and properties of the proposed model. The main finding is that ignoring the effect of travel time reliability and travelers’ perception errors may significantly reduce the performance of the first-best MCP tolls, especially under high travelers’ confidence and network congestion levels. The analysis result could also enhance our understanding of (1 the effect of stochastic perception error (SPE on the perceived travel time distribution and the components of road toll; (2 the effect of road toll on the actual travel time distribution and its reliability measures; (3 the effect of road toll on the total network travel time distribution and its statistics; and (4 the effect of travel demand level and the value of reliability (VoR level on the components of road toll.

  12. Cost-effectiveness of laparoscopic versus open distal pancreatectomy for pancreatic cancer.

    Science.gov (United States)

    Gurusamy, Kurinchi Selvan; Riviere, Deniece; van Laarhoven, C J H; Besselink, Marc; Abu-Hilal, Mohammed; Davidson, Brian R; Morris, Steve

    2017-01-01

    A recent Cochrane review compared laparoscopic versus open distal pancreatectomy for people with for cancers of the body and tail of the pancreas and found that laparoscopic distal pancreatectomy may reduce the length of hospital stay. We compared the cost-effectiveness of laparoscopic distal pancreatectomy versus open distal pancreatectomy for pancreatic cancer. Model based cost-utility analysis estimating mean costs and quality-adjusted life years (QALYs) per patient from the perspective of the UK National Health Service. A decision tree model was constructed using probabilities, outcomes and cost data from published sources. A time horizon of 5 years was used. One-way and probabilistic sensitivity analyses were undertaken. The probabilistic sensitivity analysis showed that the incremental net monetary benefit was positive (£3,708.58 (95% confidence intervals (CI) -£9,473.62 to £16,115.69) but the 95% CI includes zero, indicating that there is significant uncertainty about the cost-effectiveness of laparoscopic distal pancreatectomy versus open distal pancreatectomy. The probability laparoscopic distal pancreatectomy was cost-effective compared to open distal pancreatectomy for pancreatic cancer was between 70% and 80% at the willingness-to-pay thresholds generally used in England (£20,000 to £30,000 per QALY gained). Results were sensitive to the survival proportions and the operating time. There is considerable uncertainty about whether laparoscopic distal pancreatectomy is cost-effective compared to open distal pancreatectomy for pancreatic cancer in the NHS setting.

  13. Deep uncertainty and broad heterogeneity in country-level social cost of carbon

    Science.gov (United States)

    Ricke, K.; Drouet, L.; Caldeira, K.; Tavoni, M.

    2017-12-01

    The social cost of carbon (SCC) is a commonly employed metric of the expected economic damages expected from carbon dioxide (CO2) emissions. Recent estimates of SCC range from approximately 10/tonne of CO2 to as much as 1000/tCO2, but these have been computed at the global level. While useful in an optimal policy context, a world-level approach obscures the heterogeneous geography of climate damages and vast differences in country-level contributions to global SCC, as well as climate and socio-economic uncertainties, which are much larger at the regional level. For the first time, we estimate country-level contributions to SCC using recent climate and carbon-cycle model projections, empirical climate-driven economic damage estimations, and information from the Shared Socio-economic Pathways. Central specifications show high global SCC values (median: 417 /tCO2, 66% confidence intervals: 168 - 793 /tCO2) with country-level contributions ranging from -11 (-8 - -14) /tCO2 to 86 (50 - 158) /tCO2. We quantify climate-, scenario- and economic damage- driven uncertainties associated with the calculated values of SCC. We find that while the magnitude of country-level social cost of carbon is highly uncertain, the relative positioning among countries is consistent. Countries incurring large fractions of the global cost include India, China, and the United States. The share of SCC distributed among countries is robust, indicating climate change winners and losers from a geopolitical perspective.

  14. Cost-effectiveness of nitrogen mitigation by alternative household wastewater management technologies.

    Science.gov (United States)

    Wood, Alison; Blackhurst, Michael; Hawkins, Troy; Xue, Xiaobo; Ashbolt, Nicholas; Garland, Jay

    2015-03-01

    Household wastewater, especially from conventional septic systems, is a major contributor to nitrogen pollution. Alternative household wastewater management technologies provide similar sewerage management services but their life cycle costs and nitrogen flow implications remain uncertain. This paper addresses two key questions: (1) what are the total costs, nitrogen mitigation potential, and cost-effectiveness of a range of conventional and alternative municipal wastewater treatment technologies, and (2) what uncertainties influence these outcomes and how can we improve our understanding of these technologies? We estimate a household nitrogen mass balance for various household wastewater treatment systems and combine this mass balance with life cycle cost assessment to calculate the cost-effectiveness of nitrogen mitigation, which we define as nitrogen removed from the local watershed. We apply our methods to Falmouth, MA, where failing septic systems have caused heightened eutrophication in local receiving water bodies. We find that flushing and dry (composting) urine-diversion toilets paired with conventional septic systems for greywater management demonstrate the lowest life cycle cost and highest cost-effectiveness (dollars per kilogram of nitrogen removed from the watershed). Composting toilets are also attractive options in some cases, particularly best-case nitrogen mitigation. Innovative/advanced septic systems designed for high-level nitrogen removal are cost-competitive options for newly constructed homes, except at their most expensive. A centralized wastewater treatment plant is the most expensive and least cost-effective option in all cases. Using a greywater recycling system with any treatment technology increases the cost without adding any nitrogen removal benefits. Sensitivity analysis shows that these results are robust considering a range of cases and uncertainties. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  15. Sensitivity of nuclear fuel-cycle cost to uncertainties in nuclear data. Final report

    International Nuclear Information System (INIS)

    Becker, M.; Harris, D.R.

    1980-11-01

    An improved capability for assessing the economic implications of uncertainties in nuclear data and methods on the power reactor fuel cycle was developed. This capability is applied to the sensitivity analysis of fuel-cycle cost with respect to changes in nuclear data and related computational methods. Broad group sensitivities for both a typical BWR and a PWR are determined under the assumption of a throwaway fuel cycle as well as for a scenario under which reprocessing is allowed. Particularly large dollar implications are found for the thermal and resonance cross sections of fissile and fertile materials. Sensitivities for the throwaway case are found to be significantly larger than for the recycle case. Constrained sensitivities obtained for cases in which information from critical experiments or other benchmarks is used in the design calculation to adjust a parameter such as anti ν are compared with unconstrained sensitivities. Sensitivities of various alternate fuel cycles were examined. These included the extended-burnup (18-month) LWR cycle, the mixed-oxide (plutonium) cycle, uranium-thorium and denatured uranium-thorium cycles, as well as CANDU-type reactor cycles. The importance of the thermal capture and fission cross sections of 239 Pu is shown to be very large in all cases. Detailed, energy dependent sensitivity profiles are provided for the thermal range (below 1.855 eV). Finally, sensitivity coefficients are combined with data uncertainties to determine the impact of such uncertainties on fuel-cycle cost parameters

  16. The economics of planning electricity transmission to accommodate renewables: Using two-stage optimisation to evaluate flexibility and the cost of disregarding uncertainty

    International Nuclear Information System (INIS)

    Weijde, Adriaan Hendrik van der; Hobbs, Benjamin F.

    2012-01-01

    Aggressive development of renewable electricity sources will require significant expansions in transmission infrastructure. We present a stochastic two-stage optimisation model that captures the multistage nature of transmission planning under uncertainty and use it to evaluate interregional grid reinforcements in Great Britain (GB). In our model, a proactive transmission planner makes investment decisions in two time periods, each time followed by a market response. Uncertainty is represented by economic, technology, and regulatory scenarios, and first-stage investments must be made before it is known which scenario will occur. The model allows us to identify expected cost-minimising first-stage investments, as well as estimate the value of information, the cost of ignoring uncertainty, and the value of flexibility. Our results show that ignoring risk in planning transmission for renewables has quantifiable economic consequences, and that considering uncertainty can yield decisions that have lower expected costs than traditional deterministic planning methods. In the GB case, the value of information and cost of disregarding uncertainty in transmission planning were of the same order of magnitude (approximately £100 M, in present worth terms). Further, the best plan under a risk-neutral decision criterion can differ from the best under risk-aversion. Finally, a traditional sensitivity analysis-based robustness analysis also yields different results than the stochastic model, although the former's expected cost is not much higher.

  17. Professional oral health care for preventing nursing home-acquired pneumonia: A cost-effectiveness and value of information analysis.

    Science.gov (United States)

    Schwendicke, Falk; Stolpe, Michael; Müller, Frauke

    2017-12-01

    Professional oral health care (POHC) prevents nursing home-acquired pneumonia (NHAP) and its related mortality. We assessed the cost-effectiveness of POHC versus no POHC (nPOHC) and the monetary value of eliminating uncertainty by future research. A German public-private payer perspective was adopted. A Markov model was used, following long-term care residents from admission to death. Cost-effectiveness was estimated as Euro/disability-adjusted life year (DALY) using Monte Carlo microsimulations. Value-of-information analyses were performed. The willingness-to-pay threshold/DALY was assumed to be 66% (range 50%-100%) of per-capita gross domestic product (GDP). nPOHC was less costly (€3,024) but also less effective (0.89 DALYs) than POHC (€10,249, 0.55 DALYs). For most presumed payers, POHC was cost-effective. The cost-effectiveness of POHC was higher in smokers, underweight or pulmonary disease patients. Eliminating uncertainty about the NHAP costs, NHAP incidence/mortality, and POHC effectiveness would result in an expected net value of 47 million €/year (and even higher values at lower GDP thresholds), and is likely to decrease with time. Within the chosen setting and on the basis of current evidence, POHC was cost-effective. Given the detected uncertainty, further research seems warranted. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  18. Cost-effectiveness of canine vaccination to prevent human rabies in rural Tanzania.

    Science.gov (United States)

    Fitzpatrick, Meagan C; Hampson, Katie; Cleaveland, Sarah; Mzimbiri, Imam; Lankester, Felix; Lembo, Tiziana; Meyers, Lauren A; Paltiel, A David; Galvani, Alison P

    2014-01-21

    The annual mortality rate of human rabies in rural Africa is 3.6 deaths per 100 000 persons. Rabies can be prevented with prompt postexposure prophylaxis, but this is costly and often inaccessible in rural Africa. Because 99% of human exposures occur through rabid dogs, canine vaccination also prevents transmission of rabies to humans. To evaluate the cost-effectiveness of rabies control through annual canine vaccination campaigns in rural sub-Saharan Africa. We model transmission dynamics in dogs and wildlife and assess empirical uncertainty in the biological variables to make probability-based evaluations of cost-effectiveness. Epidemiologic variables from a contact-tracing study and literature and cost data from ongoing vaccination campaigns. Two districts of rural Tanzania: Ngorongoro and Serengeti. 10 years. Health policymaker. Vaccination coverage ranging from 0% to 95% in increments of 5%. Life-years for health outcomes and 2010 U.S. dollars for economic outcomes. Annual canine vaccination campaigns were very cost-effective in both districts compared with no canine vaccination. In Serengeti, annual campaigns with as much as 70% coverage were cost-saving. Across a wide range of variable assumptions and levels of societal willingness to pay for life-years, the optimal vaccination coverage for Serengeti was 70%. In Ngorongoro, although optimal coverage depended on willingness to pay, vaccination campaigns were always cost-effective and lifesaving and therefore preferred. Canine vaccination was very cost-effective in both districts, but there was greater uncertainty about the optimal coverage in Ngorongoro. Annual canine rabies vaccination campaigns conferred extraordinary value and dramatically reduced the health burden of rabies. National Institutes of Health.

  19. Effects of slim holes on hydrothermal exploration costs

    International Nuclear Information System (INIS)

    Entingh, D.; Petty, S.

    1992-01-01

    This paper estimates hydrothermal exploration costs and the effects that using slim holes could have on those costs using a computer code developed for the US-DOE. The primary goal of exploration is to generate decision driving information about particular geothermal reservoirs. Compared to today's exploration strategies, the main effect of using slim holes would be to reduce the cost of exploration by about 40 percent. Slim hole exploration does not reduce the overall cost of electricity by much; however, the cost burden is shifted later in the project when outside financing is more likely. The reduced costs of slim holes may also encourage developers to drill more holes that better characterize the reservoir, thus reducing long term reservoir risk. The cost of power could then be cut as much as six percent and project financial risks related to reservoir uncertainties could be reduced by up to one quarter. In order to realize these improvements, the amount of reservoir information recovered from small diameter bore holes needs to be significantly increased

  20. Risk management of energy system for identifying optimal power mix with financial-cost minimization and environmental-impact mitigation under uncertainty

    International Nuclear Information System (INIS)

    Nie, S.; Li, Y.P.; Liu, J.; Huang, Charley Z.

    2017-01-01

    An interval-stochastic risk management (ISRM) method is launched to control the variability of the recourse cost as well as to capture the notion of risk in stochastic programming. The ISRM method can examine various policy scenarios that are associated with economic penalties under uncertainties presented as probability distributions and interval values. An ISRM model is then formulated to identify the optimal power mix for the Beijing's energy system. Tradeoffs between risk and cost are evaluated, indicating any change in targeted cost and risk level would yield different expected costs. Results reveal that the inherent uncertainty of system components and risk attitude of decision makers have significant effects on the city's energy-supply and electricity-generation schemes as well as system cost and probabilistic penalty. Results also disclose that import electricity as a recourse action to compensate the local shortage would be enforced. The import electricity would increase with a reduced risk level; under every risk level, more electricity would be imported with an increased demand. The findings can facilitate the local authority in identifying desired strategies for the city's energy planning and management in association with financial-cost minimization and environmental-impact mitigation. - Highlights: • Interval-stochastic risk management method is launched to identify optimal power mix. • It is advantageous in capturing the notion of risk in stochastic programming. • Results reveal that risk attitudes can affect optimal power mix and financial cost. • Developing renewable energies would enhance the sustainability of energy management. • Import electricity as an action to compensate the local shortage would be enforced.

  1. Cost-effectiveness analysis alongside a pilot study of prophylactic negative pressure wound therapy.

    Science.gov (United States)

    Heard, Christopher; Chaboyer, Wendy; Anderson, Vinah; Gillespie, Brigid M; Whitty, Jennifer A

    2017-02-01

    Negative pressure wound therapy (NPWT) is increasingly used prophylactically following surgery despite limited evidence of clinical or cost-effectiveness. To evaluate whether NPWT is cost-effective compared to standard care, for the prevention of surgical site infection (SSI) in obese women undergoing elective caesarean section, and inform development of a larger trial. An economic evaluation was conducted alongside a pilot randomised controlled trial at one Australian hospital, in which women were randomised to NPWT (n = 44) or standard care (n = 43). A public health care provider perspective and time horizon to four weeks post-discharge was adopted. Cost-effectiveness assessment was based on incremental cost per SSI prevented and per quality-adjusted life year (QALY) gained. Patients receiving NPWT each received health care costing AU$5887 (±1038) and reported 0.069 (±0.010) QALYs compared to AU$5754 (±1484) and 0.066 (±0.010) QALYs for patients receiving standard care. NPWT may be slightly more costly and more effective than standard care, with estimated incremental cost-effectiveness ratios (ICERs) of AU$1347 (95%CI dominant- $41,873) per SSI prevented and AU$42,340 (95%CI dominant- $884,019) per QALY gained. However, there was considerable uncertainty around these estimates. NPWT may be cost-effective in the prophylactic treatment of surgical wounds following elective caesarean section in obese women. Larger trials could clarify the cost-effectiveness of NPWT as a prophylactic treatment for SSI. Sensitive capture of QALYs and cost offsets will be important given the high level of uncertainty around the point estimate cost-effectiveness ratio which was close to conventional thresholds. ACTRN12612000171819. Copyright © 2016 Tissue Viability Society. Published by Elsevier Ltd. All rights reserved.

  2. Uncertainties in early-stage capital cost estimation of process design – a case study on biorefinery design

    DEFF Research Database (Denmark)

    Cheali, Peam; Gernaey, Krist; Sin, Gürkan

    2015-01-01

    Capital investment, next to the product demand, sales, and production costs, is one of the key metrics commonly used for project evaluation and feasibility assessment. Estimating the investment costs of a new product/process alternative during early-stage design is a challenging task, which......) the Monte Carlo technique as an error propagation method based on expert input when cost data are not available. Four well-known models for early-stage cost estimation are reviewed and analyzed using the methodology. The significance of uncertainties of cost data for early-stage process design...

  3. External costs of PM2.5 pollution in Beijing, China: Uncertainty analysis of multiple health impacts and costs

    DEFF Research Database (Denmark)

    Hao, Yin; Pizzol, Massimo; Xu, Linyu

    2017-01-01

    Some cities in China are facing serious air pollution problems including high concentrations of particles, SO2 and NOx. Exposure to PM2.5, one of the primary air pollutants in many cities in China, is highly correlated with various adverse health impacts and ultimately represents a cost for society....... The aim of this study is to assess health impacts and external costs related to PM2.5 pollution in Beijing, China with different baseline concentrations and valuation methods. The idea is to provide a reasonable estimate of the total health impacts and external cost due to PM2.5 pollution, as well...... as a quantification of the relevant uncertainty. PM2.5 concentrations were retrieved for the entire 2012 period in 16 districts of Beijing. The various PM2.5 related health impacts were identified and classified to avoid double counting. Exposure-response coefficients were then obtained from literature. Both...

  4. Derivative-free optimization under uncertainty applied to costly simulators

    International Nuclear Information System (INIS)

    Pauwels, Benoit

    2016-01-01

    The modeling of complex phenomena encountered in industrial issues can lead to the study of numerical simulation codes. These simulators may require extensive execution time (from hours to days), involve uncertain parameters and even be intrinsically stochastic. Importantly within the context of simulation-based optimization, the derivatives of the outputs with respect to the inputs may be inexistent, inaccessible or too costly to approximate reasonably. This thesis is organized in four chapters. The first chapter discusses the state of the art in derivative-free optimization and uncertainty modeling. The next three chapters introduce three independent - although connected - contributions to the field of derivative-free optimization in the presence of uncertainty. The second chapter addresses the emulation of costly stochastic simulation codes - stochastic in the sense simulations run with the same input parameters may lead to distinct outputs. Such was the matter of the CODESTOCH project carried out at the Summer mathematical research center on scientific computing and its applications (CEMRACS) during the summer of 2013, together with two Ph.D. students from Electricity of France (EDF) and the Atomic Energy and Alternative Energies Commission (CEA). We designed four methods to build emulators for functions whose values are probability density functions. These methods were tested on two toy functions and applied to industrial simulation codes concerned with three complex phenomena: the spatial distribution of molecules in a hydrocarbon system (IFPEN), the life cycle of large electric transformers (EDF) and the repercussions of a hypothetical accidental in a nuclear plant (CEA). Emulation was a preliminary process towards optimization in the first two cases. In the third chapter we consider the influence of inaccurate objective function evaluations on direct search - a classical derivative-free optimization method. In real settings inaccuracy may never vanish

  5. Comparison of the effect of hazard and response/fragility uncertainties on core melt probability uncertainty

    International Nuclear Information System (INIS)

    Mensing, R.W.

    1985-01-01

    This report proposes a method for comparing the effects of the uncertainty in probabilistic risk analysis (PRA) input parameters on the uncertainty in the predicted risks. The proposed method is applied to compare the effect of uncertainties in the descriptions of (1) the seismic hazard at a nuclear power plant site and (2) random variations in plant subsystem responses and component fragility on the uncertainty in the predicted probability of core melt. The PRA used is that developed by the Seismic Safety Margins Research Program

  6. Potential effects of organizational uncertainty on safety

    Energy Technology Data Exchange (ETDEWEB)

    Durbin, N.E. [MPD Consulting Group, Kirkland, WA (United States); Lekberg, A. [Swedish Nuclear Power Inspectorate, Stockholm (Sweden); Melber, B.D. [Melber Consulting, Seattle WA (United States)

    2001-12-01

    When organizations face significant change - reorganization, mergers, acquisitions, down sizing, plant closures or decommissioning - both the organizations and the workers in those organizations experience significant uncertainty about the future. This uncertainty affects the organization and the people working in the organization - adversely affecting morale, reducing concentration on safe operations, and resulting in the loss of key staff. Hence, organizations, particularly those using high risk technologies, which are facing significant change need to consider and plan for the effects of organizational uncertainty on safety - as well as planning for other consequences of change - technical, economic, emotional, and productivity related. This paper reviews some of what is known about the effects of uncertainty on organizations and individuals, discusses the potential consequences of uncertainty on organizational and individual behavior, and presents some of the implications for safety professionals.

  7. Potential effects of organizational uncertainty on safety

    International Nuclear Information System (INIS)

    Durbin, N.E.; Lekberg, A.; Melber, B.D.

    2001-12-01

    When organizations face significant change - reorganization, mergers, acquisitions, down sizing, plant closures or decommissioning - both the organizations and the workers in those organizations experience significant uncertainty about the future. This uncertainty affects the organization and the people working in the organization - adversely affecting morale, reducing concentration on safe operations, and resulting in the loss of key staff. Hence, organizations, particularly those using high risk technologies, which are facing significant change need to consider and plan for the effects of organizational uncertainty on safety - as well as planning for other consequences of change - technical, economic, emotional, and productivity related. This paper reviews some of what is known about the effects of uncertainty on organizations and individuals, discusses the potential consequences of uncertainty on organizational and individual behavior, and presents some of the implications for safety professionals

  8. A systematic framework for effective uncertainty assessment of severe accident calculations; Hybrid qualitative and quantitative methodology

    International Nuclear Information System (INIS)

    Hoseyni, Seyed Mohsen; Pourgol-Mohammad, Mohammad; Tehranifard, Ali Abbaspour; Yousefpour, Faramarz

    2014-01-01

    This paper describes a systematic framework for characterizing important phenomena and quantifying the degree of contribution of each parameter to the output in severe accident uncertainty assessment. The proposed methodology comprises qualitative as well as quantitative phases. The qualitative part so called Modified PIRT, being a robust process of PIRT for more precise quantification of uncertainties, is a two step process for identifying and ranking based on uncertainty importance in severe accident phenomena. In this process identified severe accident phenomena are ranked according to their effect on the figure of merit and their level of knowledge. Analytical Hierarchical Process (AHP) serves here as a systematic approach for severe accident phenomena ranking. Formal uncertainty importance technique is used to estimate the degree of credibility of the severe accident model(s) used to represent the important phenomena. The methodology uses subjective justification by evaluating available information and data from experiments, and code predictions for this step. The quantitative part utilizes uncertainty importance measures for the quantification of the effect of each input parameter to the output uncertainty. A response surface fitting approach is proposed for estimating associated uncertainties with less calculation cost. The quantitative results are used to plan in reducing epistemic uncertainty in the output variable(s). The application of the proposed methodology is demonstrated for the ACRR MP-2 severe accident test facility. - Highlights: • A two stage framework for severe accident uncertainty analysis is proposed. • Modified PIRT qualitatively identifies and ranks uncertainty sources more precisely. • Uncertainty importance measure quantitatively calculates effect of each uncertainty source. • Methodology is applied successfully on ACRR MP-2 severe accident test facility

  9. Portfolio theory and cost-effectiveness analysis: a further discussion.

    Science.gov (United States)

    Sendi, Pedram; Al, Maiwenn J; Rutten, Frans F H

    2004-01-01

    Portfolio theory has been suggested as a means to improve the risk-return characteristics of investments in health-care programs through diversification when costs and effects are uncertain. This approach is based on the assumption that the investment proportions are not subject to uncertainty and that the budget can be invested in toto in health-care programs. In the present paper we develop an algorithm that accounts for the fact that investment proportions in health-care programs may be uncertain (due to the uncertainty associated with costs) and limited (due to the size of the programs). The initial budget allocation across programs may therefore be revised at the end of the investment period to cover the extra costs of some programs with the leftover budget of other programs in the portfolio. Once the total budget is equivalent to or exceeds the expected costs of the programs in the portfolio, the initial budget allocation policy does not impact the risk-return characteristics of the combined portfolio, i.e., there is no benefit from diversification anymore. The applicability of portfolio methods to improve the risk-return characteristics of investments in health care is limited to situations where the available budget is much smaller than the expected costs of the programs to be funded.

  10. Cost-effectiveness of rotavirus vaccination in Albania.

    Science.gov (United States)

    Ahmeti, Albana; Preza, Iria; Simaku, Artan; Nelaj, Erida; Clark, Andrew David; Felix Garcia, Ana Gabriela; Lara, Carlos; Hoestlandt, Céline; Blau, Julia; Bino, Silvia

    2015-05-07

    Rotavirus vaccines have been introduced in several European countries but can represent a considerable cost, particularly for countries that do not qualify for any external financial support. This study aimed to evaluate the cost-effectiveness of introducing rotavirus vaccination into Albania's national immunization program and to inform national decision-making by improving national capacity to conduct economic evaluations of new vaccines. The TRIVAC model was used to assess vaccine impact and cost-effectiveness. The model estimated health and economic outcomes attributed to 10 successive vaccinated birth cohorts (2013-2022) from a government and societal perspective. Epidemiological and economic data used in the model were based on national cost studies, and surveillance data, as well as estimates from the scientific literature. Cost-effectiveness was estimated for both the monovalent (RV1) and pentavalent vaccines (RV5). A multivariate scenario analysis (SA) was performed to evaluate the uncertainty around the incremental cost-effectiveness ratios (ICERs). With 3% discounting of costs and health benefits over the period 2013-2022, rotavirus vaccination in Albania could avert 51,172 outpatient visits, 14,200 hospitalizations, 27 deaths, 950 disability-adjusted life-years (DALYs), and gain 801 life-years. When both vaccines were compared to no vaccination, the discounted cost per DALY averted was US$ 2008 for RV1 and US$ 5047 for RV5 from a government perspective. From the societal perspective the values were US$ 517 and US$ 3556, respectively. From both the perspectives, the introduction of rotavirus vaccine to the Albanian immunization schedule is either cost-effective or highly cost-effective for a range of plausible scenarios. In most scenarios, including the base-case scenario, the discounted cost per DALY averted was less than three times the gross domestic product (GDP) per capita. However, rotavirus vaccination was not cost-effective when rotavirus cases

  11. Improving Maternal Care through a State-Wide Health Insurance Program: A Cost and Cost-Effectiveness Study in Rural Nigeria.

    Science.gov (United States)

    Gomez, Gabriela B; Foster, Nicola; Brals, Daniella; Nelissen, Heleen E; Bolarinwa, Oladimeji A; Hendriks, Marleen E; Boers, Alexander C; van Eck, Diederik; Rosendaal, Nicole; Adenusi, Peju; Agbede, Kayode; Akande, Tanimola M; Boele van Hensbroek, Michael; Wit, Ferdinand W; Hankins, Catherine A; Schultsz, Constance

    2015-01-01

    While the Nigerian government has made progress towards the Millennium Development Goals, further investments are needed to achieve the targets of post-2015 Sustainable Development Goals, including Universal Health Coverage. Economic evaluations of innovative interventions can help inform investment decisions in resource-constrained settings. We aim to assess the cost and cost-effectiveness of maternal care provided within the new Kwara State Health Insurance program (KSHI) in rural Nigeria. We used a decision analytic model to simulate a cohort of pregnant women. The primary outcome is the incremental cost effectiveness ratio (ICER) of the KSHI scenario compared to the current standard of care. Intervention cost from a healthcare provider perspective included service delivery costs and above-service level costs; these were evaluated in a participating hospital and using financial records from the managing organisations, respectively. Standard of care costs from a provider perspective were derived from the literature using an ingredient approach. We generated 95% credibility intervals around the primary outcome through probabilistic sensitivity analysis (PSA) based on a Monte Carlo simulation. We conducted one-way sensitivity analyses across key model parameters and assessed the sensitivity of our results to the performance of the base case separately through a scenario analysis. Finally, we assessed the sustainability and feasibility of this program's scale up within the State's healthcare financing structure through a budget impact analysis. The KSHI scenario results in a health benefit to patients at a higher cost compared to the base case. The mean ICER (US$46.4/disability-adjusted life year averted) is considered very cost-effective compared to a willingness-to-pay threshold of one gross domestic product per capita (Nigeria, US$ 2012, 2,730). Our conclusion was robust to uncertainty in parameters estimates (PSA: median US$49.1, 95% credible interval 21

  12. Improving Maternal Care through a State-Wide Health Insurance Program: A Cost and Cost-Effectiveness Study in Rural Nigeria.

    Directory of Open Access Journals (Sweden)

    Gabriela B Gomez

    Full Text Available While the Nigerian government has made progress towards the Millennium Development Goals, further investments are needed to achieve the targets of post-2015 Sustainable Development Goals, including Universal Health Coverage. Economic evaluations of innovative interventions can help inform investment decisions in resource-constrained settings. We aim to assess the cost and cost-effectiveness of maternal care provided within the new Kwara State Health Insurance program (KSHI in rural Nigeria.We used a decision analytic model to simulate a cohort of pregnant women. The primary outcome is the incremental cost effectiveness ratio (ICER of the KSHI scenario compared to the current standard of care. Intervention cost from a healthcare provider perspective included service delivery costs and above-service level costs; these were evaluated in a participating hospital and using financial records from the managing organisations, respectively. Standard of care costs from a provider perspective were derived from the literature using an ingredient approach. We generated 95% credibility intervals around the primary outcome through probabilistic sensitivity analysis (PSA based on a Monte Carlo simulation. We conducted one-way sensitivity analyses across key model parameters and assessed the sensitivity of our results to the performance of the base case separately through a scenario analysis. Finally, we assessed the sustainability and feasibility of this program's scale up within the State's healthcare financing structure through a budget impact analysis. The KSHI scenario results in a health benefit to patients at a higher cost compared to the base case. The mean ICER (US$46.4/disability-adjusted life year averted is considered very cost-effective compared to a willingness-to-pay threshold of one gross domestic product per capita (Nigeria, US$ 2012, 2,730. Our conclusion was robust to uncertainty in parameters estimates (PSA: median US$49.1, 95% credible

  13. Costs, quality of life and cost-effectiveness of arthroscopic and open repair for rotator cuff tears: an economic evaluation alongside the UKUFF trial.

    Science.gov (United States)

    Murphy, J; Gray, A; Cooper, C; Cooper, D; Ramsay, C; Carr, A

    2016-12-01

    A trial-based comparison of the use of resources, costs and quality of life outcomes of arthroscopic and open surgical management for rotator cuff tears in the United Kingdom NHS was performed using data from the United Kingdom Rotator Cuff Study (UKUFF) randomised controlled trial. Using data from 273 patients, healthcare-related use of resources, costs and quality-adjusted life years (QALYs) were estimated at 12 months and 24 months after surgery on an intention-to-treat basis with adjustment for covariates. Uncertainty about the incremental cost-effectiveness ratio for arthroscopic versus open management at 24 months of follow-up was incorporated using bootstrapping. Multiple imputation methods were used to deal with missing data. There were no significant differences between the arthroscopic and open groups in terms of total mean use and cost of resources or QALYs at any time post-operatively. Open management dominated arthroscopic management in 59.8% of bootstrapped cost and effect differences. The probability that arthroscopic management was cost-effective compared with open management at a willingness-to-pay threshold of £20 000 per QALY gained was 20.9%. There was no significant overall difference in the use or cost of resources or quality of life between arthroscopic and open management in the trial. There was uncertainty about which strategy was most cost-effective. Cite this article: Bone Joint J 2016;98-B:1648-55. ©2016 Gray et al.

  14. US firms still restructuring, cutting costs under oil price uncertainty

    International Nuclear Information System (INIS)

    Koen, A.D.

    1994-01-01

    Despite more than a decade of downsizing, continuing uncertainty in oil markets is forcing US petroleum companies into another round of cutting and restructuring operations. Wellhead gas prices in the US, although still volatile, in the past 2 years have risen to levels adequate to allow profits for most producers in that sector. Higher gas reserves valuations have strengthened producers' overall balance sheets. But the slide in oil prices from the middle of fourth quarter 1993 until the recent upswing the past month has withered producers' financial performances and reserves values. With little prospect of significantly higher oil prices anytime soon, US companies feel they have little choice but to continue pressing cost cutting moves in order to sustain profits in the near term while at the same time earnings a higher return on investment in the long term. Petroleum company executives are overlooking almost no operating or investment strategy thought capable of bolstering the bottom line. Because no two US oil and gas companies are alike, each profit protection plan is a unique mix of similar solutions. Oil and gas production companies most often try to lower operating costs by vigorously selling noncore properties or business units and reducing staff. The paper discusses measures taken by oil and gas companies to lower costs

  15. Climate policy uncertainty and investment risk

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-06-21

    Our climate is changing. This is certain. Less certain, however, is the timing and magnitude of climate change, and the cost of transition to a low-carbon world. Therefore, many policies and programmes are still at a formative stage, and policy uncertainty is very high. This book identifies how climate change policy uncertainty may affect investment behaviour in the power sector. For power companies, where capital stock is intensive and long-lived, those risks rank among the biggest and can create an incentive to delay investment. Our analysis results show that the risk premiums of climate change uncertainty can add 40% of construction costs of the plant for power investors, and 10% of price surcharges for the electricity end-users. This publication tells what can be done in policy design to reduce these costs. Incorporating the results of quantitative analysis, this publication also shows the sensitivity of different power sector investment decisions to different risks. It compares the effects of climate policy uncertainty with energy market uncertainty, showing the relative importance of these sources of risk for different technologies in different market types. Drawing on extensive consultation with power companies and financial investors, it also assesses the implications for policy makers, allowing the key messages to be transferred into policy designs. This book is a useful tool for governments to improve climate policy mechanisms and create more certainty for power investors.

  16. Probabilistic cost estimating of nuclear power plant construction projects

    International Nuclear Information System (INIS)

    Finch, W.C.; Perry, L.W.; Postula, F.D.

    1978-01-01

    This paper shows how to identify and isolate cost accounts by developing probability trees down to component levels as justified by value and cost uncertainty. Examples are given of the procedure for assessing uncertainty in all areas contributing to cost: design, factory equipment pricing, and field labor and materials. The method of combining these individual uncertainties is presented so that the cost risk can be developed for components, systems and the total plant construction project. Formats which enable management to use the probabilistic cost estimate information for business planning and risk control are illustrated. Topics considered include code estimate performance, cost allocation, uncertainty encoding, probabilistic cost distributions, and interpretation. Effective cost control of nuclear power plant construction projects requires insight into areas of greatest cost uncertainty and a knowledge of the factors which can cause costs to vary from the single value estimates. It is concluded that probabilistic cost estimating can provide the necessary assessment of uncertainties both as to the cause and the consequences

  17. The role of social cost-benefit analysis in societal decision-making under large uncertainties with application to robbery at a cash depot

    International Nuclear Information System (INIS)

    Jones-Lee, M.; Aven, T.

    2009-01-01

    Social cost-benefit analysis is a well-established method for guiding decisions about safety investments, particularly in situations in which it is possible to make accurate predictions of future performance. However, its direct applicability to situations involving large degrees of uncertainty is less obvious and this raises the question of the extent to which social cost-benefit analysis can provide a useful input to the decision framework that has been explicitly developed to deal with safety decisions in which uncertainty is a major factor, namely risk analysis. This is the main focus of the arguments developed in this paper. In particular, we provide new insights by examining the fundamentals of both approaches and our principal conclusion is that social cost-benefit analysis and risk analysis represent complementary input bases to the decision-making process, and even in the case of large uncertainties social cost-benefit analysis may provide very useful decision support. What is required is the establishment of a proper contextual framework which structures and gives adequate weight to the uncertainties. An application to the possibility of a robbery at a cash depot is examined as a practical example.

  18. Uncertainty Analysis with Considering Resonance Self-shielding Effect

    Energy Technology Data Exchange (ETDEWEB)

    Han, Tae Young [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    If infinitely diluted multi-group cross sections were used for the sensitivity, the covariance data from the evaluated nuclear data library (ENDL) was directly applied. However, in case of using a self-shielded multi-group cross section, the covariance data should be corrected considering self-shielding effect. Usually, implicit uncertainty can be defined as the uncertainty change by the resonance self-shielding effect as described above. MUSAD ( Modules of Uncertainty and Sensitivity Analysis for DeCART ) has been developed for a multiplication factor and cross section uncertainty based on the generalized perturbation theory and it, however, can only quantify the explicit uncertainty by the self-shielded multi-group cross sections without considering the implicit effect. Thus, this paper addresses the implementation of the implicit uncertainty analysis module into the code and the numerical results for the verification are provided. The implicit uncertainty analysis module has been implemented into MUSAD based on infinitely-diluted cross section-based consistent method. The verification calculation was performed on MHTGR 350 Ex.I-1a and the differences with McCARD result decrease from 40% to 1% in CZP case and 3% in HFP case. From this study, it is expected that MUSAD code can reasonably produce the complete uncertainty on VHTR or LWR where the resonance self-shielding effect should be significantly considered.

  19. Uncertainty Analysis with Considering Resonance Self-shielding Effect

    International Nuclear Information System (INIS)

    Han, Tae Young

    2016-01-01

    If infinitely diluted multi-group cross sections were used for the sensitivity, the covariance data from the evaluated nuclear data library (ENDL) was directly applied. However, in case of using a self-shielded multi-group cross section, the covariance data should be corrected considering self-shielding effect. Usually, implicit uncertainty can be defined as the uncertainty change by the resonance self-shielding effect as described above. MUSAD ( Modules of Uncertainty and Sensitivity Analysis for DeCART ) has been developed for a multiplication factor and cross section uncertainty based on the generalized perturbation theory and it, however, can only quantify the explicit uncertainty by the self-shielded multi-group cross sections without considering the implicit effect. Thus, this paper addresses the implementation of the implicit uncertainty analysis module into the code and the numerical results for the verification are provided. The implicit uncertainty analysis module has been implemented into MUSAD based on infinitely-diluted cross section-based consistent method. The verification calculation was performed on MHTGR 350 Ex.I-1a and the differences with McCARD result decrease from 40% to 1% in CZP case and 3% in HFP case. From this study, it is expected that MUSAD code can reasonably produce the complete uncertainty on VHTR or LWR where the resonance self-shielding effect should be significantly considered

  20. Impacts of Korea's Exchange Rate Uncertainty on Exports

    Directory of Open Access Journals (Sweden)

    Kwon Sik Kim

    2003-12-01

    Full Text Available This paper examines the effects of two types of uncertainty related to the real effective exchange rate (REER in Korea for export trends. To decompose uncertainties into two types of component, I propose an advanced generalized Markov switching model, as developed by Hamilton (1989 and then expanded by Kim and Kim (1996. The proposed model is useful in uncovering two sources of uncertainty: the permanent component of REER and the purely transitory component. I think that the two types of uncertainties have a different effect on export trends in Korea. The transitory component of REER has no effect on the export trend at 5-percent significance, but the permanent component has an effect at this level. In addition, the degree of uncertainty, consisting of low, medium and high uncertainty in the permanent component, and low, medium and high uncertainty in transitory component of REER, also has different effects on export trends in Korea. Only high uncertainty in permanent components effects export trends. The results show that when the policy authority intends to prevent the shrinkage of exports due to the deepening of uncertainties in the foreign exchange market, the economic impacts of its intervention could appear differently according to the characteristics and degree of the uncertainties. Therefore, they imply that its economic measures, which could not grasp the sources of uncertainties properly, may even bring economic costs.

  1. The costs of uncertainty: regulating health and safety in the Canadian uranium industry

    International Nuclear Information System (INIS)

    Robinson, I.

    1982-04-01

    Federalism, and particularly federal/provincial jurisdictional relationships, have led to considerable uncertainty in the regulation of occupational health and safety and of environmental protection in the Canadian uranium mining industry. The two principal uranium producing provinces in Canada are Saskatchewan and Ontario. Since 1978, in an attempt to avoid constitutional issues, both these provinces and the federal government as well have proceeded unilaterally with health and safety reforms for the industry. In Saskatchewan this has resulted in areas of overlapping jurisdiction, which have led to uncertainty over the legal enforceability of the provincial regulations. In Ontario, the province has left significant gaps in the protection of both workers and the environment. Little progress can be expected in eliminating these gaps and overlaps until the current administrative and jurisdictional arrangements are understood

  2. Clinical benefits, costs, and cost-effectiveness of neonatal intensive care in Mexico.

    Directory of Open Access Journals (Sweden)

    Jochen Profit

    2010-12-01

    Full Text Available Neonatal intensive care improves survival, but is associated with high costs and disability amongst survivors. Recent health reform in Mexico launched a new subsidized insurance program, necessitating informed choices on the different interventions that might be covered by the program, including neonatal intensive care. The purpose of this study was to estimate the clinical outcomes, costs, and cost-effectiveness of neonatal intensive care in Mexico.A cost-effectiveness analysis was conducted using a decision analytic model of health and economic outcomes following preterm birth. Model parameters governing health outcomes were estimated from Mexican vital registration and hospital discharge databases, supplemented with meta-analyses and systematic reviews from the published literature. Costs were estimated on the basis of data provided by the Ministry of Health in Mexico and World Health Organization price lists, supplemented with published studies from other countries as needed. The model estimated changes in clinical outcomes, life expectancy, disability-free life expectancy, lifetime costs, disability-adjusted life years (DALYs, and incremental cost-effectiveness ratios (ICERs for neonatal intensive care compared to no intensive care. Uncertainty around the results was characterized using one-way sensitivity analyses and a multivariate probabilistic sensitivity analysis. In the base-case analysis, neonatal intensive care for infants born at 24-26, 27-29, and 30-33 weeks gestational age prolonged life expectancy by 28, 43, and 34 years and averted 9, 15, and 12 DALYs, at incremental costs per infant of US$11,400, US$9,500, and US$3,000, respectively, compared to an alternative of no intensive care. The ICERs of neonatal intensive care at 24-26, 27-29, and 30-33 weeks were US$1,200, US$650, and US$240, per DALY averted, respectively. The findings were robust to variation in parameter values over wide ranges in sensitivity analyses

  3. Plastic packaged microcircuits: Quality, reliability, and cost issues

    Science.gov (United States)

    Pecht, Michael G.; Agarwal, Rakesh; Quearry, Dan

    1993-12-01

    Plastic encapsulated microcircuits (PEMs) find their main application in commercial and telecommunication electronics. The advantages of PEMs in cost, size, weight, performance, and market lead-time, have attracted 97% of the market share of worldwide microcircuit sales. However, PEMs have always been resisted in US Government and military applications due to the perception that PEM reliability is low. This paper surveys plastic packaging with respect to the issues of reliability, market lead-time, performance, cost, and weight as a means to guide part-selection and system-design.

  4. Costs and expected gain in lifetime health from intensive care versus general ward care of 30,712 individual patients: a distribution-weighted cost-effectiveness analysis.

    Science.gov (United States)

    Lindemark, Frode; Haaland, Øystein A; Kvåle, Reidar; Flaatten, Hans; Norheim, Ole F; Johansson, Kjell A

    2017-08-21

    Clinicians, hospital managers, policy makers, and researchers are concerned about high costs, increased demand, and variation in priorities in the intensive care unit (ICU). The objectives of this modelling study are to describe the extra costs and expected health gains associated with admission to the ICU versus the general ward for 30,712 patients and the variation in cost-effectiveness estimates among subgroups and individuals, and to perform a distribution-weighted economic evaluation incorporating extra weighting to patients with high severity of disease. We used a decision-analytic model that estimates the incremental cost per quality-adjusted life year (QALY) gained (ICER) from ICU admission compared with general ward care using Norwegian registry data from 2008 to 2010. We assigned increasing weights to health gains for those with higher severity of disease, defined as less expected lifetime health if not admitted. The study has inherent uncertainty of findings because a randomized clinical trial comparing patients admitted or rejected to the ICU has never been performed. Uncertainty is explored in probabilistic sensitivity analysis. The mean cost-effectiveness of ICU admission versus ward care was €11,600/QALY, with 1.6 QALYs gained and an incremental cost of €18,700 per patient. The probability (p) of cost-effectiveness was 95% at a threshold of €22,000/QALY. The mean ICER for medical admissions was €10,700/QALY (p = 97%), €12,300/QALY (p = 93%) for admissions after acute surgery, and €14,700/QALY (p = 84%) after planned surgery. For individualized ICERs, there was a 50% probability that ICU admission was cost-effective for 85% of the patients at a threshold of €64,000/QALY, leaving 15% of the admissions not cost-effective. In the distributional evaluation, 8% of all patients had distribution-weighted ICERs (higher weights to gains for more severe conditions) above €64,000/QALY. High-severity admissions gained the most, and were more

  5. Transition costs in the electricity industry: A summary of issues

    Energy Technology Data Exchange (ETDEWEB)

    Baxter, L.; Hirst, E.; Hadley, S.

    1996-10-01

    Progress is evident as the restructuring debate in the U.S. electricity industry completes its third year. The Federal Energy Regulatory Commission released a final rule on transmission open access-a key element to facilitate more efficient wholesale markets. The majority of states have initiated investigations or discussions on restructuring retail markets. Yet hurdles remain in formulating and implementing state-level restructuring proposals. Perhaps foremost among these hurdles is the issue of transition costs (the potential monetary losses experienced by utilities, consumers, and other economic actors as a result of government initiatives to transform electricity generation from a regulated to a competitive market). Transition costs are approximately equal to the difference between the embedded cost for generation services under traditional cost-of-service regulation and the competitive-market price for power. When government takes action to open current monopoly franchises to multiple generation providers and the competitive-market price falls below embedded generation costs, then transition costs will arise. Transition costs will include one or more of the following four classes of costs: (1) assets, primarily utility-owned power plants; (2) liabilities, primarily long-term power-purchase and fuel-supply contracts; (3) regulatory assets, including deferred expenses and costs that regulators allow utilities to place on their balance sheets; and (4) public-policy programs, such as energy efficiency, low-income programs, and research and development. What is at issue in the transition-cost debate? The debate turns on four questions: (1) How large are the potential transition costs from restructuring? (2) How are these costs estimated? (3) What, if anything, might be done to address these costs? (4) Who will ultimately pay for any remaining costs and how? This paper summarizes some of the key results from a project at ORNL that addresses these four questions.

  6. Uncertainty in techno-economic estimates of cellulosic ethanol production due to experimental measurement uncertainty

    Directory of Open Access Journals (Sweden)

    Vicari Kristin J

    2012-04-01

    Full Text Available Abstract Background Cost-effective production of lignocellulosic biofuels remains a major financial and technical challenge at the industrial scale. A critical tool in biofuels process development is the techno-economic (TE model, which calculates biofuel production costs using a process model and an economic model. The process model solves mass and energy balances for each unit, and the economic model estimates capital and operating costs from the process model based on economic assumptions. The process model inputs include experimental data on the feedstock composition and intermediate product yields for each unit. These experimental yield data are calculated from primary measurements. Uncertainty in these primary measurements is propagated to the calculated yields, to the process model, and ultimately to the economic model. Thus, outputs of the TE model have a minimum uncertainty associated with the uncertainty in the primary measurements. Results We calculate the uncertainty in the Minimum Ethanol Selling Price (MESP estimate for lignocellulosic ethanol production via a biochemical conversion process: dilute sulfuric acid pretreatment of corn stover followed by enzymatic hydrolysis and co-fermentation of the resulting sugars to ethanol. We perform a sensitivity analysis on the TE model and identify the feedstock composition and conversion yields from three unit operations (xylose from pretreatment, glucose from enzymatic hydrolysis, and ethanol from fermentation as the most important variables. The uncertainty in the pretreatment xylose yield arises from multiple measurements, whereas the glucose and ethanol yields from enzymatic hydrolysis and fermentation, respectively, are dominated by a single measurement: the fraction of insoluble solids (fIS in the biomass slurries. Conclusions We calculate a $0.15/gal uncertainty in MESP from the TE model due to uncertainties in primary measurements. This result sets a lower bound on the error bars of

  7. Aid Effectiveness, Transaction Costs and Conditionality in the Education Sector

    Science.gov (United States)

    Ashford, Richard; Biswas, Shampa

    2010-01-01

    The reduction of transaction costs is a commonly mentioned yet rarely elaborated goal for aid effectiveness in educational development. The casual use of the concept of transaction costs conceals which costs may be reduced, which costs are required and, indeed, what transaction costs actually are. Examining issues related to harmonizing the…

  8. Key Issues and Challenges in Estimating the Cost of Capital for Energy Network Utilities in Emerging Markets(Gelişmekte Olan Ülkelerde Enerji Şebeke Şirketleri İçin Sermaye Maliyetinin Tahminindeki Ana Konu ve Sorunlar

    Directory of Open Access Journals (Sweden)

    Mustafa GÖZEN

    2012-01-01

    Full Text Available Estimating the cost of capital in emerging markets presents greater difficulties because these markets have relatively illiquid capital markets and higher levels of sovereign risk, economic uncertainties, and political risks. Experience shows that in estimating cost of capital, energy regulators in emerging countries usually depend on the work and recommendations of their staff and/or outside consultancy services. Since the ultimate decision is made by regulators, they need to understand the challenges and key issues in estimating a fair and reasonable cost of capital for energy utilities. The article introduces and discusses the key issues and challenges that regulators have to deal with when estimating cost of capital. Unfortunately, there is no agreement among academics, regulators, bankers, and other practitioners on how to address the key issues and challenges in determining the cost of capital in emerging economies. This makes capital cost estimation even more difficult in emerging economies.

  9. Building uncertainty into cost-effectiveness rankings: portfolio risk-return tradeoffs and implications for decision rules.

    Science.gov (United States)

    O'Brien, B J; Sculpher, M J

    2000-05-01

    Current principles of cost-effectiveness analysis emphasize the rank ordering of programs by expected economic return (eg, quality-adjusted life-years gained per dollar expended). This criterion ignores the variance associated with the cost-effectiveness of a program, yet variance is a common measure of risk when financial investment options are appraised. Variation in health care program return is likely to be a criterion of program selection for health care managers with fixed budgets and outcome performance targets. Characterizing health care resource allocation as a risky investment problem, we show how concepts of portfolio analysis from financial economics can be adopted as a conceptual framework for presenting cost-effectiveness data from multiple programs as mean-variance data. Two specific propositions emerge: (1) the current convention of ranking programs by expected return is a special case of the portfolio selection problem in which the decision maker is assumed to be indifferent to risk, and (2) for risk-averse decision makers, the degree of joint risk or covariation in cost-effectiveness between programs will create incentives to diversify an investment portfolio. The conventional normative assumption of risk neutrality for social-level public investment decisions does not apply to a large number of health care resource allocation decisions in which health care managers seek to maximize returns subject to budget constraints and performance targets. Portfolio theory offers a useful framework for studying mean-variance tradeoffs in cost-effectiveness and offers some positive predictions (and explanations) of actual decision making in the health care sector.

  10. Are financial incentives cost-effective to support smoking cessation during pregnancy?

    Science.gov (United States)

    Boyd, Kathleen A; Briggs, Andrew H; Bauld, Linda; Sinclair, Lesley; Tappin, David

    2016-02-01

    To investigate the cost-effectiveness of up to £400 worth of financial incentives for smoking cessation in pregnancy as an adjunct to routine health care. Cost-effectiveness analysis based on a Phase II randomized controlled trial (RCT) and a cost-utility analysis using a life-time Markov model. The RCT was undertaken in Glasgow, Scotland. The economic analysis was undertaken from the UK National Health Service (NHS) perspective. A total of 612 pregnant women randomized to receive usual cessation support plus or minus financial incentives of up to £400 vouchers (US $609), contingent upon smoking cessation. Comparison of usual support and incentive interventions in terms of cotinine-validated quitters, quality-adjusted life years (QALYs) and direct costs to the NHS. The incremental cost per quitter at 34-38 weeks pregnant was £1127 ($1716).This is similar to the standard look-up value derived from Stapleton & West's published ICER tables, £1390 per quitter, by looking up the Cessation in Pregnancy Incentives Trial (CIPT) incremental cost (£157) and incremental 6-month quit outcome (0.14). The life-time model resulted in an incremental cost of £17 [95% confidence interval (CI) = -£93, £107] and a gain of 0.04 QALYs (95% CI = -0.058, 0.145), giving an ICER of £482/QALY ($734/QALY). Probabilistic sensitivity analysis indicates uncertainty in these results, particularly regarding relapse after birth. The expected value of perfect information was £30 million (at a willingness to pay of £30 000/QALY), so given current uncertainty, additional research is potentially worthwhile. Financial incentives for smoking cessation in pregnancy are highly cost-effective, with an incremental cost per quality-adjusted life years of £482, which is well below recommended decision thresholds. © 2015 Society for the Study of Addiction.

  11. Managing structural uncertainty in health economic decision models: a discrepancy approach

    OpenAIRE

    Strong, M.; Oakley, J.; Chilcott, J.

    2012-01-01

    Healthcare resource allocation decisions are commonly informed by computer model predictions of population mean costs and health effects. It is common to quantify the uncertainty in the prediction due to uncertain model inputs, but methods for quantifying uncertainty due to inadequacies in model structure are less well developed. We introduce an example of a model that aims to predict the costs and health effects of a physical activity promoting intervention. Our goal is to develop a framewor...

  12. Use of probabilistic methods for analysis of cost and duration uncertainties in a decision analysis framework

    International Nuclear Information System (INIS)

    Boak, D.M.; Painton, L.

    1995-01-01

    Probabilistic forecasting techniques have been used in many risk assessment and performance assessment applications on radioactive waste disposal projects such as Yucca Mountain and the Waste Isolation Pilot Plant (WIPP). Probabilistic techniques such as Monte Carlo and Latin Hypercube sampling methods are routinely used to treat uncertainties in physical parameters important in simulating radionuclide transport in a coupled geohydrologic system and assessing the ability of that system to comply with regulatory release limits. However, the use of probabilistic techniques in the treatment of uncertainties in the cost and duration of programmatic alternatives on risk and performance assessment projects is less common. Where significant uncertainties exist and where programmatic decisions must be made despite existing uncertainties, probabilistic techniques may yield important insights into decision options, especially when used in a decision analysis framework and when properly balanced with deterministic analyses. For relatively simple evaluations, these types of probabilistic evaluations can be made using personal computer-based software

  13. Cost-Effectiveness of Old and New Technologies for Aneuploidy Screening.

    Science.gov (United States)

    Sinkey, Rachel G; Odibo, Anthony O

    2016-06-01

    Cost-effectiveness analyses allow assessment of whether marginal gains from new technology are worth increased costs. Several studies have examined cost-effectiveness of Down syndrome (DS) screening and found it to be cost-effective. Noninvasive prenatal screening also appears to be cost-effective among high-risk women with respect to DS screening, but not for the general population. Chromosomal microarray (CMA) is a genetic sequencing method superior to but more expensive than karyotype. In light of CMAs greater ability to detect genetic abnormalities, it is cost-effective when used for prenatal diagnosis of an anomalous fetus. This article covers methodology and salient issues of cost-effectiveness. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Regional disparity and cost-effective SO2 pollution control in China: A case study in 5 mega-cities

    International Nuclear Information System (INIS)

    Kanada, Momoe; Dong, Liang; Fujita, Tsuyoshi; Fujii, Minoru; Inoue, Tsuyoshi; Hirano, Yujiro; Togawa, Takuya; Geng, Yong

    2013-01-01

    With rapid development, increasing sulfur dioxide (SO 2 ) emission becomes a key environmental issue in China. To respond to this challenge, the Chinese government established a top-down scheme to reduce its SO 2 emissions. However, regional disparity and the associated cost differences brought uncertainties to the policy effectiveness and efficiency. Few studies focus on this field. Therefore, this study tries to fill such a gap by investigating the differences of SO 2 emissions, reduction potential, and cost-effectiveness through use of the GAINS-China model in five mega-cities in China, namely, Beijing, Shanghai, Tianjin, Chongqing, and Hong Kong. A scenario analysis approach is employed, focusing on two technologies named flue gas desulfurization (FGD) and limestone injection (LINJ). Results demonstrated that a large SO 2 reduction potential exists, as well as a great disparity, among the five mega-cities. Chongqing had the largest reduction potential with lowest unit cost, while Beijng and Hong Kong showed the lowest reduction potential with higher unit cost. In Beijing and Shanghai, FGD and LINJ in the power generation sector had the larger reduction potential with the highest cost-effectiveness. However, in Chongqing, the industry sectors also had large reduction potentials. Finally, appropriate SO 2 control strategies and policies are raised by considering the local realities. - Highlights: • The cost-effectiveness of SO 2 control policy was analyzed in five mega-cities in China. • Reduction potential and cost-effectiveness were closely linked to regional disparity. • Beijing and Hong Kong showed lower reduction potential and higher marginal reduction cost. • Chongqing showed the largest reduction potential and the lowest marginal reduction cost

  15. The business value and cost-effectiveness of genomic medicine.

    Science.gov (United States)

    Crawford, James M; Aspinall, Mara G

    2012-05-01

    Genomic medicine offers the promise of more effective diagnosis and treatment of human diseases. Genome sequencing early in the course of disease may enable more timely and informed intervention, with reduced healthcare costs and improved long-term outcomes. However, genomic medicine strains current models for demonstrating value, challenging efforts to achieve fair payment for services delivered, both for laboratory diagnostics and for use of molecular information in clinical management. Current models of healthcare reform stipulate that care must be delivered at equal or lower cost, with better patient and population outcomes. To achieve demonstrated value, genomic medicine must overcome many uncertainties: the clinical relevance of genomic variation; potential variation in technical performance and/or computational analysis; management of massive information sets; and must have available clinical interventions that can be informed by genomic analysis, so as to attain more favorable cost management of healthcare delivery and demonstrate improvements in cost-effectiveness.

  16. Measurement Uncertainty

    Science.gov (United States)

    Koch, Michael

    Measurement uncertainty is one of the key issues in quality assurance. It became increasingly important for analytical chemistry laboratories with the accreditation to ISO/IEC 17025. The uncertainty of a measurement is the most important criterion for the decision whether a measurement result is fit for purpose. It also delivers help for the decision whether a specification limit is exceeded or not. Estimation of measurement uncertainty often is not trivial. Several strategies have been developed for this purpose that will shortly be described in this chapter. In addition the different possibilities to take into account the uncertainty in compliance assessment are explained.

  17. U.S. NRC's generic issues program

    International Nuclear Information System (INIS)

    Kauffman, J.V.; Foster, J.W.

    2008-01-01

    The United States Nuclear Regulatory Commission (NRC) has a Generic Issues Program (GIP) to address Generic Issues (GI). A GI is defined as 'a regulatory matter involving the design, construction, operation, or decommissioning of several, or a class of, NRC licensees or certificate holders that is not sufficiently addressed by existing rules, guidance, or programs'. This rather legalistic definition has several practical corollaries: First, a GI must involve safety. Second, the issue must involve at least two plants, or it would be a plant-specific issue rather than a GI. Third, the potential safety question must not be covered by existing regulations and guidance (compliance). Thus, the effect of a GI is to potentially change the body of regulations and associated guidance (e.g., regulatory guides). The GIP was started in 1976, thus it is a relatively mature program. Approximately 850 issues have been processed by the program to date. More importantly, even after 30 years, new GIs continue to be proposed. The entire set of Generic Issues (GIs) is updated annually in NUREG-0933, 'A Prioritization of Generic Safety Issues'. GIs normally involve complex questions of safety and regulation. Efficient and effective means of addressing these issues are very important for regulatory effectiveness. If an issue proves to pose a genuine, significant safety question, then swift, effective, enforceable, and cost-effective action needs to be taken. Conversely, if an issue is of little safety significance, the issue should be dismissed in an expeditious manner, avoiding unnecessary expenditure of resources and regulatory burden or uncertainty. This paper provides a summary of the 5-stage program, from identification through the regulatory assessment stage. The paper also includes a discussion of the program's seven criteria, sources of proposed GIs, recent improvements, publicly available information, historical performance, and status of current GIs. (authors)

  18. Is implementation of the 2013 Australian treatment guidelines for posttraumatic stress disorder cost-effective compared to current practice? A cost-utility analysis using QALYs and DALYs.

    Science.gov (United States)

    Mihalopoulos, Cathrine; Magnus, Anne; Lal, Anita; Dell, Lisa; Forbes, David; Phelps, Andrea

    2015-04-01

    To assess, from a health sector perspective, the incremental cost-effectiveness of three treatment recommendations in the most recent Australian Clinical Practice Guidelines for posttraumatic stress disorder (PTSD). The interventions assessed are trauma-focused cognitive behavioural therapy (TF-CBT) and selective serotonin reuptake inhibitors (SSRIs) for the treatment of PTSD in adults and TF-CBT in children, compared to current practice in Australia. Economic modelling, using existing databases and published information, was used to assess cost-effectiveness. A cost-utility framework using both quality-adjusted life-years (QALYs) gained and disability-adjusted life-years (DALYs) averted was used. Costs were tracked for the duration of the respective interventions and applied to the estimated 12 months prevalent cases of PTSD in the Australian population of 2012. Simulation modelling was used to provide 95% uncertainty around the incremental cost-effectiveness ratios. Consideration was also given to factors not considered in the quantitative analysis but could determine the likely uptake of the proposed intervention guidelines. TF-CBT is highly cost-effective compared to current practice at $19,000/QALY, $16,000/DALY in adults and $8900/QALY, $8000/DALY in children. In adults, 100% of uncertainty iterations fell beneath the $50,000/QALY or DALY value-for-money threshold. Using SSRIs in people already on medications is cost-effective at $200/QALY, but has considerable uncertainty around the costs and benefits. While there is a 13% chance of health loss there is a 27% chance of the intervention dominating current practice by both saving dollars and improving health in adults. The three Guideline recommended interventions evaluated in this study are likely to have a positive impact on the economic efficiency of the treatment of PTSD if adopted in full. While there are gaps in the evidence base, policy-makers can have considerable confidence that the recommendations

  19. Innovative supply chain optimization models with multiple uncertainty factors

    DEFF Research Database (Denmark)

    Choi, Tsan Ming; Govindan, Kannan; Li, Xiang

    2017-01-01

    Uncertainty is an inherent factor that affects all dimensions of supply chain activities. In today’s business environment, initiatives to deal with one specific type of uncertainty might not be effective since other types of uncertainty factors and disruptions may be present. These factors relate...... to supply chain competition and coordination. Thus, to achieve a more efficient and effective supply chain requires the deployment of innovative optimization models and novel methods. This preface provides a concise review of critical research issues regarding innovative supply chain optimization models...

  20. Measuring the environmental benefits of hydrogen transportation fuel cycles under uncertainty about external costs

    International Nuclear Information System (INIS)

    Chernyavs'ka, Liliya; Gulli, Francesco

    2010-01-01

    In this paper, we attempt to measure the environmental benefits of hydrogen deployment in the transportation sector. We compare the hydrogen pathways to the conventional transportation fuel cycles in terms of external costs, estimated using the results of the most accurate methodologies available in this field. The central values of performed analysis bring us ambiguous results. The external cost of the best conventional solution ('oil to diesel hybrid internal-combustion engine') in some cases is just higher and in others just lower than that of the best fossil fuel to hydrogen solution ('natural gas to hydrogen fuel cell'). Nevertheless, by accounting for the uncertainty about external costs, we are able to remove this ambiguity highlighting that the hydrogen pathway provides significant environmental benefits ,especially in densely populated areas, assuming 100% city driving.

  1. Cost-effectiveness of pressure-relieving devices for the prevention and treatment of pressure ulcers.

    Science.gov (United States)

    Fleurence, Rachael L

    2005-01-01

    The cost-effectiveness of alternating pressure-relieving devices, mattress replacements, and mattress overlays compared with a standard hospital (high-specification foam mattress) for the prevention and treatment of pressure ulcers in hospital patients in the United Kingdom was investigated. A decision-analytic model was constructed to evaluate different strategies to prevent or treat pressure ulcers. Three scenarios were evaluated: the prevention of pressure ulcers, the treatment of superficial ulcers, and the treatment of severe ulcers. Epidemiological and effectiveness data were obtained from the clinical literature. Expert opinion using a rating scale technique was used to obtain quality of life data. Costs of the devices were obtained from manufacturers, whereas costs of treatment were obtained from the literature. Uncertainty was explored through probabilistic sensitivity analysis. Using 30,000 pounds sterling/QALY (quality-adjusted life year) as the decision-maker's cut off point (the current UK standard), in scenario 1 (prevention), the cost-effective strategy was the mattress overlay at 1, 4, and 12 weeks. In scenarios 2 and 3, the cost-effective strategy was the mattress replacement at 1, 4, and 12 weeks. Standard care was a dominated intervention in all scenarios for values of the decision-maker's ceiling ratio ranging from 5,000 pounds sterling to 100,000 pounds sterling/QALY. However, the probabilistic sensitivity analysis results reflected the high uncertainty surrounding the choice of devices. Current information suggests that alternating pressure mattress overlays may be cost-effective for the prevention of pressure ulcers, whereas alternating pressure mattress replacements appears to be cost-effective for the treatment of superficial and severe pressure ulcers.

  2. Cost-Effectiveness of a Nonpharmacological Intervention in Pediatric Burn Care.

    Science.gov (United States)

    Brown, Nadia J; David, Michael; Cuttle, Leila; Kimble, Roy M; Rodger, Sylvia; Higashi, Hideki

    2015-07-01

    To report the cost-effectiveness of a tailored handheld computerized procedural preparation and distraction intervention (Ditto) used during pediatric burn wound care in comparison to standard practice. An economic evaluation was performed alongside a randomized controlled trial of 75 children aged 4 to 13 years who presented with a burn to the Royal Children's Hospital, Brisbane, Australia. Participants were randomized to either the Ditto intervention (n = 35) or standard practice (n = 40) to measure the effect of the intervention on days taken for burns to re-epithelialize. Direct medical, direct nonmedical, and indirect cost data during burn re-epithelialization were extracted from the randomized controlled trial data and combined with scar management cost data obtained retrospectively from medical charts. Nonparametric bootstrapping was used to estimate statistical uncertainty in cost and effect differences and cost-effectiveness ratios. On average, the Ditto intervention reduced the time to re-epithelialize by 3 days at AU$194 less cost for each patient compared with standard practice. The incremental cost-effectiveness plane showed that 78% of the simulated results were within the more effective and less costly quadrant and 22% were in the more effective and more costly quadrant, suggesting a 78% probability that the Ditto intervention dominates standard practice (i.e., cost-saving). At a willingness-to-pay threshold of AU$120, there is a 95% probability that the Ditto intervention is cost-effective (or cost-saving) against standard care. This economic evaluation showed the Ditto intervention to be highly cost-effective against standard practice at a minimal cost for the significant benefits gained, supporting the implementation of the Ditto intervention during burn wound care. Copyright © 2015. Published by Elsevier Inc.

  3. Heavy ion fusion physics issues

    International Nuclear Information System (INIS)

    Bangerter, R.O.

    1984-01-01

    A simple systems model has been used to determine the sensitivity of the cost of electricity and the total cost of a power plant to the various uncertainties expressed in the following six issues. (1) can, at reasonable cost, an accelerator be built that puts more than 1 MJ of energy into a small 6-D phase space volume. (2) Can the beam be focused over a distance of several meters onto a small target in a reaction chamber. (3) Do present calculations adequately describe ion energy deposition. (4) Do current numerical simulations adequately describe the hydrodynamic and thermonuclear behavior of targets. (5) Can targets be cheaply mass produced. (6) Can an economical, tritium-breeding reactor be built

  4. Nuclear costs: indicators and uncertainties

    International Nuclear Information System (INIS)

    Leveque, Francois

    2013-01-01

    In order to identify whether it is better to build a gas plant, a nuclear plant or a wind farm, to identify the technology leading to the lowest KWh cost, to identify under which conditions nuclear production is profitable for a private investor, and to identify whether taking the dismantling cost and the waste storage cost into account modifies the nuclear competitiveness with respect to general interest, the author first discusses the different costs of the nuclear sector, their sensitivity to different factors. In a second part, he proposes a retrospective discussion of cost dynamics. Then, as nuclear technology seems characterized by always increasing costs, and as this trend may last, notably because of safety concerns, the author proposes an analysis of the poor competitiveness of nuclear with respect to its cost

  5. Cost-effectiveness of HIV prevention interventions in Andhra Pradesh state of India

    Directory of Open Access Journals (Sweden)

    Kumar G Anil

    2010-05-01

    Full Text Available Abstract Background Information on cost-effectiveness of the range of HIV prevention interventions is a useful contributor to decisions on the best use of resources to prevent HIV. We conducted this assessment for the state of Andhra Pradesh that has the highest HIV burden in India. Methods Based on data from a representative sample of 128 public-funded HIV prevention programs of 14 types in Andhra Pradesh, we have recently reported the number of HIV infections averted by each type of HIV prevention intervention and their cost. Using estimates of the age of onset of HIV infection, we used standard methods to calculate the cost per Disability Adjusted Life Year (DALY saved as a measure of cost-effectiveness of each type of HIV prevention intervention. Results The point estimates of the cost per DALY saved were less than US $50 for blood banks, men who have sex with men programmes, voluntary counselling and testing centres, prevention of parent to child transmission clinics, sexually transmitted infection clinics, and women sex worker programmes; between US $50 and 100 for truckers and migrant labourer programmes; more than US $100 and up to US $410 for composite, street children, condom promotion, prisoners and workplace programmes and mass media campaign for the general public. The uncertainty range around these estimates was very wide for several interventions, with the ratio of the high to the low estimates infinite for five interventions. Conclusions The point estimates for the cost per DALY saved from the averted HIV infections for all interventions was much lower than the per capita gross domestic product in this Indian state. While these indicative cost-effectiveness estimates can inform HIV control planning currently, the wide uncertainty range around estimates for several interventions suggest the need for more firm data for estimating cost-effectiveness of HIV prevention interventions in India.

  6. Aligning oversize/overweight fees with agency costs : critical issues.

    Science.gov (United States)

    2013-08-01

    This project provides an elementary analysis of issues and a proposed framework for the state to evaluate cost recovery options : due to OSOW operations. The authors provide a review of current permitting practices, provide a sampling of fee structur...

  7. How to perform a cost-effectiveness analysis with surrogate endpoint: renal denervation in patients with resistant hypertension (DENERHTN) trial as an example.

    Science.gov (United States)

    Bulsei, Julie; Darlington, Meryl; Durand-Zaleski, Isabelle; Azizi, Michel

    2018-04-01

    Whilst much uncertainty exists as to the efficacy of renal denervation (RDN), the positive results of the DENERHTN study in France confirmed the interest of an economic evaluation in order to assess efficiency of RDN and inform local decision makers about the costs and benefits of this intervention. The uncertainty surrounding both the outcomes and the costs can be described using health economic methods such as the non-parametric bootstrap. Internationally, numerous health economic studies using a cost-effectiveness model to assess the impact of RDN in terms of cost and effectiveness compared to antihypertensive medical treatment have been conducted. The DENERHTN cost-effectiveness study was the first health economic evaluation specifically designed to assess the cost-effectiveness of RDN using individual data. Using the DENERHTN results as an example, we provide here a summary of the principle methods used to perform a cost-effectiveness analysis.

  8. Exploratory Cost-Effectiveness Analysis of Response-Guided Neoadjuvant Chemotherapy for Hormone Positive Breast Cancer Patients.

    Directory of Open Access Journals (Sweden)

    Anna Miquel-Cases

    Full Text Available Guiding response to neoadjuvant chemotherapy (guided-NACT allows for an adaptative treatment approach likely to improve breast cancer survival. In this study, our primary aim is to explore the expected cost-effectiveness of guided-NACT using as a case study the first randomized controlled trial that demonstrated effectiveness (GeparTrio trial.As effectiveness was shown in hormone-receptor positive (HR+ early breast cancers (EBC, our decision model compared the health-economic outcomes of treating a cohort of such women with guided-NACT to conventional-NACT using clinical input data from the GeparTrio trial. The expected cost-effectiveness and the uncertainty around this estimate were estimated via probabilistic cost-effectiveness analysis (CEA, from a Dutch societal perspective over a 5-year time-horizon.Our exploratory CEA predicted that guided-NACT as proposed by the GeparTrio, costs additional €110, but results in 0.014 QALYs gained per patient. This scenario of guided-NACT was considered cost-effective at any willingness to pay per additional QALY. At the prevailing Dutch willingness to pay threshold (€80.000/QALY cost-effectiveness was expected with 78% certainty.This exploratory CEA indicated that guided-NACT (as proposed by the GeparTrio trial is likely cost-effective in treating HR+ EBC women. While prospective validation of the GeparTrio findings is advisable from a clinical perspective, early CEAs can be used to prioritize further research from a broader health economic perspective, by identifying which parameters contribute most to current decision uncertainty. Furthermore, their use can be extended to explore the expected cost-effectiveness of alternative guided-NACT scenarios that combine the use of promising imaging techniques together with personalized treatments.

  9. A Study on the Cost of Issuing Social Healthcare Corporation Bonds.

    Science.gov (United States)

    Fukunaga, Hajime; Yamauchi, Kazunobu

    2015-07-01

    The "Social Healthcare Corporation" system was established on 1 April 2007 as a result of the revised Japanese Medical Care Law. As of 1 October 2014, 234 corporations are certified Social Healthcare Corporations. These corporations are allowed to issue public bonds. However, to this day (1 December 2014), no bonds have been issued. In this paper, we focus on cost analysis with respect to issuing public bonds.

  10. Life cycle cost optimization of biofuel supply chains under uncertainties based on interval linear programming.

    Science.gov (United States)

    Ren, Jingzheng; Dong, Liang; Sun, Lu; Goodsite, Michael Evan; Tan, Shiyu; Dong, Lichun

    2015-01-01

    The aim of this work was to develop a model for optimizing the life cycle cost of biofuel supply chain under uncertainties. Multiple agriculture zones, multiple transportation modes for the transport of grain and biofuel, multiple biofuel plants, and multiple market centers were considered in this model, and the price of the resources, the yield of grain and the market demands were regarded as interval numbers instead of constants. An interval linear programming was developed, and a method for solving interval linear programming was presented. An illustrative case was studied by the proposed model, and the results showed that the proposed model is feasible for designing biofuel supply chain under uncertainties. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Notes on the effect of dose uncertainty

    International Nuclear Information System (INIS)

    Morris, M.D.

    1987-01-01

    The apparent dose-response relationship between amount of exposure to acute radiation and level of mortality in humans is affected by uncertainties in the dose values. It is apparent that one of the greatest concerns regarding the human data from Hiroshima and Nagasaki is the unexpectedly shallow slope of the dose response curve. This may be partially explained by uncertainty in the dose estimates. Some potential effects of dose uncertainty on the apparent dose-response relationship are demonstrated

  12. Cost-effectiveness analysis of treatments for premenstrual dysphoric disorder.

    Science.gov (United States)

    Rendas-Baum, Regina; Yang, Min; Gricar, Joseph; Wallenstein, Gene V

    2010-01-01

    Premenstrual syndrome (PMS) is reported to affect between 13% and 31% of women. Between 3% and 8% of women are reported to meet criteria for the more severe form of PMS, premenstrual dysphoric disorder (PMDD). Although PMDD has received increased attention in recent years, the cost effectiveness of treatments for PMDD remains unknown. To evaluate the cost effectiveness of the four medications with a US FDA-approved indication for PMDD: fluoxetine, sertraline, paroxetine and drospirenone plus ethinyl estradiol (DRSP/EE). A decision-analytic model was used to evaluate both direct costs (medication and physician visits) and clinical outcomes (treatment success, failure and discontinuation). Medication costs were based on average wholesale prices of branded products; physician visit costs were obtained from a claims database study of PMDD patients and the Agency for Healthcare Research and Quality. Clinical outcome probabilities were derived from published clinical trials in PMDD. The incremental cost-effectiveness ratio (ICER) was calculated using the difference in costs and percentage of successfully treated patients at 6 months. Deterministic and probabilistic sensitivity analyses were used to assess the impact of uncertainty in parameter estimates. Threshold values where a change in the cost-effective strategy occurred were identified using a net benefit framework. Starting therapy with DRSP/EE dominated both sertraline and paroxetine, but not fluoxetine. The estimated ICER of initiating treatment with fluoxetine relative to DRSP/EE was $US4385 per treatment success (year 2007 values). Cost-effectiveness acceptability curves revealed that for ceiling ratios>or=$US3450 per treatment success, fluoxetine had the highest probability (>or=0.37) of being the most cost-effective treatment, relative to the other options. The cost-effectiveness acceptability frontier further indicated that DRSP/EE remained the option with the highest expected net monetary benefit for

  13. Cost-effectiveness and evidence-based policy : Steering on social Impact

    NARCIS (Netherlands)

    van Yperen, Tom

    2016-01-01

    Introduction - The cost-effectiveness of many services is unknown. Because the demand for services is growing, whereas budgets are cut, the issue how to enhance the cost-effectiveness of Child and Youth Care is urgent in day to day politics and practice. The NJi developed a working model that helps

  14. Addressing model uncertainty in dose-response: The case of chloroform

    International Nuclear Information System (INIS)

    Evans, J.S.

    1994-01-01

    This paper discusses the issues involved in addressing model uncertainty in the analysis of dose-response relationships. A method for addressing model uncertainty is described and applied to characterize the uncertainty in estimates of the carcinogenic potency of chloroform. The approach, which is rooted in Bayesian concepts of subjective probability, uses probability trees and formally-elicited expert judgments to address model uncertainty. It is argued that a similar approach could be used to improve the characterization of model uncertainty in the dose-response relationships for health effects from ionizing radiation

  15. Optimal allocation of resources over health care programmes: dealing with decreasing marginal utility and uncertainty.

    Science.gov (United States)

    Al, Maiwenn J; Feenstra, Talitha L; Hout, Ben A van

    2005-07-01

    This paper addresses the problem of how to value health care programmes with different ratios of costs to effects, specifically when taking into account that these costs and effects are uncertain. First, the traditional framework of maximising health effects with a given health care budget is extended to a flexible budget using a value function over money and health effects. Second, uncertainty surrounding costs and effects is included in the model using expected utility. Other approaches to uncertainty that do not specify a utility function are discussed and it is argued that these also include implicit notions about risk attitude.

  16. Effectiveness of the food recovery at the retailing stage under shelf life uncertainty: An application to Italian food chains.

    Science.gov (United States)

    Muriana, Cinzia

    2015-07-01

    Food losses represent a significant issue affecting food supply chains. The possibility of recovering such products can be seen as an effective way to reduce such a phenomenon, improve supply chain performances and ameliorate the conditions of undernourished people. The topic has been already investigated by a previous paper enforcing the hypothesis of deterministic and constant Shelf Life (SL) of products. However, such a model cannot be properly extended to products affected by uncertainties of the SL as it does not take into account the deterioration costs and loss of profits due to the overcoming of the SL within the cycle time. Thus the present paper presents an extension of the previous one under stochastic conditions of the food quality. Differently from the previous publication, this work represents a general model applicable to all supply chains, especially to those managing fresh products characterized by uncertain SL such as fruits and vegetables. The deterioration costs and loss of profits are included in the model and the optimal time at which to withdraw the products from the shelves as well as the quantities to be shipped at each alternative destination have been determined. A comparison of the proposed model with that reported in the previous publication has been carried out in order to underline the impact of the SL variability on the optimality conditions. The results show that the food recovery strategy in the presence of uncertainty of the food quality is rewarding, even if the optimal profit is lower than that of the deterministic case. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Construction cost estimation of spherical storage tanks: artificial neural networks and hybrid regression—GA algorithms

    Science.gov (United States)

    Arabzadeh, Vida; Niaki, S. T. A.; Arabzadeh, Vahid

    2017-10-01

    One of the most important processes in the early stages of construction projects is to estimate the cost involved. This process involves a wide range of uncertainties, which make it a challenging task. Because of unknown issues, using the experience of the experts or looking for similar cases are the conventional methods to deal with cost estimation. The current study presents data-driven methods for cost estimation based on the application of artificial neural network (ANN) and regression models. The learning algorithms of the ANN are the Levenberg-Marquardt and the Bayesian regulated. Moreover, regression models are hybridized with a genetic algorithm to obtain better estimates of the coefficients. The methods are applied in a real case, where the input parameters of the models are assigned based on the key issues involved in a spherical tank construction. The results reveal that while a high correlation between the estimated cost and the real cost exists; both ANNs could perform better than the hybridized regression models. In addition, the ANN with the Levenberg-Marquardt learning algorithm (LMNN) obtains a better estimation than the ANN with the Bayesian-regulated learning algorithm (BRNN). The correlation between real data and estimated values is over 90%, while the mean square error is achieved around 0.4. The proposed LMNN model can be effective to reduce uncertainty and complexity in the early stages of the construction project.

  18. A Cost-effectiveness Analysis of Early vs Late Tracheostomy.

    Science.gov (United States)

    Liu, C Carrie; Rudmik, Luke

    2016-10-01

    The timing of tracheostomy in critically ill patients requiring mechanical ventilation is controversial. An important consideration that is currently missing in the literature is an evaluation of the economic impact of an early tracheostomy strategy vs a late tracheostomy strategy. To evaluate the cost-effectiveness of the early tracheostomy strategy vs the late tracheostomy strategy. This economic analysis was performed using a decision tree model with a 90-day time horizon. The economic perspective was that of the US health care third-party payer. The primary outcome was the incremental cost per tracheostomy avoided. Probabilities were obtained from meta-analyses of randomized clinical trials. Costs were obtained from the published literature and the Healthcare Cost and Utilization Project database. A multivariate probabilistic sensitivity analysis was performed to account for uncertainty surrounding mean values used in the reference case. The reference case demonstrated that the cost of the late tracheostomy strategy was $45 943.81 for 0.36 of effectiveness. The cost of the early tracheostomy strategy was $31 979.12 for 0.19 of effectiveness. The incremental cost-effectiveness ratio for the late tracheostomy strategy compared with the early tracheostomy strategy was $82 145.24 per tracheostomy avoided. With a willingness-to-pay threshold of $50 000, the early tracheostomy strategy is cost-effective with 56% certainty. The adaptation of an early vs a late tracheostomy strategy depends on the priorities of the decision-maker. Up to a willingness-to-pay threshold of $80 000 per tracheostomy avoided, the early tracheostomy strategy has a higher probability of being the more cost-effective intervention.

  19. Cost-effectiveness of pharmacotherapy to reduce obesity.

    Directory of Open Access Journals (Sweden)

    J Lennert Veerman

    Full Text Available AIMS: Obesity causes a high disease burden in Australia and across the world. We aimed to analyse the cost-effectiveness of weight reduction with pharmacotherapy in Australia, and to assess its potential to reduce the disease burden due to excess body weight. METHODS: We constructed a multi-state life-table based Markov model in Excel in which body weight influences the incidence of stroke, ischemic heart disease, hypertensive heart disease, diabetes mellitus, osteoarthritis, post-menopausal breast cancer, colon cancer, endometrial cancer and kidney cancer. We use data on effectiveness identified from PubMed searches, on mortality from Australian Bureau of Statistics, on disease costs from the Australian Institute of Health and Welfare, and on drug costs from the Department of Health and Ageing. We evaluate 1-year pharmacological interventions with sibutramine and orlistat targeting obese Australian adults free of obesity-related disease. We use a lifetime horizon for costs and health outcomes and a health sector perspective for costs. Incremental Cost-Effectiveness Ratios (ICERs below A$50 000 per Disability Adjusted Life Year (DALY averted are considered good value for money. RESULTS: The ICERs are A$130 000/DALY (95% uncertainty interval [UI] 93 000-180 000 for sibutramine and A$230 000/DALY (170 000-340 000 for orlistat. The interventions reduce the body weight-related disease burden at the population level by 0.2% and 0.1%, respectively. Modest weight loss during the interventions, rapid post-intervention weight regain and low adherence limit the health benefits. CONCLUSIONS: Treatment with sibutramine or orlistat is not cost-effective from an Australian health sector perspective and has a negligible impact on the total body weight-related disease burden.

  20. Force Structure: Capabilities and Cost of Army Modular Force Remain Uncertain

    National Research Council Canada - National Science Library

    2006-01-01

    .... In short, because of uncertainties in cost, equipment, and personnel plans and the absence of a comprehensive approach for assessing modularity results, we do not believe decision makers have sufficient information to assess the capabilities, costs, and risks posed by the transformation to a modular force. I will now turn to our four main issues.

  1. CO2 control technology effects on IGCC plant performance and cost

    International Nuclear Information System (INIS)

    Chen Chao; Rubin, Edward S.

    2009-01-01

    As part of the USDOE's Carbon Sequestration Program, an integrated modeling framework has been developed to evaluate the performance and cost of alternative carbon capture and storage (CCS) technologies for fossil-fueled power plants in the context of multi-pollutant control requirements. This paper uses the newly developed model of an integrated gasification combined cycle (IGCC) plant to analyze the effects of adding CCS to an IGCC system employing a GE quench gasifier with water gas shift reactors and a Selexol system for CO 2 capture. Parameters of interest include the effects on plant performance and cost of varying the CO 2 removal efficiency, the quality and cost of coal, and selected other factors affecting overall plant performance and cost. The stochastic simulation capability of the model is also used to illustrate the effect of uncertainties or variability in key process and cost parameters. The potential for advanced oxygen production and gas turbine technologies to reduce the cost and environmental impacts of IGCC with CCS is also analyzed

  2. Cost-effectiveness of per oral endoscopic myotomy relative to laparoscopic Heller myotomy for the treatment of achalasia.

    Science.gov (United States)

    Greenleaf, Erin K; Winder, Joshua S; Hollenbeak, Christopher S; Haluck, Randy S; Mathew, Abraham; Pauli, Eric M

    2018-01-01

    Per oral endoscopic myotomy (POEM) has recently emerged as a viable option relative to the classic approach of laparoscopic Heller myotomy (LHM) for the treatment of esophageal achalasia. In this cost-utility analysis of POEM and LHM, we hypothesized that POEM would be cost-effective relative to LHM. A stochastic cost-utility analysis of treatment for achalasia was performed to determine the cost-effectiveness of POEM relative to LHM. Costs were estimated from the provider perspective and obtained from our institution's cost-accounting database. The measure of effectiveness was quality-adjusted life years (QALYs) which were estimated from direct elicitation of utility using a visual analog scale. The primary outcome was the incremental cost-effectiveness ratio (ICER). Uncertainty was assessed by bootstrapping the sample and computing the cost-effectiveness acceptability curve (CEAC). Patients treated within an 11-year period (2004-2016) were recruited for participation (20 POEM, 21 LHM). During the index admission, the mean costs for POEM ($8630 ± $2653) and the mean costs for LHM ($7604 ± $2091) were not significantly different (P = 0.179). Additionally, mean QALYs for POEM (0.413 ± 0.248) were higher than that associated with LHM (0.357 ± 0.338), but this difference was also not statistically significant (P = 0.55). The ICER suggested that it would cost an additional $18,536 for each QALY gained using POEM. There was substantial uncertainty in the ICER; there was a 48.25% probability that POEM was cost-effective at the mean ICER. At a willingness-to-pay threshold of $100,000, there was a 68.31% probability that POEM was cost-effective relative to LHM. In the treatment of achalasia, POEM appears to be cost-effective relative to LHM depending on one's willingness-to-pay for an additional QALY.

  3. Issues related to uncertainty in projections of hazardous and mixed waste volumes in the U.S. Department of Energy's environmental restoration program

    International Nuclear Information System (INIS)

    Picel, K.C.

    1995-01-01

    Projected volumes of contaminated media and debris at US Department of Energy (DOE) environmental restoration sites that are potentially subject to the hazardous waste provisions of the Resource Conservation and Recovery Act are needed to support programmatic planning. Such projections have been gathered in various surveys conducted under DOE's environmental restoration and waste management programs. It is expected that reducing uncertainty in the projections through review of existing site data and process knowledge and through further site characterization will result in substantially lowered projections. If promulgated, the US Environmental Protection Agency's Hazardous Waste Identification Rule would result in potentially even greater reductions in the projections when site conditions are reviewed under the provisions of the new rule. Reducing uncertainty in projections under current and future waste identification rules may be necessary to support effective remediation planning. Further characterization efforts that may be conducted should be designed to limit uncertainty in identifying volumes of wastes to the extent needed to support alternative selection and to minimize costs of remediation

  4. Cost-effectiveness analysis of thermotherapy versus pentavalent antimonials for the treatment of cutaneous leishmaniasis.

    Science.gov (United States)

    Cardona-Arias, Jaiberth Antonio; López-Carvajal, Liliana; Tamayo Plata, Mery Patricia; Vélez, Iván Darío

    2017-05-01

    The treatment of cutaneous leishmaniasis is toxic, has contraindications, and a high cost. The objective of this study was to estimate the cost-effectiveness of thermotherapy versus pentavalent antimonials for the treatment of cutaneous leishmaniasis. Effectiveness was the proportion of healing and safety with the adverse effects; these parameters were estimated from a controlled clinical trial and a meta-analysis. A standard costing was conducted. Average and incremental cost-effectiveness ratios were estimated. The uncertainty regarding effectiveness, safety, and costs was determined through sensitivity analyses. The total costs were $66,807 with Glucantime and $14,079 with thermotherapy. The therapeutic effectiveness rates were 64.2% for thermotherapy and 85.1% for Glucantime. The average cost-effectiveness ratios ranged between $721 and $1275 for Glucantime and between $187 and $390 for thermotherapy. Based on the meta-analysis, thermotherapy may be a dominant strategy. The excellent cost-effectiveness ratio of thermotherapy shows the relevance of its inclusion in guidelines for the treatment. © 2017 Chinese Cochrane Center, West China Hospital of Sichuan University and John Wiley & Sons Australia, Ltd.

  5. Perseveration induces dissociative uncertainty in obsessive-compulsive disorder.

    Science.gov (United States)

    Giele, Catharina L; van den Hout, Marcel A; Engelhard, Iris M; Dek, Eliane C P; Toffolo, Marieke B J; Cath, Danielle C

    2016-09-01

    Obsessive compulsive (OC)-like perseveration paradoxically increases feelings of uncertainty. We studied whether the underlying mechanism between perseveration and uncertainty is a reduced accessibility of meaning ('semantic satiation'). OCD patients (n = 24) and matched non-clinical controls (n = 24) repeated words 2 (non-perseveration) or 20 times (perseveration). They decided whether this word was related to another target word. Speed of relatedness judgments and feelings of dissociative uncertainty were measured. The effects of real-life perseveration on dissociative uncertainty were tested in a smaller subsample of the OCD group (n = 9). Speed of relatedness judgments was not affected by perseveration. However, both groups reported more dissociative uncertainty after perseveration compared to non-perseveration, which was higher in OCD patients. Patients reported more dissociative uncertainty after 'clinical' perseveration compared to non-perseveration.. Both parts of this study are limited by some methodological issues and a small sample size. Although the mechanism behind 'perseveration → uncertainty' is still unclear, results suggest that the effects of perseveration are counterproductive. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Sensitivity of nuclear fuel cycle cost to uncertainties in nuclear data

    International Nuclear Information System (INIS)

    Harris, D.R.; Becker, M.; Parvez, A.; Ryskamp, J.M.

    1979-01-01

    A sensitivity analysis system is developed for assessing the economic implications of uncertainties in nuclear data and related computational methods for light water power reactors. Results of the sensitivity analysis indicate directions for worthwhile improvements in data and methods. Benefits from improvements in data and methods are related to reduction of margins provided by designers to ensure meeting reactor and fuel objectives. Sensitivity analyses are carried out using the batch depletion code FASTCELL, the core analysis code FASTCORE, and the reactor cost code COSTR. FASTCELL depletes a cell using methods comparable to industry cell codes except for a few-group treatment of cell flux distribution. FASTCORE is used with the Haling strategy of fixed power sharing among batches in the core. COSTR computes costs using components and techniques as in industry costing codes, except that COSTR uses fixed payment schedules. Sensitivity analyses are carried out for large commercial boiling and pressurized water reactors. Each few-group nuclear parameter is changed, and initial enrichment is also changed so as to keep the end-of-cycle core multiplication factor unchanged, i.e., to preserve cycle time at the demand power. Sensitivities of equilibrium fuel cycle cost are determined with respect to approx. 300 few-group nuclear parameters, both for a normal fuel cycle and for a throwaway fuel cycle. Particularly large dollar implications are found for thermal and resonance range cross sections in fissile and fertile materials. Sensitivities constrained by adjustment of fission neutron yield so as to preserve agreement with zero exposure integral data also are computed

  7. Beyond cost-effectiveness: Using systems analysis for infectious disease preparedness.

    Science.gov (United States)

    Phelps, Charles; Madhavan, Guruprasad; Rappuoli, Rino; Colwell, Rita; Fineberg, Harvey

    2017-01-20

    Until the recent outbreaks, Ebola vaccines ranked low in decision makers' priority lists based on cost-effectiveness analysis and (or) corporate profitability. Despite a relatively small number of Ebola-related cases and deaths (compared to other causes), Ebola vaccines suddenly leapt to highest priority among international health agencies and vaccine developers. Clearly, earlier cost-effectiveness analyses badly missed some factors affecting real world decisions. Multi-criteria systems analysis can improve evaluation and prioritization of vaccine development and also of many other health policy and investment decisions. Neither cost-effectiveness nor cost-benefit analysis can capture important aspects of problems such as Ebola or the emerging threat of Zika, especially issues of inequality and disparity-issues that dominate the planning of many global health and economic organizations. Cost-benefit analysis requires assumptions about the specific value of life-an idea objectionable to many analysts and policy makers. Additionally, standard cost-effectiveness calculations cannot generally capture effects on people uninfected with Ebola for example, but nevertheless affected through such factors as contagion, herd immunity, and fear of dread disease, reduction of travel and commerce, and even the hope of disease eradication. Using SMART Vaccines, we demonstrate how systems analysis can visibly include important "other factors" and more usefully guide decision making and beneficially alter priority setting processes. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  8. Encouraging smokers to quit: the cost effectiveness of reimbursing the costs of smoking cessation treatment.

    Science.gov (United States)

    Kaper, Janneke; Wagena, Edwin J; van Schayck, Constant P; Severens, Johan L

    2006-01-01

    Smoking cessation should be encouraged in order to increase life expectancy and reduce smoking-related healthcare costs. Results of a randomised trial suggested that reimbursing the costs of smoking cessation treatment (SCT) may lead to an increased use of SCT and an increased number of quitters versus no reimbursement. To assess whether reimbursement for SCT is a cost-effective intervention (from the Dutch societal perspective), we calculated the incremental costs per quitter and extrapolated this outcome to incremental costs per QALY saved versus no reimbursement. In the reimbursement trial, 1266 Dutch smokers were randomly assigned to the intervention or control group using a randomised double consent design. Reimbursement for SCT was offered to the intervention group for a period of 6 months. No reimbursement was offered to the control group. Prolonged abstinence from smoking was determined 6 months after the end of the reimbursement period. The QALYs gained from quitting were calculated until 80 years of age using data from the US. Costs (year 2002 values) were determined from the societal perspective during the reimbursement period (May-November 2002). Benefits were discounted at 4% per annum. The uncertainty of the incremental cost-effectiveness ratios was estimated using non-parametric bootstrapping. Eighteen participants in the control group (2.8%) and 35 participants in the intervention group (5.5%) successfully quit smoking. The costs per participant were 291 euro and 322 euro, respectively. If society is willing to pay 1000 euro or 10,000 euro for an additional 12-month quitter, the probability that reimbursement for SCT would be cost effective was 50% or 95%, respectively. If society is willing to pay 18,000 euro for a QALY, the probability that reimbursement for SCT would be cost effective was 95%. However, the external validity of the extrapolation from quitters to QALYs is uncertain and several assumptions had to be made. Reimbursement for SCT may

  9. Cost-effectiveness of tiotropium versus salmeterol: the POET-COPD trial.

    Science.gov (United States)

    Hoogendoorn, Martine; Al, Maiwenn J; Beeh, Kai-Michael; Bowles, David; Graf von der Schulenburg, J Matthias; Lungershausen, Juliane; Monz, Brigitta U; Schmidt, Hendrik; Vogelmeier, Claus; Rutten-van Mölken, Maureen P M H

    2013-03-01

    The aim of this study was to perform a 1-yr trial-based cost-effectiveness analysis (CEA) of tiotropium versus salmeterol followed by a 5-yr model-based CEA. The within-trial CEA, including 7,250 patients with moderate to very severe chronic obstructive pulmonary disease (COPD), was performed alongside the 1-yr international randomised controlled Prevention of Exacerbations with Tiotropium (POET)-COPD trial comparing tiotropium with salmeterol regarding the effect on exacerbations. Main end-points of the trial-based analysis were costs, number of exacerbations and exacerbation days. The model-based analysis was conducted to extrapolate results to 5 yrs and to calculate quality-adjusted life years (QALYs). 1-yr costs per patient from the German statutory health insurance (SHI) perspective and the societal perspective were €126 (95% uncertainty interval (UI) €55-195) and €170 (95% UI €77-260) higher for tiotropium, respectively. The annual number of exacerbations was 0.064 (95% UI 0.010-0.118) lower for tiotropium, leading to a reduction in exacerbation-related costs of €87 (95% UI €19-157). The incremental cost-effectiveness ratio was €1,961 per exacerbation avoided from the SHI perspective and €2,647 from the societal perspective. In the model-based analyses, the 5-yr costs per QALY were €3,488 from the SHI perspective and €8,141 from the societal perspective. Tiotropium reduced exacerbations and exacerbation-related costs, but increased total costs. Tiotropium can be considered cost-effective as the resulting cost-effectiveness ratios were below commonly accepted willingness-to-pay thresholds.

  10. Effect of Streamflow Forecast Uncertainty on Real-Time Reservoir Operation

    Science.gov (United States)

    Zhao, T.; Cai, X.; Yang, D.

    2010-12-01

    Various hydrological forecast products have been applied to real-time reservoir operation, including deterministic streamflow forecast (DSF), DSF-based probabilistic streamflow forecast (DPSF), and ensemble streamflow forecast (ESF), which represent forecast uncertainty in the form of deterministic forecast error, deterministic forecast error-based uncertainty distribution, and ensemble forecast errors, respectively. Compared to previous studies that treat these forecast products as ad hoc inputs for reservoir operation models, this paper attempts to model the uncertainties involved in the various forecast products and explores their effect on real-time reservoir operation decisions. In hydrology, there are various indices reflecting the magnitude of streamflow forecast uncertainty; meanwhile, few models illustrate the forecast uncertainty evolution process. This research introduces Martingale Model of Forecast Evolution (MMFE) from supply chain management and justifies its assumptions for quantifying the evolution of uncertainty in streamflow forecast as time progresses. Based on MMFE, this research simulates the evolution of forecast uncertainty in DSF, DPSF, and ESF, and applies the reservoir operation models (dynamic programming, DP; stochastic dynamic programming, SDP; and standard operation policy, SOP) to assess the effect of different forms of forecast uncertainty on real-time reservoir operation. Through a hypothetical single-objective real-time reservoir operation model, the results illustrate that forecast uncertainty exerts significant effects. Reservoir operation efficiency, as measured by a utility function, decreases as the forecast uncertainty increases. Meanwhile, these effects also depend on the type of forecast product being used. In general, the utility of reservoir operation with ESF is nearly as high as the utility obtained with a perfect forecast; the utilities of DSF and DPSF are similar to each other but not as efficient as ESF. Moreover

  11. Responding to the Challenge of True Uncertainty

    DEFF Research Database (Denmark)

    Hallin, Carina Antonia; Andersen, Torben Juul

    We construe a conceptual framework for responding effectively to true uncertainty in the business environment. We drill down to the essential micro-foundational capabilities - sensing and seizing of dynamic capabilities - and link them to classical strategic issue management theory with suggestions...... on how to operationalize these essential capabilities. By definition true uncertainty represents environmental conditions that are hard to foresee, which can catch the unprepared by surprise while presenting opportunities to the conscious organization. We demonstrate that organizations relying...

  12. Cost-effectiveness of a central venous catheter care bundle.

    Directory of Open Access Journals (Sweden)

    Kate A Halton

    Full Text Available BACKGROUND: A bundled approach to central venous catheter care is currently being promoted as an effective way of preventing catheter-related bloodstream infection (CR-BSI. Consumables used in the bundled approach are relatively inexpensive which may lead to the conclusion that the bundle is cost-effective. However, this fails to consider the nontrivial costs of the monitoring and education activities required to implement the bundle, or that alternative strategies are available to prevent CR-BSI. We evaluated the cost-effectiveness of a bundle to prevent CR-BSI in Australian intensive care patients. METHODS AND FINDINGS: A Markov decision model was used to evaluate the cost-effectiveness of the bundle relative to remaining with current practice (a non-bundled approach to catheter care and uncoated catheters, or use of antimicrobial catheters. We assumed the bundle reduced relative risk of CR-BSI to 0.34. Given uncertainty about the cost of the bundle, threshold analyses were used to determine the maximum cost at which the bundle remained cost-effective relative to the other approaches to infection control. Sensitivity analyses explored how this threshold alters under different assumptions about the economic value placed on bed-days and health benefits gained by preventing infection. If clinicians are prepared to use antimicrobial catheters, the bundle is cost-effective if national 18-month implementation costs are below $1.1 million. If antimicrobial catheters are not an option the bundle must cost less than $4.3 million. If decision makers are only interested in obtaining cash-savings for the unit, and place no economic value on either the bed-days or the health benefits gained through preventing infection, these cost thresholds are reduced by two-thirds. CONCLUSIONS: A catheter care bundle has the potential to be cost-effective in the Australian intensive care setting. Rather than anticipating cash-savings from this intervention, decision

  13. Model uncertainty and probability

    International Nuclear Information System (INIS)

    Parry, G.W.

    1994-01-01

    This paper discusses the issue of model uncertainty. The use of probability as a measure of an analyst's uncertainty as well as a means of describing random processes has caused some confusion, even though the two uses are representing different types of uncertainty with respect to modeling a system. The importance of maintaining the distinction between the two types is illustrated with a simple example

  14. Cost-effectiveness analysis of tenofovir disoproxil fumarate for treatment of chronic hepatitis B in China.

    Science.gov (United States)

    Ke, Weixia; Zhang, Chi; Liu, Li; Gao, Yanhui; Yao, Zhenjiang; Ye, Xiaohua; Zhou, Shudong; Yang, Yi

    2016-11-01

    Tenofovir disoproxil fumarate (TDF) is newly available for treatment of chronic hepatitis B patients in China. To date, no study has been conducted to examine the cost-effectiveness of this treatment. The aim of this study was to estimate the cost-effectiveness of TDF versus four oral nucleos(t)ide analogs [lamivudine (LAM), adefovir (ADV), telbivudine (LdT), and entecavir (ETV)] and from a pharmacoeconomic perspective to assess current drug pricing for TDF. Based on Chinese healthcare perspectives, a Markov model was applied to simulate the lifetime (40-year time span) costs and quality-adjusted life-years (QALYs) for five different monotherapy strategies. Two kinds of rescue combination strategies (base-case: LAM + ADV then ETV + ADV; alternative: directly using ETV + ADV) were separately considered for treatment of patients refractory to monotherapy. Model parameters (including disease transition, cost, and utility) were obtained from previous Chinese population studies. Both branded and generic drugs were separately analyzed. Study model uncertainties were assessed by one-way and probabilistic sensitivity analyses. Two-way sensitivity analysis was used to explore uncertainties between efficacy and price of TDF. In the base-case analysis, the lowest lifetime cost and the best cost-effectiveness ratio were obtained by ETV, which was considered the reference treatment. LAM, ADV, and LdT treatments had significantly greater costs and lower efficacies. Compared to ETV, TDF was more effective but also more expensive. The incremental cost-effectiveness ratios of TDF versus ETV were much higher than the willing-to-pay threshold of $20,466 US dollars (USD) per QALY gained (3 × gross domestic product per capita of China, 2014). TDF would be the most cost-effective strategy if the annual cost did not exceed $2260 USD and $1600 USD for branded and generic drugs, respectively. For Chinese chronic hepatitis B patients, ETV is still the most cost-effective

  15. Assessing Cost-Effectiveness in Obesity (ACE-Obesity: an overview of the ACE approach, economic methods and cost results

    Directory of Open Access Journals (Sweden)

    Swinburn Boyd

    2009-11-01

    Full Text Available Abstract Background The aim of the ACE-Obesity study was to determine the economic credentials of interventions which aim to prevent unhealthy weight gain in children and adolescents. We have reported elsewhere on the modelled effectiveness of 13 obesity prevention interventions in children. In this paper, we report on the cost results and associated methods together with the innovative approach to priority setting that underpins the ACE-Obesity study. Methods The Assessing Cost Effectiveness (ACE approach combines technical rigour with 'due process' to facilitate evidence-based policy analysis. Technical rigour was achieved through use of standardised evaluation methods, a research team that assembles best available evidence and extensive uncertainty analysis. Cost estimates were based on pathway analysis, with resource usage estimated for the interventions and their 'current practice' comparator, as well as associated cost offsets. Due process was achieved through involvement of stakeholders, consensus decisions informed by briefing papers and 2nd stage filter analysis that captures broader factors that influence policy judgements in addition to cost-effectiveness results. The 2nd stage filters agreed by stakeholders were 'equity', 'strength of the evidence', 'feasibility of implementation', 'acceptability to stakeholders', 'sustainability' and 'potential for side-effects'. Results The intervention costs varied considerably, both in absolute terms (from cost saving [6 interventions] to in excess of AUD50m per annum and when expressed as a 'cost per child' estimate (from Conclusion The use of consistent methods enables valid comparison of potential intervention costs and cost-offsets for each of the interventions. ACE-Obesity informs policy-makers about cost-effectiveness, health impact, affordability and 2nd stage filters for important options for preventing unhealthy weight gain in children. In related articles cost-effectiveness results and

  16. Aligning oversize/overweight permit fees with agency costs : critical issues.

    Science.gov (United States)

    2013-08-01

    This project provides an elementary analysis of issues and a proposed framework for the state to evaluate cost recovery options : due to OSOW operations. The authors provide a review of current permitting practices, provide a sampling of fee structur...

  17. Uncertainties associated with inertial-fusion ignition

    International Nuclear Information System (INIS)

    McCall, G.H.

    1981-01-01

    An estimate is made of a worst case driving energy which is derived from analytic and computer calculations. It will be shown that the uncertainty can be reduced by a factor of 10 to 100 if certain physical effects are understood. That is not to say that the energy requirement can necessarily be reduced below that of the worst case, but it is possible to reduce the uncertainty associated with ignition energy. With laser costs in the $0.5 to 1 billion per MJ range, it can be seen that such an exercise is worthwhile

  18. Cost-effectiveness of different strategies to manage patients with sciatica.

    Science.gov (United States)

    Fitzsimmons, Deborah; Phillips, Ceri J; Bennett, Hayley; Jones, Mari; Williams, Nefyn; Lewis, Ruth; Sutton, Alex; Matar, Hosam E; Din, Nafees; Burton, Kim; Nafees, Sadia; Hendry, Maggie; Rickard, Ian; Wilkinson, Claire

    2014-07-01

    The aim of this paper is to estimate the relative cost-effectiveness of treatment regimens for managing patients with sciatica. A deterministic model structure was constructed based on information from the findings from a systematic review of clinical effectiveness and cost-effectiveness, published sources of unit costs, and expert opinion. The assumption was that patients presenting with sciatica would be managed through one of 3 pathways (primary care, stepped approach, immediate referral to surgery). Results were expressed as incremental cost per patient with symptoms successfully resolved. Analysis also included incremental cost per utility gained over a 12-month period. One-way sensitivity analyses were used to address uncertainty. The model demonstrated that none of the strategies resulted in 100% success. For initial treatments, the most successful regime in the first pathway was nonopioids, with a probability of success of 0.613. In the second pathway, the most successful strategy was nonopioids, followed by biological agents, followed by epidural/nerve block and disk surgery, with a probability of success of 0.996. Pathway 3 (immediate surgery) was not cost-effective. Sensitivity analyses identified that the use of the highest cost estimates results in a similar overall picture. While the estimates of cost per quality-adjusted life year are higher, the economic model demonstrated that stepped approaches based on initial treatment with nonopioids are likely to represent the most cost-effective regimens for the treatment of sciatica. However, development of alternative economic modelling approaches is required. Copyright © 2014 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

  19. Are labour-intensive efforts to prevent pressure ulcers cost-effective?

    Science.gov (United States)

    Mathiesen, Anne Sofie Mølbak; Nørgaard, Kamilla; Andersen, Marie Frederikke Bruun; Møller, Klaus Meyer; Ehlers, Lars Holger

    2013-10-01

    Pressure ulcers are a major problem in Danish healthcare with a prevalence of 13-43% among hospitalized patients. The associated costs to the Danish Health Care Sector are estimated to be €174.5 million annually. In 2010, The Danish Society for Patient Safety introduced the Pressure Ulcer Bundle (PUB) in order to reduce hospital-acquired pressure ulcers by a minimum of 50% in five hospitals. The PUB consists of evidence-based preventive initiatives implemented by ward staff using the Model for Improvement. To investigate the cost-effectiveness of labour-intensive efforts to reduce pressure ulcers in the Danish Health Care Sector, comparing the PUB with standard care. A decision analytic model was constructed to assess the costs and consequences of hospital-acquired pressure ulcers during an average hospital admission in Denmark. The model inputs were based on a systematic review of clinical efficacy data combined with local cost and effectiveness data from the Thy-Mors Hospital, Denmark. A probabilistic sensitivity analysis (PSA) was conducted to assess the uncertainty. Prevention of hospital-acquired pressure ulcers by implementing labour-intensive effects according to the PUB was cost-saving and resulted in an improved effect compared to standard care. The incremental cost of the PUB was -€38.62. The incremental effects were a reduction of 9.3% prevented pressure ulcers and 0.47% prevented deaths. The PSAs confirmed the incremental cost-effectiveness ratio (ICER)'s dominance for both prevented pressure ulcers and saved lives with the PUB. This study shows that labour-intensive efforts to reduce pressure ulcers on hospital wards can be cost-effective and lead to savings in total costs of hospital and social care. The data included in the study regarding costs and effects of the PUB in Denmark were based on preliminary findings from a pilot study at Thy-Mors Hospital and literature.

  20. Proton therapy of cancer: Potential clinical advantages and cost-effectiveness

    International Nuclear Information System (INIS)

    Lundkvist, Jonas; Ekman, Mattias; Rehn Ericsson, Suzanne; Glimelius, Bengt; Akademiska sjukhuset, Uppsala

    2005-01-01

    Proton therapy may offer potential clinical advantages compared with conventional radiation therapy for many cancer patients. Due to the large investment costs for building a proton therapy facility, however, the treatment cost with proton radiation is higher than with conventional radiation. It is therefore important to evaluate whether the medical benefits of proton therapy are large enough to motivate the higher costs. We assessed the cost-effectiveness of proton therapy in the treatment of four different cancers: left-sided breast cancer, prostate cancer, head and neck cancer, and childhood medulloblastoma. A Markov cohort simulation model was created for each cancer type and used to simulate the life of patients treated with radiation. Cost and quality adjusted life years (QALYs) were used as primary outcome measures. The results indicated that proton therapy was cost-effective if appropriate risk groups were chosen. The average cost per QALY gained for the four types of cancer assessed was about Euro 10,130. If the value of a QALY was set to Euro 55,000, the total yearly net benefit of treating 925 cancer patients with the four types of cancer was about Euro 20.8 million. Investment in a proton facility may thus be cost-effective. The results must be interpreted with caution, since there is a lack of data, and consequently large uncertainties in the assumptions used

  1. Effect of Epistemic Uncertainty Modeling Approach on Decision-Making: Example using Equipment Performance Indicator

    Energy Technology Data Exchange (ETDEWEB)

    Dana Kelly; Robert Youngblood

    2012-06-01

    Quantitative risk assessments are an integral part of risk-informed regulation of current and future nuclear plants in the U.S. The Bayesian approach to uncertainty, in which both stochastic and epistemic uncertainties are represented with precise probability distributions, is the standard approach to modeling uncertainties in such quantitative risk assessments. However, there are long-standing criticisms of the Bayesian approach to epistemic uncertainty from many perspectives, and a number of alternative approaches have been proposed. Among these alternatives, the most promising (and most rapidly developing) would appear to be the concept of imprecise probability. In this paper, we employ a performance indicator example to focus the discussion. We first give a short overview of the traditional Bayesian paradigm and review some its controversial aspects, for example, issues with so-called noninformative prior distributions. We then discuss how the imprecise probability approach treats these issues and compare it with two other approaches: sensitivity analysis and hierarchical Bayes modeling. We conclude with some practical implications for risk-informed decision making.

  2. How to deal with climate change uncertainty in the planning of engineering systems

    Science.gov (United States)

    Spackova, Olga; Dittes, Beatrice; Straub, Daniel

    2016-04-01

    The effect of extreme events such as floods on the infrastructure and built environment is associated with significant uncertainties: These include the uncertain effect of climate change, uncertainty on extreme event frequency estimation due to limited historic data and imperfect models, and, not least, uncertainty on future socio-economic developments, which determine the damage potential. One option for dealing with these uncertainties is the use of adaptable (flexible) infrastructure that can easily be adjusted in the future without excessive costs. The challenge is in quantifying the value of adaptability and in finding the optimal sequence of decision. Is it worth to build a (potentially more expensive) adaptable system that can be adjusted in the future depending on the future conditions? Or is it more cost-effective to make a conservative design without counting with the possible future changes to the system? What is the optimal timing of the decision to build/adjust the system? We develop a quantitative decision-support framework for evaluation of alternative infrastructure designs under uncertainties, which: • probabilistically models the uncertain future (trough a Bayesian approach) • includes the adaptability of the systems (the costs of future changes) • takes into account the fact that future decisions will be made under uncertainty as well (using pre-posterior decision analysis) • allows to identify the optimal capacity and optimal timing to build/adjust the infrastructure. Application of the decision framework will be demonstrated on an example of flood mitigation planning in Bavaria.

  3. Cost-Effectiveness of Ventricular Assist Device Destination Therapy for Advanced Heart Failure in Duchenne Muscular Dystrophy.

    Science.gov (United States)

    Magnetta, Defne A; Kang, JaHyun; Wearden, Peter D; Smith, Kenneth J; Feingold, Brian

    2018-05-17

    Destination ventricular assist device therapy (DT-VAD) is well accepted in select adults with medically refractory heart failure (HF) who are not transplant candidates; however, its use in younger patients with progressive diseases is unclear. We sought to evaluate the cost-effectiveness of DT-VAD in Duchenne muscular dystrophy (DMD) patients with advanced HF. We created a Markov-state transition model (5-year horizon) to compare survival, costs, and quality of life (QOL) between medical management and DT-VAD in DMD with advanced HF. Model input parameters were derived from the literature. We used sensitivity analyses to explore uncertainty around model assumptions. DT-VAD had higher costs ($435,602 vs. $125,696), survival (3.13 vs. 0.60 years), and quality-adjusted survival (1.99 vs. 0.26 years) than medical management. The incremental cost-effectiveness ratio (ICER) for DT-VAD was $179,086 per quality-adjusted life year (QALY). In sensitivity analyses that were widely varied to account for uncertainty in model assumptions, the DT-VAD strategy generally remained more costly and effective than medical management. Only when VAD implantation costs were <$113,142 did the DT-VAD strategy fall below the $100,000/QALY willingness-to-pay threshold commonly considered to be "cost-effective." In this exploratory analysis, DT-VAD for patients with DMD and advanced HF exceeded societal expectations for cost-effectiveness but had an ICER similar to the accepted practice of DT-VAD in adult HF patients. While more experience and research in this population is needed, our analysis suggests that DT-VAD for advanced HF in DMD should not be dismissed solely based on cost.

  4. Methodology evaluation of innovative projects under risk and uncertainty

    Directory of Open Access Journals (Sweden)

    2012-09-01

    Full Text Available This article deals with problems connected with the assessment of innovative projects in the context of risk and uncertainty, topical issues of evaluation of innovative projects at the present stage of development of the Russian economy. By the example of the solution of the "crossing the river" is considering the possibility of using hierarchical models to address it. In what follows, and compares the priorities of different groups of factors are given by calculating the overall costs and benefits. The paper provides a rationale for combined use of four aspects: the beneficial aspects of the decision (the benefits and opportunities and negative (costs and risks that may lead to the decision in question.

  5. A cost effective degradation-based maintenance strategy under imperfect repair

    International Nuclear Information System (INIS)

    Wu, Fan; Niknam, Seyed A.; Kobza, John E.

    2015-01-01

    An optimization model is developed to minimize the total cost of imperfect degradation-based maintenance by determining an optimal interval of condition monitoring and the degradation level after imperfect preventive repairs. The decision model is based on a novel cost model that considers functional relationship between the expected degradation reduction and the cost of preventive repairs. The decision model is applied to simulated vibration signals with a variety of specifications of cost values and degradation model parameters. This study has initiated a new area for the research of cost effective maintenance strategies. The results clearly indicate the significance of the proposed model and the decision variables under the objective of minimal cost. For instance, the results indicate direct relationship between the optimal length of monitoring interval and the monitoring cost. However, longer monitoring interval increases the risk of failure, and therefore, more degradation reduction is needed. By increasing the slope of cumulative degradation, the cost effective strategy advocates taking more frequent monitoring. The optimal degradation level after each preventive repair is not so sensitive to the change in the degradation slope due to the uncertainty associated with degradation patterns. - Highlights: • Discuss the relationship of degradation reduction and maintenance cost. • Determine the optimal interval of condition monitoring with minimal cost. • Identify the optimal degradation level after imperfect preventive repairs. • Discuss the effects of change in the slope of cumulative degradation.

  6. State estimation bias induced by optimization under uncertainty and error cost asymmetry is likely reflected in perception.

    Science.gov (United States)

    Shimansky, Y P

    2011-05-01

    It is well known from numerous studies that perception can be significantly affected by intended action in many everyday situations, indicating that perception and related decision-making is not a simple, one-way sequence, but a complex iterative cognitive process. However, the underlying functional mechanisms are yet unclear. Based on an optimality approach, a quantitative computational model of one such mechanism has been developed in this study. It is assumed in the model that significant uncertainty about task-related parameters of the environment results in parameter estimation errors and an optimal control system should minimize the cost of such errors in terms of the optimality criterion. It is demonstrated that, if the cost of a parameter estimation error is significantly asymmetrical with respect to error direction, the tendency to minimize error cost creates a systematic deviation of the optimal parameter estimate from its maximum likelihood value. Consequently, optimization of parameter estimate and optimization of control action cannot be performed separately from each other under parameter uncertainty combined with asymmetry of estimation error cost, thus making the certainty equivalence principle non-applicable under those conditions. A hypothesis that not only the action, but also perception itself is biased by the above deviation of parameter estimate is supported by ample experimental evidence. The results provide important insights into the cognitive mechanisms of interaction between sensory perception and planning an action under realistic conditions. Implications for understanding related functional mechanisms of optimal control in the CNS are discussed.

  7. Applying the net-benefit framework for analyzing and presenting cost-effectiveness analysis of a maternal and newborn health intervention.

    Directory of Open Access Journals (Sweden)

    Sennen Hounton

    Full Text Available BACKGROUND: Coverage of maternal and newborn health (MNH interventions is often influenced by important determinants and decision makers are often concerned with equity issues. The net-benefit framework developed and applied alongside clinical trials and in pharmacoeconomics offers the potential for exploring how cost-effectiveness of MNH interventions varies at the margin by important covariates as well as for handling uncertainties around the ICER estimate. AIM: We applied the net-benefit framework to analyze cost-effectiveness of the Skilled Care Initiative and assessed relative advantages over a standard computation of incremental cost effectiveness ratios. METHODS: Household and facility surveys were carried out from January to July 2006 in Ouargaye district (where the Skilled Care Initiative was implemented and Diapaga (comparison site district in Burkina Faso. Pregnancy-related and perinatal mortality were retrospectively assessed and data were collected on place of delivery, education, asset ownership, place, and distance to health facilities, costs borne by households for institutional delivery, and cost of standard provision of maternal care. Descriptive and regression analyses were performed. RESULTS: There was a 30% increase in institutional births in the intervention district compared to 10% increase in comparison district, and a significant reduction of perinatal mortality rates (OR 0.75, CI 0.70-0.80 in intervention district. The incremental cost for achieving one additional institutional delivery in Ouargaye district compared to Diapaga district was estimated to be 170 international dollars and varied significantly by covariates. However, the joint probability distribution (net-benefit framework of the effectiveness measure (institutional delivery, the cost data and covariates indicated distance to health facilities as the single most important determinant of the cost-effectiveness analysis with implications for policy making

  8. Renewable energy costs, potentials, barriers: Conceptual issues

    International Nuclear Information System (INIS)

    Verbruggen, Aviel; Fischedick, Manfred; Moomaw, William; Weir, Tony; Nadai, Alain; Nilsson, Lars J.; Nyboer, John; Sathaye, Jayant

    2010-01-01

    Renewable energy can become the major energy supply option in low-carbon energy economies. Disruptive transformations in all energy systems are necessary for tapping widely available renewable energy resources. Organizing the energy transition from non-sustainable to renewable energy is often described as the major challenge of the first half of the 21st century. Technological innovation, the economy (costs and prices) and policies have to be aligned to achieve full renewable energy potentials, and barriers impeding that growth need to be removed. These issues are also covered by IPCC's special report on renewable energy and climate change to be completed in 2010. This article focuses on the interrelations among the drivers. It clarifies definitions of costs and prices, and of barriers. After reviewing how the third and fourth assessment reports of IPCC cover mitigation potentials and commenting on definitions of renewable energy potentials in the literature, we propose a consistent set of potentials of renewable energy supplies.

  9. An interval-based possibilistic programming method for waste management with cost minimization and environmental-impact abatement under uncertainty.

    Science.gov (United States)

    Li, Y P; Huang, G H

    2010-09-15

    Considerable public concerns have been raised in the past decades since a large amount of pollutant emissions from municipal solid waste (MSW) disposal of processes pose risks on surrounding environment and human health. Moreover, in MSW management, various uncertainties exist in the related costs, impact factors and objectives, which can affect the optimization processes and the decision schemes generated. In this study, an interval-based possibilistic programming (IBPP) method is developed for planning the MSW management with minimized system cost and environmental impact under uncertainty. The developed method can deal with uncertainties expressed as interval values and fuzzy sets in the left- and right-hand sides of constraints and objective function. An interactive algorithm is provided for solving the IBPP problem, which does not lead to more complicated intermediate submodels and has a relatively low computational requirement. The developed model is applied to a case study of planning a MSW management system, where mixed integer linear programming (MILP) technique is introduced into the IBPP framework to facilitate dynamic analysis for decisions of timing, sizing and siting in terms of capacity expansion for waste-management facilities. Three cases based on different waste-management policies are examined. The results obtained indicate that inclusion of environmental impacts in the optimization model can change the traditional waste-allocation pattern merely based on the economic-oriented planning approach. The results obtained can help identify desired alternatives for managing MSW, which has advantages in providing compromised schemes under an integrated consideration of economic efficiency and environmental impact under uncertainty. Copyright 2010 Elsevier B.V. All rights reserved.

  10. Uncertainty in artificial intelligence

    CERN Document Server

    Kanal, LN

    1986-01-01

    How to deal with uncertainty is a subject of much controversy in Artificial Intelligence. This volume brings together a wide range of perspectives on uncertainty, many of the contributors being the principal proponents in the controversy.Some of the notable issues which emerge from these papers revolve around an interval-based calculus of uncertainty, the Dempster-Shafer Theory, and probability as the best numeric model for uncertainty. There remain strong dissenting opinions not only about probability but even about the utility of any numeric method in this context.

  11. Identifying the effects of parameter uncertainty on the reliability of riverbank stability modelling

    Science.gov (United States)

    Samadi, A.; Amiri-Tokaldany, E.; Darby, S. E.

    2009-05-01

    Bank retreat is a key process in fluvial dynamics affecting a wide range of physical, ecological and socioeconomic issues in the fluvial environment. To predict the undesirable effects of bank retreat and to inform effective measures to prevent it, a wide range of bank stability models have been presented in the literature. These models typically express bank stability by defining a factor of safety as the ratio of driving and resisting forces acting on the incipient failure block. These forces are affected by a range of controlling factors that include such aspects as the bank profile (bank height and angle), the geotechnical properties of the bank materials, as well as the hydrological status of the riverbanks. In this paper we evaluate the extent to which uncertainties in the parameterization of these controlling factors feed through to influence the reliability of the resulting bank stability estimate. This is achieved by employing a simple model of riverbank stability with respect to planar failure (which is the most common type of bank stability model) in a series of sensitivity tests and Monte Carlo analyses to identify, for each model parameter, the range of values that induce significant changes in the simulated factor of safety. These identified parameter value ranges are compared to empirically derived parameter uncertainties to determine whether they are likely to confound the reliability of the resulting bank stability calculations. Our results show that parameter uncertainties are typically high enough that the likelihood of generating unreliable predictions is typically very high (> ˜ 80% for predictions requiring a precision of < ± 15%). Because parameter uncertainties are derived primarily from the natural variability of the parameters, rather than measurement errors, much more careful attention should be paid to field sampling strategies, such that the parameter uncertainties and consequent prediction unreliabilities can be quantified more

  12. Comparative risk-benefit-cost effectiveness in nuclear and alternate power sources: methodology, perspective, limitations

    International Nuclear Information System (INIS)

    Vinck, W.; Van Reijen, G.; Maurer, H.; Volta, G.

    1980-01-01

    A critical survey is given of the use of quantitative risk assessment in defining acceptable limits of safety and of its use together with cost-benefit analyses for decision making. The paper indicates uncertainties and even unknowns in risk assessment in particular if the whole fuel cycle for energy production is considered. It is made clear that for decisions on acceptance of risk also the risk perception factor must be considered. A difficult issue here is the potential for low-probability/large consequence accidents. Examples are given, suggestions for improvement are made and perspectives are outlined

  13. Tactical supply chain planning for a forest biomass power plant under supply uncertainty

    International Nuclear Information System (INIS)

    Shabani, Nazanin; Sowlati, Taraneh; Ouhimmou, Mustapha; Rönnqvist, Mikael

    2014-01-01

    Uncertainty in biomass supply is a critical issue that needs to be considered in the production planning of bioenergy plants. Incorporating uncertainty in supply chain planning models provides improved and stable solutions. In this paper, we first reformulate a previously developed non-linear programming model for optimization of a forest biomass power plant supply chain into a linear programming model. The developed model is a multi-period tactical-level production planning problem and considers the supply and storage of forest biomass as well as the production of electricity. It has a one-year planning horizon with monthly time steps. Next, in order to incorporate uncertainty in monthly available biomass into the planning, we develop a two-stage stochastic programming model. Finally, to balance the risk and profit, we propose a bi-objective model. The results show that uncertainty in availability of biomass has an additional cost of $0.4 million for the power plant. Using the proposed stochastic optimization model could reduce this cost by half. - Highlights: • Developed a two-stage stochastic optimization model to consider supply uncertainty. • Maximized the profit of a forest biomass power plant value chain. • Minimized two risk measures, variability index and downside risk, to manage risks. • Stochastic optimization model provided feasible solution for all scenarios. • Results showed a trade-off between profit and risk management

  14. Humans, 'things' and space: costing hospital infection control interventions.

    Science.gov (United States)

    Page, K; Graves, N; Halton, K; Barnett, A G

    2013-07-01

    Previous attempts at costing infection control programmes have tended to focus on accounting costs rather than economic costs. For studies using economic costs, estimates tend to be quite crude and probably underestimate the true cost. One of the largest costs of any intervention is staff time, but this cost is difficult to quantify and has been largely ignored in previous attempts. To design and evaluate the costs of hospital-based infection control interventions or programmes. This article also discusses several issues to consider when costing interventions, and suggests strategies for overcoming these issues. Previous literature and techniques in both health economics and psychology are reviewed and synthesized. This article provides a set of generic, transferable costing guidelines. Key principles such as definition of study scope and focus on large costs, as well as pitfalls (e.g. overconfidence and uncertainty), are discussed. These new guidelines can be used by hospital staff and other researchers to cost their infection control programmes and interventions more accurately. Copyright © 2013 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  15. Prioritization of generic safety issues

    International Nuclear Information System (INIS)

    Emrit, R.; Minners, W.; VanderMolen, H.

    1983-12-01

    This report presents the priority rankings for generic safety issues related to nuclear power plants. The purpose of these rankings is to assist in the timely and efficient allocation of NRC resources for the resolution of those safety issues that have a significant potential for reducing risk. The report focuses on the prioritization of generic safety issues. Issues primarily concerned with the licensing process or environmental protection and not directly related to safety have been excluded from prioritization. The prioritized issues include: TMI Action Plan items under development; previously proposed issues covered by Task Action Plans, except issues designated at Unresolved Safety Issues (USIs) which had already been assigned high priority; and newly-proposed issues. Future supplements to this report will include the prioritization of additional issues. The safety priority rankings are HIGH, MEDIUM, LOW, and DROP and have been assigned on the basis of risk significance estimates, the ratio of risk to costs and other impacts estimated to result if resolutions of the safety issues were implemented, and the consideration of uncertainties and other quantitative or qualitative factors. To the extent practical, estimates are quantitative

  16. Review of economics and cost-effectiveness analyses of anticoagulant therapy for stroke prevention in atrial fibrillation in the US.

    Science.gov (United States)

    von Schéele, Birgitta; Fernandez, Maria; Hogue, Susan Lynn; Kwong, Winghan Jacqueline

    2013-05-01

    To summarize the available evidence on the issues in health economics related to oral anticoagulation for stroke prevention in atrial fibrillation (AF) in the US. A literature review was performed using PubMed, EMBASE, Cochrane Library, and International Pharmaceutical Abstracts, as well as the websites of professional organizations. The search was conducted according to a prespecified protocol, limiting articles to those published in English from 2001 to October 2012 and focused on the economics associated with AF and AF-related stroke in the US. Data from 27 studies were extracted and included in the review. Strokes in patients with AF are more debilitating and have higher recurrence rates and mortality compared with strokes unrelated to AF. However, data describing the long-term cost of AF-related stroke and stroke subtypes remain limited. The costs of major gastrointestinal (GI) bleeding and intracranial bleeding related to warfarin are significant, whereas the costs of the more frequent minor GI bleeding are relatively low. Overall, the cost-effectiveness of warfarin versus aspirin or no treatment in patients with at least 1 risk factor for stroke is well established. Economic evaluations based on results from randomized controlled clinical trials generally found that new anticoagulants were a cost-effective alternative to warfarin for stroke prevention in AF. However, these cost-effectiveness results are highly sensitive to how well optimal international normalized ratio control is maintained (within target of 2.0-3.0) for warfarin and the time horizon used for analysis. Time in therapeutic range for warfarin in routine clinical practice was lower than in clinical trials, as shown by previous studies. This review identified several areas of uncertainty regarding the economic benefit of anticoagulants. The generalizability of cost-effectiveness results of anticoagulant therapy in AF based on clinical trial data must be confirmed by comparative effectiveness

  17. Identification of long-term containment/stabilization technology performance issues

    International Nuclear Information System (INIS)

    Matthern, G.E.; Nickelson, D.F.

    1997-01-01

    U.S. Department of Energy (DOE) faces a somewhat unique challenge when addressing in situ remedial alternatives that leave long-lived radionuclides and hazardous contaminants onsite. These contaminants will remain a potential hazard for thousands of years. However, the risks, costs, and uncertainties associated with removal and offsite disposal are leading many sites to select in situ disposal alternatives. Improvements in containment, stabilization, and monitoring technologies will enhance the viability of such alternatives for implementation. DOE's Office of Science and Technology sponsored a two day workshop designed to investigate issues associated with the long-term in situ stabilization and containment of buried, long-lived hazardous and radioactive contaminants. The workshop facilitated communication among end users representing most sites within the DOE, regulators, and technologists to define long-term performance issues for in situ stabilization and containment alternatives. Participants were divided into groups to identify issues and a strategy to address priority issues. This paper presents the results of the working groups and summarizes the conclusions. A common issue identified by the work groups is communication. Effective communication between technologists, risk assessors, end users, regulators, and other stakeholders would contribute greatly to resolution of both technical and programmatic issues

  18. Probabilistic accident consequence uncertainty analysis -- Early health effects uncertainty assessment. Volume 2: Appendices

    Energy Technology Data Exchange (ETDEWEB)

    Haskin, F.E. [Univ. of New Mexico, Albuquerque, NM (United States); Harper, F.T. [Sandia National Labs., Albuquerque, NM (United States); Goossens, L.H.J.; Kraan, B.C.P. [Delft Univ. of Technology (Netherlands)

    1997-12-01

    The development of two new probabilistic accident consequence codes, MACCS and COSYMA, was completed in 1990. These codes estimate the consequence from the accidental releases of radiological material from hypothesized accidents at nuclear installations. In 1991, the US Nuclear Regulatory Commission and the Commission of the European Communities began cosponsoring a joint uncertainty analysis of the two codes. The ultimate objective of this joint effort was to systematically develop credible and traceable uncertainty distributions for the respective code input variables. A formal expert judgment elicitation and evaluation process was identified as the best technology available for developing a library of uncertainty distributions for these consequence parameters. This report focuses on the results of the study to develop distribution for variables related to the MACCS and COSYMA early health effects models. This volume contains appendices that include (1) a summary of the MACCS and COSYMA consequence codes, (2) the elicitation questionnaires and case structures, (3) the rationales and results for the panel on early health effects, (4) short biographies of the experts, and (5) the aggregated results of their responses.

  19. Educational interventions to improve quality of life in people with chronic inflammatory skin diseases: systematic reviews of clinical effectiveness and cost-effectiveness.

    Science.gov (United States)

    Pickett, Karen; Loveman, Emma; Kalita, Neelam; Frampton, Geoff K; Jones, Jeremy

    2015-10-01

    psoriasis. Carers of children in one RCT of eczema showed improvement in HRQoL; however, in a RCT evaluating a website intervention there were no demonstrable effects on HRQoL. Neither the RCT in those adults with acne nor the RCT in those adults with mixed skin conditions demonstrated an effect on HRQoL. One RCT reported subgroups with atopic dermatitis or psoriasis and education was effective for psoriasis only. Other outcomes also showed mixed results. It is unclear how clinically meaningful any of the observed improvements are. Three studies of cost-effectiveness were included. The interventions, comparators and populations varied across the studies and, overall, the studies provided limited information on cost-effectiveness. The studies did provide detailed information on resources and costs that could be useful to inform a future cost-effectiveness evaluation in this area. The application of the inclusion criterion around whether the interventions were aimed at improving HRQoL or the inference that they could improve HRQoL was difficult as information was rarely reported. There is uncertainty regarding whether educational interventions addressing issues that could improve HRQoL in people with chronic skin conditions are effective. Tentative conclusions about the best approach to delivering these kinds of interventions are that face-to-face, group, sessions may be beneficial; however, text messages may also be effective. Delivery over a period of time and by a multidisciplinary team may also be associated with positive outcomes. There is uncertainty over whether or not educational interventions are cost-effective. This study is registered as PROSPERO CRD42014007426. The National Institute for Health Research Health Technology Assessment programme.

  20. A comparative analysis of methods to represent uncertainty in estimating the cost of constructing wastewater treatment plants.

    Science.gov (United States)

    Chen, Ho-Wen; Chang, Ni-Bin

    2002-08-01

    Prediction of construction cost of wastewater treatment facilities could be influential for the economic feasibility of various levels of water pollution control programs. However, construction cost estimation is difficult to precisely evaluate in an uncertain environment and measured quantities are always burdened with different types of cost structures. Therefore, an understanding of the previous development of wastewater treatment plants and of the related construction cost structures of those facilities becomes essential for dealing with an effective regional water pollution control program. But deviations between the observed values and the estimated values are supposed to be due to measurement errors only in the conventional regression models. The inherent uncertainties of the underlying cost structure, where the human estimation is influential, are rarely explored. This paper is designed to recast a well-known problem of construction cost estimation for both domestic and industrial wastewater treatment plants via a comparative framework. Comparisons were made for three technologies of regression analyses, including the conventional least squares regression method, the fuzzy linear regression method, and the newly derived fuzzy goal regression method. The case study, incorporating a complete database with 48 domestic wastewater treatment plants and 29 industrial wastewater treatment plants being collected in Taiwan, implements such a cost estimation procedure in an uncertain environment. Given that the fuzzy structure in regression estimation may account for the inherent human complexity in cost estimation, the fuzzy goal regression method does exhibit more robust results in terms of some criteria. Moderate economy of scale exists in constructing both the domestic and industrial wastewater treatment plants. Findings indicate that the optimal size of a domestic wastewater treatment plant is approximately equivalent to 15,000 m3/day (CMD) and higher in Taiwan

  1. Routine Pediatric Enterovirus 71 Vaccination in China: a Cost-Effectiveness Analysis.

    Science.gov (United States)

    Wu, Joseph T; Jit, Mark; Zheng, Yaming; Leung, Kathy; Xing, Weijia; Yang, Juan; Liao, Qiaohong; Cowling, Benjamin J; Yang, Bingyi; Lau, Eric H Y; Takahashi, Saki; Farrar, Jeremy J; Grenfell, Bryan T; Leung, Gabriel M; Yu, Hongjie

    2016-03-01

    China accounted for 87% (9.8 million/11.3 million) of all hand, foot, and mouth disease (HFMD) cases reported to WHO during 2010-2014. Enterovirus 71 (EV71) is responsible for most of the severe HFMD cases. Three EV71 vaccines recently demonstrated good efficacy in children aged 6-71 mo. Here we assessed the cost-effectiveness of routine pediatric EV71 vaccination in China. We characterized the economic and health burden of EV71-associated HFMD (EV71-HFMD) in China using (i) the national surveillance database, (ii) virological surveillance records from all provinces, and (iii) a caregiver survey on the household costs and health utility loss for 1,787 laboratory-confirmed pediatric cases. Using a static model parameterized with these data, we estimated the effective vaccine cost (EVC, defined as cost/efficacy or simply the cost of a 100% efficacious vaccine) below which routine pediatric vaccination would be considered cost-effective. We performed the base-case analysis from the societal perspective with a willingness-to-pay threshold of one times the gross domestic product per capita (GDPpc) and an annual discount rate of 3%. We performed uncertainty analysis by (i) accounting for the uncertainty in the risk of EV71-HFMD due to missing laboratory data in the national database, (ii) excluding productivity loss of parents and caregivers, (iii) increasing the willingness-to-pay threshold to three times GDPpc, (iv) increasing the discount rate to 6%, and (v) accounting for the proportion of EV71-HFMD cases not registered by national surveillance. In each of these scenarios, we performed probabilistic sensitivity analysis to account for parametric uncertainty in our estimates of the risk of EV71-HFMD and the expected costs and health utility loss due to EV71-HFMD. Routine pediatric EV71 vaccination would be cost-saving if the all-inclusive EVC is below US$10.6 (95% CI US$9.7-US$11.5) and would remain cost-effective if EVC is below US$17.9 (95% CI US$16.9-US$18.8) in

  2. Routine Pediatric Enterovirus 71 Vaccination in China: a Cost-Effectiveness Analysis

    Science.gov (United States)

    Leung, Kathy; Xing, Weijia; Yang, Juan; Liao, Qiaohong; Cowling, Benjamin J.; Yang, Bingyi; Lau, Eric H. Y.; Takahashi, Saki; Farrar, Jeremy J.; Grenfell, Bryan T.; Leung, Gabriel M.; Yu, Hongjie

    2016-01-01

    Background China accounted for 87% (9.8 million/11.3 million) of all hand, foot, and mouth disease (HFMD) cases reported to WHO during 2010–2014. Enterovirus 71 (EV71) is responsible for most of the severe HFMD cases. Three EV71 vaccines recently demonstrated good efficacy in children aged 6–71 mo. Here we assessed the cost-effectiveness of routine pediatric EV71 vaccination in China. Methods and Findings We characterized the economic and health burden of EV71-associated HFMD (EV71-HFMD) in China using (i) the national surveillance database, (ii) virological surveillance records from all provinces, and (iii) a caregiver survey on the household costs and health utility loss for 1,787 laboratory-confirmed pediatric cases. Using a static model parameterized with these data, we estimated the effective vaccine cost (EVC, defined as cost/efficacy or simply the cost of a 100% efficacious vaccine) below which routine pediatric vaccination would be considered cost-effective. We performed the base-case analysis from the societal perspective with a willingness-to-pay threshold of one times the gross domestic product per capita (GDPpc) and an annual discount rate of 3%. We performed uncertainty analysis by (i) accounting for the uncertainty in the risk of EV71-HFMD due to missing laboratory data in the national database, (ii) excluding productivity loss of parents and caregivers, (iii) increasing the willingness-to-pay threshold to three times GDPpc, (iv) increasing the discount rate to 6%, and (v) accounting for the proportion of EV71-HFMD cases not registered by national surveillance. In each of these scenarios, we performed probabilistic sensitivity analysis to account for parametric uncertainty in our estimates of the risk of EV71-HFMD and the expected costs and health utility loss due to EV71-HFMD. Routine pediatric EV71 vaccination would be cost-saving if the all-inclusive EVC is below US$10.6 (95% CI US$9.7–US$11.5) and would remain cost-effective if EVC is below

  3. Routine Pediatric Enterovirus 71 Vaccination in China: a Cost-Effectiveness Analysis.

    Directory of Open Access Journals (Sweden)

    Joseph T Wu

    2016-03-01

    Full Text Available China accounted for 87% (9.8 million/11.3 million of all hand, foot, and mouth disease (HFMD cases reported to WHO during 2010-2014. Enterovirus 71 (EV71 is responsible for most of the severe HFMD cases. Three EV71 vaccines recently demonstrated good efficacy in children aged 6-71 mo. Here we assessed the cost-effectiveness of routine pediatric EV71 vaccination in China.We characterized the economic and health burden of EV71-associated HFMD (EV71-HFMD in China using (i the national surveillance database, (ii virological surveillance records from all provinces, and (iii a caregiver survey on the household costs and health utility loss for 1,787 laboratory-confirmed pediatric cases. Using a static model parameterized with these data, we estimated the effective vaccine cost (EVC, defined as cost/efficacy or simply the cost of a 100% efficacious vaccine below which routine pediatric vaccination would be considered cost-effective. We performed the base-case analysis from the societal perspective with a willingness-to-pay threshold of one times the gross domestic product per capita (GDPpc and an annual discount rate of 3%. We performed uncertainty analysis by (i accounting for the uncertainty in the risk of EV71-HFMD due to missing laboratory data in the national database, (ii excluding productivity loss of parents and caregivers, (iii increasing the willingness-to-pay threshold to three times GDPpc, (iv increasing the discount rate to 6%, and (v accounting for the proportion of EV71-HFMD cases not registered by national surveillance. In each of these scenarios, we performed probabilistic sensitivity analysis to account for parametric uncertainty in our estimates of the risk of EV71-HFMD and the expected costs and health utility loss due to EV71-HFMD. Routine pediatric EV71 vaccination would be cost-saving if the all-inclusive EVC is below US$10.6 (95% CI US$9.7-US$11.5 and would remain cost-effective if EVC is below US$17.9 (95% CI US$16.9-US$18.8 in

  4. Smart Aquifer Characterisation validated using Information Theory and Cost benefit analysis

    Science.gov (United States)

    Moore, Catherine

    2016-04-01

    The field data acquisition required to characterise aquifer systems are time consuming and expensive. Decisions regarding field testing, the type of field measurements to make and the spatial and temporal resolution of measurements have significant cost repercussions and impact the accuracy of various predictive simulations. The Smart Aquifer Characterisation (SAC) research programme (New Zealand (NZ)) addresses this issue by assembling and validating a suite of innovative methods for characterising groundwater systems at the large, regional and national scales. The primary outcome is a suite of cost effective tools and procedures provided to resource managers to advance the understanding and management of groundwater systems and thereby assist decision makers and communities in the management of their groundwater resources, including the setting of land use limits that protect fresh water flows and quality and the ecosystems dependent on that fresh water. The programme has focused novel investigation approaches including the use of geophysics, satellite remote sensing, temperature sensing and age dating. The SMART (Save Money And Reduce Time) aspect of the programme emphasises techniques that use these passive cost effective data sources to characterise groundwater systems at both the aquifer and the national scale by: • Determination of aquifer hydraulic properties • Determination of aquifer dimensions • Quantification of fluxes between ground waters and surface water • Groundwater age dating These methods allow either a lower cost method for estimating these properties and fluxes, or a greater spatial and temporal coverage for the same cost. To demonstrate the cost effectiveness of the methods a 'data worth' analysis is undertaken. The data worth method involves quantification of the utility of observation data in terms of how much it reduces the uncertainty of model parameters and decision focussed predictions which depend on these parameters. Such

  5. Early prevention of pressure ulcers among elderly patients admitted through emergency departments: a cost-effectiveness analysis.

    Science.gov (United States)

    Pham, Ba'; Teague, Laura; Mahoney, James; Goodman, Laurie; Paulden, Mike; Poss, Jeff; Li, Jianli; Ieraci, Luciano; Carcone, Steven; Krahn, Murray

    2011-11-01

    Every year, approximately 6.2 million hospital admissions through emergency departments (ED) involve elderly patients who are at risk of developing pressure ulcers. We evaluated the cost-effectiveness of pressure-redistribution foam mattresses on ED stretchers and beds for early prevention of pressure ulcers in elderly admitted ED patients. Using a Markov model, we evaluated the incremental effectiveness (quality-adjusted life-days) and incremental cost (hospital and home care costs) between early prevention and current practice (with standard hospital mattresses) from a health care payer perspective during a 1-year time horizon. The projected incidence of ED-acquired pressure ulcers was 1.90% with current practice and 1.48% with early prevention, corresponding to a number needed to treat of 238 patients. The average upgrading cost from standard to pressure-redistribution mattresses was $0.30 per patient. Compared with current practice, early prevention was more effective, with 0.0015 quality-adjusted life-days gained, and less costly, with a mean cost saving of $32 per patient. If decisionmakers are willing to pay $50,000 per quality-adjusted life-year gained, early prevention was cost-effective even for short ED stay (ie, 1 hour), low hospital-acquired pressure ulcer risk (1% prevalence), and high unit price of pressure-redistribution mattresses ($3,775). Taking input uncertainty into account, early prevention was 81% likely to be cost-effective. Expected value-of-information estimates supported additional randomized controlled trials of pressure-redistribution mattresses to eliminate the remaining decision uncertainty. The economic evidence supports early prevention with pressure-redistribution foam mattresses in the ED. Early prevention is likely to improve health for elderly patients and save hospital costs. Copyright © 2011 American College of Emergency Physicians. Published by Mosby, Inc. All rights reserved.

  6. Using cost/risk uncertainty spheres to make better environmental restoration decisions

    International Nuclear Information System (INIS)

    Shangraw, R.F.; Cheney, C.S.; Shangraw, W.R.

    1994-01-01

    The process of balancing cost expenditures and risk reductions during environmental restoration (ER) activities (and as part of other environmental programs such as waste management and facility transition) is the critical policy decision facing DOE site decisionmakers and associated stakeholders (including regulators). The ground rules for this process are specified formally in the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), as amended, the Resource Conservation and Recovery Act, as amended, the subsequent regulations (e.g., National Contingency Plan) and policies that EPA and State agencies have issued to implement these programs, and (increasingly) interagency agreements and orders. Clearly, as Federal resources to meet environmental commitments become more constrained, cost and risk management tradeoffs will become even more needed and their results pronounced

  7. A Quantitative Measure For Evaluating Project Uncertainty Under Variation And Risk Effects

    Directory of Open Access Journals (Sweden)

    A. Chenarani

    2017-10-01

    Full Text Available The effects of uncertainty on a project and the risk event as the consequence of uncertainty are analyzed. The uncertainty index is proposed as a quantitative measure for evaluating the uncertainty of a project. This is done by employing entropy as the indicator of system disorder and lack of information. By employing this index, the uncertainty of each activity and its increase due to risk effects as well as project uncertainty changes as a function of time can be assessed. The results are implemented and analyzed for a small turbojet engine development project as the case study. The results of this study can be useful for project managers and other stakeholders for selecting the most effective risk management and uncertainty controlling method.

  8. An inexact mixed risk-aversion two-stage stochastic programming model for water resources management under uncertainty.

    Science.gov (United States)

    Li, W; Wang, B; Xie, Y L; Huang, G H; Liu, L

    2015-02-01

    Uncertainties exist in the water resources system, while traditional two-stage stochastic programming is risk-neutral and compares the random variables (e.g., total benefit) to identify the best decisions. To deal with the risk issues, a risk-aversion inexact two-stage stochastic programming model is developed for water resources management under uncertainty. The model was a hybrid methodology of interval-parameter programming, conditional value-at-risk measure, and a general two-stage stochastic programming framework. The method extends on the traditional two-stage stochastic programming method by enabling uncertainties presented as probability density functions and discrete intervals to be effectively incorporated within the optimization framework. It could not only provide information on the benefits of the allocation plan to the decision makers but also measure the extreme expected loss on the second-stage penalty cost. The developed model was applied to a hypothetical case of water resources management. Results showed that that could help managers generate feasible and balanced risk-aversion allocation plans, and analyze the trade-offs between system stability and economy.

  9. Designing cost effective water demand management programs in Australia.

    Science.gov (United States)

    White, S B; Fane, S A

    2002-01-01

    This paper describes recent experience with integrated resource planning (IRP) and the application of least cost planning (LCP) for the evaluation of demand management strategies in urban water. Two Australian case studies, Sydney and Northern New South Wales (NSW) are used in illustration. LCP can determine the most cost effective means of providing water services or alternatively the cheapest forms of water conservation. LCP contrasts to a traditional approach of evaluation which looks only at means of increasing supply. Detailed investigation of water usage, known as end-use analysis, is required for LCP. End-use analysis allows both rigorous demand forecasting, and the development and evaluation of conservation strategies. Strategies include education campaigns, increasing water use efficiency and promoting wastewater reuse or rainwater tanks. The optimal mix of conservation strategies and conventional capacity expansion is identified based on levelised unit cost. IRP uses LCP in the iterative process, evaluating and assessing options, investing in selected options, measuring the results, and then re-evaluating options. Key to this process is the design of cost effective demand management programs. IRP however includes a range of parameters beyond least economic cost in the planning process and program designs, including uncertainty, benefit partitioning and implementation considerations.

  10. Uncertainty, loss aversion, and markets for energy efficiency

    International Nuclear Information System (INIS)

    Greene, David L.

    2011-01-01

    Increasing energy efficiency is critical to mitigating greenhouse gas emissions from fossil-fuel combustion, reducing oil dependence, and achieving a sustainable global energy system. The tendency of markets to neglect apparently cost-effective energy efficiency options has been called the 'efficiency gap' or 'energy paradox.' The market for energy efficiency in new, energy-using durable goods, however, appears to have a bias that leads to undervaluation of future energy savings relative to their expected value. This paper argues that the bias is chiefly produced by the combination of substantial uncertainty about the net value of future fuel savings and the loss aversion of typical consumers. This framework relies on the theory of context-dependent preferences. The uncertainty-loss aversion bias against energy efficiency is quantifiable, making it potentially correctible by policy measures. The welfare economics of such policies remains unresolved. Data on the costs of increased fuel economy of new passenger cars, taken from a National Research Council study, illustrate how an apparently cost-effective increase in energy efficiency would be uninteresting to loss-averse consumers.

  11. A methodology for spacecraft technology insertion analysis balancing benefit, cost, and risk

    Science.gov (United States)

    Bearden, David Allen

    Emerging technologies are changing the way space missions are developed and implemented. Technology development programs are proceeding with the goal of enhancing spacecraft performance and reducing mass and cost. However, it is often the case that technology insertion assessment activities, in the interest of maximizing performance and/or mass reduction, do not consider synergistic system-level effects. Furthermore, even though technical risks are often identified as a large cost and schedule driver, many design processes ignore effects of cost and schedule uncertainty. This research is based on the hypothesis that technology selection is a problem of balancing interrelated (and potentially competing) objectives. Current spacecraft technology selection approaches are summarized, and a Methodology for Evaluating and Ranking Insertion of Technology (MERIT) that expands on these practices to attack otherwise unsolved problems is demonstrated. MERIT combines the modern techniques of technology maturity measures, parametric models, genetic algorithms, and risk assessment (cost and schedule) in a unique manner to resolve very difficult issues including: user-generated uncertainty, relationships between cost/schedule and complexity, and technology "portfolio" management. While the methodology is sufficiently generic that it may in theory be applied to a number of technology insertion problems, this research focuses on application to the specific case of small (<500 kg) satellite design. Small satellite missions are of particular interest because they are often developed under rigid programmatic (cost and schedule) constraints and are motivated to introduce advanced technologies into the design. MERIT is demonstrated for programs procured under varying conditions and constraints such as stringent performance goals, not-to-exceed costs, or hard schedule requirements. MERIT'S contributions to the engineering community are its: unique coupling of the aspects of performance

  12. The value of heterogeneity for cost-effectiveness subgroup analysis: conceptual framework and application.

    Science.gov (United States)

    Espinoza, Manuel A; Manca, Andrea; Claxton, Karl; Sculpher, Mark J

    2014-11-01

    This article develops a general framework to guide the use of subgroup cost-effectiveness analysis for decision making in a collectively funded health system. In doing so, it addresses 2 key policy questions, namely, the identification and selection of subgroups, while distinguishing 2 sources of potential value associated with heterogeneity. These are 1) the value of revealing the factors associated with heterogeneity in costs and outcomes using existing evidence (static value) and 2) the value of acquiring further subgroup-related evidence to resolve the uncertainty given the current understanding of heterogeneity (dynamic value). Consideration of these 2 sources of value can guide subgroup-specific treatment decisions and inform whether further research should be conducted to resolve uncertainty to explain variability in costs and outcomes. We apply the proposed methods to a cost-effectiveness analysis for the management of patients with acute coronary syndrome. This study presents the expected net benefits under current and perfect information when subgroups are defined based on the use and combination of 6 binary covariates. The results of the case study confirm the theoretical expectations. As more subgroups are considered, the marginal net benefit gains obtained under the current information show diminishing marginal returns, and the expected value of perfect information shows a decreasing trend. We present a suggested algorithm that synthesizes the results to guide policy. © The Author(s) 2014.

  13. Controlling Healthcare Costs: Just Cost Effectiveness or "Just" Cost Effectiveness?

    Science.gov (United States)

    Fleck, Leonard M

    2018-04-01

    Meeting healthcare needs is a matter of social justice. Healthcare needs are virtually limitless; however, resources, such as money, for meeting those needs, are limited. How then should we (just and caring citizens and policymakers in such a society) decide which needs must be met as a matter of justice with those limited resources? One reasonable response would be that we should use cost effectiveness as our primary criterion for making those choices. This article argues instead that cost-effectiveness considerations must be constrained by considerations of healthcare justice. The goal of this article will be to provide a preliminary account of how we might distinguish just from unjust or insufficiently just applications of cost-effectiveness analysis to some healthcare rationing problems; specifically, problems related to extraordinarily expensive targeted cancer therapies. Unconstrained compassionate appeals for resources for the medically least well-off cancer patients will be neither just nor cost effective.

  14. Some reflections on uncertainty analysis and management

    International Nuclear Information System (INIS)

    Aven, Terje

    2010-01-01

    A guide to quantitative uncertainty analysis and management in industry has recently been issued. The guide provides an overall framework for uncertainty modelling and characterisations, using probabilities but also other uncertainty representations (including the Dempster-Shafer theory). A number of practical applications showing how to use the framework are presented. The guide is considered as an important contribution to the field, but there is a potential for improvements. These relate mainly to the scientific basis and clarification of critical issues, for example, concerning the meaning of a probability and the concept of model uncertainty. A reformulation of the framework is suggested using probabilities as the only representation of uncertainty. Several simple examples are included to motivate and explain the basic ideas of the modified framework.

  15. Inflation and Inflation Uncertainty Revisited: Evidence from Egypt

    Directory of Open Access Journals (Sweden)

    Mesbah Fathy Sharaf

    2015-07-01

    Full Text Available The welfare costs of inflation and inflation uncertainty are well documented in the literature and empirical evidence on the link between the two is sparse in the case of Egypt. This paper investigates the causal relationship between inflation and inflation uncertainty in Egypt using monthly time series data during the period January 1974–April 2015. To endogenously control for any potential structural breaks in the inflation time series, Zivot and Andrews (2002 and Clemente–Montanes–Reyes (1998 unit root tests are used. The inflation–inflation uncertainty relation is modeled by the standard two-step approach as well as simultaneously using various versions of the GARCH-M model to control for any potential feedback effects. The analyses explicitly control for the effect of the Economic Reform and Structural Adjustment Program (ERSAP undertaken by the Egyptian government in the early 1990s, which affected inflation rate and its associated volatility. Results show a high degree of inflation–volatility persistence in the response to inflationary shocks. Granger-causality test along with symmetric and asymmetric GARCH-M models indicate a statistically significant bi-directional positive relationship between inflation and inflation uncertainty, supporting both the Friedman–Ball and the Cukierman–Meltzer hypotheses. The findings are robust to the various estimation methods and model specifications. The findings of this paper support the view of adopting inflation-targeting policy in Egypt, after fulfilling its preconditions, to reduce the welfare cost of inflation and its related uncertainties. Monetary authorities in Egypt should enhance the credibility of monetary policy and attempt to reduce inflation uncertainty, which will help lower inflation rates.

  16. Integrating uncertainty into public energy research and development decisions

    Science.gov (United States)

    Anadón, Laura Díaz; Baker, Erin; Bosetti, Valentina

    2017-05-01

    Public energy research and development (R&D) is recognized as a key policy tool for transforming the world's energy system in a cost-effective way. However, managing the uncertainty surrounding technological change is a critical challenge for designing robust and cost-effective energy policies. The design of such policies is particularly important if countries are going to both meet the ambitious greenhouse-gas emissions reductions goals set by the Paris Agreement and achieve the required harmonization with the broader set of objectives dictated by the Sustainable Development Goals. The complexity of informing energy technology policy requires, and is producing, a growing collaboration between different academic disciplines and practitioners. Three analytical components have emerged to support the integration of technological uncertainty into energy policy: expert elicitations, integrated assessment models, and decision frameworks. Here we review efforts to incorporate all three approaches to facilitate public energy R&D decision-making under uncertainty. We highlight emerging insights that are robust across elicitations, models, and frameworks, relating to the allocation of public R&D investments, and identify gaps and challenges that remain.

  17. Identification and communication of uncertainties of phenomenological models in PSA

    International Nuclear Information System (INIS)

    Pulkkinen, U.; Simola, K.

    2001-11-01

    This report aims at presenting a view upon uncertainty analysis of phenomenological models with an emphasis on the identification and documentation of various types of uncertainties and assumptions in the modelling of the phenomena. In an uncertainty analysis, it is essential to include and document all unclear issues, in order to obtain a maximal coverage of unresolved issues. This holds independently on their nature or type of the issues. The classification of uncertainties is needed in the decomposition of the problem and it helps in the identification of means for uncertainty reduction. Further, an enhanced documentation serves to evaluate the applicability of the results to various risk-informed applications. (au)

  18. Uncertainty and Climate Change

    OpenAIRE

    Berliner, L. Mark

    2003-01-01

    Anthropogenic, or human-induced, climate change is a critical issue in science and in the affairs of humankind. Though the target of substantial research, the conclusions of climate change studies remain subject to numerous uncertainties. This article presents a very brief review of the basic arguments regarding anthropogenic climate change with particular emphasis on uncertainty.

  19. The cost of illness attributable to diabetic foot and cost-effectiveness of secondary prevention in Peru.

    Science.gov (United States)

    Cárdenas, María Kathia; Mirelman, Andrew J; Galvin, Cooper J; Lazo-Porras, María; Pinto, Miguel; Miranda, J Jaime; Gilman, Robert H

    2015-10-26

    Diabetes mellitus is a public health challenge worldwide, and roughly 25% of patients with diabetes in developing countries will develop at least one foot ulcer during their lifetime. The gravest outcome of an ulcerated foot is amputation, leading to premature death and larger economic costs. This study aimed to estimate the economic costs of diabetic foot in high-risk patients in Peru in 2012 and to model the cost-effectiveness of a year-long preventive strategy for foot ulceration including: sub-optimal care (baseline), standard care as recommended by the International Diabetes Federation, and standard care plus daily self-monitoring of foot temperature. A decision tree model using a population prevalence-based approach was used to calculate the costs and the incremental cost-effectiveness ratio (ICER). Outcome measures were deaths and major amputations, uncertainty was tested with a one-way sensitivity analysis. The direct costs for prevention and management with sub-optimal care for high-risk diabetics is around US$74.5 million dollars in a single year, which decreases to US$71.8 million for standard care and increases to US$96.8 million for standard care plus temperature monitoring. The implementation of a standard care strategy would avert 791 deaths and is cost-saving in comparison to sub-optimal care. For standard care plus temperature monitoring compared to sub-optimal care the ICER rises to US$16,124 per death averted and averts 1,385 deaths. Diabetic foot complications are highly costly and largely preventable in Peru. The implementation of a standard care strategy would lead to net savings and avert deaths over a one-year period. More intensive prevention strategies such as incorporating temperature monitoring may also be cost-effective.

  20. Adoption of residential solar power under uncertainty: Implications for renewable energy incentives

    International Nuclear Information System (INIS)

    Bauner, Christoph; Crago, Christine L.

    2015-01-01

    Many incentives at the state and federal level exist for household adoption of renewable energy like solar photovoltaic (PV) panels. Despite generous financial incentives the adoption rate is low. We use the option value framework, which takes into account the benefit of delaying investment in response to uncertainty, to examine the decision by households to invest in solar PV. Using a simulation model, we determine optimal adoption times, critical values of discounted benefits, and adoption rates over time for solar PV investments using data from Massachusetts. We find that the option value multiplier is 1.6, which implies that the discounted value of benefits from solar PV needs to exceed installation cost by 60% for investment to occur. Without any policies, median adoption time is eight years longer under the option value decision rule compared to the net present value decision rule where households equate discounted benefits to installation cost. Rebates and other financial incentives decrease adoption time, but their effect is attenuated if households apply the option value decision rule to solar PV investments. Results suggest that policies that reduce the uncertainty in returns from solar PV investments would be most effective at incentivizing adoption. - Highlights: • We examine household adoption of solar PV using the option value framework. • Uncertainty in benefits and costs leads to delay in investment timing. • Discounted benefits from solar PV have to exceed investment cost by 60% to trigger investment. • Policy incentives that reduce uncertainty in returns from solar PV are most effective.

  1. Costs and cost-effectiveness of training traditional birth attendants to reduce neonatal mortality in the Lufwanyama Neonatal Survival study (LUNESP).

    Science.gov (United States)

    Sabin, Lora L; Knapp, Anna B; MacLeod, William B; Phiri-Mazala, Grace; Kasimba, Joshua; Hamer, Davidson H; Gill, Christopher J

    2012-01-01

    The Lufwanyama Neonatal Survival Project ("LUNESP") was a cluster randomized, controlled trial that showed that training traditional birth attendants (TBAs) to perform interventions targeting birth asphyxia, hypothermia, and neonatal sepsis reduced all-cause neonatal mortality by 45%. This companion analysis was undertaken to analyze intervention costs and cost-effectiveness, and factors that might improve cost-effectiveness. We calculated LUNESP's financial and economic costs and the economic cost of implementation for a forecasted ten-year program (2011-2020). In each case, we calculated the incremental cost per death avoided and disability-adjusted life years (DALYs) averted in real 2011 US dollars. The forecasted 10-year program analysis included a base case as well as 'conservative' and 'optimistic' scenarios. Uncertainty was characterized using one-way sensitivity analyses and a multivariate probabilistic sensitivity analysis. The estimated financial and economic costs of LUNESP were $118,574 and $127,756, respectively, or $49,469 and $53,550 per year. Fixed costs accounted for nearly 90% of total costs. For the 10-year program, discounted total and annual program costs were $256,455 and $26,834 respectively; for the base case, optimistic, and conservative scenarios, the estimated cost per death avoided was $1,866, $591, and $3,024, and cost per DALY averted was $74, $24, and $120, respectively. Outcomes were robust to variations in local costs, but sensitive to variations in intervention effect size, number of births attended by TBAs, and the extent of foreign consultants' participation. Based on established guidelines, the strategy of using trained TBAs to reduce neonatal mortality was 'highly cost effective'. We strongly recommend consideration of this approach for other remote rural populations with limited access to health care.

  2. The economic costs of energy

    International Nuclear Information System (INIS)

    Brookes, L.G.

    1980-01-01

    At a recent symposium, the economic costs of nuclear power were examined in four lectures which considered; (1) The performance of different types, size and ages of nuclear power plants. (2) The comparison between coal and nuclear power costs based on the principle of net effective cash. (3) The capital requirements of a nuclear programme. (4) The comparative costs, now and in the future, of coal-fired and nuclear plants. It is concluded that uncertainties seem to get greater rather than smaller with time probably due to the high and fluctuating world inflation rates and the great uncertainty about world economic performance introduced by the politicising of world oil supplies. (UK)

  3. A Peep into the Uncertainty-Complexity-Relevance Modeling Trilemma through Global Sensitivity and Uncertainty Analysis

    Science.gov (United States)

    Munoz-Carpena, R.; Muller, S. J.; Chu, M.; Kiker, G. A.; Perz, S. G.

    2014-12-01

    Model Model complexity resulting from the need to integrate environmental system components cannot be understated. In particular, additional emphasis is urgently needed on rational approaches to guide decision making through uncertainties surrounding the integrated system across decision-relevant scales. However, in spite of the difficulties that the consideration of modeling uncertainty represent for the decision process, it should not be avoided or the value and science behind the models will be undermined. These two issues; i.e., the need for coupled models that can answer the pertinent questions and the need for models that do so with sufficient certainty, are the key indicators of a model's relevance. Model relevance is inextricably linked with model complexity. Although model complexity has advanced greatly in recent years there has been little work to rigorously characterize the threshold of relevance in integrated and complex models. Formally assessing the relevance of the model in the face of increasing complexity would be valuable because there is growing unease among developers and users of complex models about the cumulative effects of various sources of uncertainty on model outputs. In particular, this issue has prompted doubt over whether the considerable effort going into further elaborating complex models will in fact yield the expected payback. New approaches have been proposed recently to evaluate the uncertainty-complexity-relevance modeling trilemma (Muller, Muñoz-Carpena and Kiker, 2011) by incorporating state-of-the-art global sensitivity and uncertainty analysis (GSA/UA) in every step of the model development so as to quantify not only the uncertainty introduced by the addition of new environmental components, but the effect that these new components have over existing components (interactions, non-linear responses). Outputs from the analysis can also be used to quantify system resilience (stability, alternative states, thresholds or tipping

  4. Communicating uncertainty media coverage of new and controversial science

    CERN Document Server

    Dunwoody, Sharon; Rogers, Carol L

    1997-01-01

    This work, by the editors of "Scientists and Journalists: Reporting Science as News", explores scientific uncertainty and media coverage of it in such major public issues as AISA, biotechnology, dioxin, global warming, and nature vs. nurture. It examines the interrelations of the major actors in constructing and explaining uncertainty: scientists, journalists, scholars, and the larger public. Part 1 examines participants in the scientific uncertainty arena and how the major actors react to, cope with and manage uncertain issues. It also describes how scientists and journalists vie for control over uncertain science. The panel discussion at the end of this section is a spirited discourse on how they handle scientific uncertainty. Part 2 explores instances of scientific uncertainty in the public arena, highlighting studies involving uncertainty and biotechnology, dioxin, human resources for science, and human behaviour. The panel discussion concluding this section reacts to several of these specific issues and ...

  5. Uncertainty quantification of CO2 emission reduction for maritime shipping

    International Nuclear Information System (INIS)

    Yuan, Jun; Ng, Szu Hui; Sou, Weng Sut

    2016-01-01

    The International Maritime Organization (IMO) has recently proposed several operational and technical measures to improve shipping efficiency and reduce the greenhouse gases (GHG) emissions. The abatement potentials estimated for these measures have been further used by many organizations to project future GHG emission reductions and plot Marginal Abatement Cost Curves (MACC). However, the abatement potentials estimated for many of these measures can be highly uncertain as many of these measures are new, with limited sea trial information. Furthermore, the abatements obtained are highly dependent on ocean conditions, trading routes and sailing patterns. When the estimated abatement potentials are used for projections, these ‘input’ uncertainties are often not clearly displayed or accounted for, which can lead to overly optimistic or pessimistic outlooks. In this paper, we propose a methodology to systematically quantify and account for these input uncertainties on the overall abatement potential forecasts. We further propose improvements to MACCs to better reflect the uncertainties in marginal abatement costs and total emissions. This approach provides a fuller and more accurate picture of abatement forecasts and potential reductions achievable, and will be useful to policy makers and decision makers in the shipping industry to better assess the cost effective measures for CO 2 emission reduction. - Highlights: • We propose a systematic method to quantify uncertainty in emission reduction. • Marginal abatement cost curves are improved to better reflect the uncertainties. • Percentage reduction probability is given to determine emission reduction target. • The methodology is applied to a case study on maritime shipping.

  6. Pursuing Photovoltaic Cost-Effectiveness

    DEFF Research Database (Denmark)

    Yang, Yongheng; Koutroulis, Eftichios; Sangwongwanich, Ariya

    2017-01-01

    loading of the power devices. However, its feasibility is challenged by the associated energy losses. An increase of the inverter lifetime and a reduction of the energy yield can alter the cost of energy, demanding an optimization of the power limitation. Therefore, aiming at minimizing the Levelized Cost...... be flexibly performed. As an advanced control strategy, the Absolute Active Power Control (AAPC) can effectively solve the overloading issues by limiting the maximum possible PV power to a certain level (i.e., the power limitation), and also benefit the inverter reliability due to the reduction in the thermal...... performance in terms of LCOE and energy production can be obtained by enabling the AAPC strategy, compared to the conventional PV inverter operating only in the maximum power point tracking mode. In the presented case study, the minimum of the LCOE is achieved for the PV system when the power limit...

  7. Summary from the epistemic uncertainty workshop: consensus amid diversity

    International Nuclear Information System (INIS)

    Ferson, Scott; Joslyn, Cliff A.; Helton, Jon C.; Oberkampf, William L.; Sentz, Kari

    2004-01-01

    The 'Epistemic Uncertainty Workshop' sponsored by Sandia National Laboratories was held in Albuquerque, New Mexico, on 6-7 August 2002. The workshop was organized around a set of Challenge Problems involving both epistemic and aleatory uncertainty that the workshop participants were invited to solve and discuss. This concluding article in a special issue of Reliability Engineering and System Safety based on the workshop discusses the intent of the Challenge Problems, summarizes some discussions from the workshop, and provides a technical comparison among the papers in this special issue. The Challenge Problems were computationally simple models that were intended as vehicles for the illustration and comparison of conceptual and numerical techniques for use in analyses that involve: (i) epistemic uncertainty, (ii) aggregation of multiple characterizations of epistemic uncertainty, (iii) combination of epistemic and aleatory uncertainty, and (iv) models with repeated parameters. There was considerable diversity of opinion at the workshop about both methods and fundamental issues, and yet substantial consensus about what the answers to the problems were, and even about how each of the four issues should be addressed. Among the technical approaches advanced were probability theory, Dempster-Shafer evidence theory, random sets, sets of probability measures, imprecise coherent probabilities, coherent lower previsions, probability boxes, possibility theory, fuzzy sets, joint distribution tableaux, polynomial chaos expansions, and info-gap models. Although some participants maintained that a purely probabilistic approach is fully capable of accounting for all forms of uncertainty, most agreed that the treatment of epistemic uncertainty introduces important considerations and that the issues underlying the Challenge Problems are legitimate and significant. Topics identified as meriting additional research include elicitation of uncertainty representations, aggregation of

  8. Cost-Effectiveness Analysis of Six Strategies to Treat Recurrent Clostridium difficile Infection.

    Directory of Open Access Journals (Sweden)

    Lauren Lapointe-Shaw

    Full Text Available To assess the cost-effectiveness of six treatment strategies for patients diagnosed with recurrent Clostridium difficile infection (CDI in Canada: 1. oral metronidazole; 2. oral vancomycin; 3.oral fidaxomicin; 4. fecal transplantation by enema; 5. fecal transplantation by nasogastric tube; and 6. fecal transplantation by colonoscopy.Public insurer for all hospital and physician services.Ontario, Canada.A decision analytic model was used to model costs and lifetime health effects of each strategy for a typical patient experiencing up to three recurrences, over 18 weeks. Recurrence data and utilities were obtained from published sources. Cost data was obtained from published sources and hospitals in Toronto, Canada. The willingness-to-pay threshold was $50,000/QALY gained.Fecal transplantation by colonoscopy dominated all other strategies in the base case, as it was less costly and more effective than all alternatives. After accounting for uncertainty in all model parameters, there was an 87% probability that fecal transplantation by colonoscopy was the most beneficial strategy. If colonoscopy was not available, fecal transplantation by enema was cost-effective at $1,708 per QALY gained, compared to metronidazole. In addition, fecal transplantation by enema was the preferred strategy if the probability of recurrence following this strategy was below 8.7%. If fecal transplantation by any means was unavailable, fidaxomicin was cost-effective at an additional cost of $25,968 per QALY gained, compared to metronidazole.Fecal transplantation by colonoscopy (or enema, if colonoscopy is unavailable is cost-effective for treating recurrent CDI in Canada. Where fecal transplantation is not available, fidaxomicin is also cost-effective.

  9. Cost-Effectiveness Analysis of Six Strategies to Treat Recurrent Clostridium difficile Infection.

    Science.gov (United States)

    Lapointe-Shaw, Lauren; Tran, Kim L; Coyte, Peter C; Hancock-Howard, Rebecca L; Powis, Jeff; Poutanen, Susan M; Hota, Susy

    2016-01-01

    To assess the cost-effectiveness of six treatment strategies for patients diagnosed with recurrent Clostridium difficile infection (CDI) in Canada: 1. oral metronidazole; 2. oral vancomycin; 3.oral fidaxomicin; 4. fecal transplantation by enema; 5. fecal transplantation by nasogastric tube; and 6. fecal transplantation by colonoscopy. Public insurer for all hospital and physician services. Ontario, Canada. A decision analytic model was used to model costs and lifetime health effects of each strategy for a typical patient experiencing up to three recurrences, over 18 weeks. Recurrence data and utilities were obtained from published sources. Cost data was obtained from published sources and hospitals in Toronto, Canada. The willingness-to-pay threshold was $50,000/QALY gained. Fecal transplantation by colonoscopy dominated all other strategies in the base case, as it was less costly and more effective than all alternatives. After accounting for uncertainty in all model parameters, there was an 87% probability that fecal transplantation by colonoscopy was the most beneficial strategy. If colonoscopy was not available, fecal transplantation by enema was cost-effective at $1,708 per QALY gained, compared to metronidazole. In addition, fecal transplantation by enema was the preferred strategy if the probability of recurrence following this strategy was below 8.7%. If fecal transplantation by any means was unavailable, fidaxomicin was cost-effective at an additional cost of $25,968 per QALY gained, compared to metronidazole. Fecal transplantation by colonoscopy (or enema, if colonoscopy is unavailable) is cost-effective for treating recurrent CDI in Canada. Where fecal transplantation is not available, fidaxomicin is also cost-effective.

  10. Cost Effectiveness of Monoclonal Antibody Therapy for Rare Diseases: A Systematic Review.

    Science.gov (United States)

    Park, Taehwan; Griggs, Scott K; Suh, Dong-Churl

    2015-08-01

    Monoclonal antibody (mAb)-based orphan drugs have led to advances in the treatment of diseases by selectively targeting molecule functions. However, their high treatment costs impose a substantial cost burden on patients and society. The study aimed to systematically review cost-effectiveness evidence of mAb orphan drugs. Ovid MEDLINE(®), EMBASE(®), and PsycINFO(®) were searched in June 2014 and articles were selected if they conducted economic evaluations of the mAb orphan drugs that had received marketing approval in the USA. The quality of the selected studies was assessed using the Quality of Health Economic Studies (QHES) instrument. We reviewed 16 articles that included 24 economic evaluations of nine mAb orphan drugs. Six of these nine drugs were included in cost-utility analysis studies, whereas three drugs were included in cost-effectiveness analysis studies. Previous cost-utility analysis studies revealed that four mAb orphan drugs (cetuximab, ipilimumab, rituximab, and trastuzumab) were found to be cost effective; one drug (bevacizumab) was not cost effective; and one drug (infliximab) was not consistent across the studies. Prior cost-effectiveness analysis studies which included three mAb orphan drugs (adalimumab, alemtuzumab, and basiliximab) showed that the incremental cost per effectiveness gained for these drugs ranged from $US4669 to $Can52,536 Canadian dollars. The quality of the included studies was good or fair with the exception of one study. Some mAb orphan drugs were reported as cost effective under the current decision-making processes. Use of these expensive drugs, however, can raise an equity issue which concerns fairness in access to treatment. The issue of equal access to drugs needs to be considered alongside other societal values in making the final health policy decisions.

  11. Planning nuclear energy centers under technological and demand uncertainty

    International Nuclear Information System (INIS)

    Meier, P.M.; Palmedo, P.F.

    1976-01-01

    The question considered is whether new nuclear power plants should be located in nuclear energy centers, or ''power parks'' with co-located fabrication and reprocessing facilities. That issue has been addressed in a recent study by the Nuclear Regulatory Commission and remains under investigation at Brookhaven and elsewhere. So far, however, the advisability of this policy has been analyzed primarily within the framework of a single view of the future. Suggestions of the types of questions that should be asked regarding this policy if it is properly to be viewed as an example of decision making under uncertainty are made. It is concluded that ''A consideration of the various uncertainties involved in the question of dispersed vs. remote siting of energy facilities introduces a number of new elements into the analysis. On balance those considerations provide somewhat greater support for the clustered concept. The NEC approach seems to provide somewhat greater flexibility in accomodating possible future electricity generating technologies. Increased regulatory and construction efficiencies possible in an NEC reduces the impact of demand uncertainty as does the lower costs associated with construction acceleration or deceleration.'' It is also noted that, in the final analysis, ''it is the public's perception of the relative costs and benefits of a measure that determine the acceptability or unacceptability of a particular innovation,'' not the engineer's cost/benefit analysis. It is further noted that if the analysis can identify limits on analytical methods and models, it will not make the job of energy decision-making any easier, but it may make the process more responsive to its impact on society

  12. Can delivery systems use cost-effectiveness analysis to reduce healthcare costs and improve value?

    Science.gov (United States)

    Savitz, Lucy A; Savitz, Samuel T

    2016-01-01

    Understanding costs and ensuring that we demonstrate value in healthcare is a foundational presumption as we transform the way we deliver and pay for healthcare in the U.S. With a focus on population health and payment reforms underway, there is increased pressure to examine cost-effectiveness in healthcare delivery. Cost-effectiveness analysis (CEA) is a type of economic analysis comparing the costs and effects (i.e. health outcomes) of two or more treatment options. The result is expressed as a ratio where the denominator is the gain in health from a measure (e.g. years of life or quality-adjusted years of life) and the numerator is the incremental cost associated with that health gain. For higher cost interventions, the lower the ratio of costs to effects, the higher the value. While CEA is not new, the approach continues to be refined with enhanced statistical techniques and standardized methods. This article describes the CEA approach and also contrasts it to optional approaches, in order for readers to fully appreciate caveats and concerns. CEA as an economic evaluation tool can be easily misused owing to inappropriate assumptions, over reliance, and misapplication. Twelve issues to be considered in using CEA results to drive healthcare delivery decision-making are summarized. Appropriately recognizing both the strengths and the limitations of CEA is necessary for informed resource allocation in achieving the maximum value for healthcare services provided.

  13. Differential effects of uncertainty on LPP responses to emotional events during explicit and implicit anticipation.

    Science.gov (United States)

    Lin, Huiyan; Liang, Jiafeng; Jin, Hua; Zhao, Dongmei

    2018-07-01

    Previous studies have investigated whether uncertainty influences neural responses to emotional events. The findings of such studies, particularly with respect to event-related potentials (ERPs), have been controversial due to several factors, such as the stimuli that serve as cues and the emotional content of the events. However, it is still unknown whether the effects of uncertainty on ERP responses to emotional events are influenced by anticipation patterns (e.g., explicit or implicit anticipation). To address this issue, participants in the present study were presented with anticipatory cues and then emotional (negative and neutral) pictures. The cues either did or did not signify the emotional content of the upcoming picture. In the inter-stimulus intervals between cues and pictures, participants were asked to estimate the expected probability of the occurrence of a specific emotional category of the subsequent picture based on a scale in the explicit anticipation condition, while in the implicit condition, participants were asked to indicate, using a number on a scale, which color was different from the others. The results revealed that in the explicit condition, uncertainty increased late positive potential (LPP) responses, particularly for negative pictures, whereas LPP responses were larger for certain negative pictures than for uncertain negative pictures in the implicit condition. The findings in the present study suggest that the anticipation pattern influences the effects of uncertainty when evaluation of negative events. Copyright © 2018 Elsevier B.V. All rights reserved.

  14. Cost-effectiveness of a nurse practitioner-family physician model of care in a nursing home: controlled before and after study.

    Science.gov (United States)

    Lacny, Sarah; Zarrabi, Mahmood; Martin-Misener, Ruth; Donald, Faith; Sketris, Ingrid; Murphy, Andrea L; DiCenso, Alba; Marshall, Deborah A

    2016-09-01

    To examine the cost-effectiveness of a nurse practitioner-family physician model of care compared with family physician-only care in a Canadian nursing home. As demand for long-term care increases, alternative care models including nurse practitioners are being explored. Cost-effectiveness analysis using a controlled before-after design. The study included an 18-month 'before' period (2005-2006) and a 21-month 'after' time period (2007-2009). Data were abstracted from charts from 2008-2010. We calculated incremental cost-effectiveness ratios comparing the intervention (nurse practitioner-family physician model; n = 45) to internal (n = 65), external (n = 70) and combined internal/external family physician-only control groups, measured as the change in healthcare costs divided by the change in emergency department transfers/person-month. We assessed joint uncertainty around costs and effects using non-parametric bootstrapping and cost-effectiveness acceptability curves. Point estimates of the incremental cost-effectiveness ratio demonstrated the nurse practitioner-family physician model dominated the internal and combined control groups (i.e. was associated with smaller increases in costs and emergency department transfers/person-month). Compared with the external control, the intervention resulted in a smaller increase in costs and larger increase in emergency department transfers. Using a willingness-to-pay threshold of $1000 CAD/emergency department transfer, the probability the intervention was cost-effective compared with the internal, external and combined control groups was 26%, 21% and 25%. Due to uncertainty around the distribution of costs and effects, we were unable to make a definitive conclusion regarding the cost-effectiveness of the nurse practitioner-family physician model; however, these results suggest benefits that could be confirmed in a larger study. © 2016 John Wiley & Sons Ltd.

  15. A prioritization of generic safety issues

    International Nuclear Information System (INIS)

    Emrit, R.; Riggs, R.; Milstead, W.; Pittman, J.

    1991-07-01

    This report presents the priority rankings for generic safety issues and related to nuclear power plants. The purpose of these rankings is to assist in the timely and efficient allocation of NRC resources for the resolution of those safety issues that have a significant potential for reducing risk. The report focuses on the prioritization of generic safety issues. Issues primarily concerned with the licensing process or environmental protection and not directly related to safety have been excluded from prioritization. The prioritized issues include: TMI Action Plan items under development; previously proposed issues covered by Task Action Plans, except issues designated as Un-resolved Safety Issues (USIs) which had already been assigned high priority; and newly-proposed issues. Future supplements to this report will include the prioritization of additional issues. The safety priority rankings are High, Medium, Low, and Drop and have been assigned on the basis of risk significance estimates, the ratio of risk to costs and other impacts estimated to result if resolutions of the safety issues were implemented, and the consideration of uncertainties and other quantitative or qualitative factors. To the extent practical, estimates are quantitative. 1310 refs

  16. Uncertainties in effective dose estimates of adult CT head scans: The effect of head size

    International Nuclear Information System (INIS)

    Gregory, Kent J.; Bibbo, Giovanni; Pattison, John E.

    2009-01-01

    Purpose: This study is an extension of a previous study where the uncertainties in effective dose estimates from adult CT head scans were calculated using four CT effective dose estimation methods, three of which were computer programs (CT-EXPO, CTDOSIMETRY, and IMPACTDOSE) and one that involved the dose length product (DLP). However, that study did not include the uncertainty contribution due to variations in head sizes. Methods: The uncertainties due to head size variations were estimated by first using the computer program data to calculate doses to small and large heads. These doses were then compared with doses calculated for the phantom heads used by the computer programs. An uncertainty was then assigned based on the difference between the small and large head doses and the doses of the phantom heads. Results: The uncertainties due to head size variations alone were found to be between 4% and 26% depending on the method used and the patient gender. When these uncertainties were included with the results of the previous study, the overall uncertainties in effective dose estimates (stated at the 95% confidence interval) were 20%-31% (CT-EXPO), 15%-30% (CTDOSIMETRY), 20%-36% (IMPACTDOSE), and 31%-40% (DLP). Conclusions: For the computer programs, the lower overall uncertainties were still achieved when measured values of CT dose index were used rather than tabulated values. For DLP dose estimates, head size variations made the largest (for males) and second largest (for females) contributions to effective dose uncertainty. An improvement in the uncertainty of the DLP method dose estimates will be achieved if head size variation can be taken into account.

  17. Uncertainties in effective dose estimates of adult CT head scans: The effect of head size

    Energy Technology Data Exchange (ETDEWEB)

    Gregory, Kent J.; Bibbo, Giovanni; Pattison, John E. [Department of Medical Physics, Royal Adelaide Hospital, Adelaide, South Australia 5000 (Australia) and School of Electrical and Information Engineering (Applied Physics), University of South Australia, Mawson Lakes, South Australia 5095 (Australia); Division of Medical Imaging, Women' s and Children' s Hospital, North Adelaide, South Australia 5006 (Australia) and School of Electrical and Information Engineering (Applied Physics), University of South Australia, Mawson Lakes, South Australia 5095 (Australia); School of Electrical and Information Engineering (Applied Physics), University of South Australia, Mawson Lakes, South Australia 5095 (Australia)

    2009-09-15

    Purpose: This study is an extension of a previous study where the uncertainties in effective dose estimates from adult CT head scans were calculated using four CT effective dose estimation methods, three of which were computer programs (CT-EXPO, CTDOSIMETRY, and IMPACTDOSE) and one that involved the dose length product (DLP). However, that study did not include the uncertainty contribution due to variations in head sizes. Methods: The uncertainties due to head size variations were estimated by first using the computer program data to calculate doses to small and large heads. These doses were then compared with doses calculated for the phantom heads used by the computer programs. An uncertainty was then assigned based on the difference between the small and large head doses and the doses of the phantom heads. Results: The uncertainties due to head size variations alone were found to be between 4% and 26% depending on the method used and the patient gender. When these uncertainties were included with the results of the previous study, the overall uncertainties in effective dose estimates (stated at the 95% confidence interval) were 20%-31% (CT-EXPO), 15%-30% (CTDOSIMETRY), 20%-36% (IMPACTDOSE), and 31%-40% (DLP). Conclusions: For the computer programs, the lower overall uncertainties were still achieved when measured values of CT dose index were used rather than tabulated values. For DLP dose estimates, head size variations made the largest (for males) and second largest (for females) contributions to effective dose uncertainty. An improvement in the uncertainty of the DLP method dose estimates will be achieved if head size variation can be taken into account.

  18. Nuclear energy: the real cost

    International Nuclear Information System (INIS)

    Spencer, K.; Marshall, R.; Sweet, C.; Prior, M.; Welsh, I.; Bunyard, P.; Goldsmith, E.; Hildyard, N.; Jeffery, J.W.

    1981-01-01

    This report on the discussions within a small group of academics falls under the headings: chairman's foreword; summary and recommendations; the government's nuclear power programme and its implications; the CEGB's planning record; the past performance of Britain's nuclear power stations - a guide for the future (query); nuclear power -early uncertainties; historic costs - 'the fraud inherent in all inflationary finance'; current cost accounting; fuel costs - coal stays steady, nuclear rises; net effective cost and the rationale for nuclear power; reinterpreting net effective costs; other considerations; conclusions and recommendations; references. (U.K.)

  19. Internet pharmacy: issues of access, quality, costs, and regulation.

    Science.gov (United States)

    Crawford, Stephanie Y

    2003-02-01

    Internet pharmacy has been the focus of heightened interest over the past 3 years since the first major Web site was introduced in the United States. This paper addresses issues pertaining to Internet pharmacies that sell prescriptions and other products to consumers at the retail level. The Internet pharmacy industry has shifted rapidly in the short time span. This paper begins with a summary of historical considerations and the shifting organization of Internet pharmacy. The advantages and disadvantages of online pharmacy practice are listed. Issues of access, quality, and cost are described. The challenges in regulation at the state and federal levels are presented. Advice to consumers is offered regarding the use of Internet pharmacy sites for purchasing prescription drug products.

  20. Effect of information, uncertainty and parameter variability on profits in a queue with various pricing strategies

    Science.gov (United States)

    Sun, Wei; Li, Shiyong

    2014-08-01

    This paper presents an unobservable single-server queueing system with three types of uncertainty, where the service rate, or waiting cost or service quality is random variable that may obtain n(n > 2) values. The information about the realised values of parameters is only known to the server. We are concerned about the server's behaviour: revealing or concealing the information to customers. The n-value assumption and the server's behaviour enable us to consider various pricing strategies. In this paper, we analyse the effect of information and uncertainty on profits and make comparisons between the profits under different pricing strategies. Moreover, as for parameter variability reflected by the number of each parameter's possible choices n, we observe the effect of variable n on all types of profits and find that revealing the parameter information can much more benefit the server with the increase of n.

  1. Can a Costly Intervention Be Cost-effective?

    Science.gov (United States)

    Foster, E. Michael; Jones, Damon

    2009-01-01

    Objectives To examine the cost-effectiveness of the Fast Track intervention, a multi-year, multi-component intervention designed to reduce violence among at-risk children. A previous report documented the favorable effect of intervention on the highest-risk group of ninth-graders diagnosed with conduct disorder, as well as self-reported delinquency. The current report addressed the cost-effectiveness of the intervention for these measures of program impact. Design Costs of the intervention were estimated using program budgets. Incremental cost-effectiveness ratios were computed to determine the cost per unit of improvement in the 3 outcomes measured in the 10th year of the study. Results Examination of the total sample showed that the intervention was not cost-effective at likely levels of policymakers' willingness to pay for the key outcomes. Subsequent analysis of those most at risk, however, showed that the intervention likely was cost-effective given specified willingness-to-pay criteria. Conclusions Results indicate that the intervention is cost-effective for the children at highest risk. From a policy standpoint, this finding is encouraging because such children are likely to generate higher costs for society over their lifetimes. However, substantial barriers to cost-effectiveness remain, such as the ability to effectively identify and recruit such higher-risk children in future implementations. PMID:17088509

  2. Effect of uncertainties on probabilistic-based design capacity of hydrosystems

    Science.gov (United States)

    Tung, Yeou-Koung

    2018-02-01

    Hydrosystems engineering designs involve analysis of hydrometric data (e.g., rainfall, floods) and use of hydrologic/hydraulic models, all of which contribute various degrees of uncertainty to the design process. Uncertainties in hydrosystem designs can be generally categorized into aleatory and epistemic types. The former arises from the natural randomness of hydrologic processes whereas the latter are due to knowledge deficiency in model formulation and model parameter specification. This study shows that the presence of epistemic uncertainties induces uncertainty in determining the design capacity. Hence, the designer needs to quantify the uncertainty features of design capacity to determine the capacity with a stipulated performance reliability under the design condition. Using detention basin design as an example, the study illustrates a methodological framework by considering aleatory uncertainty from rainfall and epistemic uncertainties from the runoff coefficient, curve number, and sampling error in design rainfall magnitude. The effects of including different items of uncertainty and performance reliability on the design detention capacity are examined. A numerical example shows that the mean value of the design capacity of the detention basin increases with the design return period and this relation is found to be practically the same regardless of the uncertainty types considered. The standard deviation associated with the design capacity, when subject to epistemic uncertainty, increases with both design frequency and items of epistemic uncertainty involved. It is found that the epistemic uncertainty due to sampling error in rainfall quantiles should not be ignored. Even with a sample size of 80 (relatively large for a hydrologic application) the inclusion of sampling error in rainfall quantiles resulted in a standard deviation about 2.5 times higher than that considering only the uncertainty of the runoff coefficient and curve number. Furthermore, the

  3. Understanding and reducing statistical uncertainties in nebular abundance determinations

    Science.gov (United States)

    Wesson, R.; Stock, D. J.; Scicluna, P.

    2012-06-01

    Whenever observations are compared to theories, an estimate of the uncertainties associated with the observations is vital if the comparison is to be meaningful. However, many or even most determinations of temperatures, densities and abundances in photoionized nebulae do not quote the associated uncertainty. Those that do typically propagate the uncertainties using analytical techniques which rely on assumptions that generally do not hold. Motivated by this issue, we have developed Nebular Empirical Analysis Tool (NEAT), a new code for calculating chemical abundances in photoionized nebulae. The code carries out a standard analysis of lists of emission lines using long-established techniques to estimate the amount of interstellar extinction, calculate representative temperatures and densities, compute ionic abundances from both collisionally excited lines and recombination lines, and finally to estimate total elemental abundances using an ionization correction scheme. NEATuses a Monte Carlo technique to robustly propagate uncertainties from line flux measurements through to the derived abundances. We show that, for typical observational data, this approach is superior to analytic estimates of uncertainties. NEAT also accounts for the effect of upward biasing on measurements of lines with low signal-to-noise ratio, allowing us to accurately quantify the effect of this bias on abundance determinations. We find not only that the effect can result in significant overestimates of heavy element abundances derived from weak lines, but also that taking it into account reduces the uncertainty of these abundance determinations. Finally, we investigate the effect of possible uncertainties in R, the ratio of selective-to-total extinction, on abundance determinations. We find that the uncertainty due to this parameter is negligible compared to the statistical uncertainties due to typical line flux measurement uncertainties.

  4. Cost of New Technologies in Prostate Cancer Treatment: Systematic Review of Costs and Cost Effectiveness of Robotic-assisted Laparoscopic Prostatectomy, Intensity-modulated Radiotherapy, and Proton Beam Therapy.

    Science.gov (United States)

    Schroeck, Florian Rudolf; Jacobs, Bruce L; Bhayani, Sam B; Nguyen, Paul L; Penson, David; Hu, Jim

    2017-11-01

    Some of the high costs of robot-assisted radical prostatectomy (RARP), intensity-modulated radiotherapy (IMRT), and proton beam therapy may be offset by better outcomes or less resource use during the treatment episode. To systematically review the literature to identify the key economic trade-offs implicit in a particular treatment choice for prostate cancer. We systematically reviewed the literature according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement and protocol. We searched Medline, Embase, and Web of Science for articles published between January 2001 and July 2016, which compared the treatment costs of RARP, IMRT, or proton beam therapy to the standard treatment. We identified 37, nine, and three studies, respectively. RARP is costlier than radical retropubic prostatectomy for hospitals and payers. However, RARP has the potential for a moderate cost advantage for payers and society over a longer time horizon when optimal cancer and quality-of-life outcomes are achieved. IMRT is more expensive from a payer's perspective compared with three-dimensional conformal radiotherapy, but also more cost effective when defined by an incremental cost effectiveness ratio new versus traditional technologies is costlier. However, given the low quality of evidence and the inconsistencies across studies, the precise difference in costs remains unclear. Attempts to estimate whether this increased cost is worth the expense are hampered by the uncertainty surrounding improvements in outcomes, such as cancer control and side effects of treatment. If the new technologies can consistently achieve better outcomes, then they may be cost effective. We review the cost and cost effectiveness of robot-assisted radical prostatectomy, intensity-modulated radiotherapy, and proton beam therapy in prostate cancer treatment. These technologies are costlier than their traditional counterparts. It remains unclear whether their use is associated

  5. 24 CFR 1000.418 - Can grant funds be used to pay costs incurred when issuing notes or other obligations?

    Science.gov (United States)

    2010-04-01

    ... costs incurred when issuing notes or other obligations? 1000.418 Section 1000.418 Housing and Urban... to pay costs incurred when issuing notes or other obligations? Yes. Other costs that can be paid using grant funds include but are not limited to the costs of servicing and trust administration, and...

  6. A systematic review and methodological evaluation of published cost-effectiveness analyses of aromatase inhibitors versus tamoxifen in early stage breast cancer.

    Directory of Open Access Journals (Sweden)

    Ava A John-Baptiste

    Full Text Available BACKGROUND: A key priority in developing policies for providing affordable cancer care is measuring the value for money of new therapies using cost-effectiveness analyses (CEAs. For CEA to be useful it should focus on relevant outcomes and include thorough investigation of uncertainty. Randomized controlled trials (RCTs of five years of aromatase inhibitors (AI versus five years of tamoxifen in the treatment of post-menopausal women with early stage breast cancer, show benefit of AI in terms of disease free survival (DFS but not overall survival (OS and indicate higher risk of fracture with AI. Policy-relevant CEA of AI versus tamoxifen should focus on OS and include analysis of uncertainty over key assumptions. METHODS: We conducted a systematic review of published CEAs comparing an AI to tamoxifen. We searched Ovid MEDLINE, EMBASE, PsychINFO, and the Cochrane Database of Systematic Reviews without language restrictions. We selected CEAs with outcomes expressed as cost per life year or cost per quality adjusted life year (QALY. We assessed quality using the Neumann checklist. Using structured forms two abstractors collected descriptive information, sources of data, baseline assumptions on effectiveness and adverse events, and recorded approaches to assessing parameter uncertainty, methodological uncertainty, and structural uncertainty. RESULTS: We identified 1,622 citations and 18 studies met inclusion criteria. All CE estimates assumed a survival benefit for aromatase inhibitors. Twelve studies performed sensitivity analysis on the risk of adverse events and 7 assumed no additional mortality risk with any adverse event. Sub-group analysis was limited; 6 studies examined older women, 2 examined women with low recurrence risk, and 1 examined women with multiple comorbidities. CONCLUSION: Published CEAs comparing AIs to tamoxifen assumed an OS benefit though none has been shown in RCTs, leading to an overestimate of the cost-effectiveness of AIs

  7. Cost-effectiveness of Human Papilloma Virus (HPV) vaccination in Nigeria: a decision analysis using pragmatic parameter estimates for cost and programme coverage.

    Science.gov (United States)

    Ekwunife, Obinna I; Lhachimi, Stefan K

    2017-12-08

    World Health Organisation recommends routine Human Papilloma Virus (HPV) vaccination for girls when its cost-effectiveness in the country or region has been duly considered. We therefore aimed to evaluate cost-effectiveness of HPV vaccination in Nigeria using pragmatic parameter estimates for cost and programme coverage, i.e. realistically achievable in the studied context. A microsimulation frame-work was used. The natural history for cervical cancer disease was remodelled from a previous Nigerian model-based study. Costing was based on health providers' perspective. Disability adjusted life years attributable to cervical cancer mortality served as benefit estimate. Suitable policy option was obtained by calculating the incremental costs-effectiveness ratio. Probabilistic sensitivity analysis was used to assess parameter uncertainty. One-way sensitivity analysis was used to explore the robustness of the policy recommendation to key parameters alteration. Expected value of perfect information (EVPI) was calculated to determine the expected opportunity cost associated with choosing the optimal scenario or strategy at the maximum cost-effectiveness threshold. Combination of the current scenario of opportunistic screening and national HPV vaccination programme (CS + NV) was the only cost-effective and robust policy option. However, CS + NV scenario was only cost-effective so far the unit cost of HPV vaccine did not exceed $5. EVPI analysis showed that it may be worthwhile to conduct additional research to inform the decision to adopt CS + NV. National HPV vaccination combined with opportunist cervical cancer screening is cost-effective in Nigeria. However, adoption of this strategy should depend on its relative efficiency when compared to other competing new vaccines and health interventions.

  8. Costs and cost-effectiveness of training traditional birth attendants to reduce neonatal mortality in the Lufwanyama Neonatal Survival study (LUNESP.

    Directory of Open Access Journals (Sweden)

    Lora L Sabin

    Full Text Available The Lufwanyama Neonatal Survival Project ("LUNESP" was a cluster randomized, controlled trial that showed that training traditional birth attendants (TBAs to perform interventions targeting birth asphyxia, hypothermia, and neonatal sepsis reduced all-cause neonatal mortality by 45%. This companion analysis was undertaken to analyze intervention costs and cost-effectiveness, and factors that might improve cost-effectiveness.We calculated LUNESP's financial and economic costs and the economic cost of implementation for a forecasted ten-year program (2011-2020. In each case, we calculated the incremental cost per death avoided and disability-adjusted life years (DALYs averted in real 2011 US dollars. The forecasted 10-year program analysis included a base case as well as 'conservative' and 'optimistic' scenarios. Uncertainty was characterized using one-way sensitivity analyses and a multivariate probabilistic sensitivity analysis. The estimated financial and economic costs of LUNESP were $118,574 and $127,756, respectively, or $49,469 and $53,550 per year. Fixed costs accounted for nearly 90% of total costs. For the 10-year program, discounted total and annual program costs were $256,455 and $26,834 respectively; for the base case, optimistic, and conservative scenarios, the estimated cost per death avoided was $1,866, $591, and $3,024, and cost per DALY averted was $74, $24, and $120, respectively. Outcomes were robust to variations in local costs, but sensitive to variations in intervention effect size, number of births attended by TBAs, and the extent of foreign consultants' participation.Based on established guidelines, the strategy of using trained TBAs to reduce neonatal mortality was 'highly cost effective'. We strongly recommend consideration of this approach for other remote rural populations with limited access to health care.

  9. Bevacizumab for Metastatic Colorectal Cancer: A Global Cost-Effectiveness Analysis.

    Science.gov (United States)

    Goldstein, Daniel A; Chen, Qiushi; Ayer, Turgay; Chan, Kelvin K W; Virik, Kiran; Hammerman, Ariel; Brenner, Baruch; Flowers, Christopher R; Hall, Peter S

    2017-06-01

    In the U.S., the addition of bevacizumab to first-line chemotherapy in metastatic colorectal cancer (mCRC) has been demonstrated to provide 0.10 quality-adjusted life years (QALYs) at an incremental cost-effectiveness ratio (ICER) of $571,000/QALY. Due to variability in pricing, value for money may be different in other countries. Our objective was to establish the cost-effectiveness of bevacizumab in mCRC in the U.S., U.K., Canada, Australia, and Israel. We performed the analysis using a previously established Markov model for mCRC. Input data for efficacy, adverse events, and quality of life were considered to be generalizable and therefore identical for all countries. We used country-specific prices for medications, administration, and other health service costs. All costs were converted from local currency to U.S. dollars at the exchange rates in March 2016. We conducted one-way and probabilistic sensitivity analyses (PSA) to assess the model robustness across parameter uncertainties. Base case results demonstrated that the highest ICER was in the U.S. ($571,000/QALY) and the lowest was in Australia ($277,000/QALY). In Canada, the U.K., and Israel, ICERs ranged between $351,000 and $358,000 per QALY. PSA demonstrated 0% likelihood of bevacizumab being cost-effective in any country at a willingness to pay threshold of $150,000 per QALY. The addition of bevacizumab to first-line chemotherapy for mCRC consistently fails to be cost-effective in all five countries. There are large differences in cost-effectiveness between countries. This study provides a framework for analyzing the value of a cancer drug from the perspectives of multiple international payers. The cost-effectiveness of bevacizumab varies significantly between multiple countries. By conventional thresholds, bevacizumab is not cost-effective in metastatic colon cancer in the U.S., the U.K., Australia, Canada, and Israel. © AlphaMed Press 2017.

  10. Optimal sizing of small wind/battery systems considering the DC bus voltage stability effect on energy capture, wind speed variability, and load uncertainty

    International Nuclear Information System (INIS)

    Lujano-Rojas, Juan M.; Dufo-López, Rodolfo; Bernal-Agustín, José L.

    2012-01-01

    Highlights: ► We propose a mathematical model for optimal sizing of small wind energy systems. ► No other previous work has considered all the aspects included in this paper. ► The model considers several parameters about batteries. ► Wind speed variability is considered by means of ARMA model. ► The results show how to minimize the expected energy that is not supplied. - Abstract: In this paper, a mathematical model for stochastic simulation and optimization of small wind energy systems is presented. This model is able to consider the operation of the charge controller, the coulombic efficiency during charge and discharge processes, the influence of temperature on the battery bank capacity, the wind speed variability, and load uncertainty. The joint effect of charge controller operation, ambient temperature, and coulombic efficiency is analyzed in a system installed in Zaragoza (Spain), concluding that if the analysis without considering these factors is carried out, the reliability level of the physical system could be lower than expected, and an increment of 25% in the battery bank capacity would be required to reach a reliability level of 90% in the analyzed case. Also, the effect of the wind speed variability and load uncertainty in the system reliability is analyzed. Finally, the uncertainty in the battery bank lifetime and its effect on the net present cost are discussed. The results showed that, considering uncertainty of 17.5% in the battery bank lifetime calculated using the Ah throughput model, about 12% of uncertainty in the net present cost is expected. The model presented in this research could be a useful stochastic simulation and optimization tool that allows the consideration of important uncertainty factors in techno-economic analysis.

  11. Uncertainty analysis in Titan ionospheric simulated ion mass spectra: unveiling a set of issues for models accuracy improvement

    Science.gov (United States)

    Hébrard, Eric; Carrasco, Nathalie; Dobrijevic, Michel; Pernot, Pascal

    Ion Neutral Mass Spectrometer (INMS) aboard Cassini revealed a rich coupled ion-neutral chemistry in the ionosphere, producing heavy hydrocarbons and nitriles ions. The modeling of such a complex environment is challenging, as it requires a detailed and accurate description of the different relevant processes such as photodissociation cross sections and neutral-neutral reaction rates on one hand, and ionisation cross sections, ion-molecule and recombination reaction rates on the other hand. Underpinning models calculations, each of these processes is parameterized by kinetic constants which, when known, have been studied experimentally and/or theoretically over a range of temperatures and pressures that are most often not representative of Titan's atmosphere. The sizeable experimental and theoretical uncertainties reported in the literature merge therefore with the uncertainties resulting subsequently from the unavoidable estimations or extrapolations to Titan's atmosphere conditions. Such large overall uncertainties have to be accounted for in all resulting inferences most of all to evaluate the quality of the model definition. We have undertaken a systematic study of the uncertainty sources in the simulation of ion mass spectra as recorded by Cassini/INMS in Titan ionosphere during the T5 flyby at 1200 km. Our simulated spectra seem much less affected by the uncertainties on ion-molecule reactions than on neutral-neutral reactions. Photochemical models of Titan's atmosphere are indeed so poorly predictive at high altitudes, in the sense that their computed predictions display such large uncertainties, that we found them to give rise to bimodal and hypersensitive abundance distributions for some major compounds like acetylene C2 H2 and ethylene C2 H4 . We will show to what extent global uncertainty and sensitivity analysis enabled us to identify the causes of this bimodality and to pinpoint the key processes that mostly contribute to limit the accuracy of the

  12. Analysis of uncertainty in modeling perceived risks

    International Nuclear Information System (INIS)

    Melnyk, R.; Sandquist, G.M.

    2005-01-01

    Expanding on a mathematical model developed for quantifying and assessing perceived risks, the distribution functions, variances, and uncertainties associated with estimating the model parameters are quantified. The analytical model permits the identification and assignment of any number of quantifiable risk perception factors that can be incorporated within standard risk methodology. Those risk perception factors associated with major technical issues are modeled using lognormal probability density functions to span the potentially large uncertainty variations associated with these risk perceptions. The model quantifies the logic of public risk perception and provides an effective means for measuring and responding to perceived risks. (authors)

  13. Cost effectiveness analysis of immunotherapy in patients with grass pollen allergic rhinoconjunctivitis in Germany.

    Science.gov (United States)

    Westerhout, K Y; Verheggen, B G; Schreder, C H; Augustin, M

    2012-01-01

    An economic evaluation was conducted to assess the outcomes and costs as well as cost-effectiveness of the following grass-pollen immunotherapies: OA (Oralair; Stallergenes S.A., Antony, France) vs GRZ (Grazax; ALK-Abelló, Hørsholm, Denmark), and ALD (Alk Depot SQ; ALK-Abelló) (immunotherapy agents alongside symptomatic medication) and symptomatic treatment alone for grass pollen allergic rhinoconjunctivitis. The costs and outcomes of 3-year treatment were assessed for a period of 9 years using a Markov model. Treatment efficacy was estimated using an indirect comparison of available clinical trials with placebo as a common comparator. Estimates for immunotherapy discontinuation, occurrence of asthma, health state utilities, drug costs, resource use, and healthcare costs were derived from published sources. The analysis was conducted from the insurant's perspective including public and private health insurance payments and co-payments by insurants. Outcomes were reported as quality-adjusted life years (QALYs) and symptom-free days. The uncertainty around incremental model results was tested by means of extensive deterministic univariate and probabilistic multivariate sensitivity analyses. In the base case analysis the model predicted a cost-utility ratio of OA vs symptomatic treatment of €14,728 per QALY; incremental costs were €1356 (95%CI: €1230; €1484) and incremental QALYs 0.092 (95%CI: 0.052; 0.140). OA was the dominant strategy compared to GRZ and ALD, with estimated incremental costs of -€1142 (95%CI: -€1255; -€1038) and -€54 (95%CI: -€188; €85) and incremental QALYs of 0.015 (95%CI: -0.025; 0.056) and 0.027 (95%CI: -0.022; 0.075), respectively. At a willingness-to-pay threshold of €20,000, the probability of OA being the most cost-effective treatment was predicted to be 79%. Univariate sensitivity analyses show that incremental outcomes were moderately sensitive to changes in efficacy estimates. The main study limitation was the

  14. Reducing the uncertainty in robotic machining by modal analysis

    Science.gov (United States)

    Alberdi, Iñigo; Pelegay, Jose Angel; Arrazola, Pedro Jose; Ørskov, Klaus Bonde

    2017-10-01

    The use of industrial robots for machining could lead to high cost and energy savings for the manufacturing industry. Machining robots offer several advantages respect to CNC machines such as flexibility, wide working space, adaptability and relatively low cost. However, there are some drawbacks that are preventing a widespread adoption of robotic solutions namely lower stiffness, vibration/chatter problems and lower accuracy and repeatability. Normally due to these issues conservative cutting parameters are chosen, resulting in a low material removal rate (MRR). In this article, an example of a modal analysis of a robot is presented. For that purpose the Tap-testing technology is introduced, which aims at maximizing productivity, reducing the uncertainty in the selection of cutting parameters and offering a stable process free from chatter vibrations.

  15. The Cost-Effectiveness of Anterior Cruciate Ligament Reconstruction in Competitive Athletes.

    Science.gov (United States)

    Stewart, Bruce A; Momaya, Amit M; Silverstein, Marc D; Lintner, David

    2017-01-01

    Competitive athletes value the ability to return to competitive play after the treatment of anterior cruciate ligament (ACL) injuries. ACL reconstruction has high success rates for return to play, but some studies indicate that patients may do well with nonoperative physical therapy treatment. To evaluate the cost-effectiveness of the treatment of acute ACL tears with either initial surgical reconstruction or physical therapy in competitive athletes. Economic and decision analysis; Level of evidence, 2. The incremental cost, incremental effectiveness, and incremental cost-effectiveness ratio (ICER) of ACL reconstruction compared with physical therapy were calculated from a cost-effectiveness analysis of ACL reconstruction compared with physical therapy for the initial management of acute ACL injuries in competitive athletes. The ACL reconstruction strategy and the physical therapy strategy were represented as Markov models. Costs and quality-adjusted life-years (QALYs) were evaluated over a 6-year time horizon and were analyzed from a societal perspective. Quality of life and probabilities of clinical outcomes were obtained from the peer-reviewed literature, and costs were compiled from a large academic hospital in the United States. One-way, 2-way, and probabilistic sensitivity analyses were used to assess the effect of uncertainty in variables on the ICER of ACL reconstruction. The ICER of ACL reconstruction compared with physical therapy was $22,702 per QALY gained. The ICER was most sensitive to the quality of life of returning to play or not returning to play, costs, and duration of follow-up but relatively insensitive to the rates and costs of complications, probabilities of return to play for both operative and nonoperative treatments, and discount rate. ACL reconstruction is a cost-effective strategy for competitive athletes with an ACL injury.

  16. Effects of undetected data quality issues on climatological analyses

    Directory of Open Access Journals (Sweden)

    S. Hunziker

    2018-01-01

    Full Text Available Systematic data quality issues may occur at various stages of the data generation process. They may affect large fractions of observational datasets and remain largely undetected with standard data quality control. This study investigates the effects of such undetected data quality issues on the results of climatological analyses. For this purpose, we quality controlled daily observations of manned weather stations from the Central Andean area with a standard and an enhanced approach. The climate variables analysed are minimum and maximum temperature and precipitation. About 40 % of the observations are inappropriate for the calculation of monthly temperature means and precipitation sums due to data quality issues. These quality problems undetected with the standard quality control approach strongly affect climatological analyses, since they reduce the correlation coefficients of station pairs, deteriorate the performance of data homogenization methods, increase the spread of individual station trends, and significantly bias regional temperature trends. Our findings indicate that undetected data quality issues are included in important and frequently used observational datasets and hence may affect a high number of climatological studies. It is of utmost importance to apply comprehensive and adequate data quality control approaches on manned weather station records in order to avoid biased results and large uncertainties.

  17. Cost-Effectiveness Analysis of Six Strategies to Treat Recurrent Clostridium difficile Infection

    Science.gov (United States)

    Lapointe-Shaw, Lauren; Tran, Kim L.; Coyte, Peter C.; Hancock-Howard, Rebecca L.; Powis, Jeff; Poutanen, Susan M.; Hota, Susy

    2016-01-01

    Objective To assess the cost-effectiveness of six treatment strategies for patients diagnosed with recurrent Clostridium difficile infection (CDI) in Canada: 1. oral metronidazole; 2. oral vancomycin; 3.oral fidaxomicin; 4. fecal transplantation by enema; 5. fecal transplantation by nasogastric tube; and 6. fecal transplantation by colonoscopy. Perspective Public insurer for all hospital and physician services. Setting Ontario, Canada. Methods A decision analytic model was used to model costs and lifetime health effects of each strategy for a typical patient experiencing up to three recurrences, over 18 weeks. Recurrence data and utilities were obtained from published sources. Cost data was obtained from published sources and hospitals in Toronto, Canada. The willingness-to-pay threshold was $50,000/QALY gained. Results Fecal transplantation by colonoscopy dominated all other strategies in the base case, as it was less costly and more effective than all alternatives. After accounting for uncertainty in all model parameters, there was an 87% probability that fecal transplantation by colonoscopy was the most beneficial strategy. If colonoscopy was not available, fecal transplantation by enema was cost-effective at $1,708 per QALY gained, compared to metronidazole. In addition, fecal transplantation by enema was the preferred strategy if the probability of recurrence following this strategy was below 8.7%. If fecal transplantation by any means was unavailable, fidaxomicin was cost-effective at an additional cost of $25,968 per QALY gained, compared to metronidazole. Conclusion Fecal transplantation by colonoscopy (or enema, if colonoscopy is unavailable) is cost-effective for treating recurrent CDI in Canada. Where fecal transplantation is not available, fidaxomicin is also cost-effective. PMID:26901316

  18. Implications of higher energy - summary of benefits, issues, commissioning cost, SEU, Cryo, QPS margins, Potential availability issues

    CERN Document Server

    Alemany, R

    2012-01-01

    The LHC is technically almost ready to run at 4 TeV per beam in 2012. Nevertheless, a review of the advantages and disadvantages of such an energy step should be carefully made before taking this decision. There fore, this paper will summarize the benefits from the physics point of view; the potential issues like a possible increase of Single Event Errors , Unidentified Flying Objects, or a significant decrease of the quench margin from beam losses that, all in all , could lead to availability issues, compromising the integrated luminosity. And last but not least, the commissioning cost will be addressed.

  19. Cost effectiveness of recombinant factor VIIa for treatment of intracerebral hemorrhage

    Directory of Open Access Journals (Sweden)

    Eckman Mark H

    2008-05-01

    Full Text Available Abstract Background Phase I/II placebo-controlled clinical trials of recombinant Factor VIIa (rFVIIa suggested that administration of rFVIIa within 4 hours after onset of intracerebral hemorrhage (ICH is safe, limits ICH growth, and improves outcomes. We sought to determine the cost-effectiveness of rFVIIa for acute ICH treatment, using published Phase II data. We hypothesized that rFVIIa would have a low marginal cost-effectiveness ratio (mCER given the poor neurologic outcomes after ICH with conventional management. Methods We performed an incremental cost-effectiveness analysis from the societal perspective, considering conventional management vs. 80 ug/kg rFVIIa treatment for acute ICH cases meeting Phase II inclusion criteria. The time frame for the analysis was 1. 25 years: data from the Phase II trial was used for 90 day outcomes and rFVIIa complications – arterial thromboembolic events (ATE. We assumed no substantial cost differences in care between the two strategies except: 1 cost of rFVIIa (for an 80 mcg/kg dose in an 80 kg patient, assumed cost of $6,408; 2 cost of ATE side effects from rFVIIa (which also decrease quality of life and increase the chance of death; and 3 differential monetary costs of outcomes and their impact on quality of life, including disposition (home vs. nursing home, and outpatient vs. inpatient rehabilitation. Sensitivity analyses were performed to explore uncertainty in parameter estimates, impact of rFVIIa cost, direct cost of neurologic outcomes, probability of ATE, and outcomes after ATE. Results In the "base case", treating ICH with rFVIIa dominates the usual care strategy by being more effective and less costly. rFVIIa maintained a mCER Conclusion Based on data from preliminary trials, treating selected ICH patients with rFVIIa results in lower cost and improved clinical outcomes. This potential cost-effectiveness must be considered in light of the Phase III trial results.

  20. The cost-effectiveness of the Olweus Bullying Prevention Program: Results from a modelling study.

    Science.gov (United States)

    Beckman, Linda; Svensson, Mikael

    2015-12-01

    Exposure to bullying affects around 3-5 percent of adolescents in secondary school and is related to various mental health problems. Many different anti-bullying programmes are currently available, but economic evaluations are lacking. The aim of this study is to identify the cost effectiveness of the Olweus Bullying Prevention Program (OBPP). We constructed a decision-tree model for a Swedish secondary school, using a public payer perspective, and retrieved data on costs and effects from the published literature. Probabilistic sensitivity analysis to reflect the uncertainty in the model was conducted. The base-case analysis showed that using the OBPP to reduce the number of victims of bullying costs 131,250 Swedish kronor (€14,470) per victim spared. Compared to a relevant threshold of the societal value of bullying reduction, this indicates that the programme is cost-effective. Using a relevant willingness-to-pay threshold shows that the OBPP is a cost-effective intervention. Copyright © 2015 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

  1. Operational Issues in the Development of a Cost-Effective Reusable LOX/LH2 Engine

    Science.gov (United States)

    Ballard, Richard O.

    2003-01-01

    The NASA Space Launch Initiative (SLI) was initiated in early 2001 to conduct technology development and to reduce the business and technical risk associated with developing the next-generation reusable launch system. In the field of main propulsion, two LOXLH2 rocket engine systems, the Pratt & Whitney / Aerojet Joint Venture (JV) COBRA and the Rocketdyne RS-83, were funded to develop a safe, economical, and reusable propulsion system. Given that a large-thrust reusable rocket engine program had not been started in the U.S. since 1971, with the Space Shuttle Main Engine (SSME), this provided an opportunity to build on the experience developed on the SSME system, while exploiting advances in technology that had occurred in the intervening 30 years. One facet of engine development that was identified as being especially vital in order to produce an optimal system was in the areas of operability and maintainability. In order to achieve the high levels of performance required by the Space Shuttle, the SSME system is highly complex with very tight tolerances and detailed requirements. Over the lifetime of the SSME program, the engine has required a high level of manpower to support the performance of inspections, maintenance (scheduled and unscheduled) and operations (prelaunch and post-flight). As a consequence, the labor- intensive needs of the SSME provide a significant impact to the overall cost efficiency of the Space Transportation System (STS). One of the strategic goals of the SLI is to reduce cost by requiring the engine(s) to be easier (Le. less expensive) to operate and maintain. The most effective means of accomplishing this goal is to infuse the operability and maintainability features into the engine design from the start. This paper discusses some of the operational issues relevant to a reusable LOx/LH2 main engine, and the means by which their impact is mitigated in the design phase.

  2. Cost-effectiveness of emergency contraception options over 1 year.

    Science.gov (United States)

    Bellows, Brandon K; Tak, Casey R; Sanders, Jessica N; Turok, David K; Schwarz, Eleanor B

    2018-05-01

    The copper intrauterine device is the most effective form of emergency contraception and can also provide long-term contraception. The levonorgestrel intrauterine device has also been studied in combination with oral levonorgestrel for women seeking emergency contraception. However, intrauterine devices have higher up-front costs than oral methods, such as ulipristal acetate and levonorgestrel. Health care payers and decision makers (eg, health care insurers, government programs) with financial constraints must determine if the increased effectiveness of intrauterine device emergency contraception methods are worth the additional costs. We sought to compare the cost-effectiveness of 4 emergency contraception strategies-ulipristal acetate, oral levonorgestrel, copper intrauterine device, and oral levonorgestrel plus same-day levonorgestrel intrauterine device-over 1 year from a US payer perspective. Costs (2017 US dollars) and pregnancies were estimated over 1 year using a Markov model of 1000 women seeking emergency contraception. Every 28-day cycle, the model estimated the predicted number of pregnancy outcomes (ie, live birth, ectopic pregnancy, spontaneous abortion, or induced abortion) resulting from emergency contraception failure and subsequent contraception use. Model inputs were derived from published literature and national sources. An emergency contraception strategy was considered cost-effective if the incremental cost-effectiveness ratio (ie, the cost to prevent 1 additional pregnancy) was less than the weighted average cost of pregnancy outcomes in the United States ($5167). The incremental cost-effectiveness ratios and probability of being the most cost-effective emergency contraception strategy were calculated from 1000 probabilistic model iterations. One-way sensitivity analyses were used to examine uncertainty in the cost of emergency contraception, subsequent contraception, and pregnancy outcomes as well as the model probabilities. In 1000 women

  3. Optimization Under Uncertainty of Site-Specific Turbine Configurations

    Science.gov (United States)

    Quick, J.; Dykes, K.; Graf, P.; Zahle, F.

    2016-09-01

    Uncertainty affects many aspects of wind energy plant performance and cost. In this study, we explore opportunities for site-specific turbine configuration optimization that accounts for uncertainty in the wind resource. As a demonstration, a simple empirical model for wind plant cost of energy is used in an optimization under uncertainty to examine how different risk appetites affect the optimal selection of a turbine configuration for sites of different wind resource profiles. If there is unusually high uncertainty in the site wind resource, the optimal turbine configuration diverges from the deterministic case and a generally more conservative design is obtained with increasing risk aversion on the part of the designer.

  4. Cost-effectiveness of increasing the reach of smoking cessation interventions in Germany: results from the EQUIPTMOD.

    Science.gov (United States)

    Huber, Manuel B; Präger, Maximilian; Coyle, Kathryn; Coyle, Doug; Lester-George, Adam; Trapero-Bertran, Marta; Nemeth, Bertalan; Cheung, Kei Long; Stark, Renee; Vogl, Matthias; Pokhrel, Subhash; Leidl, Reiner

    2017-12-15

    To evaluate costs, effects and cost-effectiveness of increased reach of specific smoking cessation interventions in Germany. A Markov-based state transition return on investment model (EQUIPTMOD) was used to evaluate current smoking cessation interventions as well as two prospective investment scenarios. A health-care perspective (extended to include out-of-pocket payments) with life-time horizon was considered. A probabilistic analysis was used to assess uncertainty concerning predicted estimates. Germany. Cohort of current smoking population (18+ years) in Germany. Interventions included group-based behavioural support, financial incentive programmes and varenicline. For prospective scenario 1 the reach of group-based behavioral support, financial incentive programme and varenicline was increased by 1% of yearly quit attempts (= 57 915 quit attempts), while prospective scenario 2 represented a higher reach, mirroring the levels observed in England. EQUIPTMOD considered reach, intervention cost, number of quitters, quality-of-life years (QALYs) gained, cost-effectiveness and return on investment. The highest returns through reduction in smoking-related health-care costs were seen for the financial incentive programme (€2.71 per €1 invested), followed by that of group-based behavioural support (€1.63 per €1 invested), compared with no interventions. Varenicline had lower returns (€1.02 per €1 invested) than the other two interventions. At the population level, prospective scenario 1 led to 15 034 QALYs gained and €27 million cost-savings, compared with current investment. Intervention effects and reach contributed most to the uncertainty around the return-on-investment estimates. At a hypothetical willingness-to-pay threshold of only €5000, the probability of being cost-effective is approximately 75% for prospective scenario 1. Increasing the reach of group-based behavioural support, financial incentives and varenicline for smoking cessation by

  5. Issues and major steps in a conceptual framework for environmental costing

    International Nuclear Information System (INIS)

    DePape, D.; Kristjanson, E.R.; Onyebuchi, E.I.; Wojczynski, E.

    1992-01-01

    The concept of applying monetary values to environmental consequences as a means of integrating environmental considerations into utility resource planning is explored. The need for estimation and integration of environmental costs and benefits is becoming more important due to public concern over environmental degradation, rapidly increasing costs of mitigating environmental damage, increased liability for compensation for such damage, pressures to consider environmental externalities, and a corporate desire to operate responsibly. Manitoba Hydro established a task force to develop general approaches and specific techniques for evaluation and integration of environmental costs and benefits into utility planning. The utility's conceptual framework for monetizing and integrating environmental costs and benefits is described, including identification of potential environmental impacts, evaluation of environmental impacts, estimation of monetary and non-monetary costs and benefits, and integration of these costs and benefits into the resource planning process. Key issues that must be addressed to implement this conceptual framework include the need for earlier environmental impact assessments and the need for mitigation and compensation prediction methodologies. 1 fig., 1 tab

  6. Shale gas wastewater management under uncertainty.

    Science.gov (United States)

    Zhang, Xiaodong; Sun, Alexander Y; Duncan, Ian J

    2016-01-01

    This work presents an optimization framework for evaluating different wastewater treatment/disposal options for water management during hydraulic fracturing (HF) operations. This framework takes into account both cost-effectiveness and system uncertainty. HF has enabled rapid development of shale gas resources. However, wastewater management has been one of the most contentious and widely publicized issues in shale gas production. The flowback and produced water (known as FP water) generated by HF may pose a serious risk to the surrounding environment and public health because this wastewater usually contains many toxic chemicals and high levels of total dissolved solids (TDS). Various treatment/disposal options are available for FP water management, such as underground injection, hazardous wastewater treatment plants, and/or reuse. In order to cost-effectively plan FP water management practices, including allocating FP water to different options and planning treatment facility capacity expansion, an optimization model named UO-FPW is developed in this study. The UO-FPW model can handle the uncertain information expressed in the form of fuzzy membership functions and probability density functions in the modeling parameters. The UO-FPW model is applied to a representative hypothetical case study to demonstrate its applicability in practice. The modeling results reflect the tradeoffs between economic objective (i.e., minimizing total-system cost) and system reliability (i.e., risk of violating fuzzy and/or random constraints, and meeting FP water treatment/disposal requirements). Using the developed optimization model, decision makers can make and adjust appropriate FP water management strategies through refining the values of feasibility degrees for fuzzy constraints and the probability levels for random constraints if the solutions are not satisfactory. The optimization model can be easily integrated into decision support systems for shale oil/gas lifecycle

  7. Cost-effectiveness of 13-valent pneumococcal conjugate vaccination in Mongolia.

    Science.gov (United States)

    Sundaram, Neisha; Chen, Cynthia; Yoong, Joanne; Luvsan, Munkh-Erdene; Fox, Kimberley; Sarankhuu, Amarzaya; La Vincente, Sophie; Jit, Mark

    2017-02-15

    The Ministry of Health (MOH), Mongolia, is considering introducing 13-valent pneumococcal conjugate vaccine (PCV13) in its national immunization programme to prevent the burden of disease caused by Streptococcus pneumoniae. This study evaluates the cost-effectiveness and budget impact of introducing PCV13 compared to no PCV vaccination in Mongolia. The incremental cost-effectiveness ratio (ICER) of introducing PCV13 compared to no PCV vaccination was assessed using an age-stratified static multiple cohort model. The risk of various clinical presentations of pneumococcal disease (meningitis, pneumonia, non-meningitis non-pneumonia invasive pneumococcal disease and acute otitis media) at all ages for thirty birth cohorts was assessed. The analysis considered both health system and societal perspectives. A 3+0 vaccine schedule and price of US$3.30 per dose was assumed for the baseline scenario based on Gavi, the Vaccine Alliance's advance market commitment tail price. The ICER of PCV13 introduction is estimated at US$52 per disability-adjusted life year (DALY) averted (health system perspective), and cost-saving (societal perspective). Although indirect effects of PCV have been well-documented, a conservative scenario that does not consider indirect effects estimated PCV13 introduction to cost US$79 per DALY averted (health system perspective), and US$19 per DALY averted (societal perspective). Vaccination with PCV13 is expected to cost around US$920,000 in 2016, and thereafter US$820,000 every year. The programme is likely to reduce direct disease-related costs to MOH by US$440,000 in the first year, increasing to US$510,000 by 2025. Introducing PCV13 as part of Mongolia's national programme appears to be highly cost-effective when compared to no vaccination and cost-saving from a societal perspective at vaccine purchase prices offered through Gavi. Notwithstanding uncertainties around some parameters, cost-effectiveness of PCV introduction for Mongolia remains

  8. Probabilistic cost-benefit analysis of disaster risk management in a development context.

    Science.gov (United States)

    Kull, Daniel; Mechler, Reinhard; Hochrainer-Stigler, Stefan

    2013-07-01

    Limited studies have shown that disaster risk management (DRM) can be cost-efficient in a development context. Cost-benefit analysis (CBA) is an evaluation tool to analyse economic efficiency. This research introduces quantitative, stochastic CBA frameworks and applies them in case studies of flood and drought risk reduction in India and Pakistan, while also incorporating projected climate change impacts. DRM interventions are shown to be economically efficient, with integrated approaches more cost-effective and robust than singular interventions. The paper highlights that CBA can be a useful tool if certain issues are considered properly, including: complexities in estimating risk; data dependency of results; negative effects of interventions; and distributional aspects. The design and process of CBA must take into account specific objectives, available information, resources, and the perceptions and needs of stakeholders as transparently as possible. Intervention design and uncertainties should be qualified through dialogue, indicating that process is as important as numerical results. © 2013 The Author(s). Journal compilation © Overseas Development Institute, 2013.

  9. On the uncertainties in effective dose estimates of adult CT head scans

    International Nuclear Information System (INIS)

    Gregory, Kent J.; Bibbo, Giovanni; Pattison, John E.

    2008-01-01

    Estimates of the effective dose to adult patients from computed tomography (CT) head scanning can be calculated using a number of different methods. These estimates can be used for a variety of purposes, such as improving scanning protocols, comparing different CT imaging centers, and weighing the benefits of the scan against the risk of radiation-induced cancer. The question arises: What is the uncertainty in these effective dose estimates? This study calculates the uncertainty of effective dose estimates produced by three computer programs (CT-EXPO, CTDosimetry, and ImpactDose) and one method that makes use of dose-length product (DLP) values. Uncertainties were calculated in accordance with an internationally recognized uncertainty analysis guide. For each of the four methods, the smallest and largest overall uncertainties (stated at the 95% confidence interval) were: 20%-31% (CT-EXPO), 15%-28% (CTDosimetry), 20%-36% (ImpactDose), and 22%-32% (DLP), respectively. The overall uncertainties for each method vary due to differences in the uncertainties of factors used in each method. The smallest uncertainties apply when the CT dose index for the scanner has been measured using a calibrated pencil ionization chamber

  10. The Cost-Effectiveness of Dual Mobility Implants for Primary Total Hip Arthroplasty: A Computer-Based Cost-Utility Model.

    Science.gov (United States)

    Barlow, Brian T; McLawhorn, Alexander S; Westrich, Geoffrey H

    2017-05-03

    Dislocation remains a clinically important problem following primary total hip arthroplasty, and it is a common reason for revision total hip arthroplasty. Dual mobility (DM) implants decrease the risk of dislocation but can be more expensive than conventional implants and have idiosyncratic failure mechanisms. The purpose of this study was to investigate the cost-effectiveness of DM implants compared with conventional bearings for primary total hip arthroplasty. Markov model analysis was conducted from the societal perspective with use of direct and indirect costs. Costs, expressed in 2013 U.S. dollars, were derived from the literature, the National Inpatient Sample, and the Centers for Medicare & Medicaid Services. Effectiveness was expressed in quality-adjusted life years (QALYs). The model was populated with health state utilities and state transition probabilities derived from previously published literature. The analysis was performed for a patient's lifetime, and costs and effectiveness were discounted at 3% annually. The principal outcome was the incremental cost-effectiveness ratio (ICER), with a willingness-to-pay threshold of $100,000/QALY. Sensitivity analyses were performed to explore relevant uncertainty. In the base case, DM total hip arthroplasty showed absolute dominance over conventional total hip arthroplasty, with lower accrued costs ($39,008 versus $40,031 U.S. dollars) and higher accrued utility (13.18 versus 13.13 QALYs) indicating cost-savings. DM total hip arthroplasty ceased being cost-saving when its implant costs exceeded those of conventional total hip arthroplasty by $1,023, and the cost-effectiveness threshold for DM implants was $5,287 greater than that for conventional implants. DM was not cost-effective when the annualized incremental probability of revision from any unforeseen failure mechanism or mechanisms exceeded 0.29%. The probability of intraprosthetic dislocation exerted the most influence on model results. This model

  11. Wastewater treatment modelling: dealing with uncertainties

    DEFF Research Database (Denmark)

    Belia, E.; Amerlinck, Y.; Benedetti, L.

    2009-01-01

    This paper serves as a problem statement of the issues surrounding uncertainty in wastewater treatment modelling. The paper proposes a structure for identifying the sources of uncertainty introduced during each step of an engineering project concerned with model-based design or optimisation...

  12. Cost-effectiveness of a complex workplace dietary intervention: an economic evaluation of the Food Choice at Work study.

    Science.gov (United States)

    Fitzgerald, Sarah; Murphy, Aileen; Kirby, Ann; Geaney, Fiona; Perry, Ivan J

    2018-03-03

    To evaluate the costs, benefits and cost-effectiveness of complex workplace dietary interventions, involving nutrition education and system-level dietary modification, from the perspective of healthcare providers and employers. Single-study economic evaluation of a cluster-controlled trial (Food Choice at Work (FCW) study) with 1-year follow-up. Four multinational manufacturing workplaces in Cork, Ireland. 517 randomly selected employees (18-65 years) from four workplaces. Cost data were obtained from the FCW study. Nutrition education included individual nutrition consultations, nutrition information (traffic light menu labelling, posters, leaflets and emails) and presentations. System-level dietary modification included menu modification (restriction of fat, sugar and salt), increase in fibre, fruit discounts, strategic positioning of healthier alternatives and portion size control. The combined intervention included nutrition education and system-level dietary modification. No intervention was implemented in the control. The primary outcome was an improvement in health-related quality of life, measured using the EuroQoL 5 Dimensions 5 Levels questionnaire. The secondary outcome measure was reduction in absenteeism, which is measured in monetary amounts. Probabilistic sensitivity analysis (Monte Carlo simulation) assessed parameter uncertainty. The system-level intervention dominated the education and combined interventions. When compared with the control, the incremental cost-effectiveness ratio (€101.37/quality-adjusted life-year) is less than the nationally accepted ceiling ratio, so the system-level intervention can be considered cost-effective. The cost-effectiveness acceptability curve indicates there is some decision uncertainty surrounding this, arising from uncertainty surrounding the differences in effectiveness. These results are reiterated when the secondary outcome measure is considered in a cost-benefit analysis, whereby the system

  13. Generalized uncertainty principles, effective Newton constant and regular black holes

    OpenAIRE

    Li, Xiang; Ling, Yi; Shen, You-Gen; Liu, Cheng-Zhou; He, Hong-Sheng; Xu, Lan-Fang

    2016-01-01

    In this paper, we explore the quantum spacetimes that are potentially connected with the generalized uncertainty principles. By analyzing the gravity-induced quantum interference pattern and the Gedanken for weighting photon, we find that the generalized uncertainty principles inspire the effective Newton constant as same as our previous proposal. A characteristic momentum associated with the tidal effect is suggested, which incorporates the quantum effect with the geometric nature of gravity...

  14. Cost-Effectiveness Analysis of Regorafenib for Gastrointestinal Stromal Tumour (GIST) in Germany.

    Science.gov (United States)

    Tamoschus, David; Draexler, Katja; Chang, Jane; Ngai, Christopher; Madin-Warburton, Matthew; Pitcher, Ashley

    2017-06-01

    No study has compared the cost-effectiveness of active treatment options for unresectable or metastatic gastrointestinal stromal tumours in patients who progressed on or are intolerant to prior treatment with imatinib and sunitinib. The aim of this study was to estimate the cost-effectiveness of regorafenib compared to imatinib rechallenge in this setting in Germany. Hazard ratios for progression-free (PFS) and overall survival (OS) with regorafenib versus imatinib rechallenge were estimated by indirect comparison. A state distribution model was used to simulate progression, mortality and treatment costs over a lifetime horizon. Drug acquisition costs and utilities were derived from clinical trial data and published literature; non-drug costs were not included. The outcomes measured were treatment costs, life-years (LYs) and quality-adjusted life-years (QALYs). The indirect comparison suggested that median PFS and OS were longer with regorafenib compared to imatinib but results were not statistically significant. Regorafenib versus imatinib rechallenge was estimated to have hazard ratios of 0.58 (95% CI 0.31-1.11) for PFS and 0.77 (95% CI 0.34-1.77) for OS, with substantial uncertainty due to the rarity of the disease and small number of patients within the trials. Regorafenib treatment per patient over a lifetime horizon provided an additional 0.61 LYs and 0.42 QALYs over imatinib rechallenge, with additional direct drug costs of €8,773. The incremental cost-effectiveness ratio was €21,127 per QALY gained. At a cost-effectiveness threshold of €50,000 per QALY, regorafenib had a 67% probability of being cost-effective. Based on the currently available clinical data, this analysis suggests that regorafenib is cost-effective compared with imatinib rechallenge in Germany.

  15. A review on future trends of LWR fuel cycle costs

    International Nuclear Information System (INIS)

    Tamiya, S.; Otomo, T.; Meguro, T.

    1977-01-01

    In the cost estimations in the past, the main components of fuel cycle were mining and milling, uranium enrichment and fuel fabrication, and reprocessing charge deemed to be recovered by plutonium credit. Since the oil crisis, every component of fuel cycle cost has gone up in recent years as well as the construction cost of a power station. Recent analysis shows that the costs in the back end of fuel cycle are much higher than those anticipated several years ago, although their contribution to the electricity generating cost by nuclear would be small. The situation of the back end of the fuel cycle has been quite changed in recent years, and there are still many uncertainties in this field, that is, regulatory requirements for reprocessing plant such as safety, safeguards, environmental protection and high level waste management. So, it makes it more difficult to estimate the investment in this sector of fuel cycle, therefore, to estimate the cost of this sector. The institutional problems must be cleared in relation to the ultimate disposal of high level waste, too. Co-location of some parts of fuel cycle facilities may also affect on the fuel cycle costs. In this paper a review is made of the future trend of nuclear fuel cycle cost of LWR based on the recent analysis. Those factors which affect the fuel cycle costs are also discussed. In order to reduce the uncertainties of the cost estimations as soon as possible, the necessity is emphasized to discuss internationally such items as the treatment and disposal of high level radioactive wastes, siting issues of a reprocessing plant, physical protection of plutonium and the effects of plutonium on the environment

  16. Trastuzumab in early stage breast cancer: a cost-effectiveness analysis for Belgium.

    Science.gov (United States)

    Neyt, Mattias; Huybrechts, Michel; Hulstaert, Frank; Vrijens, France; Ramaekers, Dirk

    2008-08-01

    Although trastuzumab is traditionally used in metastatic breast cancer treatment, studies reported on the efficacy and safety of trastuzumab in adjuvant setting for the treatment of early stage breast cancer in HER2+ tumors. We estimated the cost-effectiveness and budget impact of reimbursing trastuzumab in this indication from a payer's perspective. We constructed a health economic model. Long-term consequences of preventing patients to progress to metastatic breast cancer and side effects such as congestive heart failure were taken into account. Uncertainty was handled applying probabilistic modeling and through probabilistic sensitivity analyses. In the HERA scenario, applying an arbitrary threshold of euro30000 per life-year gained, early stage breast cancer treatment with trastuzumab is cost-effective for 9 out of 15 analyzed subgroups (according to age and stage). In contrast, treatment according to the FinHer scenario is cost-effective in 14 subgroups. Furthermore, the FinHer regimen is most of the times cost saving with an average incremental cost of euro668, euro-1045, and euro-6869 for respectively stages I, II and III breast cancer patients whereas the HERA regimen is never cost saving due to the higher initial treatment costs. The model shows better cost-effectiveness for the 9-week initial treatment (FinHer) compared to no trastuzumab treatment than for the 1-year post-chemotherapy treatment (HERA). Both from a medical and an economic point of view, the 9-week initial treatment regimen with trastuzumab shows promising results and justifies the initiation of a large comparative trial with a 1-year regimen.

  17. Economic evaluation of private power production under uncertainties

    Energy Technology Data Exchange (ETDEWEB)

    Weiguo Xing; Wu, F.F. [University of Hong Kong (China). Centre for Electrical Energy Systems

    2003-02-01

    Private power production is becoming an increasingly important source of electricity generation. In developing countries, build-operate-transfer (BOT) arrangement has emerged as a dominant form of private investment. Pricing private power production at its avoided cost is the breakeven point for the utility in economic evaluation, and uncertainties must be taken into account. In this paper, an approach of calculating the breakeven cost to the utility of a BOT power plant whose contract lasts for 10-25 years is proposed. The proposed approach requires the computation of production costs from long-term generation expansion planning (GEP) under future uncertainties. To facilitate the inclusion of constraints introduced by BOT plants in GEP and uncertainties, a genetic algorithm method is utilized in GEP. The breakeven cost is a useful measure in the economic evaluation of BOT power plants. An example is presented to illustrate the economic evaluation of BOT plants using the concept of breakeven cost.(author)

  18. Cost-effectiveness analysis of salt reduction policies to reduce coronary heart disease in Syria, 2010-2020.

    Science.gov (United States)

    Wilcox, Meredith L; Mason, Helen; Fouad, Fouad M; Rastam, Samer; al Ali, Radwan; Page, Timothy F; Capewell, Simon; O'Flaherty, Martin; Maziak, Wasim

    2015-01-01

    This study presents a cost-effectiveness analysis of salt reduction policies to lower coronary heart disease in Syria. Costs and benefits of a health promotion campaign about salt reduction (HP); labeling of salt content on packaged foods (L); reformulation of salt content within packaged foods (R); and combinations of the three were estimated over a 10-year time frame. Policies were deemed cost-effective if their cost-effectiveness ratios were below the region's established threshold of $38,997 purchasing power parity (PPP). Sensitivity analysis was conducted to account for the uncertainty in the reduction of salt intake. HP, L, and R+HP+L were cost-saving using the best estimates. The remaining policies were cost-effective (CERs: R=$5,453 PPP/LYG; R+HP=$2,201 PPP/LYG; R+L=$2,125 PPP/LYG). R+HP+L provided the largest benefit with net savings using the best and maximum estimates, while R+L was cost-effective with the lowest marginal cost using the minimum estimates. This study demonstrated that all policies were cost-saving or cost effective, with the combination of reformulation plus labeling and a comprehensive policy involving all three approaches being the most promising salt reduction strategies to reduce CHD mortality in Syria.

  19. Monte Carlo approaches for uncertainty quantification of criticality for system dimensions

    International Nuclear Information System (INIS)

    Kiedrowski, B.C.; Brown, F.B.

    2013-01-01

    One of the current challenges in nuclear engineering computations is the issue of performing uncertainty analysis for either calculations or experimental measurements. This paper specifically focuses on the issue of estimating the uncertainties arising from geometric tolerances. For this paper, two techniques for uncertainty quantification are studied. The first is the forward propagation technique, which can be thought of as a 'brute force' approach; uncertain system parameters are randomly sampled, the calculation is run, and uncertainties are found from the empirically obtained distribution of results. This approach need make no approximations in principle, but is very computationally expensive. The other approach investigated is the adjoint-based approach; system sensitivities are computed via a single Monte Carlo calculation and those are used with a covariance matrix to provide a linear estimate of the uncertainty. Demonstration calculations are performed with the MCNP6 code for both techniques. The 2 techniques are tested on 2 cases: the first case is a solid, bare cylinder of Pu-metal while the second case is a can of plutonium nitrate solution. The results show that the forward and adjoint approaches appear to agree in some cases where the responses are not non-linearly correlated. In other cases, the uncertainties in the effective multiplication k disagree for reasons not yet known

  20. Controversies Regarding Costs, Uncertainties and Benefits Specific to Shale Gas Development

    Directory of Open Access Journals (Sweden)

    Jianu Daniel Muresan

    2015-03-01

    Full Text Available The shale gas exploration and development is now a delicate and controversial subject. It is often assumed that unconventional exploration and extraction automatically brings prosperity for local, national and regional economies. In this paper, we argue that shale gas development requires a contextualized understanding of regional issues. We are also trying to identify the opportunities and the risks of shale gas development in Eastern Europe (referring to Romania’s case and offer a cost-benefit analysis model that may be of interest to any policymakers and investors.

  1. Uncertainty as Information: Narrowing the Science-policy Gap

    Directory of Open Access Journals (Sweden)

    G. A. Bradshaw

    2000-07-01

    Full Text Available Conflict and indecision are hallmarks of environmental policy formulation. Some argue that the requisite information and certainty fall short of scientific standards for decision making; others argue that science is not the issue and that indecisiveness reflects a lack of political willpower. One of the most difficult aspects of translating science into policy is scientific uncertainty. Whereas scientists are familiar with uncertainty and complexity, the public and policy makers often seek certainty and deterministic solutions. We assert that environmental policy is most effective if scientific uncertainty is incorporated into a rigorous decision-theoretic framework as knowledge, not ignorance. The policies that best utilize scientific findings are defined here as those that accommodate the full scope of scientifically based predictions.

  2. Maximizing probable oil field profit: uncertainties on well spacing

    International Nuclear Information System (INIS)

    MacKay, J.A.; Lerche, I.

    1997-01-01

    The influence of uncertainties in field development costs, well costs, lifting costs, selling price, discount factor, and oil field reserves are evaluated for their impact on assessing probable ranges of uncertainty on present day worth (PDW), oil field lifetime τ 2/3 , optimum number of wells (OWI), and the minimum (n-) and maximum (n+) number of wells to produce a PDW ≥ O. The relative importance of different factors in contributing to the uncertainties in PDW, τ 2/3 , OWI, nsub(-) and nsub(+) is also analyzed. Numerical illustrations indicate how the maximum PDW depends on the ranges of parameter values, drawn from probability distributions using Monte Carlo simulations. In addition, the procedure illustrates the relative importance of contributions of individual factors to the total uncertainty, so that one can assess where to place effort to improve ranges of uncertainty; while the volatility of each estimate allows one to determine when such effort is needful. (author)

  3. Probabilistic Mass Growth Uncertainties

    Science.gov (United States)

    Plumer, Eric; Elliott, Darren

    2013-01-01

    Mass has been widely used as a variable input parameter for Cost Estimating Relationships (CER) for space systems. As these space systems progress from early concept studies and drawing boards to the launch pad, their masses tend to grow substantially, hence adversely affecting a primary input to most modeling CERs. Modeling and predicting mass uncertainty, based on historical and analogous data, is therefore critical and is an integral part of modeling cost risk. This paper presents the results of a NASA on-going effort to publish mass growth datasheet for adjusting single-point Technical Baseline Estimates (TBE) of masses of space instruments as well as spacecraft, for both earth orbiting and deep space missions at various stages of a project's lifecycle. This paper will also discusses the long term strategy of NASA Headquarters in publishing similar results, using a variety of cost driving metrics, on an annual basis. This paper provides quantitative results that show decreasing mass growth uncertainties as mass estimate maturity increases. This paper's analysis is based on historical data obtained from the NASA Cost Analysis Data Requirements (CADRe) database.

  4. Cost-Effectiveness of Bronchial Thermoplasty, Omalizumab, and Standard Therapy for Moderate-to-Severe Allergic Asthma.

    Science.gov (United States)

    Zafari, Zafar; Sadatsafavi, Mohsen; Marra, Carlo A; Chen, Wenjia; FitzGerald, J Mark

    2016-01-01

    Bronchial thermoplasty (BT) is a recently developed treatment for patients with moderate-to-severe asthma. A few studies have suggested the clinical efficacy of this intervention. However, no study has evaluated the cost-effectiveness of BT compared to other alternative treatments for moderate-to-severe allergic asthma, which currently include omalizumab and standard therapy. To evaluate the cost-effectiveness of standard therapy, BT, and omalizumab for moderate-to-severe allergic asthma in the USA. A probabilistic Markov model with weekly cycles was developed to reflect the course of asthma progression over a 5-year time horizon. The study population was adults with moderate-to-severe allergic asthma whose asthma remained uncontrolled despite using high-dose inhaled corticosteroids (ICS, with or without long-acting beta-agonists [LABA]). A perspective of the health-care system was adopted with asthma-related costs as well as quality-adjusted life years (QALYs) and exacerbations as the outcomes. For standard therapy, BT, and omalizumab, the discounted 5-year costs and QALYs were $15,400 and 3.08, $28,100 and 3.24, and $117,000 and 3.26, respectively. The incremental cost-effectiveness ratio (ICER) of BT versus standard therapy and omalizumab versus BT was $78,700/QALY and $3.86 million/QALY, respectively. At the willingness-to-pay (WTP) of $50,000/QALY and $100,000/QALY, the probability of BT being cost-effective was 9%, and 67%, respectively. The corresponding expected value of perfect information (EVPI) was $155 and $1,530 per individual at these thresholds. In sensitivity analyses, increasing the costs of BT from $14,900 to $30,000 increased its ICER relative to standard therapy to $178,000/QALY, and decreased the ICER of omalizumab relative to BT to $3.06 million/QALY. Reducing the costs of omalizumab by 25% decreased its ICER relative to BT by 29%. Based on the available evidence, our study suggests that there is more than 60% chance that BT becomes cost-effective

  5. Cost-Effectiveness of Bronchial Thermoplasty, Omalizumab, and Standard Therapy for Moderate-to-Severe Allergic Asthma.

    Directory of Open Access Journals (Sweden)

    Zafar Zafari

    cost-effective relative to omalizumab and standard therapy at the WTP of $100,000/QALY in patients with moderate-to-severe allergic asthma. However, there is a substantial uncertainty in the underlying evidence, indicating the need for future research towards reducing such uncertainty.

  6. Estimating the costs of nuclear power: benchmarks and uncertainties

    International Nuclear Information System (INIS)

    Leveque, Francois

    2013-05-01

    The debate on this topic is fairly confusing. Some present electricity production using nuclear power as an affordable solution, others maintain it is too expensive. These widely divergent views prompt fears among consumers and voters that they are being manipulated: each side is just defending its own interests and the true cost of nuclear power is being concealed. Companies and non-government organizations certainly adopt whatever position suits them best. But at the same time, the notion of just one 'true' cost is misleading. As we shall see in this paper there is no such thing as the cost of nuclear power: we must reason in terms of costs and draw a distinction between a private cost and a social cost. The private cost is what an operator examines before deciding whether it is opportune to build a new nuclear power station. This cost varies between different investors, particularly as a function of their attitude to risks. On the other hand the social cost weighs on society, which may take into account the risk of proliferation, or the benefits of avoiding carbon-dioxide emissions, among others. The cost of actually building new plant differs from one country to the next. So deciding whether nuclear power is profitable or not, a benefit for society or not, does not involve determining the real cost, but rather compiling data, developing methods and formulating hypotheses. It is not as easy as inundating the general public with contradictory figures, but it is a more effective way of casting light on economic decisions by industry and government. Without evaluating the costs it is impossible to establish the cost price, required to compare electricity production using nuclear power and rival technologies. Would it be preferable to build a gas-powered plant, a nuclear reactor or a wind farm? Which technology yields the lowest cost per KWh? Under what conditions - financial terms, regulatory framework, carbon pricing - will private investors see an adequate return

  7. A prioritization of generic safety issues. Supplement 21, Revision insertion instructions

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    1996-12-31

    The report presents the safety priority ranking for generic safety issues related to nuclear power plants. The purpose of these rankings is to assist in the timely and efficient allocation of NRC resources for the resolution of those safety issues that have a significant potential for reducing risk. The safety priority rankings are HIGH, MEDIUM, LOW, and DROP, and have been assigned on the basis of risk significance estimates, the ratio of risk to costs and other impacts estimated to result if resolution of the safety issues were implemented, and the consideration of uncertainties and other quantitative or qualitative factors. To the extent practical, estimates are quantitative.

  8. A prioritization of generic safety issues. Supplement 21, Revision insertion instructions

    International Nuclear Information System (INIS)

    1996-01-01

    The report presents the safety priority ranking for generic safety issues related to nuclear power plants. The purpose of these rankings is to assist in the timely and efficient allocation of NRC resources for the resolution of those safety issues that have a significant potential for reducing risk. The safety priority rankings are HIGH, MEDIUM, LOW, and DROP, and have been assigned on the basis of risk significance estimates, the ratio of risk to costs and other impacts estimated to result if resolution of the safety issues were implemented, and the consideration of uncertainties and other quantitative or qualitative factors. To the extent practical, estimates are quantitative.

  9. Assessing ecological effects of radionuclides: data gaps and extrapolation issues

    International Nuclear Information System (INIS)

    Garnier-Laplace, Jacqueline; Gilek, Michael; Sundell-Bergman, Synnoeve; Larsson, Carl-Magnus

    2004-01-01

    By inspection of the FASSET database on radiation effects on non-human biota, one of the major difficulties in the implementation of ecological risk assessments for radioactive pollutants is found to be the lack of data for chronic low-level exposure. A critical review is provided of a number of extrapolation issues that arise in undertaking an ecological risk assessment: acute versus chronic exposure regime; radiation quality including relative biological effectiveness and radiation weighting factors; biological effects from an individual to a population level, including radiosensitivity and lifestyle variations throughout the life cycle; single radionuclide versus multi-contaminants. The specificities of the environmental situations of interest (mainly chronic low-level exposure regimes) emphasise the importance of reproductive parameters governing the demography of the population within a given ecosystem and, as a consequence, the structure and functioning of that ecosystem. As an operational conclusion to keep in mind for any site-specific risk assessment, the present state-of-the-art on extrapolation issues allows us to grade the magnitude of the uncertainties as follows: one species to another > acute to chronic = external to internal = mixture of stressors> individual to population> ecosystem structure to function

  10. Can Economic Model Transparency Improve Provider Interpretation of Cost-effectiveness Analysis? Evaluating Tradeoffs Presented by the Second Panel on Cost-effectiveness in Health and Medicine.

    Science.gov (United States)

    Padula, William V; McQueen, Robert Brett; Pronovost, Peter J

    2017-11-01

    The Second Panel on Cost-Effectiveness in Health and Medicine convened on December 7, 2016 at the National Academy of Medicine to disseminate their recommendations for conduct, methodological practices, and reporting of cost-effectiveness analyses (CEAs). Following its summary, panel proceedings included lengthy discussions including the field's struggle to disseminate findings efficiently through peer-reviewed literature to target audiences. With editors of several medical and outcomes research journals in attendance, there was consensus that findings of cost-effectiveness analyses do not effectively reach other researchers or health care providers. The audience members suggested several solutions including providing additional training to clinicians in cost-effectiveness research and requiring that cost-effectiveness models are made publicly available. However, there remains the questions of whether making economic modelers' work open-access through journals is fair under the defense that these models remain one's own intellectual property, or whether journals can properly manage the peer-review process specifically for cost-effectiveness analyses. In this article, we elaborate on these issues and provide some suggested solutions that may increase the dissemination and application of cost-effectiveness literature to reach its intended audiences and ultimately benefit the patient. Ultimately, it is our combined view as economic modelers and clinicians that cost-effectiveness results need to reach the clinician to improve the efficiency of medical practice, but that open-access models do not improve clinician access or interpretation of the economics of medicine.

  11. Engineering and Fabrication Considerations for Cost-Effective Space Reactor Shield Development

    International Nuclear Information System (INIS)

    Berg, Thomas A.; Disney, Richard K.

    2004-01-01

    Investment in developing nuclear power for space missions cannot be made on the basis of a single mission. Current efforts in the design and fabrication of the reactor module, including the reactor shield, must be cost-effective and take into account scalability and fabricability for planned and future missions. Engineering considerations for the shield need to accommodate passive thermal management, varying radiation levels and effects, and structural/mechanical issues. Considering these challenges, design principles and cost drivers specific to the engineering and fabrication of the reactor shield are presented that contribute to lower recurring mission costs

  12. Establishing a cost model when estimating product cost in early design phases

    OpenAIRE

    Jeppsson, Johanna; Sjöberg, Jessica

    2017-01-01

    About 75% of the total product cost is determined in the early design phase, which means that the possibilities to affect costs are relatively small when the design phase is completed. For companies, it is therefore vital to conduct reliable cost estimates in the early design phase, when selecting between different design choices. When conducting a cost estimate there are many uncertainties. The aim with this study is therefore to explore how uncertainties regarding product cost can be consid...

  13. Analysis and Reduction of Complex Networks Under Uncertainty

    Energy Technology Data Exchange (ETDEWEB)

    Knio, Omar M

    2014-04-09

    This is a collaborative proposal that aims at developing new methods for the analysis and reduction of complex multiscale networks under uncertainty. The approach is based on combining methods of computational singular perturbation (CSP) and probabilistic uncertainty quantification. In deterministic settings, CSP yields asymptotic approximations of reduced-dimensionality “slow manifolds” on which a multiscale dynamical system evolves. Introducing uncertainty raises fundamentally new issues, particularly concerning its impact on the topology of slow manifolds, and means to represent and quantify associated variability. To address these challenges, this project uses polynomial chaos (PC) methods to reformulate uncertain network models, and to analyze them using CSP in probabilistic terms. Specific objectives include (1) developing effective algorithms that can be used to illuminate fundamental and unexplored connections among model reduction, multiscale behavior, and uncertainty, and (2) demonstrating the performance of these algorithms through applications to model problems.

  14. Preventing postnatal maternal mental health problems using a psychoeducational intervention: the cost-effectiveness of What Were We Thinking.

    Science.gov (United States)

    Ride, Jemimah; Lorgelly, Paula; Tran, Thach; Wynter, Karen; Rowe, Heather; Fisher, Jane

    2016-11-18

    Postnatal maternal mental health problems, including depression and anxiety, entail a significant burden globally, and finding cost-effective preventive solutions is a public policy priority. This paper presents a cost-effectiveness analysis of the intervention, What Were We Thinking (WWWT), for the prevention of postnatal maternal mental health problems. The economic evaluation, including cost-effectiveness and cost-utility analyses, was conducted alongside a cluster-randomised trial. 48 Maternal and Child Health Centres in Victoria, Australia. Participants were English-speaking first-time mothers attending participating Maternal and Child Health Centres. Full data were collected for 175 participants in the control arm and 184 in the intervention arm. WWWT is a psychoeducational intervention targeted at the partner relationship, management of infant behaviour and parental fatigue. The evaluation considered public sector plus participant out-of-pocket costs, while outcomes were expressed in the 30-day prevalence of depression, anxiety and adjustment disorders, and quality-adjusted life years (QALYs). Incremental costs and outcomes were estimated using regression analyses to account for relevant sociodemographic, prognostic and clinical characteristics. The intervention was estimated to cost $A118.16 per participant. The analysis showed no statistically significant difference between the intervention and control groups in costs or outcomes. The incremental cost-effectiveness ratios were $A36 451 per QALY gained and $A152 per percentage-point reduction in 30-day prevalence of depression, anxiety and adjustment disorders. The estimate lies under the unofficial cost-effectiveness threshold of $A55 000 per QALY; however, there was considerable uncertainty surrounding the results, with a 55% probability that WWWT would be considered cost-effective at that threshold. The results suggest that, although WWWT shows promise as a preventive intervention for postnatal

  15. Modeling the effects of uncertainty on fear of nuclear waste: Differences among science, business and environmental group members

    Energy Technology Data Exchange (ETDEWEB)

    Bassett, G. [Illinois Univ., Chicago, IL (United States). Dept. of Economics]|[Argonne National Lab., IL (United States); Jenkins-Smith, H. [New Mexico Univ., Albuquerque, NM (United States). Dept. of Political Science]|[Argonne National Lab., IL (United States)

    1992-10-01

    This paper analyzes the relationships between the subjective assessment of riskiness of managing nuclear waste and the level of certainty regarding the assessment. Uncertainty can be operationalized in two ways. The direct approach asks a person to assess their own subjective beliefs about a potential hazard. The indirect approach assesses how readily an individual will change his or her beliefs when confronted with new information that conflicts with prior beliefs. This paper tests for the relationships between these two distinct operationalizations of uncertainty and overall assessments of the risks posed by radioactive wastes. First we analyze the relationships between stated levels of uncertainty about the effects of radiation on the level of perceived risks from radioactive wastes. Second, we assess the linkage between willingness to alter prior beliefs about the risks of radioactive wastes in response to new information provided by ``a neutral source`` (or responsiveness of beliefs) and uncertainty. Using data taken from random mail surveys of members of scientific, business, and environmental groups in Colorado and New Mexico in the summer of 1990, we test hypotheses that (a) greater uncertainty is associated with greater perceived risks, and (b) greater responsiveness of beliefs to new information is associated with greater uncertainty. The import of these hypotheses concerns the dynamics of uncertainty in controversial technical policy issues, wherein perceived risks are a primary ingredient in policy positions taken by participants in policy disputes.

  16. Modeling the effects of uncertainty on fear of nuclear waste: Differences among science, business and environmental group members

    Energy Technology Data Exchange (ETDEWEB)

    Bassett, G. (Illinois Univ., Chicago, IL (United States). Dept. of Economics Argonne National Lab., IL (United States)); Jenkins-Smith, H. (New Mexico Univ., Albuquerque, NM (United States). Dept. of Political Science Argonne National Lab., IL (United States))

    1992-10-01

    This paper analyzes the relationships between the subjective assessment of riskiness of managing nuclear waste and the level of certainty regarding the assessment. Uncertainty can be operationalized in two ways. The direct approach asks a person to assess their own subjective beliefs about a potential hazard. The indirect approach assesses how readily an individual will change his or her beliefs when confronted with new information that conflicts with prior beliefs. This paper tests for the relationships between these two distinct operationalizations of uncertainty and overall assessments of the risks posed by radioactive wastes. First we analyze the relationships between stated levels of uncertainty about the effects of radiation on the level of perceived risks from radioactive wastes. Second, we assess the linkage between willingness to alter prior beliefs about the risks of radioactive wastes in response to new information provided by a neutral source'' (or responsiveness of beliefs) and uncertainty. Using data taken from random mail surveys of members of scientific, business, and environmental groups in Colorado and New Mexico in the summer of 1990, we test hypotheses that (a) greater uncertainty is associated with greater perceived risks, and (b) greater responsiveness of beliefs to new information is associated with greater uncertainty. The import of these hypotheses concerns the dynamics of uncertainty in controversial technical policy issues, wherein perceived risks are a primary ingredient in policy positions taken by participants in policy disputes.

  17. Modeling the effects of uncertainty on fear of nuclear waste: Differences among science, business and environmental group members

    International Nuclear Information System (INIS)

    Bassett, G.; Jenkins-Smith, H.

    1992-10-01

    This paper analyzes the relationships between the subjective assessment of riskiness of managing nuclear waste and the level of certainty regarding the assessment. Uncertainty can be operationalized in two ways. The direct approach asks a person to assess their own subjective beliefs about a potential hazard. The indirect approach assesses how readily an individual will change his or her beliefs when confronted with new information that conflicts with prior beliefs. This paper tests for the relationships between these two distinct operationalizations of uncertainty and overall assessments of the risks posed by radioactive wastes. First we analyze the relationships between stated levels of uncertainty about the effects of radiation on the level of perceived risks from radioactive wastes. Second, we assess the linkage between willingness to alter prior beliefs about the risks of radioactive wastes in response to new information provided by ''a neutral source'' (or responsiveness of beliefs) and uncertainty. Using data taken from random mail surveys of members of scientific, business, and environmental groups in Colorado and New Mexico in the summer of 1990, we test hypotheses that (a) greater uncertainty is associated with greater perceived risks, and (b) greater responsiveness of beliefs to new information is associated with greater uncertainty. The import of these hypotheses concerns the dynamics of uncertainty in controversial technical policy issues, wherein perceived risks are a primary ingredient in policy positions taken by participants in policy disputes

  18. Comment 2 on workshop in economics - issues in benefit-cost analysis: Amplification channels and discounting long-term environmental damages

    International Nuclear Information System (INIS)

    Hanson, D.A.

    1992-01-01

    Many environmental problems have long-term effects. Acid rain has long-term effects on soils, forests, and exposed materials. Global climate change has even longer-term effects. This difference in timing - between the near-term cost of environmental protection and the long-term environmental effects - makes it difficult to conduct a cost-benefit analysis of any program designed to abate environmental damages. The rate at which to discount long-term environmental damages becomes a key question in comparisons of benefits and costs. This comment points out an important facet of the discounting issue. The discount rate for calculating the present value of future environmental benefits may be much lower than the rate of return on investment. Cost-benefit analysis is a framework in which to evaluate policies and decisions. Because global climate change is a complex problem, extensions of cost-benefit theory can be expected to add additional insights, particularly in the following areas: distinguishing distributional effects among nations, over time, and among generations; determining the rate of discount that is appropriate for long-term environmental damages and separating risk aspects from the rate of discount; and assessing amplification effects when policies involve large expenditures relative to the economy or when affected sectors are significant sectors of the economy

  19. Nordic reference study on uncertainty and sensitivity analysis

    International Nuclear Information System (INIS)

    Hirschberg, S.; Jacobsson, P.; Pulkkinen, U.; Porn, K.

    1989-01-01

    This paper provides a review of the first phase of Nordic reference study on uncertainty and sensitivity analysis. The main objective of this study is to use experiences form previous Nordic Benchmark Exercises and reference studies concerning critical modeling issues such as common cause failures and human interactions, and to demonstrate the impact of associated uncertainties on the uncertainty of the investigated accident sequence. This has been done independently by three working groups which used different approaches to modeling and to uncertainty analysis. The estimated uncertainty interval for the analyzed accident sequence is large. Also the discrepancies between the groups are substantial but can be explained. Sensitivity analyses which have been carried out concern e.g. use of different CCF-quantification models, alternative handling of CCF-data, time windows for operator actions and time dependences in phase mission operation, impact of state-of-knowledge dependences and ranking of dominating uncertainty contributors. Specific findings with respect to these issues are summarized in the paper

  20. The Kyoto Protocol Is Cost-effective

    Directory of Open Access Journals (Sweden)

    Marino Gatto

    2002-06-01

    Full Text Available Despite recent advances, there is a high degree of uncertainty concerning the climate change that would result from increasing atmospheric greenhouse gas concentrations. Also, opponents of the Kyoto Protocol raised the key objection that reducing emissions would impose an unacceptable economic burden on businesses and consumers. Based on an analysis of alternative scenarios for electricity generation in Italy, we show that if the costs in terms of damage to human health, material goods, agriculture, and the environment caused by greenhouse gas emissions are included in the balance, the economic argument against Kyoto is untenable. Most importantly, the argument holds true even if we exclude global external costs (those due to global warming, and account for local external costs only (such as those due to acidic precipitation and lung diseases resulting from air pollution.

  1. Estimating and understanding DOE waste management costs'

    International Nuclear Information System (INIS)

    Kang, J.S.; Sherick, M.J.

    1995-01-01

    This paper examines costs associated with cleaning up the US Department of Energy's (DOE's) nuclear facilities, with particular emphasis on the waste management program. Life-cycle waste management costs have been compiled and reported in the DOE Baseline Environmental Management Report (BEMR). Waste management costs are a critical issue for DOE because of the current budget constraints. The DOE sites are struggling to accomplish their environmental management objectives given funding scenarios that are well below anticipated waste management costs. Through the BEMR process, DOE has compiled complex-wide cleanup cost estimates and has begun analysis of these costs with respect to alternative waste management scenarios and policy strategies. From this analysis, DOE is attempting to identify the major cost drivers and prioritize environmental management activities to achieve maximum utilization of existing funding. This paper provides an overview of the methodology DOE has used to estimate and analyze some waste management costs, including the key data requirements and uncertainties

  2. A critical evaluation of deterministic methods in size optimisation of reliable and cost effective standalone hybrid renewable energy systems

    International Nuclear Information System (INIS)

    Maheri, Alireza

    2014-01-01

    Reliability of a hybrid renewable energy system (HRES) strongly depends on various uncertainties affecting the amount of power produced by the system. In the design of systems subject to uncertainties, both deterministic and nondeterministic design approaches can be adopted. In a deterministic design approach, the designer considers the presence of uncertainties and incorporates them indirectly into the design by applying safety factors. It is assumed that, by employing suitable safety factors and considering worst-case-scenarios, reliable systems can be designed. In fact, the multi-objective optimisation problem with two objectives of reliability and cost is reduced to a single-objective optimisation problem with the objective of cost only. In this paper the competence of deterministic design methods in size optimisation of reliable standalone wind–PV–battery, wind–PV–diesel and wind–PV–battery–diesel configurations is examined. For each configuration, first, using different values of safety factors, the optimal size of the system components which minimises the system cost is found deterministically. Then, for each case, using a Monte Carlo simulation, the effect of safety factors on the reliability and the cost are investigated. In performing reliability analysis, several reliability measures, namely, unmet load, blackout durations (total, maximum and average) and mean time between failures are considered. It is shown that the traditional methods of considering the effect of uncertainties in deterministic designs such as design for an autonomy period and employing safety factors have either little or unpredictable impact on the actual reliability of the designed wind–PV–battery configuration. In the case of wind–PV–diesel and wind–PV–battery–diesel configurations it is shown that, while using a high-enough margin of safety in sizing diesel generator leads to reliable systems, the optimum value for this margin of safety leading to a

  3. Cost-effectiveness modeling for neuropathic pain treatments: investigating the relative importance of parameters using an open-source model.

    Science.gov (United States)

    Hirst, Matthew; Bending, Matthew W; Baio, Gianluca; Yesufu-Udechuku, Amina; Dunlop, William C N

    2018-06-08

    The study objective was to develop an open-source replicate of a cost-effectiveness model developed by National Institute for Health and Care (NICE) in order to explore uncertainties in health economic modeling of novel pharmacological neuropathic pain treatments. The NICE model, consisting of a decision tree with branches for discrete levels of pain relief and adverse event (AE) severities, was replicated using R and used to compare a hypothetical neuropathic pain drug to pregabalin. Model parameters were sourced from NICE's clinical guidelines and associated with probability distributions to account for underlying uncertainty. A simulation-based scenario analysis was conducted to assess how uncertainty in efficacy and AEs affected the net monetary benefit (NMB) for the hypothetical treatment at a cost-effectiveness threshold of £20,000 per QALY. Relative to pregabalin, an increase in efficacy was associated with greater NMB than an improvement in tolerability. A greater NMB was observed when efficacy was marginally higher than that of pregabalin while maintaining the same level of AEs than when efficacy was equivalent to pregabalin but with a more substantial reduction in AEs. In the latter scenario, the NMB was only positive at a low cost-effectiveness threshold. The replicate model shares the limitations described in the NICE guidelines. There is a lack of support in scientific literature for the assumption that increased efficacy is associated with a greater reduction in tolerability. The replicate model also included a single comparator, unlike the NICE model. Pain relief is a stronger driver of NMB than tolerability at a cost-effectiveness threshold of £20,000 per QALY. Health technology assessment decisions which are influenced by NICE's model may reward efficacy gains even if they are associated with more severe AEs. This contrasts with recommendations from clinical guidelines for neuropathic pain which place more equal weighting on improvements in

  4. A genetic-algorithm-aided stochastic optimization model for regional air quality management under uncertainty.

    Science.gov (United States)

    Qin, Xiaosheng; Huang, Guohe; Liu, Lei

    2010-01-01

    A genetic-algorithm-aided stochastic optimization (GASO) model was developed in this study for supporting regional air quality management under uncertainty. The model incorporated genetic algorithm (GA) and Monte Carlo simulation techniques into a general stochastic chance-constrained programming (CCP) framework and allowed uncertainties in simulation and optimization model parameters to be considered explicitly in the design of least-cost strategies. GA was used to seek the optimal solution of the management model by progressively evaluating the performances of individual solutions. Monte Carlo simulation was used to check the feasibility of each solution. A management problem in terms of regional air pollution control was studied to demonstrate the applicability of the proposed method. Results of the case study indicated the proposed model could effectively communicate uncertainties into the optimization process and generate solutions that contained a spectrum of potential air pollutant treatment options with risk and cost information. Decision alternatives could be obtained by analyzing tradeoffs between the overall pollutant treatment cost and the system-failure risk due to inherent uncertainties.

  5. Combining Time-Driven Activity-Based Costing with Clinical Outcome in Cost-Effectiveness Analysis to Measure Value in Treatment of Depression.

    Science.gov (United States)

    El Alaoui, Samir; Lindefors, Nils

    2016-01-01

    A major challenge of mental health care is to provide safe and effective treatment with limited resources. The main purpose of this study was to examine a value-based approach in clinical psychiatry when evaluating a process improvement initiative. This was accomplished by using the relatively new time driven activity based costing (TDABC) method within the more widely adopted cost-effectiveness analysis framework for economic evaluation of healthcare technologies. The objective was to evaluate the cost-effectiveness of allowing psychologists to perform post-treatment assessment previously performed by psychiatrists at an outpatient clinic treating depression using internet-based cognitive-behavioral therapy (ICBT). Data was collected from 568 adult patients treated with ICBT for depression during 2013-2014. The TDABC methodology was used to estimate total healthcare costs, including development of process maps for the complete cycle of care and estimation of resource use and minute costs of staff, hospital space and materials based on their relative proportions used. Clinical outcomes were measured using the Patient Health Questionnaire depression scale (PHQ-9) before and after treatment and at 6-month follow-up. Cost-effectiveness analyses (CEA) was performed and the results presented as incremental net benefits (INB), cost-effectiveness acceptability curves (CEACs) and confidence ellipses to demonstrate uncertainty around the value of the organizational intervention. Taking into account the complete healthcare process (from referral to follow-up assessment), treatment costs decreased from $709 (SD = $130) per patient in 2013 to $659 (SD = $134) in 2014 while treatment effectiveness was maintained; 27% had achieved full remission from depression after treatment (PHQ-9 cost-effectiveness plane at both post-treatment and at follow-up, indicating that the ICBT treatment was less costly and equally effective after staff reallocation. Treating patients to the target

  6. An uncertainty analysis using the NRPB accident consequence code Marc

    International Nuclear Information System (INIS)

    Jones, J.A.; Crick, M.J.; Simmonds, J.R.

    1991-01-01

    This paper describes an uncertainty analysis of MARC calculations of the consequences of accidental releases of radioactive materials to atmosphere. A total of 98 parameters describing the transfer of material through the environment to man, the doses received, and the health effects resulting from these doses, was considered. The uncertainties in the numbers of early and late health effects, numbers of people affected by countermeasures, the amounts of food restricted and the economic costs of the accident were estimated. This paper concentrates on the results for early death and fatal cancer for a large hypothetical release from a PWR

  7. Resource-recovery facilities: Production and cost functions, and debt-financing issues

    International Nuclear Information System (INIS)

    Simonsen, W.S.

    1991-01-01

    Some of the fiscal questions relating to resource-recovery, or trash-burning, facilities are addressed. Production and cost functions for resource-recovery facilities are estimated using regression analysis. Whether or not there are returns to scale are addressed using the production and cost-function framework. Production functions are also estimated using data envelopment analysis (DEA), and results are compared to the regression results. DEA is a linear-program-based technique that can provide information about the production process. The data used to estimate the production and cost functions were collected from the Resource Recovery Yearbook. Once the decision is made to construct a resource-recovery facility, it needs to be financed. The high cost of these facilities usually prohibits financing construction out of regular operating revenues. Therefore, the issues a government faces when debt is used to finance a resource-recovery facility are analyzed. The most important public policy finding is that increasing economies of scale do not seem to be present for resource-recovery facilities

  8. Results from the Application of Uncertainty Methods in the CSNI Uncertainty Methods Study (UMS)

    International Nuclear Information System (INIS)

    Glaeser, H.

    2008-01-01

    Within licensing procedures there is the incentive to replace the conservative requirements for code application by a - best estimate - concept supplemented by an uncertainty analysis to account for predictive uncertainties of code results. Methods have been developed to quantify these uncertainties. The Uncertainty Methods Study (UMS) Group, following a mandate from CSNI, has compared five methods for calculating the uncertainty in the predictions of advanced -best estimate- thermal-hydraulic codes. Most of the methods identify and combine input uncertainties. The major differences between the predictions of the methods came from the choice of uncertain parameters and the quantification of the input uncertainties, i.e. the wideness of the uncertainty ranges. Therefore, suitable experimental and analytical information has to be selected to specify these uncertainty ranges or distributions. After the closure of the Uncertainty Method Study (UMS) and after the report was issued comparison calculations of experiment LSTF-SB-CL-18 were performed by University of Pisa using different versions of the RELAP 5 code. It turned out that the version used by two of the participants calculated a 170 K higher peak clad temperature compared with other versions using the same input deck. This may contribute to the differences of the upper limit of the uncertainty ranges.

  9. Cost-effectiveness of a complex workplace dietary intervention: an economic evaluation of the Food Choice at Work study

    Science.gov (United States)

    Fitzgerald, Sarah; Murphy, Aileen; Kirby, Ann; Geaney, Fiona; Perry, Ivan J

    2018-01-01

    Objective To evaluate the costs, benefits and cost-effectiveness of complex workplace dietary interventions, involving nutrition education and system-level dietary modification, from the perspective of healthcare providers and employers. Design Single-study economic evaluation of a cluster-controlled trial (Food Choice at Work (FCW) study) with 1-year follow-up. Setting Four multinational manufacturing workplaces in Cork, Ireland. Participants 517 randomly selected employees (18–65 years) from four workplaces. Interventions Cost data were obtained from the FCW study. Nutrition education included individual nutrition consultations, nutrition information (traffic light menu labelling, posters, leaflets and emails) and presentations. System-level dietary modification included menu modification (restriction of fat, sugar and salt), increase in fibre, fruit discounts, strategic positioning of healthier alternatives and portion size control. The combined intervention included nutrition education and system-level dietary modification. No intervention was implemented in the control. Outcomes The primary outcome was an improvement in health-related quality of life, measured using the EuroQoL 5 Dimensions 5 Levels questionnaire. The secondary outcome measure was reduction in absenteeism, which is measured in monetary amounts. Probabilistic sensitivity analysis (Monte Carlo simulation) assessed parameter uncertainty. Results The system-level intervention dominated the education and combined interventions. When compared with the control, the incremental cost-effectiveness ratio (€101.37/quality-adjusted life-year) is less than the nationally accepted ceiling ratio, so the system-level intervention can be considered cost-effective. The cost-effectiveness acceptability curve indicates there is some decision uncertainty surrounding this, arising from uncertainty surrounding the differences in effectiveness. These results are reiterated when the secondary outcome measure is

  10. Uncertainty in relative cost investigation

    International Nuclear Information System (INIS)

    Bunn, D.; Viahos, K.

    1989-01-01

    One of the consequences of the privatization of the Central Electricity Generating Board has been a weakening of the economic case for nuclear generation over coal. Nuclear has higher capital, but lower operating costs than coal and is therefore favoured in capital budgeting by discounting at lower rates of return. In the Sizewell case (in 1987), discounting at the public sector rate of 5 per cent favoured nuclear. However, the private sector will require higher rates of return, thus rendering nuclear less attractive. Hence the imposition by the government of a diversity constraint on the privatized industry to ensure that contracts are made for a minimum fraction of non-fossil (essentially nuclear) energy. An electricity capacity planning model was developed to estimate the costs of imposing various non-fossil energy constraints on the planning decision of a privatized electricity supply industry, as a function of various discount rates. Using a large-scale linear programming technique, the model optimizes over a 50 year horizon the schedule of installation, and mix of generating capacity, both with and without a minimum non-fossil constraint. The conclusion is that the opportunity cost of diversity may be a complex joint substation of more than one type of plant (eg coal and gas) depending on the discount rate. (author)

  11. Cost and cost-effectiveness analysis of a community mobilisation intervention to reduce intimate partner violence in Kampala, Uganda.

    Science.gov (United States)

    Michaels-Igbokwe, Christine; Abramsky, Tanya; Devries, Karen; Michau, Lori; Musuya, Tina; Watts, Charlotte

    2016-02-29

    Intimate partner violence (IPV) poses a major public health concern. To date there are few rigorous economic evaluations of interventions aimed at preventing IPV in low-income settings. This study provides a cost and cost effectiveness analysis of SASA!, a community mobilisation intervention to change social norms and prevent IPV. An economic evaluation alongside a cluster randomised controlled trial. Both financial and economic costs were collected retrospectively from the provider's perspective to generate total and unit cost estimates over four years of intervention programming. Univariate sensitivity analysis is conducted to estimate the impact of uncertainty in cost and outcome measures on results. The total cost of developing the SASA! Activist Kit is estimated as US$138,598. Total intervention costs over four years are estimated as US$553,252. The annual cost of supporting 351 activists to conduct SASA! activities was approximately US$389 per activist and the average cost per person reached in intervention communities was US$21 over the full course of the intervention, or US$5 annually. The primary trial outcome was past year experience of physical IPV with an estimated 1201 cases averted (90% CI: 97-2307 cases averted). The estimated cost per case of past year IPV averted was US$460. This study provides the first economic evaluation of a community mobilisation intervention aimed at preventing IPV. SASA! unit costs compare favourably with gender transformative interventions and support services for survivors of IPV. ClinicalTrials.gov # NCT00790959.

  12. Techniques for Conducting Effective Concept Design and Design-to-Cost Trade Studies

    Science.gov (United States)

    Di Pietro, David A.

    2015-01-01

    Concept design plays a central role in project success as its product effectively locks the majority of system life cycle cost. Such extraordinary leverage presents a business case for conducting concept design in a credible fashion, particularly for first-of-a-kind systems that advance the state of the art and that have high design uncertainty. A key challenge, however, is to know when credible design convergence has been achieved in such systems. Using a space system example, this paper characterizes the level of convergence needed for concept design in the context of technical and programmatic resource margins available in preliminary design and highlights the importance of design and cost evaluation learning curves in determining credible convergence. It also provides techniques for selecting trade study cases that promote objective concept evaluation, help reveal unknowns, and expedite convergence within the trade space and conveys general practices for conducting effective concept design-to-cost studies.

  13. Stochastic cost estimating in repository life-cycle cost analysis

    International Nuclear Information System (INIS)

    Tzemos, S.; Dippold, D.

    1986-01-01

    The conceptual development, the design, and the final construction and operation of a nuclear repository span many decades. Given this lengthy time frame, it is quite challenging to obtain a good approximation of the repository life-cycle cost. One can deal with this challenge by using an analytic method, the method of moments, to explicitly assess the uncertainty of the estimate. A series expansion is used to approximate the uncertainty distribution of the cost estimate. In this paper, the moment methodology is derived and is illustrated through a numerical example. The range of validity of the approximation is discussed. The method of moments is compared to the traditional stochastic cost estimating methods and found to provide more and better information on cost uncertainty. The tow methods converge to identical results as the number of convolved variables increases and approaches the range where the central limit theorem is valid

  14. Cost-Effectiveness Analysis of Three Leprosy Case Detection Methods in Northern Nigeria

    Science.gov (United States)

    Ezenduka, Charles; Post, Erik; John, Steven; Suraj, Abdulkarim; Namadi, Abdulahi; Onwujekwe, Obinna

    2012-01-01

    Background Despite several leprosy control measures in Nigeria, child proportion and disability grade 2 cases remain high while new cases have not significantly reduced, suggesting continuous spread of the disease. Hence, there is the need to review detection methods to enhance identification of early cases for effective control and prevention of permanent disability. This study evaluated the cost-effectiveness of three leprosy case detection methods in Northern Nigeria to identify the most cost-effective approach for detection of leprosy. Methods A cross-sectional study was carried out to evaluate the additional benefits of using several case detection methods in addition to routine practice in two north-eastern states of Nigeria. Primary and secondary data were collected from routine practice records and the Nigerian Tuberculosis and Leprosy Control Programme of 2009. The methods evaluated were Rapid Village Survey (RVS), Household Contact Examination (HCE) and Traditional Healers incentive method (TH). Effectiveness was measured as number of new leprosy cases detected and cost-effectiveness was expressed as cost per case detected. Costs were measured from both providers' and patients' perspectives. Additional costs and effects of each method were estimated by comparing each method against routine practise and expressed as incremental cost-effectiveness ratio (ICER). All costs were converted to the U.S. dollar at the 2010 exchange rate. Univariate sensitivity analysis was used to evaluate uncertainties around the ICER. Results The ICER for HCE was $142 per additional case detected at all contact levels and it was the most cost-effective method. At ICER of $194 per additional case detected, THs method detected more cases at a lower cost than the RVS, which was not cost-effective at $313 per additional case detected. Sensitivity analysis showed that varying the proportion of shared costs and subsistent wage for valuing unpaid time did not significantly change the

  15. Cost Effective Polymer Solar Cells Research and Education

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Sam-Shajing [Norfolk State Univ, Norfolk, VA (United States)

    2015-10-13

    The technical or research objective of this project is to investigate and develop new polymers and polymer based optoelectronic devices for potentially cost effective (or cost competitive), durable, lightweight, flexible, and high efficiency solar energy conversion applications. The educational objective of this project includes training of future generation scientists, particularly young, under-represented minority scientists, working in the areas related to the emerging organic/polymer based solar energy technologies and related optoelectronic devices. Graduate and undergraduate students will be directly involved in scientific research addressing issues related to the development of polymer based solar cell technology.

  16. Evaluation of advanced coal gasification combined-cycle systems under uncertainty

    International Nuclear Information System (INIS)

    Frey, H.C.; Rubin, E.S.

    1992-01-01

    Advanced integrated gasification combined cycle (IGCC) systems have not been commercially demonstrated, and uncertainties remain regarding their commercial-scale performance and cost. Therefore, a probabilistic evaluation method has been developed and applied to explicitly consider these uncertainties. The insights afforded by this method are illustrated for an IGCC design featuring a fixed-bed gasifier and a hot gas cleanup system. Detailed case studies are conducted to characterize uncertainties in key measures of process performance and cost, evaluate design trade-offs under uncertainty, identify research priorities, evaluate the potential benefits of additional research, compare results for different uncertainty assumptions, and compare the advanced IGCC system to a conventional system under uncertainty. The implications of probabilistic results for research planning and technology selection are discussed in this paper

  17. Optimization under Uncertainty of Site-Specific Turbine Configurations: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Quick, Julian; Dykes, Katherine; Graf, Peter; Zahle, Frederik

    2016-11-01

    Uncertainty affects many aspects of wind energy plant performance and cost. In this study, we explore opportunities for site-specific turbine configuration optimization that accounts for uncertainty in the wind resource. As a demonstration, a simple empirical model for wind plant cost of energy is used in an optimization under uncertainty to examine how different risk appetites affect the optimal selection of a turbine configuration for sites of different wind resource profiles. If there is unusually high uncertainty in the site wind resource, the optimal turbine configuration diverges from the deterministic case and a generally more conservative design is obtained with increasing risk aversion on the part of the designer.

  18. Cost-Effectiveness and Value of Information Analysis of Brief Interventions to Promote Physical Activity in Primary Care.

    Science.gov (United States)

    Gc, Vijay Singh; Suhrcke, Marc; Hardeman, Wendy; Sutton, Stephen; Wilson, Edward C F

    2018-01-01

    Brief interventions (BIs) delivered in primary care have shown potential to increase physical activity levels and may be cost-effective, at least in the short-term, when compared with usual care. Nevertheless, there is limited evidence on their longer term costs and health benefits. To estimate the cost-effectiveness of BIs to promote physical activity in primary care and to guide future research priorities using value of information analysis. A decision model was used to compare the cost-effectiveness of three classes of BIs that have been used, or could be used, to promote physical activity in primary care: 1) pedometer interventions, 2) advice/counseling on physical activity, and (3) action planning interventions. Published risk equations and data from the available literature or routine data sources were used to inform model parameters. Uncertainty was investigated with probabilistic sensitivity analysis, and value of information analysis was conducted to estimate the value of undertaking further research. In the base-case, pedometer interventions yielded the highest expected net benefit at a willingness to pay of £20,000 per quality-adjusted life-year. There was, however, a great deal of decision uncertainty: the expected value of perfect information surrounding the decision problem for the National Health Service Health Check population was estimated at £1.85 billion. Our analysis suggests that the use of pedometer BIs is the most cost-effective strategy to promote physical activity in primary care, and that there is potential value in further research into the cost-effectiveness of brief (i.e., <30 minutes) and very brief (i.e., <5 minutes) pedometer interventions in this setting. Copyright © 2018 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

  19. Deciding the way. Comparing energy risks: methodologies and issues

    International Nuclear Information System (INIS)

    Matsuki, Yoshio; Lee, R.

    1999-01-01

    The following major issues in comparative assessment of energy systems are discussed: target users; decision making process; subject policy-making; setting boundaries; aggregated health indicators; monetary valuation; long-term health effects; global warming; methods to reflect uncertainties. Suggestions for study approaches of the mentioned issues are proposed

  20. Facts and feelings : Framing effects in responses to uncertainties about high-voltage power lines

    NARCIS (Netherlands)

    de Vries, G.; de Bruijn, J.A.

    2017-01-01

    To ensure power supply security, electricity transmission system operators (TSOs) have to upscale high-voltage overhead power lines. However, upscaling frequently meets opposition. Opposition can be caused by uncertainties about risks and benefits and might lead to costly delays (Linder, 1995;

  1. Cost-Effectiveness Analysis of the Self-Management Program for Thai Patients with Metabolic Syndrome.

    Science.gov (United States)

    Sakulsupsiri, Anut; Sakthong, Phantipa; Winit-Watjana, Win

    2016-05-01

    Lifestyle modification programs are partly evaluated for their usefulness. This study aimed to assess the cost-effectiveness and healthy lifestyle persistence of a self-management program (SMP) for patients with metabolic syndrome (MetS) in Thai health care settings. A cost-effectiveness analysis was performed on the basis of an intervention study of 90 patients with MetS randomly allocated to the SMP and control groups. A Markov model with the Difference-in-Difference method was used to predict the lifetime costs from a societal perspective and quality-adjusted life-years (QALYs), of which 95% confidence intervals (CIs) were estimated by bootstrapping. The cost-effectiveness analysis, along with healthy lifestyle persistence, was performed using the discount rate of 3% per annum. Parameter uncertainties were identified using one-way and probabilistic sensitivity analyses. The lifetime costs tended to decrease in both groups. The SMP could save lifetime costs (-2310 baht; 95% CI -5960 to 1400) and gain QALYs (0.0098; 95% CI -0.0003 to 0.0190), compared with ordinary care. The probability of cost-effectiveness was 99.4% from the Monte-Carlo simulation, and the program was deemed cost-effective at dropout rates below 69% per year as determined by the threshold of 160,000 baht per QALY gained. The cost of macrovascular complications was the most influencing variable for the overall incremental cost-effectiveness ratio. The SMP provided by the health care settings is marginally cost-effective, and the persistence results support the implementation of the program to minimize the complications and economic burden of patients with MetS. Copyright © 2016 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

  2. Uncertainties in real-world decisions on medical technologies.

    Science.gov (United States)

    Lu, C Y

    2014-08-01

    Patients, clinicians, payers and policy makers face substantial uncertainties in their respective healthcare decisions as they attempt to achieve maximum value, or the greatest level of benefit possible at a given cost. Uncertainties largely come from incomplete information at the time that decisions must be made. This is true in all areas of medicine because evidence from clinical trials is often incongruent with real-world patient care. This article highlights key uncertainties around the (comparative) benefits and harms of medical technologies. Initiatives and strategies such as comparative effectiveness research and coverage with evidence development may help to generate reliable and relevant evidence for decisions on coverage and treatment. These efforts could result in better decisions that improve patient outcomes and better use of scarce medical resources. © 2014 John Wiley & Sons Ltd.

  3. The Long-Term Effectiveness and Cost Effectiveness of Organized versus Opportunistic Screening for Breast Cancer in Austria.

    Science.gov (United States)

    Schiller-Fruehwirth, Irmgard; Jahn, Beate; Einzinger, Patrick; Zauner, Günther; Urach, Christoph; Siebert, Uwe

    2017-09-01

    In 2014, Austrian health authorities implemented an organized breast cancer screening program. Until then, there has been a long-standing tradition of opportunistic screening. To evaluate the cost-effectiveness of organized screening compared with opportunistic screening, as well as to identify factors influencing the clinical and economic outcomes. We developed and validated an individual-level state-transition model and assessed the health outcomes and costs of organized and opportunistic screening for 40-year-old asymptomatic women. The base-case analysis compared a scenario involving organized biennial screening with a scenario reflecting opportunistic screening practice for an average-risk woman aged 45 to 69 years. We applied an annual discount rate of 3% and estimated the incremental cost-effectiveness ratio in terms of the cost (2012 euros) per life-year gained (LYG) from a health care perspective. Deterministic and probabilistic sensitivity analyses were performed to assess uncertainty. Compared with opportunistic screening, an organized program yielded on average additional 0.0118 undiscounted life-years (i.e., 4.3 days) and cost savings of €41 per woman. In the base-case analysis, the incremental cost-effectiveness ratio of organized screening was approximately €20,000 per LYG compared with no screening. Assuming a willingness-to-pay threshold of €50,000 per LYG, there was a 70% probability that organized screening would be considered cost-effective. The attendance rate, but not the test accuracy of mammography, was an influential factor for the cost-effectiveness. The decision to adopt organized screening is likely an efficient use of limited health care resources in Austria. Copyright © 2017 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

  4. Cost-effectiveness of additional catheter-directed thrombolysis for deep vein thrombosis

    Science.gov (United States)

    ENDEN, T.; RESCH, S.; WHITE, C.; WIK, H. S.; KLØW, N. E.; SANDSET, P. M.

    2013-01-01

    Summary Background Additional treatment with catheter-directed thrombolysis (CDT) has recently been shown to reduce post-thrombotic syndrome (PTS). Objectives To estimate the cost effectiveness of additional CDT compared with standard treatment alone. Methods Using a Markov decision model, we compared the two treatment strategies in patients with a high proximal deep vein thrombosis (DVT) and a low risk of bleeding. The model captured the development of PTS, recurrent venous thromboembolism and treatment-related adverse events within a lifetime horizon and the perspective of a third-party payer. Uncertainty was assessed with one-way and probabilistic sensitivity analyzes. Model inputs from the CaVenT study included PTS development, major bleeding from CDT and utilities for post DVT states including PTS. The remaining clinical inputs were obtained from the literature. Costs obtained from the CaVenT study, hospital accounts and the literature are expressed in US dollars ($); effects in quality adjusted life years (QALY). Results In base case analyzes, additional CDT accumulated 32.31 QALYs compared with 31.68 QALYs after standard treatment alone. Direct medical costs were $64 709 for additional CDT and $51 866 for standard treatment. The incremental cost-effectiveness ratio (ICER) was $20 429/QALY gained. One-way sensitivity analysis showed model sensitivity to the clinical efficacy of both strategies, but the ICER remained < $55 000/QALY over the full range of all parameters. The probability that CDT is cost effective was 82% at a willingness to pay threshold of $50 000/QALY gained. Conclusions Additional CDT is likely to be a cost-effective alternative to the standard treatment for patients with a high proximal DVT and a low risk of bleeding. PMID:23452204

  5. Cost-effectiveness of Rotavirus vaccination in Vietnam

    Directory of Open Access Journals (Sweden)

    Goldie Sue J

    2009-01-01

    Introducing rotavirus vaccines would be a cost-effective public health intervention in Vietnam. However, given the uncertainty about vaccine efficacy and potential changes in rotavirus epidemiology in local settings, further clinical research and re-evaluation of rotavirus vaccination programs may be necessary as new information emerges.

  6. LOFT experimental measurements uncertainty analyses. Volume XX. Fluid-velocity measurement using pulsed-neutron activation

    International Nuclear Information System (INIS)

    Lassahn, G.D.; Taylor, D.J.N.

    1982-08-01

    Analyses of uncertainty components inherent in pulsed-neutron-activation (PNA) measurements in general and the Loss-of-Fluid-Test (LOFT) system in particular are given. Due to the LOFT system's unique conditions, previously-used techniques were modified to make the volocity measurement. These methods render a useful, cost-effective measurement with an estimated uncertainty of 11% of reading

  7. Cost-effectiveness of screening for asymptomatic carotid atherosclerotic disease.

    Science.gov (United States)

    Derdeyn, C P; Powers, W J

    1996-11-01

    The value of screening for asymptomatic carotid stenosis has become an important issue with the recently reported beneficial effect of endarterectomy. The purpose of this study is to evaluate the cost-effectiveness of using Doppler ultrasound as a screening tool to select subjects for arteriography and subsequent surgery. A computer model was developed to simulate the cost-effectiveness of screening a cohort of 1000 men during a 20-year period. The primary outcome measure was incremental present-value dollar expenditures for screening and treatment per incremental present-value quality-adjusted life-year (QALY) saved. Estimates of disease prevalence and arteriographic and surgical complication rates were obtained from the literature. Probabilities of stroke and death with surgical and medical treatment were obtained from published clinical trials. Doppler ultrasound sensitivity and specificity were obtained through review of local experience. Estimates of costs were obtained from local Medicare reimbursement data. A one-time screening program of a population with a high prevalence (20%) of > or = 60% stenosis cost $35130 per incremental QALY gained. Decreased surgical benefit or increased annual discount rate was detrimental, resulting in lost QALYs. Annual screening cost $457773 per incremental QALY gained. In a low-prevalence (4%) population, one-time screening cost $52588 per QALY gained, while annual screening was detrimental. The cost-effectiveness of a one-time screening program for an asymptomatic population with a high prevalence of carotid stenosis may be cost-effective. Annual screening is detrimental. The most sensitive variables in this simulation model were long-term stroke risk reduction after surgery and annual discount rate for accumulated costs and QALYs.

  8. Frequent price changes under menu costs

    DEFF Research Database (Denmark)

    Hansen, Per Svejstrup

    1999-01-01

    , the price may be changed more frequent in the short run, and in the long run it definitely will. Hence, observing frequent price changes is not necessarily inconsistent with a firm operating under menu costs. This paper relies on an article by Dixit (1991), (Review of Economic studies, 58, 141......This paper investigates the effect of uncertainty on a single firm's pricing behaviour in a dynamic menu cost model that results in (S,s)-rules where the price is fixed inside a band. It will be demonstrated that even though the band of inaction widens in response to increased uncertainty...

  9. Priority Setting, Cost-Effectiveness, and the Affordable Care Act.

    Science.gov (United States)

    Persad, Govind

    2015-01-01

    The Affordable Care Act (ACA) may be the most important health law statute in American history, yet much of the most prominent legal scholarship examining it has focused on the merits of the court challenges it has faced rather than delving into the details of its priority-setting provisions. In addition to providing an overview of the ACA's provisions concerning priority setting and their developing interpretations, this Article attempts to defend three substantive propositions. First, I argue that the ACA is neither uniformly hostile nor uniformly friendly to efforts to set priorities in ways that promote cost and quality. Second, I argue that the ACA does not take a single, unified approach to priority setting; rather, its guidance varies depending on the aspect of the healthcare system at issue (Patient Centered Outcomes Research Institute, Medicare, essential health benefits) and the factors being excluded from priority setting (age, disability, life expectancy). Third, I argue that cost-effectiveness can be achieved within the ACA's constraints, but that doing so will require adopting new approaches to cost-effectiveness and priority setting. By limiting the use of standard cost-effectiveness analysis, the ACA makes the need for workable rivals to cost-effectiveness analysis a pressing practical concern rather than a mere theoretical worry.

  10. Cost-effectiveness of interventions to promote physical activity: a modelling study.

    Directory of Open Access Journals (Sweden)

    Linda J Cobiac

    2009-07-01

    . CONCLUSIONS: Intervention to promote physical activity is recommended as a public health measure. Despite substantial variability in the quantity and quality of evidence on intervention effectiveness, and uncertainty about the long-term sustainability of behavioural changes, it is highly likely that as a package, all six interventions could lead to substantial improvement in population health at a cost saving to the health sector. Please see later in the article for Editors' Summary.

  11. Planning low-carbon electricity systems under uncertainty considering operational flexibility and smart grid technologies.

    Science.gov (United States)

    Moreno, Rodrigo; Street, Alexandre; Arroyo, José M; Mancarella, Pierluigi

    2017-08-13

    Electricity grid operators and planners need to deal with both the rapidly increasing integration of renewables and an unprecedented level of uncertainty that originates from unknown generation outputs, changing commercial and regulatory frameworks aimed to foster low-carbon technologies, the evolving availability of market information on feasibility and costs of various technologies, etc. In this context, there is a significant risk of locking-in to inefficient investment planning solutions determined by current deterministic engineering practices that neither capture uncertainty nor represent the actual operation of the planned infrastructure under high penetration of renewables. We therefore present an alternative optimization framework to plan electricity grids that deals with uncertain scenarios and represents increased operational details. The presented framework is able to model the effects of an array of flexible, smart grid technologies that can efficiently displace the need for conventional solutions. We then argue, and demonstrate via the proposed framework and an illustrative example, that proper modelling of uncertainty and operational constraints in planning is key to valuing operationally flexible solutions leading to optimal investment in a smart grid context. Finally, we review the most used practices in power system planning under uncertainty, highlight the challenges of incorporating operational aspects and advocate the need for new and computationally effective optimization tools to properly value the benefits of flexible, smart grid solutions in planning. Such tools are essential to accelerate the development of a low-carbon energy system and investment in the most appropriate portfolio of renewable energy sources and complementary enabling smart technologies.This article is part of the themed issue 'Energy management: flexibility, risk and optimization'. © 2017 The Author(s).

  12. Effect of matrix cracking and material uncertainty on composite plates

    International Nuclear Information System (INIS)

    Gayathri, P.; Umesh, K.; Ganguli, R.

    2010-01-01

    A laminated composite plate model based on first order shear deformation theory is implemented using the finite element method. Matrix cracks are introduced into the finite element model by considering changes in the A, B and D matrices of composites. The effects of different boundary conditions, laminate types and ply angles on the behavior of composite plates with matrix cracks are studied. Finally, the effect of material property uncertainty, which is important for composite material on the composite plate, is investigated using Monte Carlo simulations. Probabilistic estimates of damage detection reliability in composite plates are made for static and dynamic measurements. It is found that the effect of uncertainty must be considered for accurate damage detection in composite structures. The estimates of variance obtained for observable system properties due to uncertainty can be used for developing more robust damage detection algorithms.

  13. WPDD workshop on: 'safe, efficient, and cost-effective decommissioning'. Workshop Conclusions/Final Stocktaking

    International Nuclear Information System (INIS)

    2005-01-01

    . - Financial mechanisms for decommissioning funding are evolving in the NEA member states to meet regulatory and project needs. Continuing challenges are uncertainties in cost estimates and the implementation of measures to assure that funds will be available when required. - Creative research on decommissioning is being carried out. Human factors and organisational issues are studied. Practical solutions are being implemented such as the use of management transition programmes. Some increased efficiency and effectiveness is needed by way of R and D on improving technology and developing innovative techniques, subject to justification of its cost and value. There is a need to consider how to design commercial contracts so that decommissioning contractors will be willing to test new, relatively unproven techniques. - Continuing emphasis on education in critical nuclear skills is needed to ensure availability of the necessary expertise for both near-term decommissioning needs and long-term energy needs. - Public acceptance is still a major challenge. Without public acceptance, decommissioning may be prolonged and difficult to implement. Hence, all actors and interested parties need to be constructively involved in the dialogue within the local communities to gather and evaluate all relevant concerns and thereby inspire confidence in the safety of decommissioning activities

  14. Uncertainty Aware Structural Topology Optimization Via a Stochastic Reduced Order Model Approach

    Science.gov (United States)

    Aguilo, Miguel A.; Warner, James E.

    2017-01-01

    This work presents a stochastic reduced order modeling strategy for the quantification and propagation of uncertainties in topology optimization. Uncertainty aware optimization problems can be computationally complex due to the substantial number of model evaluations that are necessary to accurately quantify and propagate uncertainties. This computational complexity is greatly magnified if a high-fidelity, physics-based numerical model is used for the topology optimization calculations. Stochastic reduced order model (SROM) methods are applied here to effectively 1) alleviate the prohibitive computational cost associated with an uncertainty aware topology optimization problem; and 2) quantify and propagate the inherent uncertainties due to design imperfections. A generic SROM framework that transforms the uncertainty aware, stochastic topology optimization problem into a deterministic optimization problem that relies only on independent calls to a deterministic numerical model is presented. This approach facilitates the use of existing optimization and modeling tools to accurately solve the uncertainty aware topology optimization problems in a fraction of the computational demand required by Monte Carlo methods. Finally, an example in structural topology optimization is presented to demonstrate the effectiveness of the proposed uncertainty aware structural topology optimization approach.

  15. Saving lives and saving money: hospital-based violence intervention is cost-effective.

    Science.gov (United States)

    Juillard, Catherine; Smith, Randi; Anaya, Nancy; Garcia, Arturo; Kahn, James G; Dicker, Rochelle A

    2015-02-01

    Victims of violence are at significant risk for injury recidivism, including fatality. We previously demonstrated that our hospital-based violence intervention program (VIP) resulted in a fourfold reduction in injury recidivism, avoiding trauma care costs of $41,000 per injury. Given limited trauma center resources, assessing cost-effectiveness of interventions is fundamental to inform use of these programs in other institutions. This study examines the cost-effectiveness of hospital-based VIP. We used a decision tree and Markov disease state modeling to analyze cost utility for a hypothetical cohort of violently injured subjects, comparing VIP versus no VIP at a trauma center. Quality-adjusted life-years (QALYs) were calculated using differences in mortality and published health state utilities. Costs of trauma care and VIP were obtained from institutional data, and risk of recidivism with and without VIP were obtained from our trial. Outcomes were QALYs gained and net costs over a 5-year horizon. Sensitivity analyses examined the impact of uncertainty in input values on results. VIP results in an estimated 25.58 QALYs and net costs (program plus trauma care) of $5,892 per patient. Without VIP, these values are 25.34 and $5,923, respectively, suggesting that VIP yields substantial health benefits (24 QALYs) and savings ($4,100) if implemented for 100 individuals. In the sensitivity analysis, net QALYs gained with VIP nearly triple when the injury recidivism rate without VIP is highest. Cost-effectiveness remained robust over a range of values; $6,000 net cost savings occur when 5-year recidivism rate without VIP is at 7%. VIP costs less than having no VIP with significant gains in QALYs especially at anticipated program scale. Across a range of plausible values at which VIP would be less cost-effective (lower injury recidivism, cost of injury, and program effectiveness), VIP still results in acceptable cost per health outcome gained. VIP is effective and cost-effective

  16. Cost-effectiveness of diet and exercise interventions to reduce overweight and obesity.

    Science.gov (United States)

    Forster, M; Veerman, J L; Barendregt, J J; Vos, T

    2011-08-01

    To analyze whether two dietary weight loss interventions--the dietary approaches to stop hypertension (DASH) program and a low-fat diet program--would be cost-effective in Australia, and to assess their potential to reduce the disease burden related to excess body weight. We constructed a multi-state life-table-based Markov model in which the distribution of body weight influences the incidence of stroke, ischemic heart disease, hypertensive heart disease, diabetes mellitus, osteoarthritis, post-menopausal breast cancer, colon cancer, endometrial cancer and kidney cancer. The target population was the overweight and obese adult population in Australia in 2003. We used a lifetime horizon for health effects and costs, and a health sector perspective for costs. We populated the model with data identified from Medline and Cochrane searches, Australian Bureau of Statistics published catalogues, Australian Institute of Health and Welfare, and Department of Health and Ageing. Disability adjusted life years (DALYs) averted, incremental cost-effectiveness ratios (ICERs) and proportions of disease burden avoided. ICERs under AUS$50,000 per DALY are considered cost-effective. The DASH and low-fat diet programs have ICERs of AUS$12,000 per DALY (95% uncertainty range: Cost-saving- 68,000) and AUS$13,000 per DALY (Cost-saving--130,000), respectively. Neither intervention reduced the body weight-related disease burden at population level by more than 0.1%. The sensitivity analysis showed that when participants' costs for time and travel are included, the ICERs increase to AUS$75,000 per DALY for DASH and AUS$49,000 per DALY for the low-fat diet. Modest weight loss during the interventions, post-intervention weight regain and low participation limit the health benefits. Diet and exercise interventions to reduce obesity are potentially cost-effective but have a negligible impact on the total body weight-related disease burden.

  17. effect of uncertainty on the fatigue reliability of reinforced concrete ...

    African Journals Online (AJOL)

    In this paper, a reliability time-variant fatigue analysis and uncertainty effect on the serviceability of reinforced concrete bridge deck was carried out. A simply supported 15m bridge deck was specifically used for the investigation. Mathematical models were developed and the uncertainties in structural resistance, applied ...

  18. Section summary: Uncertainty and design considerations

    Science.gov (United States)

    Stephen Hagen

    2013-01-01

    Well planned sampling designs and robust approaches to estimating uncertainty are critical components of forest monitoring. The importance of uncertainty estimation increases as deforestation and degradation issues become more closely tied to financing incentives for reducing greenhouse gas emissions in the forest sector. Investors like to know risk and risk is tightly...

  19. Urban drainage models - making uncertainty analysis simple

    DEFF Research Database (Denmark)

    Vezzaro, Luca; Mikkelsen, Peter Steen; Deletic, Ana

    2012-01-01

    in each measured/observed datapoint; an issue which is commonly overlook in the uncertainty analysis of urban drainage models. This comparison allows the user to intuitively estimate the optimum number of simulations required to conduct uncertainty analyses. The output of the method includes parameter......There is increasing awareness about uncertainties in modelling of urban drainage systems and, as such, many new methods for uncertainty analyses have been developed. Despite this, all available methods have limitations which restrict their widespread application among practitioners. Here...

  20. Comparison of Strategies and Incidence Thresholds for Vi Conjugate Vaccines Against Typhoid Fever: A Cost-effectiveness Modeling Study.

    Science.gov (United States)

    Lo, Nathan C; Gupta, Ribhav; Stanaway, Jeffrey D; Garrett, Denise O; Bogoch, Isaac I; Luby, Stephen P; Andrews, Jason R

    2018-02-12

    Typhoid fever remains a major public health problem globally. While new Vi conjugate vaccines hold promise for averting disease, the optimal programmatic delivery remains unclear. We aimed to identify the strategies and associated epidemiologic conditions under which Vi conjugate vaccines would be cost-effective. We developed a dynamic, age-structured transmission and cost-effectiveness model that simulated multiple vaccination strategies with a typhoid Vi conjugate vaccine from a societal perspective. We simulated 10-year vaccination programs with (1) routine immunization of infants (aged typhoid fever and defined strategies as highly cost-effective by using the definition of a low-income country (defined as a country with a gross domestic product of $1045 per capita). We defined incidence as the true number of clinically symptomatic people in the population per year. Vi conjugate typhoid vaccines were highly cost-effective when administered by routine immunization activities through the EPI in settings with an annual incidence of >50 cases/100000 (95% uncertainty interval, 40-75 cases) and when administered through the EPI plus a catch-up campaign in settings with an annual incidence of >130 cases/100000 (95% uncertainty interval, 50-395 cases). The incidence threshold was sensitive to the typhoid-related case-fatality rate, carrier contribution to transmission, vaccine characteristics, and country-specific economic threshold for cost-effectiveness. Typhoid Vi conjugate vaccines would be highly cost-effective in low-income countries in settings of moderate typhoid incidence (50 cases/100000 annually). These results were sensitive to case-fatality rates, underscoring the need to consider factors contributing to typhoid mortality (eg, healthcare access and antimicrobial resistance) in the global vaccination strategy. © The Author(s) 2018. Published by Oxford University Press for the Infectious Diseases Society of America.

  1. Generalized uncertainty principle as a consequence of the effective field theory

    Energy Technology Data Exchange (ETDEWEB)

    Faizal, Mir, E-mail: mirfaizalmir@gmail.com [Irving K. Barber School of Arts and Sciences, University of British Columbia – Okanagan, Kelowna, British Columbia V1V 1V7 (Canada); Department of Physics and Astronomy, University of Lethbridge, Lethbridge, Alberta T1K 3M4 (Canada); Ali, Ahmed Farag, E-mail: ahmed.ali@fsc.bu.edu.eg [Department of Physics, Faculty of Science, Benha University, Benha, 13518 (Egypt); Netherlands Institute for Advanced Study, Korte Spinhuissteeg 3, 1012 CG Amsterdam (Netherlands); Nassar, Ali, E-mail: anassar@zewailcity.edu.eg [Department of Physics, Zewail City of Science and Technology, 12588, Giza (Egypt)

    2017-02-10

    We will demonstrate that the generalized uncertainty principle exists because of the derivative expansion in the effective field theories. This is because in the framework of the effective field theories, the minimum measurable length scale has to be integrated away to obtain the low energy effective action. We will analyze the deformation of a massive free scalar field theory by the generalized uncertainty principle, and demonstrate that the minimum measurable length scale corresponds to a second more massive scale in the theory, which has been integrated away. We will also analyze CFT operators dual to this deformed scalar field theory, and observe that scaling of the new CFT operators indicates that they are dual to this more massive scale in the theory. We will use holographic renormalization to explicitly calculate the renormalized boundary action with counter terms for this scalar field theory deformed by generalized uncertainty principle, and show that the generalized uncertainty principle contributes to the matter conformal anomaly.

  2. Generalized uncertainty principle as a consequence of the effective field theory

    Directory of Open Access Journals (Sweden)

    Mir Faizal

    2017-02-01

    Full Text Available We will demonstrate that the generalized uncertainty principle exists because of the derivative expansion in the effective field theories. This is because in the framework of the effective field theories, the minimum measurable length scale has to be integrated away to obtain the low energy effective action. We will analyze the deformation of a massive free scalar field theory by the generalized uncertainty principle, and demonstrate that the minimum measurable length scale corresponds to a second more massive scale in the theory, which has been integrated away. We will also analyze CFT operators dual to this deformed scalar field theory, and observe that scaling of the new CFT operators indicates that they are dual to this more massive scale in the theory. We will use holographic renormalization to explicitly calculate the renormalized boundary action with counter terms for this scalar field theory deformed by generalized uncertainty principle, and show that the generalized uncertainty principle contributes to the matter conformal anomaly.

  3. Analysis of multi-pollutant policies for the U.S. power sector under technology and policy uncertainty using MARKAL

    International Nuclear Information System (INIS)

    Hu, Ming-Che; Hobbs, Benjamin F.

    2010-01-01

    Investments in power generation, pollution controls, and electricity end use equipment are made in the face of uncertainty. Unanticipated events can cause regret-commitments that in retrospect were the wrong choices. We analyze how three uncertainties-electricity demand growth, natural gas prices, and power sector greenhouse gas regulations-could affect electric power sector investment decisions and costs in the U.S. over the next four decades. The effect of multi-pollutant regulations such as the Clean Air Interstate Rule (CAIR) upon these decisions and costs is also considered. We use decision trees to structure the problem, defining multiple futures for each uncertainty and then simulating how the U.S. energy market responds to them. A two-stage stochastic version of the energy-economy model MARKAL simulates the market. Relative importance of the uncertainties is assessed using two indices: expected cost of ignoring uncertainty (ECIU) and expected value of perfect information (EVPI). We also calculate the value of policy coordination (VPC), the cost saved by avoiding surprise changes in policy. An example shows how a stochastic program can be used to compute these indices. The analysis shows that the possibility of greenhouse gas regulation is the most important uncertainty by these measures.

  4. Cost-effectiveness of pneumococcal conjugate vaccination in Croatia.

    Science.gov (United States)

    Vučina, V Višekruna; Filipović, S Kurečić; Kožnjak, N; Stamenić, V; Clark, A D; Mounaud, B; Blau, J; Hoestlandt, C; Kaić, B

    2015-05-07

    were borderline cost-effective (US$ per DALY averted less than 3×GDP per capita of approximately US$ 40,000). The first was a scenario based primarily on the WHO 2008 pneumococcal disease burden estimates for Croatia. The second was a scenario that assumed a fairly dramatic drop in the price of the vaccine over the period. Both vaccines would need to be priced at approximately US$ 20 per dose or less to be considered cost-effective under base-case assumptions. PCV10 would be more cost-effective than PCV13 with base-case assumptions, but this is sensitive to the price of each vaccine. Based on estimated health and economic benefits in children alone, PCV is unlikely to be cost-effective in Croatia. Both vaccines would need to be priced at less than US$ 20 per dose to be considered cost-effective for children. Further analyses should be conducted to estimate the health and economic burden of pneumococcal disease in older age groups, and to assess the influence on cost-effectiveness results when short-term and long-term indirect effects are included for older individuals. While there are important uncertainties around the price and effectiveness of both vaccines, our analysis suggests there is insufficient evidence to warrant a significant difference in the price of the two vaccines. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Cost-effectiveness of drug-eluting stents versus bare-metal stents in patients undergoing percutaneous coronary intervention.

    Science.gov (United States)

    Baschet, Louise; Bourguignon, Sandrine; Marque, Sébastien; Durand-Zaleski, Isabelle; Teiger, Emmanuel; Wilquin, Fanny; Levesque, Karine

    2016-01-01

    To determine the cost-effectiveness of drug-eluting stents (DES) compared with bare-metal stents (BMS) in patients requiring a percutaneous coronary intervention in France, using a recent meta-analysis including second-generation DES. A cost-effectiveness analysis was performed in the French National Health Insurance setting. Effectiveness settings were taken from a meta-analysis of 117 762 patient-years with 76 randomised trials. The main effectiveness criterion was major cardiac event-free survival. Effectiveness and costs were modelled over a 5-year horizon using a three-state Markov model. Incremental cost-effectiveness ratios and a cost-effectiveness acceptability curve were calculated for a range of thresholds for willingness to pay per year without major cardiac event gain. Deterministic and probabilistic sensitivity analyses were performed. Base case results demonstrated that DES are dominant over BMS, with an increase in event-free survival and a cost-reduction of €184, primarily due to a diminution of second revascularisations, and an absence of myocardial infarction and stent thrombosis. These results are robust for uncertainty on one-way deterministic and probabilistic sensitivity analyses. Using a cost-effectiveness threshold of €7000 per major cardiac event-free year gained, DES has a >95% probability of being cost-effective versus BMS. Following DES price decrease, new-generation DES development and taking into account recent meta-analyses results, the DES can now be considered cost-effective regardless of selective indication in France, according to European recommendations.

  6. Using finite mixture models in thermal-hydraulics system code uncertainty analysis

    Energy Technology Data Exchange (ETDEWEB)

    Carlos, S., E-mail: scarlos@iqn.upv.es [Department d’Enginyeria Química i Nuclear, Universitat Politècnica de València, Camí de Vera s.n, 46022 València (Spain); Sánchez, A. [Department d’Estadística Aplicada i Qualitat, Universitat Politècnica de València, Camí de Vera s.n, 46022 València (Spain); Ginestar, D. [Department de Matemàtica Aplicada, Universitat Politècnica de València, Camí de Vera s.n, 46022 València (Spain); Martorell, S. [Department d’Enginyeria Química i Nuclear, Universitat Politècnica de València, Camí de Vera s.n, 46022 València (Spain)

    2013-09-15

    Highlights: • Best estimate codes simulation needs uncertainty quantification. • The output variables can present multimodal probability distributions. • The analysis of multimodal distribution is performed using finite mixture models. • Two methods to reconstruct output variable probability distribution are used. -- Abstract: Nuclear Power Plant safety analysis is mainly based on the use of best estimate (BE) codes that predict the plant behavior under normal or accidental conditions. As the BE codes introduce uncertainties due to uncertainty in input parameters and modeling, it is necessary to perform uncertainty assessment (UA), and eventually sensitivity analysis (SA), of the results obtained. These analyses are part of the appropriate treatment of uncertainties imposed by current regulation based on the adoption of the best estimate plus uncertainty (BEPU) approach. The most popular approach for uncertainty assessment, based on Wilks’ method, obtains a tolerance/confidence interval, but it does not completely characterize the output variable behavior, which is required for an extended UA and SA. However, the development of standard UA and SA impose high computational cost due to the large number of simulations needed. In order to obtain more information about the output variable and, at the same time, to keep computational cost as low as possible, there has been a recent shift toward developing metamodels (model of model), or surrogate models, that approximate or emulate complex computer codes. In this way, there exist different techniques to reconstruct the probability distribution using the information provided by a sample of values as, for example, the finite mixture models. In this paper, the Expectation Maximization and the k-means algorithms are used to obtain a finite mixture model that reconstructs the output variable probability distribution from data obtained with RELAP-5 simulations. Both methodologies have been applied to a separated

  7. Uncertainty Margin of Void Packet Determination for Ultrasonic Test in NPP

    International Nuclear Information System (INIS)

    Lee, Seungchan; Sung, Jejung; Lee, Jongchan; Kim, Jonguk

    2014-01-01

    In this study, the uncertainty of the void packet determination is estimated and the conservatism is reviewed by comparing with realistic uncertainty of Heckle's uncertainty. The methodology of ISO GUM is fully applied to calculate uncertainty, combined uncertainty and effective degree of freedom. Here some results are achieved as below: Combined uncertainty(UT) : 4.98%, Combined uncertainty(Heckle) : 1.44%, Degree of freedom: 5 ∼ 15, Effective degree of freedom(UT): 24.11, Effective degree of freedom(Heckle): 28.54, K value of t-distribution(UT): 2.042, K value of t-distribution(Heckle): 2.04, The uncertainty of this study using UT is enough in the case of achieving conservatism when the void packet determination of the safety related system is determined. As result of this study, UT uncertainty is more conservative than the Heckle's realistic uncertainty. From these results, it is shown that UT method has the great safety margin in determining the void packet. In comparing UT uncertainty with realistic uncertainty, this study (UT) has the conservatism of more than 3.4 times. UT method is good method to determine the void packet of ECCS pipe and to achieve the safety margin. In a safety related system, a void packet determination is issued by US NRC through the Generic Letter 2008-01. In case of the safety function, ECCS, CSS, and RHR systems are affected by the void packet. The related study has been being carried out by KHNP since 2012. In this study, the void packet determination using a ultra sonic test method has been carried out in some sites. This paper shows the uncertainty of the method using the ultra sonic test. The key parameters are introduced and estimated. Specially, the measurement conservatism for NPP is introduced to show the uncertainty margin

  8. Uncertainty Margin of Void Packet Determination for Ultrasonic Test in NPP

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seungchan; Sung, Jejung [Korea Hydro Nuclear Power Electricity Co., Daejeon (Korea, Republic of); Lee, Jongchan; Kim, Jonguk [FNC Technology Co., LTD., Yongin (Korea, Republic of)

    2014-05-15

    In this study, the uncertainty of the void packet determination is estimated and the conservatism is reviewed by comparing with realistic uncertainty of Heckle's uncertainty. The methodology of ISO GUM is fully applied to calculate uncertainty, combined uncertainty and effective degree of freedom. Here some results are achieved as below: Combined uncertainty(UT) : 4.98%, Combined uncertainty(Heckle) : 1.44%, Degree of freedom: 5 ∼ 15, Effective degree of freedom(UT): 24.11, Effective degree of freedom(Heckle): 28.54, K value of t-distribution(UT): 2.042, K value of t-distribution(Heckle): 2.04, The uncertainty of this study using UT is enough in the case of achieving conservatism when the void packet determination of the safety related system is determined. As result of this study, UT uncertainty is more conservative than the Heckle's realistic uncertainty. From these results, it is shown that UT method has the great safety margin in determining the void packet. In comparing UT uncertainty with realistic uncertainty, this study (UT) has the conservatism of more than 3.4 times. UT method is good method to determine the void packet of ECCS pipe and to achieve the safety margin. In a safety related system, a void packet determination is issued by US NRC through the Generic Letter 2008-01. In case of the safety function, ECCS, CSS, and RHR systems are affected by the void packet. The related study has been being carried out by KHNP since 2012. In this study, the void packet determination using a ultra sonic test method has been carried out in some sites. This paper shows the uncertainty of the method using the ultra sonic test. The key parameters are introduced and estimated. Specially, the measurement conservatism for NPP is introduced to show the uncertainty margin.

  9. Decision making under uncertainty: An investigation into the application of formal decision-making methods to safety issue decisions

    International Nuclear Information System (INIS)

    Bohn, M.P.

    1992-12-01

    As part of the NRC-sponsored program to study the implications of Generic Issue 57, ''Effects of Fire Protection System Actuation on Safety-Related Equipment,'' a subtask was performed to evaluate the applicability of formal decision analysis methods to generic issues cost/benefit-type decisions and to apply these methods to the GI-57 results. In this report, the numerical results obtained from the analysis of three plants (two PWRs and one BWR) as developed in the technical resolution program for GI-57 were studied. For each plant, these results included a calculation of the person-REM averted due to various accident scenarios and various proposed modifications to mitigate the accident scenarios identified. These results were recomputed to break out the benefit in terms of contributions due to random event scenarios, fire event scenarios, and seismic event scenarios. Furthermore, the benefits associated with risk (in terms of person-REM) averted from earthquakes at three different seismic ground motion levels were separately considered. Given this data, formal decision methodologies involving decision trees, value functions, and utility functions were applied to this basic data. It is shown that the formal decision methodology can be applied at several different levels. Examples are given in which the decision between several retrofits is changed from that resulting from a simple cost/benefit-ratio criterion by virtue of the decision-makinger's expressed (and assumed) preferences

  10. Model Uncertainties for Valencia RPA Effect for MINERvA

    Energy Technology Data Exchange (ETDEWEB)

    Gran, Richard [Univ. of Minnesota, Duluth, MN (United States)

    2017-05-08

    This technical note describes the application of the Valencia RPA multi-nucleon effect and its uncertainty to QE reactions from the GENIE neutrino event generator. The analysis of MINERvA neutrino data in Rodrigues et al. PRL 116 071802 (2016) paper makes clear the need for an RPA suppression, especially at very low momentum and energy transfer. That published analysis does not constrain the magnitude of the effect; it only tests models with and without the effect against the data. Other MINERvA analyses need an expression of the model uncertainty in the RPA effect. A well-described uncertainty can be used for systematics for unfolding, for model errors in the analysis of non-QE samples, and as input for fitting exercises for model testing or constraining backgrounds. This prescription takes uncertainties on the parameters in the Valencia RPA model and adds a (not-as-tight) constraint from muon capture data. For MINERvA we apply it as a 2D ($q_0$,$q_3$) weight to GENIE events, in lieu of generating a full beyond-Fermi-gas quasielastic events. Because it is a weight, it can be applied to the generated and fully Geant4 simulated events used in analysis without a special GENIE sample. For some limited uses, it could be cast as a 1D $Q^2$ weight without much trouble. This procedure is a suitable starting point for NOvA and DUNE where the energy dependence is modest, but probably not adequate for T2K or MicroBooNE.

  11. A prioritization of generic safety issues. Supplement 19, Revision insertion instructions

    International Nuclear Information System (INIS)

    1995-11-01

    The report presents the safety priority ranking for generic safety issues related to nuclear power plants. The purpose of these rankings is to assist in the timely and efficient allocation of NRC resources for the resolution of those safety issues that have a significant potential for reducing risk. The safety priority rankings are HIGH, MEDIUM, LOW, and DROP, and have been assigned on the basis of risk significance estimates, the ratio of risk to costs and other impacts estimated to result if resolution of the safety issues were implemented, and the consideration of uncertainties and other quantitative or qualitative factors. To the extent practical, estimates are quantitative. This document provides revisions and amendments to the report

  12. A prioritization of generic safety issues. Supplement 19, Revision insertion instructions

    Energy Technology Data Exchange (ETDEWEB)

    None

    1995-11-01

    The report presents the safety priority ranking for generic safety issues related to nuclear power plants. The purpose of these rankings is to assist in the timely and efficient allocation of NRC resources for the resolution of those safety issues that have a significant potential for reducing risk. The safety priority rankings are HIGH, MEDIUM, LOW, and DROP, and have been assigned on the basis of risk significance estimates, the ratio of risk to costs and other impacts estimated to result if resolution of the safety issues were implemented, and the consideration of uncertainties and other quantitative or qualitative factors. To the extent practical, estimates are quantitative. This document provides revisions and amendments to the report.

  13. Cost-effectiveness analysis of implementing an antimicrobial stewardship program in critical care units.

    Science.gov (United States)

    Ruiz-Ramos, Jesus; Frasquet, Juan; Romá, Eva; Poveda-Andres, Jose Luis; Salavert-Leti, Miguel; Castellanos, Alvaro; Ramirez, Paula

    2017-06-01

    To evaluate the cost-effectiveness of antimicrobial stewardship (AS) program implementation focused on critical care units based on assumptions for the Spanish setting. A decision model comparing costs and outcomes of sepsis, community-acquired pneumonia, and nosocomial infections (including catheter-related bacteremia, urinary tract infection, and ventilator-associated pneumonia) in critical care units with or without an AS was designed. Model variables and costs, along with their distributions, were obtained from the literature. The study was performed from the Spanish National Health System (NHS) perspective, including only direct costs. The Incremental Cost-Effectiveness Ratio (ICER) was analysed regarding the ability of the program to reduce multi-drug resistant bacteria. Uncertainty in ICERs was evaluated with probabilistic sensitivity analyses. In the short-term, implementing an AS reduces the consumption of antimicrobials with a net benefit of €71,738. In the long-term, the maintenance of the program involves an additional cost to the system of €107,569. Cost per avoided resistance was €7,342, and cost-per-life-years gained (LYG) was €9,788. Results from the probabilistic sensitivity analysis showed that there was a more than 90% likelihood that an AS would be cost-effective at a level of €8,000 per LYG. Wide variability of economic results obtained from the implementation of this type of AS program and short information on their impact on patient evolution and any resistance avoided. Implementing an AS focusing on critical care patients is a long-term cost-effective tool. Implementation costs are amortized by reducing antimicrobial consumption to prevent infection by multidrug-resistant pathogens.

  14. An Exact Soultion for the Investment and Market Value of a Firm Facing Uncertainty, Adjustment Costs, and Irreversibility

    OpenAIRE

    Andrew B. Abel; Janice C. Eberly

    1993-01-01

    This paper derives closed-form solutions for the investment and market value, under uncertainty, of competitive firms with constant returns to scale production and convex costs of adjustment. Solutions are derived for the case of irreversible investment as well as for reversible investment. Optimal investment is a non-decreasing function of q, the shadow value of capital. The conditions of optimality imply that q cannot contain a bubble; thus, optimal investment depends only on fundamentals. ...

  15. Vertical Cost-Information Sharing in a Food Supply Chain with Multiple Unreliable Suppliers and Two Manufacturers

    Directory of Open Access Journals (Sweden)

    Junjian Wu

    2017-01-01

    Full Text Available This paper considers a food supply chain where multiple suppliers provide completely substitutable food products to two manufacturers. Meanwhile, the suppliers face yield uncertainty and the manufacturers face uncertain production costs that are private information. While the suppliers compete on price, the manufacturers compete on quantity. We build a stylized multistage game theoretic model to analyze the issue of vertical cost-information sharing (VCIS within the supply chain by considering key parameters, including the level of yield uncertainty, two manufacturers’ cost correlation, the correlated coefficient of suppliers’ yield processes, and the number of suppliers. We study the suppliers’ optimal wholesale price and the manufacturers’ optimal order quantities under different VCIS strategies. Finally, through numerical analyses, we examine how key parameters affect the value of VCIS to each supplier and each manufacturer, respectively. We found that the manufacturers are willing to share cost information with suppliers only when the two manufacturers’ cost correlation is less than a threshold. While a high correlated coefficient of suppliers’ yield processes and a large number of suppliers promote complete information sharing, a high level of yield uncertainty hinders complete information sharing. All these findings have important implications to industry practices.

  16. Cost effectiveness and value of information analyses of islet cell transplantation in the management of 'unstable' type 1 diabetes mellitus.

    Science.gov (United States)

    Wallner, Klemens; Shapiro, A M James; Senior, Peter A; McCabe, Christopher

    2016-04-09

    Islet cell transplantation is a method to stabilize type 1 diabetes patients with hypoglycemia unawareness and unstable blood glucose levels by reducing insulin dependency and protecting against severe hypoglycemia through restoring endogenous insulin secretion. This study analyses the current cost-effectiveness of this technology and estimates the value of further research to reduce uncertainty around cost-effectiveness. We performed a cost-utility analysis using a Markov cohort model with a mean patient age of 49 to simulate costs and health outcomes over a life-time horizon. Our analysis used intensive insulin therapy (IIT) as comparator and took the provincial healthcare provider perspective. Cost and effectiveness data for up to four transplantations per patient came from the University of Alberta hospital. Costs are expressed in 2012 Canadian dollars and effectiveness in quality-adjusted life-years (QALYs) and life years. To characterize the uncertainty around expected outcomes, we carried out a probabilistic sensitivity analysis within the Bayesian decision-analytic framework. We performed a value-of-information analysis to identify priority areas for future research under various scenarios. We applied a structural sensitivity analysis to assess the dependence of outcomes on model characteristics. Compared to IIT, islet cell transplantation using non-generic (generic) immunosuppression had additional costs of $150,006 ($112,023) per additional QALY, an average gain of 3.3 life years, and a probability of being cost-effective of 0.5 % (28.3 %) at a willingness-to-pay threshold of $100,000 per QALY. At this threshold the non-generic technology has an expected value of perfect information (EVPI) of $260,744 for Alberta. This increases substantially in cost-reduction scenarios. The research areas with the highest partial EVPI are costs, followed by natural history, and effectiveness and safety. Current transplantation technology provides substantial

  17. Effectiveness of the food recovery at the retailing stage under shelf life uncertainty: An application to Italian food chains

    International Nuclear Information System (INIS)

    Muriana, Cinzia

    2015-01-01

    Highlights: • The food recovery is seen as suitable way to manage food near to its expiry date. • The variability of the products shelf life must be taken into account. • The paper addresses the mathematic modeling of the profit related to food recovery. • The optimal time to withdraw the products is determinant for food recovery. - Abstract: Food losses represent a significant issue affecting food supply chains. The possibility of recovering such products can be seen as an effective way to reduce such a phenomenon, improve supply chain performances and ameliorate the conditions of undernourished people. The topic has been already investigated by a previous paper enforcing the hypothesis of deterministic and constant Shelf Life (SL) of products. However, such a model cannot be properly extended to products affected by uncertainties of the SL as it does not take into account the deterioration costs and loss of profits due to the overcoming of the SL within the cycle time. Thus the present paper presents an extension of the previous one under stochastic conditions of the food quality. Differently from the previous publication, this work represents a general model applicable to all supply chains, especially to those managing fresh products characterized by uncertain SL such as fruits and vegetables. The deterioration costs and loss of profits are included in the model and the optimal time at which to withdraw the products from the shelves as well as the quantities to be shipped at each alternative destination have been determined. A comparison of the proposed model with that reported in the previous publication has been carried out in order to underline the impact of the SL variability on the optimality conditions. The results show that the food recovery strategy in the presence of uncertainty of the food quality is rewarding, even if the optimal profit is lower than that of the deterministic case

  18. Effectiveness of the food recovery at the retailing stage under shelf life uncertainty: An application to Italian food chains

    Energy Technology Data Exchange (ETDEWEB)

    Muriana, Cinzia, E-mail: cinzia.muriana@unipa.it

    2015-07-15

    Highlights: • The food recovery is seen as suitable way to manage food near to its expiry date. • The variability of the products shelf life must be taken into account. • The paper addresses the mathematic modeling of the profit related to food recovery. • The optimal time to withdraw the products is determinant for food recovery. - Abstract: Food losses represent a significant issue affecting food supply chains. The possibility of recovering such products can be seen as an effective way to reduce such a phenomenon, improve supply chain performances and ameliorate the conditions of undernourished people. The topic has been already investigated by a previous paper enforcing the hypothesis of deterministic and constant Shelf Life (SL) of products. However, such a model cannot be properly extended to products affected by uncertainties of the SL as it does not take into account the deterioration costs and loss of profits due to the overcoming of the SL within the cycle time. Thus the present paper presents an extension of the previous one under stochastic conditions of the food quality. Differently from the previous publication, this work represents a general model applicable to all supply chains, especially to those managing fresh products characterized by uncertain SL such as fruits and vegetables. The deterioration costs and loss of profits are included in the model and the optimal time at which to withdraw the products from the shelves as well as the quantities to be shipped at each alternative destination have been determined. A comparison of the proposed model with that reported in the previous publication has been carried out in order to underline the impact of the SL variability on the optimality conditions. The results show that the food recovery strategy in the presence of uncertainty of the food quality is rewarding, even if the optimal profit is lower than that of the deterministic case.

  19. Uncertainty Analyses and Strategy

    International Nuclear Information System (INIS)

    Kevin Coppersmith

    2001-01-01

    The DOE identified a variety of uncertainties, arising from different sources, during its assessment of the performance of a potential geologic repository at the Yucca Mountain site. In general, the number and detail of process models developed for the Yucca Mountain site, and the complex coupling among those models, make the direct incorporation of all uncertainties difficult. The DOE has addressed these issues in a number of ways using an approach to uncertainties that is focused on producing a defensible evaluation of the performance of a potential repository. The treatment of uncertainties oriented toward defensible assessments has led to analyses and models with so-called ''conservative'' assumptions and parameter bounds, where conservative implies lower performance than might be demonstrated with a more realistic representation. The varying maturity of the analyses and models, and uneven level of data availability, result in total system level analyses with a mix of realistic and conservative estimates (for both probabilistic representations and single values). That is, some inputs have realistically represented uncertainties, and others are conservatively estimated or bounded. However, this approach is consistent with the ''reasonable assurance'' approach to compliance demonstration, which was called for in the U.S. Nuclear Regulatory Commission's (NRC) proposed 10 CFR Part 63 regulation (64 FR 8640 [DIRS 101680]). A risk analysis that includes conservatism in the inputs will result in conservative risk estimates. Therefore, the approach taken for the Total System Performance Assessment for the Site Recommendation (TSPA-SR) provides a reasonable representation of processes and conservatism for purposes of site recommendation. However, mixing unknown degrees of conservatism in models and parameter representations reduces the transparency of the analysis and makes the development of coherent and consistent probability statements about projected repository

  20. Review of monitoring uncertainty requirements in the CDM

    International Nuclear Information System (INIS)

    Shishlov, Igor; Bellassen, Valentin

    2014-10-01

    In order to ensure the environmental integrity of carbon offset projects, emission reductions certified under the Clean Development Mechanism (CDM) have to be 'real, measurable and additional', which is ensured through the monitoring, reporting and verification (MRV) process. MRV, however, comes at a cost that ranges from several cents to EUR1.20 and above per ton of CO 2 e depending on the project type. This article analyzes monitoring uncertainty requirements for carbon offset projects with a particular focus on the trade-off between monitoring stringency and cost. To this end, we review existing literature, scrutinize both overarching monitoring guidelines and the 10 most-used methodologies, and finally we analyze four case studies. We find that there is indeed a natural trade-off between the stringency and the cost of monitoring, which if not addressed properly may become a major barrier for the implementation of offset projects in some sectors. We demonstrate that this trade-off has not been systematically addressed in the overarching CDM guidelines and that there are only limited incentives to reduce monitoring uncertainty. Some methodologies and calculation tools as well as some other offset standards, however, do incorporate provisions for a trade-off between monitoring costs and stringency. These provisions may take the form of discounting emissions reductions based on the level of monitoring uncertainty - or more implicitly through allowing a project developer to choose between monitoring a given parameter and using a conservative default value. Our findings support the introduction of an uncertainty standard under the CDM for more comprehensive, yet cost-efficient, accounting for monitoring uncertainty in carbon offset projects. (authors)

  1. Cost-Effectiveness of Surgery, Stereotactic Body Radiation Therapy, and Systemic Therapy for Pulmonary Oligometastases

    Energy Technology Data Exchange (ETDEWEB)

    Lester-Coll, Nataniel H., E-mail: nataniel.lester-coll@yale.edu [Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, Connecticut (United States); Rutter, Charles E.; Bledsoe, Trevor J. [Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, Connecticut (United States); Goldberg, Sarah B. [Department of Medicine (Medical Oncology), Yale University School of Medicine, New Haven, Connecticut (United States); Decker, Roy H.; Yu, James B. [Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, Connecticut (United States)

    2016-06-01

    Introduction: Pulmonary oligometastases have conventionally been managed with surgery and/or systemic therapy. However, given concerns about the high cost of systemic therapy and improvements in local treatment of metastatic cancer, the optimal cost-effective management of these patients is unclear. Therefore, we sought to assess the cost-effectiveness of initial management strategies for pulmonary oligometastases. Methods and Materials: A cost-effectiveness analysis using a Markov modeling approach was used to compare average cumulative costs, quality adjusted life years (QALYs), and incremental cost-effectiveness ratios (ICERs) among 3 initial disease management strategies: video-assisted thoracic surgery (VATS) wedge resection, stereotactic body radiation therapy (SBRT), and systemic therapy among 5 different cohorts of patient disease: (1) melanoma; (2) non-small cell lung cancer adenocarcinoma without an EGFR mutation (NSCLC AC); (3) NSCLC with an EGFR mutation (NSCLC EGFRm AC); (4) NSCLC squamous cell carcinoma (NSCLC SCC); and (5) colon cancer. One-way sensitivity analyses and probabilistic sensitivity analyses were performed to analyze uncertainty with regard to model parameters. Results: In the base case, SBRT was cost effective for melanoma, with costs/net QALYs of $467,787/0.85. In patients with NSCLC, the most cost-effective strategies were SBRT for AC ($156,725/0.80), paclitaxel/carboplatin for SCC ($123,799/0.48), and erlotinib for EGFRm AC ($147,091/1.90). Stereotactic body radiation therapy was marginally cost-effective for EGFRm AC compared to erlotinib with an incremental cost-effectiveness ratio of $126,303/QALY. For colon cancer, VATS wedge resection ($147,730/2.14) was the most cost-effective strategy. Variables with the greatest influence in the model were erlotinib-associated progression-free survival (EGFRm AC), toxicity (EGFRm AC), cost of SBRT (NSCLC SCC), and patient utilities (all histologies). Conclusions: Video-assisted thoracic

  2. The Uncertainty Test for the MAAP Computer Code

    International Nuclear Information System (INIS)

    Park, S. H.; Song, Y. M.; Park, S. Y.; Ahn, K. I.; Kim, K. R.; Lee, Y. J.

    2008-01-01

    After the Three Mile Island Unit 2 (TMI-2) and Chernobyl accidents, safety issues for a severe accident are treated in various aspects. Major issues in our research part include a level 2 PSA. The difficulty in expanding the level 2 PSA as a risk information activity is the uncertainty. In former days, it attached a weight to improve the quality in a internal accident PSA, but the effort is insufficient for decrease the phenomenon uncertainty in the level 2 PSA. In our country, the uncertainty degree is high in the case of a level 2 PSA model, and it is necessary to secure a model to decrease the uncertainty. We have not yet experienced the uncertainty assessment technology, the assessment system itself depends on advanced nations. In advanced nations, the severe accident simulator is implemented in the hardware level. But in our case, basic function in a software level can be implemented. In these circumstance at home and abroad, similar instances are surveyed such as UQM and MELCOR. Referred to these instances, SAUNA (Severe Accident UNcertainty Analysis) system is being developed in our project to assess and decrease the uncertainty in a level 2 PSA. It selects the MAAP code to analyze the uncertainty in a severe accident

  3. Contingency Cost estimation for Research reactor Decommissioning

    International Nuclear Information System (INIS)

    Jin, Hyung Gon; Hong, Yun Jeong

    2016-01-01

    There are many types of cost items in decommissioning cost estimation, however, contingencies are for unforeseen elements of cost within the defined project scope. Regulatory body wants to reasonable quantification for this issue. Many countries have adopted the breakdown of activity dependent and period-dependent costs to structure their estimates. Period-dependent costs could be broken down into defined time frames to reduce overall uncertainties. Several countries apply this notion by having different contingency factors for different phases of the project. This study is a compilation of contingency cost of research reactor and for each country. Simulation techniques using TRIM, MATLAB, and PSpice can be useful tools for designing detector channels. Thus far TRIM, MATLAB and PSpice have been used to calculate the detector current output pulse for SiC semiconductor detectors and to model the pulses that propagate through potential detector channels. This model is useful for optimizing the detector and the resolution for application to neutron monitoring in the Generation IV power reactors

  4. Contingency Cost estimation for Research reactor Decommissioning

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Hyung Gon; Hong, Yun Jeong [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    There are many types of cost items in decommissioning cost estimation, however, contingencies are for unforeseen elements of cost within the defined project scope. Regulatory body wants to reasonable quantification for this issue. Many countries have adopted the breakdown of activity dependent and period-dependent costs to structure their estimates. Period-dependent costs could be broken down into defined time frames to reduce overall uncertainties. Several countries apply this notion by having different contingency factors for different phases of the project. This study is a compilation of contingency cost of research reactor and for each country. Simulation techniques using TRIM, MATLAB, and PSpice can be useful tools for designing detector channels. Thus far TRIM, MATLAB and PSpice have been used to calculate the detector current output pulse for SiC semiconductor detectors and to model the pulses that propagate through potential detector channels. This model is useful for optimizing the detector and the resolution for application to neutron monitoring in the Generation IV power reactors.

  5. Uncertainty and validation. Effect of user interpretation on uncertainty estimates

    International Nuclear Information System (INIS)

    Kirchner, G.; Peterson, R.

    1996-11-01

    dependent behaviour of a model endpoint may be disguised as an accurate time integrated prediction when compared to the time-integrated observation. Agreement of predictions with observed concentrations in milk was often the result of compensatory errors. Although the effect of the user's assumptions on uncertainties was expected to be important, the wide variability of the predictions came as a surprise. A recommendation for assessments would be that at least two users, perhaps even with the same model, should calculate predictions before any decisions are made. Choices of parameter values and other assumptions should be made through a process of expert elicitation

  6. Uncertainty and validation. Effect of user interpretation on uncertainty estimates

    Energy Technology Data Exchange (ETDEWEB)

    Kirchner, G. [Univ. of Bremen (Germany); Peterson, R. [AECL, Chalk River, ON (Canada)] [and others

    1996-11-01

    time dependent behaviour of a model endpoint may be disguised as an accurate time integrated prediction when compared to the time-integrated observation. Agreement of predictions with observed concentrations in milk was often the result of compensatory errors. Although the effect of the user's assumptions on uncertainties was expected to be important, the wide variability of the predictions came as a surprise. A recommendation for assessments would be that at least two users, perhaps even with the same model, should calculate predictions before any decisions are made. Choices of parameter values and other assumptions should be made through a process of expert elicitation.

  7. Econometric modeling of health care costs and expenditures: a survey of analytical issues and related policy considerations.

    Science.gov (United States)

    Mullahy, John

    2009-07-01

    Econometric modeling of healthcare costs and expenditures has become an important component of decision-making across a wide array of real-world settings. The objective of this article is to provide a brief summary of important conceptual and analytical issues involved in econometric healthcare cost modeling. To this end, the article explores: outcome measures typically analyzed in such work; the decision maker's perspective in econometric cost modeling exercises; specific analytical issues in econometric model specification; statistical goodness-of-fit testing; empirical implications of "upper tail" (or "high cost") phenomena; and issues relating to the reporting of findings. Some of the concepts explored here are illustrated in light of samples drawn from the 2005 Medical Expenditure Panel Survey and the 2005 Nationwide Inpatient Sample. Analysts of healthcare cost data have at their disposal an increasingly sophisticated tool kit for analyzing such data that can in principle and in fact yield increasingly interesting insights into data structures. Yet for such analyses to usefully inform policy decisions, the manner in which such studies are designed, undertaken, and reported must accommodate considerations relevant to the decision-making community. The article concludes with some preliminary thoughts on how such bridges might be constructed.

  8. Can agent based models effectively reduce fisheries management implementation uncertainty?

    Science.gov (United States)

    Drexler, M.

    2016-02-01

    Uncertainty is an inherent feature of fisheries management. Implementation uncertainty remains a challenge to quantify often due to unintended responses of users to management interventions. This problem will continue to plague both single species and ecosystem based fisheries management advice unless the mechanisms driving these behaviors are properly understood. Equilibrium models, where each actor in the system is treated as uniform and predictable, are not well suited to forecast the unintended behaviors of individual fishers. Alternatively, agent based models (AMBs) can simulate the behaviors of each individual actor driven by differing incentives and constraints. This study evaluated the feasibility of using AMBs to capture macro scale behaviors of the US West Coast Groundfish fleet. Agent behavior was specified at the vessel level. Agents made daily fishing decisions using knowledge of their own cost structure, catch history, and the histories of catch and quota markets. By adding only a relatively small number of incentives, the model was able to reproduce highly realistic macro patterns of expected outcomes in response to management policies (catch restrictions, MPAs, ITQs) while preserving vessel heterogeneity. These simulations indicate that agent based modeling approaches hold much promise for simulating fisher behaviors and reducing implementation uncertainty. Additional processes affecting behavior, informed by surveys, are continually being added to the fisher behavior model. Further coupling of the fisher behavior model to a spatial ecosystem model will provide a fully integrated social, ecological, and economic model capable of performing management strategy evaluations to properly consider implementation uncertainty in fisheries management.

  9. Remediation of the Faultless Underground Nuclear Test: Moving Forward in the Face of Model Uncertainty

    International Nuclear Information System (INIS)

    Chapman, J. B.; Pohlmann, K.; Pohll, G.; Hassan, A.; Sanders, P.; Sanchez, M.; Jaunarajs, S.

    2002-01-01

    The Faultless underground nuclear test, conducted in central Nevada, is the site of an ongoing environmental remediation effort that has successfully progressed through numerous technical challenges due to close cooperation between the U.S. Department of Energy, (DOE) National Nuclear Security Administration and the State of Nevada Division of Environmental Protection (NDEP). The challenges faced at this site are similar to those of many other sites of groundwater contamination: substantial uncertainties due to the relative lack of data from a highly heterogeneous subsurface environment. Knowing when, where, and how to devote the often enormous resources needed to collect new data is a common problem, and one that can cause remediators and regulators to disagree and stall progress toward closing sites. For Faultless, a variety of numerical modeling techniques and statistical tools are used to provide the information needed for DOE and NDEP to confidently move forward along the remediation path to site closure. A general framework for remediation was established in an agreement and consent order between DOE and the State of Nevada that recognized that no cost-effective technology currently exists to remove the source of contaminants in nuclear cavities. Rather, the emphasis of the corrective action is on identifying the impacted groundwater resource and ensuring protection of human health and the environment from the contamination through monitoring. As a result, groundwater flow and transport modeling is the linchpin in the remediation effort. An early issue was whether or not new site data should be collected via drilling and testing prior to modeling. After several iterations of the Corrective Action Investigation Plan, all parties agreed that sufficient data existed to support a flow and transport model for the site. Though several aspects of uncertainty were included in the subsequent modeling work, concerns remained regarding uncertainty in individual

  10. Population cost-effectiveness of the Triple P parenting programme for the treatment of conduct disorder: an economic modelling study.

    Science.gov (United States)

    Sampaio, Filipa; Barendregt, Jan J; Feldman, Inna; Lee, Yong Yi; Sawyer, Michael G; Dadds, Mark R; Scott, James G; Mihalopoulos, Cathrine

    2017-12-29

    Parenting programmes are the recommended treatments of conduct disorders (CD) in children, but little is known about their longer term cost-effectiveness. This study aimed to evaluate the population cost-effectiveness of one of the most researched evidence-based parenting programmes, the Triple P-Positive Parenting Programme, delivered in a group and individual format, for the treatment of CD in children. A population-based multiple cohort decision analytic model was developed to estimate the cost per disability-adjusted life year (DALY) averted of Triple P compared with a 'no intervention' scenario, using a health sector perspective. The model targeted a cohort of 5-9-year-old children with CD in Australia currently seeking treatment, and followed them until they reached adulthood (i.e., 18 years). Multivariate probabilistic and univariate sensitivity analyses were conducted to incorporate uncertainty in the model parameters. Triple P was cost-effective compared to no intervention at a threshold of AU$50,000 per DALY averted when delivered in a group format [incremental cost-effectiveness ratio (ICER) = $1013 per DALY averted; 95% uncertainty interval (UI) 471-1956] and in an individual format (ICER = $20,498 per DALY averted; 95% UI 11,146-39,470). Evidence-based parenting programmes, such as the Triple P, for the treatment of CD among children appear to represent good value for money, when delivered in a group or an individual face-to-face format, with the group format being the most cost-effective option. The current model can be used for economic evaluations of other interventions targeting CD and in other settings.

  11. The cost-effectiveness of nonoperative management versus laparoscopic appendectomy for the treatment of acute, uncomplicated appendicitis in children.

    Science.gov (United States)

    Wu, James X; Sacks, Greg D; Dawes, Aaron J; DeUgarte, Daniel; Lee, Steven L

    2017-07-01

    Several studies have demonstrated the safety and short-term success of nonoperative management in children with acute, uncomplicated appendicitis. Nonoperative management spares the patients and their family the upfront cost and discomfort of surgery, but also risks recurrent appendicitis. Using decision-tree software, we evaluated the cost-effectiveness of nonoperative management versus routine laparoscopic appendectomy. Model variables were abstracted from a review of the literature, Healthcare Cost and Utilization Project, and Medicare Physician Fee schedule. Model uncertainty was assessed using both one-way and probabilistic sensitivity analyses. We used a $100,000 per quality adjusted life year (QALY) threshold for cost-effectiveness. Operative management cost $11,119 and yielded 23.56 quality-adjusted life months (QALMs). Nonoperative management cost $2277 less than operative management, but yielded 0.03 fewer QALMs. The incremental cost-to-effectiveness ratio of routine laparoscopic appendectomy was $910,800 per QALY gained. This greatly exceeds the $100,000/QALY threshold and was not cost-effective. One-way sensitivity analysis found that operative management would become cost-effective if the 1-year recurrence rate of acute appendicitis exceeded 39.8%. Probabilistic sensitivity analysis indicated that nonoperative management was cost-effective in 92% of simulations. Based on our model, nonoperative management is more cost-effective than routine laparoscopic appendectomy for children with acute, uncomplicated appendicitis. Cost-Effectiveness Study: Level II. Published by Elsevier Inc.

  12. Costs, health effects and cost-effectiveness of alcohol and tobacco control strategies in Estonia.

    NARCIS (Netherlands)

    Lai, T.; Habicht, J.; Reinap, M.; Chisholm, D.; Baltussen, R.M.P.M.

    2007-01-01

    OBJECTIVE: To assess the population-level costs, effects and cost-effectiveness of different alcohol and tobacco control strategies in Estonia. DESIGN: A WHO cost-effectiveness modelling framework was used to estimate the total costs and effects of interventions. Costs were assessed in Estonian

  13. Cost-effectiveness of alternative conservation strategies with application to the Pacific leatherback turtle.

    Science.gov (United States)

    Gjertsen, Heidi; Squires, Dale; Dutton, Peter H; Eguchi, Tomoharu

    2014-02-01

    Although holistic conservation addressing all sources of mortality for endangered species or stocks is the preferred conservation strategy, limited budgets require a criterion to prioritize conservation investments. We compared the cost-effectiveness of nesting site and at-sea conservation strategies for Pacific leatherback turtles (Dermochelys coriacea). We sought to determine which conservation strategy or mix of strategies would produce the largest increase in population growth rate per dollar. Alternative strategies included protection of nesters and their eggs at nesting beaches in Indonesia, gear changes, effort restrictions, and caps on turtle takes in the Hawaiian (U.S.A.) longline swordfish fishery, and temporal and area closures in the California (U.S.A.) drift gill net fishery. We used a population model with a biological metric to measure the effects of conservation alternatives. We normalized all effects by cost to prioritize those strategies with the greatest biological effect relative to its economic cost. We used Monte Carlo simulation to address uncertainty in the main variables and to calculate probability distributions for cost-effectiveness measures. Nesting beach protection was the most cost-effective means of achieving increases in leatherback populations. This result creates the possibility of noncompensatory bycatch mitigation, where high-bycatch fisheries invest in protecting nesting beaches. An example of this practice is U.S. processors of longline tuna and California drift gill net fishers that tax themselves to finance low-cost nesting site protection. Under certain conditions, fisheries interventions, such as technologies that reduce leatherback bycatch without substantially decreasing target species catch, can be cost-effective. Reducing bycatch in coastal areas where bycatch is high, particularly adjacent to nesting beaches, may be cost-effective, particularly, if fisheries in the area are small and of little commercial value.

  14. Resistance Economics of Transgenic Crops under Uncertainty: A Real Option Approach

    NARCIS (Netherlands)

    Wesseler, J.H.H.

    2003-01-01

    The development of pest resistance is one of the many concerns about the long-term success of transgenic crops. This chapter discusses resistances as additional irreversible costs related to the release of transgenic crops. These irreversible costs, their uncertainty, and the uncertainty about

  15. Incremental Costs and Cost Effectiveness of Intensive Treatment in Individuals with Type 2 Diabetes Detected by Screening in the ADDITION-UK Trial: An Update with Empirical Trial-Based Cost Data.

    Science.gov (United States)

    Laxy, Michael; Wilson, Edward C F; Boothby, Clare E; Griffin, Simon J

    2017-12-01

    There is uncertainty about the cost effectiveness of early intensive treatment versus routine care in individuals with type 2 diabetes detected by screening. To derive a trial-informed estimate of the incremental costs of intensive treatment as delivered in the Anglo-Danish-Dutch Study of Intensive Treatment in People with Screen-Detected Diabetes in Primary Care-Europe (ADDITION) trial and to revisit the long-term cost-effectiveness analysis from the perspective of the UK National Health Service. We analyzed the electronic primary care records of a subsample of the ADDITION-Cambridge trial cohort (n = 173). Unit costs of used primary care services were taken from the published literature. Incremental annual costs of intensive treatment versus routine care in years 1 to 5 after diagnosis were calculated using multilevel generalized linear models. We revisited the long-term cost-utility analyses for the ADDITION-UK trial cohort and reported results for ADDITION-Cambridge using the UK Prospective Diabetes Study Outcomes Model and the trial-informed cost estimates according to a previously developed evaluation framework. Incremental annual costs of intensive treatment over years 1 to 5 averaged £29.10 (standard error = £33.00) for consultations with general practitioners and nurses and £54.60 (standard error = £28.50) for metabolic and cardioprotective medication. For ADDITION-UK, over the 10-, 20-, and 30-year time horizon, adjusted incremental quality-adjusted life-years (QALYs) were 0.014, 0.043, and 0.048, and adjusted incremental costs were £1,021, £1,217, and £1,311, resulting in incremental cost-effectiveness ratios of £71,232/QALY, £28,444/QALY, and £27,549/QALY, respectively. Respective incremental cost-effectiveness ratios for ADDITION-Cambridge were slightly higher. The incremental costs of intensive treatment as delivered in the ADDITION-Cambridge trial were lower than expected. Given UK willingness-to-pay thresholds in patients with screen

  16. Cost-effectiveness of a transitional pharmaceutical care program for patients discharged from the hospital.

    Directory of Open Access Journals (Sweden)

    Fatma Karapinar-Çarkıt

    Full Text Available To improve continuity of care at hospital admission and discharge and to decrease medication errors pharmaceutical care programs are developed. This study aims to determine the cost-effectiveness of the COACH program in comparison with usual care from a societal perspective.A controlled clinical trial was performed at the Internal Medicine department of a general teaching hospital. All admitted patients using at least one prescription drug were included. The COACH program consisted of medication reconciliation, patient counselling at discharge, and communication to healthcare providers in primary care. The primary outcome was the proportion of patients with an unplanned rehospitalisation within three months after discharge. Also, the number of quality-adjusted life-years (QALYs was assessed. Cost data were collected using cost diaries. Uncertainty surrounding cost differences and incremental cost-effectiveness ratios between the groups was estimated by bootstrapping.In the COACH program, 168 patients were included and in usual care 151 patients. There was no significant difference in the proportion of patients with unplanned rehospitalisations (mean difference 0.17%, 95% CI -8.85;8.51, and in QALYs (mean difference -0.0085, 95% CI -0.0170;0.0001. Total costs for the COACH program were non-significantly lower than usual care (-€1160, 95% CI -3168;847. Cost-effectiveness planes showed that the program was not cost-effective compared with usual care for unplanned rehospitalisations and QALYs gained.The COACH program was not cost-effective in comparison with usual care. Future studies should focus on high risk patients and include other outcomes (e.g. adverse drug events as this may increase the chances of a cost-effective intervention. Dutch trial register NTR1519.

  17. Uncertainty in the Real World

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 4; Issue 2. Uncertainty in the Real World - Fuzzy Sets. Satish Kumar. General Article Volume 4 Issue 2 February 1999 pp 37-47. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/004/02/0037-0047 ...

  18. Modelling the cost-effectiveness of impact-absorbing flooring in Swedish residential care facilities.

    Science.gov (United States)

    Ryen, Linda; Svensson, Mikael

    2016-06-01

    Fall-related injuries among the elderly, specifically hip fractures, cause significant morbidity and mortality as well as imposing a substantial financial cost on the health care system. Impact-absorbing flooring has been advocated as an effective method for preventing hip fractures resulting from falls. This study identifies the cost-effectiveness of impact-absorbing flooring compared to standard flooring in residential care facilities for the elderly in a Swedish setting. An incremental cost-effectiveness analysis was performed comparing impact-absorbing flooring to standard flooring using a Markov decision model. A societal perspective was adopted and incremental costs were compared to incremental gains in quality-adjusted life years (QALYs). Data on costs, probability transitions and health-related quality of life measures were retrieved from the published literature and from Swedish register data. Probabilistic sensitivity analysis was performed through a Monte Carlo simulation. The base-case analysis indicates that the impact-absorbing flooring reduces costs and increases QALYs. When allowing for uncertainty we find that 60% of the simulations indicate that impact-absorbing flooring is cost-saving compared to standard flooring and an additional 20% that it has a cost per QALY below a commonly used threshold value : Using a modelling approach, we find that impact-absorbing flooring is a dominant strategy at the societal level considering that it can save resources and improve health in a vulnerable population. © The Author 2015. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.

  19. Aleatoric and epistemic uncertainties in sampling based nuclear data uncertainty and sensitivity analyses

    International Nuclear Information System (INIS)

    Zwermann, W.; Krzykacz-Hausmann, B.; Gallner, L.; Klein, M.; Pautz, A.; Velkov, K.

    2012-01-01

    Sampling based uncertainty and sensitivity analyses due to epistemic input uncertainties, i.e. to an incomplete knowledge of uncertain input parameters, can be performed with arbitrary application programs to solve the physical problem under consideration. For the description of steady-state particle transport, direct simulations of the microscopic processes with Monte Carlo codes are often used. This introduces an additional source of uncertainty, the aleatoric sampling uncertainty, which is due to the randomness of the simulation process performed by sampling, and which adds to the total combined output sampling uncertainty. So far, this aleatoric part of uncertainty is minimized by running a sufficiently large number of Monte Carlo histories for each sample calculation, thus making its impact negligible as compared to the impact from sampling the epistemic uncertainties. Obviously, this process may cause high computational costs. The present paper shows that in many applications reliable epistemic uncertainty results can also be obtained with substantially lower computational effort by performing and analyzing two appropriately generated series of samples with much smaller number of Monte Carlo histories each. The method is applied along with the nuclear data uncertainty and sensitivity code package XSUSA in combination with the Monte Carlo transport code KENO-Va to various critical assemblies and a full scale reactor calculation. It is shown that the proposed method yields output uncertainties and sensitivities equivalent to the traditional approach, with a high reduction of computing time by factors of the magnitude of 100. (authors)

  20. Integration of renewable generation uncertainties into stochastic unit commitment considering reserve and risk: A comparative study

    International Nuclear Information System (INIS)

    Quan, Hao; Srinivasan, Dipti; Khosravi, Abbas

    2016-01-01

    The uncertainties of renewable energy have brought great challenges to power system commitment, dispatches and reserve requirement. This paper presents a comparative study on integration of renewable generation uncertainties into SCUC (stochastic security-constrained unit commitment) considering reserve and risk. Renewable forecast uncertainties are captured by a list of PIs (prediction intervals). A new scenario generation method is proposed to generate scenarios from these PIs. Different system uncertainties are considered as scenarios in the stochastic SCUC problem formulation. Two comparative simulations with single (E1: wind only) and multiple sources of uncertainty (E2: load, wind, solar and generation outages) are investigated. Five deterministic and four stochastic case studies are performed. Different generation costs, reserve strategies and associated risks are compared under various scenarios. Demonstrated results indicate the overall costs of E2 is lower than E1 due to penetration of solar power and the associated risk in deterministic cases of E2 is higher than E1. It implies the superimposed effect of uncertainties during uncertainty integration. The results also demonstrate that power systems run a higher level of risk during peak load hours, and that stochastic models are more robust than deterministic ones. - Highlights: • An extensive comparative study for renewable integration is presented. • A novel scenario generation method is proposed. • Wind and solar uncertainties are represented by a list of prediction intervals. • Unit commitment and dispatch costs are discussed considering reserve and risk.

  1. Long-term effectiveness and cost-effectiveness of smoking cessation interventions in patients with COPD.

    Science.gov (United States)

    Hoogendoorn, Martine; Feenstra, Talitha L; Hoogenveen, Rudolf T; Rutten-van Mölken, Maureen P M H

    2010-08-01

    The aim of this study was to estimate the long-term (cost-) effectiveness of smoking cessation interventions for patients with chronic obstructive pulmonary disease (COPD). A systematic review was performed of randomised controlled trials on smoking cessation interventions in patients with COPD reporting 12-month biochemical validated abstinence rates. The different interventions were grouped into four categories: usual care, minimal counselling, intensive counselling and intensive counselling + pharmacotherapy ('pharmacotherapy'). For each category the average 12-month continuous abstinence rate and intervention costs were estimated. A dynamic population model for COPD was used to project the long-term (cost-) effectiveness (25 years) of 1-year implementation of the interventions for 50% of the patients with COPD who smoked compared with usual care. Uncertainty and one-way sensitivity analyses were performed for variations in the calculation of the abstinence rates, the type of projection, intervention costs and discount rates. Nine studies were selected. The average 12-month continuous abstinence rates were estimated to be 1.4% for usual care, 2.6% for minimal counselling, 6.0% for intensive counselling and 12.3% for pharmacotherapy. Compared with usual care, the costs per quality-adjusted life year (QALY) gained for minimal counselling, intensive counselling and pharmacotherapy were euro 16 900, euro 8200 and euro 2400, respectively. The results were most sensitive to variations in the estimation of the abstinence rates and discount rates. Compared with usual care, intensive counselling and pharmacotherapy resulted in low costs per QALY gained with ratios comparable to results for smoking cessation in the general population. Compared with intensive counselling, pharmacotherapy was cost saving and dominated the other interventions.

  2. Cost-effectiveness of insulin analogs from the perspective of the Brazilian public health system

    Directory of Open Access Journals (Sweden)

    Maurílio de Souza Cazarim

    2017-11-01

    Full Text Available ABSTRACT Human insulin is provided by the Brazilian Public Health System (BPHS for the treatment of diabetes, however, legal proceedings to acquire insulin analogs have burdened the BPHS health system. The aim of this study was to perform a cost-effectiveness analysis to compare insulin analogs and human insulins. This is a pharmacoeconomic study of cost-effectiveness. The direct medical cost related to insulin extracted from the Ministry of Health drug price list was considered. The clinical results, i.e. reduction in glycated hemoglobin (HbA1c, were extracted by meta-analysis. Different scenarios were structured to measure the uncertainties regarding the costs and reduction in HbA1c. Decision tree was developed for sensitivity of Incremental Cost Effectiveness Ratio (ICER. A total of fifteen scenarios were structured. Given the best-case scenario for the insulin analogs, the insulins aspart, lispro, glargine and detemir showed an ICER of R$ 1,768.59; R$ 3,308.54; R$ 11,718.75 and R$ 2,685.22, respectively. In all scenarios in which the minimum effectiveness was proposed, lispro, glargine and detemir were dominant strategies. Sensitivity analysis showed that the aspart had R$ 3,066.98 [95 % CI: 2339.22; 4418.53] and detemir had R$ 6,163.97 [95% CI: 3919.29; 11401.57] for incremental costs. We concluded there was evidence that the insulin aspart is the most cost-effective.

  3. Preoperative paravertebral blocks for the management of acute pain following mastectomy: a cost-effectiveness analysis.

    Science.gov (United States)

    Offodile, Anaeze C; Sheckter, Clifford C; Tucker, Austin; Watzker, Anna; Ottino, Kevin; Zammert, Martin; Padula, William V

    2017-10-01

    Preoperative paravertebral blocks (PPVBs) are routinely used for treating post-mastectomy pain, yet uncertainties remain about the cost-effectiveness of this modality. We aim to evaluate the cost-effectiveness of PPVBs at common willingness-to-pay (WTP) thresholds. A decision analytic model compared two strategies: general anesthesia (GA) alone versus GA with multilevel PPVB. For the GA plus PPVB limb, patients were subjected to successful block placement versus varying severity of complications based on literature-derived probabilities. The need for rescue pain medication was the terminal node for all postoperative scenarios. Patient-reported pain scores sourced from published meta-analyses measured treatment effectiveness. Costing was derived from wholesale acquisition costs, the Medicare fee schedule, and publicly available hospital charge masters. Charges were converted to costs and adjusted for 2016 US dollars. A commercial payer perspective was adopted. Incremental cost-effectiveness ratios (ICERs) were evaluated against WTP thresholds of $500 and $50,000 for postoperative pain control. The ICER for preoperative paravertebral blocks was $154.49 per point reduction in pain score. 15% variation in inpatient costs resulted in ICER values ranging from $124.40-$180.66 per pain point score reduction. Altering the probability of block success by 5% generated ICER values of $144.71-$163.81 per pain score reduction. Probabilistic sensitivity analysis yielded cost-effective trials 69.43% of the time at $500 WTP thresholds. Over a broad range of probabilities, PPVB in mastectomy reduces postoperative pain at an acceptable incremental cost compared to GA. Commercial payers should be persuaded to reimburse this technique based on convincing evidence of cost-effectiveness.

  4. Cost-effectiveness analysis of cochlear dose reduction by proton beam therapy for medulloblastoma in childhood

    International Nuclear Information System (INIS)

    Hirano, Emi; Kawabuchi, Koichi; Fuji, Hiroshi; Onoe, Tsuyoshi; Kumar, Vinay; Shirato, Hiroki

    2014-01-01

    The aim of this study is to evaluate the cost-effectiveness of proton beam therapy with cochlear dose reduction compared with conventional X-ray radiotherapy for medulloblastoma in childhood. We developed a Markov model to describe health states of 6-year-old children with medulloblastoma after treatment with proton or X-ray radiotherapy. The risks of hearing loss were calculated on cochlear dose for each treatment. Three types of health-related quality of life (HRQOL) of EQ-5D, HUI3 and SF-6D were used for estimation of quality-adjusted life years (QALYs). The incremental cost-effectiveness ratio (ICER) for proton beam therapy compared with X-ray radiotherapy was calculated for each HRQOL. Sensitivity analyses were performed to model uncertainty in these parameters. The ICER for EQ-5D, HUI3 and SF-6D were $21 716/QALY, $11 773/QALY, and $20 150/QALY, respectively. One-way sensitivity analyses found that the results were sensitive to discount rate, the risk of hearing loss after proton therapy, and costs of proton irradiation. Cost-effectiveness acceptability curve analysis revealed a 99% probability of proton therapy being cost effective at a societal willingness-to-pay value. Proton beam therapy with cochlear dose reduction improves health outcomes at a cost that is within the acceptable cost-effectiveness range from the payer's standpoint. (author)

  5. A decision model for cost effective design of biomass based green energy supply chains.

    Science.gov (United States)

    Yılmaz Balaman, Şebnem; Selim, Hasan

    2015-09-01

    The core driver of this study is to deal with the design of anaerobic digestion based biomass to energy supply chains in a cost effective manner. In this concern, a decision model is developed. The model is based on fuzzy multi objective decision making in order to simultaneously optimize multiple economic objectives and tackle the inherent uncertainties in the parameters and decision makers' aspiration levels for the goals. The viability of the decision model is explored with computational experiments on a real-world biomass to energy supply chain and further analyses are performed to observe the effects of different conditions. To this aim, scenario analyses are conducted to investigate the effects of energy crop utilization and operational costs on supply chain structure and performance measures. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Decision making under uncertainty: a quasimetric approach.

    Directory of Open Access Journals (Sweden)

    Steve N'Guyen

    Full Text Available We propose a new approach for solving a class of discrete decision making problems under uncertainty with positive cost. This issue concerns multiple and diverse fields such as engineering, economics, artificial intelligence, cognitive science and many others. Basically, an agent has to choose a single or series of actions from a set of options, without knowing for sure their consequences. Schematically, two main approaches have been followed: either the agent learns which option is the correct one to choose in a given situation by trial and error, or the agent already has some knowledge on the possible consequences of his decisions; this knowledge being generally expressed as a conditional probability distribution. In the latter case, several optimal or suboptimal methods have been proposed to exploit this uncertain knowledge in various contexts. In this work, we propose following a different approach, based on the geometric intuition of distance. More precisely, we define a goal independent quasimetric structure on the state space, taking into account both cost function and transition probability. We then compare precision and computation time with classical approaches.

  7. Cost Analysis In A Multi-Mission Operations Environment

    Science.gov (United States)

    Newhouse, M.; Felton, L.; Bornas, N.; Botts, D.; Roth, K.; Ijames, G.; Montgomery, P.

    2014-01-01

    Spacecraft control centers have evolved from dedicated, single-mission or single missiontype support to multi-mission, service-oriented support for operating a variety of mission types. At the same time, available money for projects is shrinking and competition for new missions is increasing. These factors drive the need for an accurate and flexible model to support estimating service costs for new or extended missions; the cost model in turn drives the need for an accurate and efficient approach to service cost analysis. The National Aeronautics and Space Administration (NASA) Huntsville Operations Support Center (HOSC) at Marshall Space Flight Center (MSFC) provides operations services to a variety of customers around the world. HOSC customers range from launch vehicle test flights; to International Space Station (ISS) payloads; to small, short duration missions; and has included long duration flagship missions. The HOSC recently completed a detailed analysis of service costs as part of the development of a complete service cost model. The cost analysis process required the team to address a number of issues. One of the primary issues involves the difficulty of reverse engineering individual mission costs in a highly efficient multimission environment, along with a related issue of the value of detailed metrics or data to the cost model versus the cost of obtaining accurate data. Another concern is the difficulty of balancing costs between missions of different types and size and extrapolating costs to different mission types. The cost analysis also had to address issues relating to providing shared, cloud-like services in a government environment, and then assigning an uncertainty or risk factor to cost estimates that are based on current technology, but will be executed using future technology. Finally the cost analysis needed to consider how to validate the resulting cost models taking into account the non-homogeneous nature of the available cost data and the

  8. Personal Conflict Impairs Performance on an Unrelated Self-Control Task: Lingering Costs of Uncertainty and Conflict.

    Science.gov (United States)

    Alquist, Jessica L; Baumeister, Roy F; McGregor, Ian; Core, Tammy J; Benjamin, Ilil; Tice, Dianne M

    2018-01-01

    People have the ability to make important choices in their lives, but deliberating about these choices can have costs. The present study was designed to test the hypothesis that writing about conflicted personal goals and values (conflict condition) would impair self-control on an unrelated subsequent task as compared to writing about clear personal goals and values (clarity condition). Personal conflict activates the behavioral inhibition system (BIS; Hirsh, Mar, & Peterson, 2012), which may make it harder for participants to successfully execute self-control. In this large ( N =337), pre-registered study participants in the conflict condition performed worse on anagrams than participants in the clarity condition, and the effect of condition on anagram performance was mediated by a subjective uncertainty measure of BIS activation. This suggests that BIS activation leads to poor self-control. Moreover, given that conflict is inherent in the exercise of self-control, results point to BIS activation as a mechanism for why initial acts of self-control impair self-control on subsequent, unrelated tasks.

  9. The effect of an integrated education model on anxiety and uncertainty in patients undergoing cervical disc herniation surgery.

    Science.gov (United States)

    Chuang, Mei-Fang; Tung, Heng-Hsin; Clinciu, Daniel L; Huang, Jing-Shan; Iqbal, Usman; Chang, Chih-Ju; Su, I-Chang; Lai, Fu-Chih; Li, Yu-Chuan

    2016-09-01

    Educating patients about receiving surgical procedures is becoming an important issue, as it can reduce anxiety and uncertainty while helping to hasten decisions for undergoing time sensitive surgeries. We evaluated a new integrated education model for patients undergoing cervical disc herniation surgery using a quasi-experimental design. The participants were grouped into either the new integrated educational model (n = 32) or the standard group (n = 32) on the basis of their ward numbers assigned at admission. Anxiety, uncertainty, and patient satisfaction were measured before (pre-test) and after the educational intervention (post-test-1) and post-surgery (post-test-2) to assess the effectiveness of the model in this intervention. We found that the generalized estimating equation modeling demonstrated this new integrated education model was more effective than the conventional model in reducing patients' anxiety and uncertainty (p approach to individual health. This novel systemic educational model enhances patient's understanding of the medical condition and surgery while promoting patient-caregiver interaction for optimal patient health outcomes. We present a comprehensive and consistent platform for educational purposes in patients undergoing surgery as well as reducing the psychological burden from anxiety and uncertainty. Integrating medicine, nursing, and new technologies into an e-practice and e-learning platform offers the potential of easier understanding and usage. It could revolutionize patient education in the future. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  10. Uncertainties in human health risk assessment of environmental contaminants: A review and perspective.

    Science.gov (United States)

    Dong, Zhaomin; Liu, Yanju; Duan, Luchun; Bekele, Dawit; Naidu, Ravi

    2015-12-01

    Addressing uncertainties in human health risk assessment is a critical issue when evaluating the effects of contaminants on public health. A range of uncertainties exist through the source-to-outcome continuum, including exposure assessment, hazard and risk characterisation. While various strategies have been applied to characterising uncertainty, classical approaches largely rely on how to maximise the available resources. Expert judgement, defaults and tools for characterising quantitative uncertainty attempt to fill the gap between data and regulation requirements. The experiences of researching 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) illustrated uncertainty sources and how to maximise available information to determine uncertainties, and thereby provide an 'adequate' protection to contaminant exposure. As regulatory requirements and recurring issues increase, the assessment of complex scenarios involving a large number of chemicals requires more sophisticated tools. Recent advances in exposure and toxicology science provide a large data set for environmental contaminants and public health. In particular, biomonitoring information, in vitro data streams and computational toxicology are the crucial factors in the NexGen risk assessment, as well as uncertainties minimisation. Although in this review we cannot yet predict how the exposure science and modern toxicology will develop in the long-term, current techniques from emerging science can be integrated to improve decision-making. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Methodological challenges for the evaluation of clinical effectiveness in the context of accelerated regulatory approval: an overview.

    Science.gov (United States)

    Woolacott, Nerys; Corbett, Mark; Jones-Diette, Julie; Hodgson, Robert

    2017-10-01

    Regulatory authorities are approving innovative therapies with limited evidence. Although this level of data is sufficient for the regulator to establish an acceptable risk-benefit balance, it is problematic for downstream health technology assessment, where assessment of cost-effectiveness requires reliable estimates of effectiveness relative to existing clinical practice. Some key issues associated with a limited evidence base include using data, from nonrandomized studies, from small single-arm trials, or from single-center trials; and using surrogate end points. We examined these methodological challenges through a pragmatic review of the available literature. Methods to adjust nonrandomized studies for confounding are imperfect. The relative treatment effect generated from single-arm trials is uncertain and may be optimistic. Single-center trial results may not be generalizable. Surrogate end points, on average, overestimate treatment effects. Current methods for analyzing such data are limited, and effectiveness claims based on these suboptimal forms of evidence are likely to be subject to significant uncertainty. Assessments of cost-effectiveness, based on the modeling of such data, are likely to be subject to considerable uncertainty. This uncertainty must not be underestimated by decision makers: methods for its quantification are required and schemes to protect payers from the cost of uncertainty should be implemented. Crown Copyright © 2017. Published by Elsevier Inc. All rights reserved.

  12. Cost-effective mammography screening in Korea. High incidence of breast cancer in young women

    International Nuclear Information System (INIS)

    Lee, Soon-Young; Jeong, Seong-Hwa; Kim, Youn-Nam; Kim, Jinheum; Kang, Dae-Ryong; Kim, Hyeon-Chang; Nam, Chung-Mo

    2009-01-01

    The epidemiological characteristics of breast cancer in Korean women are different from the characteristics reported in Western women. The highest incidence rate occurs in Korean women in their 40s. The purpose of this study was to determine the most cost-effective screening interval and target age range for Korean women from the perspective of the national healthcare system. A stochastic model was used to simulate breast cancer screenings by varying both the screening intervals and the age ranges. The effectiveness of mammography screening was defined as the probability of detecting breast cancer in the preclinical state and the cost was based on the direct cost of mammography screening and the confirmative tests. The age-specific mean sojourn times and the sensitivity of the mammography were applied in the stochastic model. An optimal cost-effectiveness was determined by the incremental cost-effectiveness ratio and lifetime schedule sensitivity. Sensitivity analyses were undertaken to assess parameter uncertainty. The selected cost-effective strategies were: the current biennial mammography screenings for women who are at least 40 years old; biennial screening for women between the ages of 35 and 75 years; and a combination strategy consisting of biennial screening for women aged between 45 and 54 years, and 3-year interval screening for women aged between 40 and 44 years and 55 and 65 years. Further studies should follow to investigate the effectiveness of mammography screening in women younger than 40 years in Asia as well as in Korea. (author)

  13. Cost-effective degradation test plan for a nonlinear random-coefficients model

    International Nuclear Information System (INIS)

    Kim, Seong-Joon; Bae, Suk Joo

    2013-01-01

    The determination of requisite sample size and the inspection schedule considering both testing cost and accuracy has been an important issue in the degradation test. This paper proposes a cost-effective degradation test plan in the context of a nonlinear random-coefficients model, while meeting some precision constraints for failure-time distribution. We introduce a precision measure to quantify the information losses incurred by reducing testing resources. The precision measure is incorporated into time-varying cost functions to reflect real circumstances. We apply a hybrid genetic algorithm to general cost optimization problem with reasonable constraints on the level of testing precision in order to determine a cost-effective inspection scheme. The proposed method is applied to the degradation data of plasma display panels (PDPs) following a bi-exponential degradation model. Finally, sensitivity analysis via simulation is provided to evaluate the robustness of the proposed degradation test plan.

  14. Uncertainty in air quality observations using low-cost sensors

    Science.gov (United States)

    Castell, Nuria; Dauge, Franck R.; Dongol, Rozina; Vogt, Matthias; Schneider, Philipp

    2016-04-01

    due to changes in the environmental conditions. Currently there is a lack of testing to ensure adequate sensor performance prior to marketing such instruments. Even when manufacturers provide detailed specification sheets, there is little guarantee that the specifications can actually be met in real-world conditions. Data quality is a pertinent concern, especially when citizens are collecting and interpreting the data by themselves. Poor or unknown data quality can lead to incorrect or inappropriate decisions. We present the experiences gained within the EU project CITI-SENSE, where low-cost sensors are one of the tools employed to empower citizens in air quality issues.

  15. Decoherence effect on quantum-memory-assisted entropic uncertainty relations

    Science.gov (United States)

    Ming, Fei; Wang, Dong; Huang, Ai-Jun; Sun, Wen-Yang; Ye, Liu

    2018-01-01

    Uncertainty principle significantly provides a bound to predict precision of measurement with regard to any two incompatible observables, and thereby plays a nontrivial role in quantum precision measurement. In this work, we observe the dynamical features of the quantum-memory-assisted entropic uncertainty relations (EUR) for a pair of incompatible measurements in an open system characterized by local generalized amplitude damping (GAD) noises. Herein, we derive the dynamical evolution of the entropic uncertainty with respect to the measurement affecting by the canonical GAD noises when particle A is initially entangled with quantum memory B. Specifically, we examine the dynamics of EUR in the frame of three realistic scenarios: one case is that particle A is affected by environmental noise (GAD) while particle B as quantum memory is free from any noises, another case is that particle B is affected by the external noise while particle A is not, and the last case is that both of the particles suffer from the noises. By analytical methods, it turns out that the uncertainty is not full dependent of quantum correlation evolution of the composite system consisting of A and B, but the minimal conditional entropy of the measured subsystem. Furthermore, we present a possible physical interpretation for the behavior of the uncertainty evolution by means of the mixedness of the observed system; we argue that the uncertainty might be dramatically correlated with the systematic mixedness. Furthermore, we put forward a simple and effective strategy to reduce the measuring uncertainty of interest upon quantum partially collapsed measurement. Therefore, our explorations might offer an insight into the dynamics of the entropic uncertainty relation in a realistic system, and be of importance to quantum precision measurement during quantum information processing.

  16. The Probabilistic Efficiency Frontier: A Framework for Cost-Effectiveness Analysis in Germany Put into Practice for Hepatitis C Treatment Options.

    Science.gov (United States)

    Mühlbacher, Axel C; Sadler, Andrew

    2017-02-01

    The German Institute for Quality and Efficiency in Health Care (Institut für Qualität und Wirtschaftlichkeit im Gesundheitswesen) adapted the efficiency frontier (EF) approach to conform to statutory provisions on cost-effectiveness analysis of health technologies. EF serves as a framework for evaluating cost-effectiveness and indirectly for pricing and reimbursement decisions. To calculate an EF on the basis of single multidimensional benefit by taking patient preferences and uncertainty into account; to evaluate whether EF is useful to inform decision makers about cost-effectiveness of new therapies; and to find whether a treatment is efficient at given prices demonstrated through a case study on chronic hepatitis C. A single multidimensional benefit was calculated by linear additive aggregation of multiple patient-relevant end points. End points were identified and weighted by patients in a previous discrete-choice experiment (DCE). Aggregation of overall benefit was ascertained using preferences and clinical data. Monte-Carlo simulation was applied. Uncertainty was addressed by price acceptability curve (PAC) and net monetary benefit (NMB). The case study illustrates that progress in benefit and efficiency of hepatitis C virus treatments could be depicted very well with the EF. On the basis of cost, effect, and preference data, the latest generations of interferon-free treatments are shown to yield a positive NMB and be efficient at current prices. EF was implemented taking uncertainty into account. For the first time, a DCE was used with the EF. The study shows how DCEs in combination with EF, PAC, and NMB can contribute important information in the course of reimbursement and pricing decisions. Copyright © 2017 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

  17. [Cost effectiveness in treatment of acute myeloid leukemia].

    Science.gov (United States)

    Nordmann, P; Schaffner, A; Dazzi, H

    2000-12-23

    Although the rise in health costs is a widely debated issue, in Switzerland it was until recently taken for granted that patients are given the best available treatment regardless of cost. An example of a disease requiring costly treatment is acute myelogenous leukaemia (AML). To relate cost to benefit we calculated expenditure per life years gained. To assess costs we determined the real cost of treatment up to total remission, followed by consolidation or withdrawal of treatment or death. For survival time exceeding the 2-year observation period we used data from recent literature. The average cost of treatment ranges up to 107,592 Swiss francs (CHF). In 1997 we treated 23 leukaemia patients at Zurich University Hospital and gained a total of 210 life years. This represents an average cost of CHF 11,741 per life year gained. Chief cost items were therapy and personnel costs for nursing staff, followed by hotel business and personnel costs for doctors and diagnosis. Our results for AML treatment are far removed from the $61,500 ranging up to $166,000 discussed in the literature as the "critical" QALY (quality adjusted life years) value. This is the first time the actual costs of AML therapy have been shown for a Swiss cohort. Despite high initial treatment costs and success only in a limited number of patients, the expenditure per QALY is surprisingly low and shows clearly the effectiveness of apparently costly acute medicine.

  18. Approaches for Managing Uncertainty in Learning Management Systems

    OpenAIRE

    Radwan, Nouran M.; Senousy, M. Badr; Riad, Alaa El Din M.

    2016-01-01

    The notion of uncertainty in expert systems is dealing with vague data, incomplete information, and imprecise knowledge. Different uncertainty types which are imprecision, vagueness, ambiguity, and inconsistence need different handling models. Uncertain knowledge representation and analysis is an essential issue.

  19. Effectiveness and cost-effectiveness of computer and other electronic aids for smoking cessation: a systematic review and network meta-analysis.

    Science.gov (United States)

    Chen, Y-F; Madan, J; Welton, N; Yahaya, I; Aveyard, P; Bauld, L; Wang, D; Fry-Smith, A; Munafò, M R

    2012-01-01

    Smoking is harmful to health. On average, lifelong smokers lose 10 years of life, and about half of all lifelong smokers have their lives shortened by smoking. Stopping smoking reverses or prevents many of these harms. However, cessation services in the NHS achieve variable success rates with smokers who want to quit. Approaches to behaviour change can be supplemented with electronic aids, and this may significantly increase quit rates and prevent a proportion of cases that relapse. The primary research question we sought to answer was: What is the effectiveness and cost-effectiveness of internet, pc and other electronic aids to help people stop smoking? We addressed the following three questions: (1) What is the effectiveness of internet sites, computer programs, mobile telephone text messages and other electronic aids for smoking cessation and/or reducing relapse? (2) What is the cost-effectiveness of incorporating internet sites, computer programs, mobile telephone text messages and other electronic aids into current nhs smoking cessation programmes? and (3) What are the current gaps in research into the effectiveness of internet sites, computer programs, mobile telephone text messages and other electronic aids to help people stop smoking? For the effectiveness review, relevant primary studies were sought from The Cochrane Library [Cochrane Central Register of Controlled Trials (CENTRAL)] 2009, Issue 4, and MEDLINE (Ovid), EMBASE (Ovid), PsycINFO (Ovid), Health Management Information Consortium (HMIC) (Ovid) and Cumulative Index to Nursing and Allied Health Literature (CINAHL) (EBSCOhost) from 1980 to December 2009. In addition, NHS Economic Evaluation Database (NHS EED) and Database of Abstracts of Reviews of Effects (DARE) were searched for information on cost-effectiveness and modelling for the same period. Reference lists of included studies and of relevant systematic reviews were examined to identify further potentially relevant studies. Research registries

  20. Cost-effectiveness of EOB-MRI for Hepatocellular Carcinoma in Japan.

    Science.gov (United States)

    Nishie, Akihiro; Goshima, Satoshi; Haradome, Hiroki; Hatano, Etsuro; Imai, Yasuharu; Kudo, Masatoshi; Matsuda, Masanori; Motosugi, Utaroh; Saitoh, Satoshi; Yoshimitsu, Kengo; Crawford, Bruce; Kruger, Eliza; Ball, Graeme; Honda, Hiroshi

    2017-04-01

    The objective of the study was to evaluate the cost-effectiveness of gadoxetic acid-enhanced magnetic resonance imaging (EOB-MRI) in the diagnosis and treatment of hepatocellular carcinoma (HCC) in Japan compared with extracellular contrast media-enhanced MRI (ECCM-MRI) and contrast media-enhanced computed tomography (CE-CT) scanning. A 6-stage Markov model was developed to estimate lifetime direct costs and clinical outcomes associated with EOB-MRI. Diagnostic sensitivity and specificity, along with clinical data on HCC survival, recurrence, treatment patterns, costs, and health state utility values, were derived from predominantly Japanese publications. Parameters unavailable from publications were estimated in a Delphi panel of Japanese clinical experts who also confirmed the structure and overall approach of the model. Sensitivity analyses, including one-way, probabilistic, and scenario analyses, were conducted to account for uncertainty in the results. Over a lifetime horizon, EOB-MRI was associated with lower direct costs (¥2,174,869) and generated a greater number of quality-adjusted life years (QALYs) (9.502) than either ECCM-MRI (¥2,365,421, 9.303 QALYs) or CE-CT (¥2,482,608, 9.215 QALYs). EOB-MRI was superior to the other diagnostic strategies considered, and this finding was robust over sensitivity and scenario analyses. A majority of the direct costs associated with HCC in Japan were found to be costs of treatment. The model results revealed the superior cost-effectiveness of the EOB-MRI diagnostic strategy compared with ECCM-MRI and CE-CT. EOB-MRI could be the first-choice imaging modality for medical care of HCC among patients with hepatitis or liver cirrhosis in Japan. Widespread implementation of EOB-MRI could reduce health care expenditures, particularly downstream treatment costs, associated with HCC. Copyright © 2017 Elsevier HS Journals, Inc. All rights reserved.

  1. Cost-effectiveness of a national exercise referral programme for primary care patients in Wales: results of a randomised controlled trial

    Science.gov (United States)

    2013-01-01

    Background A recent HTA review concluded that there was a need for RCTs of exercise referral schemes (ERS) for people with a medical diagnosis who might benefit from exercise. Overall, there is still uncertainty as to the cost-effectiveness of ERS. Evaluation of public health interventions places challenges on conventional health economics approaches. This economic evaluation of a national public health intervention addresses this issue of where ERS may be most cost effective through subgroup analysis, particularly important at a time of financial constraint. Method This economic analysis included 798 individuals aged 16 and over (55% of the randomised controlled trial (RCT) sample) with coronary heart disease risk factors and/or mild to moderate anxiety, depression or stress. Individuals were referred by health professionals in a primary care setting to a 16 week national exercise referral scheme (NERS) delivered by qualified exercise professionals in local leisure centres in Wales, UK. Health-related quality of life, health care services use, costs per participant in NERS, and willingness to pay for NERS were measured at 6 and 12 months. Results The base case analysis assumed a participation cost of £385 per person per year, with a mean difference in QALYs between the two groups of 0.027. The incremental cost-effectiveness ratio was £12,111 per QALY gained. Probabilistic sensitivity analysis demonstrated an 89% probability of NERS being cost-effective at a payer threshold of £30,000 per QALY. When participant payments of £1 and £2 per session were considered, the cost per QALY fell from £12,111 (base case) to £10,926 and £9,741, respectively. Participants with a mental health risk factor alone or in combination with a risk of chronic heart disease generated a lower ICER (£10,276) compared to participants at risk of chronic heart disease only (£13,060). Conclusions Results of cost-effectiveness analyses suggest that NERS is cost saving in fully

  2. Multiple-pollutant cost-effectiveness of greenhouse gas mitigation measures in the UK agriculture

    International Nuclear Information System (INIS)

    Eory, Vera; Topp, Cairistiona F.E.; Moran, Dominic

    2013-01-01

    Highlights: ► Multiple-pollutant marginal abatement cost curves can inform integrated environmental policy. ► We incorporated the co-effects on NH 3 , NO 3 − , P and sediment, as monetary values, into the UK GHG MACC. ► Adding co-effects modifies the GHG MACC, though with little impact unless using high damage values. ► Further research is needed on the co-effects of GHG mitigation measures and on damage values. ► Analysis should focus on the co-effects of measures that are slightly above or below the threshold. -- Abstract: This paper develops multiple-pollutant marginal abatement cost curve analysis to identify an optimal set of greenhouse gas (GHG) mitigation measures considering the trade-offs and synergies with other environmental pollutants. The analysis is applied to UK agriculture, a sector expected to make a contribution to the national GHG mitigation effort. Previous analyses using marginal abatement cost curves (MACCs) have determined the sector's GHG abatement potential based on the cost-effectiveness of a variety of technically feasible mitigation measures. Most of these measures have external effects on other pollution loads arising from agricultural activities. Here the monetary values of four of the most important impacts to water and air (specifically ammonia, nitrate, phosphorous and sediment) are included in the cost-effectiveness analysis. The resulting multiple-pollutant marginal abatement cost curve (MP MACC) informs the design of sustainable climate change policies by showing how the MP MACC for the UK agriculture can differ from the GHG MACC. The analysis also highlights research gaps, and suggests a need to understand the wider environmental effects of GHG mitigation options and to reduce the uncertainty in pollutant damage cost estimates

  3. Procedural justice effects on self-esteem under certainty versus uncertainty emotions

    NARCIS (Netherlands)

    D. de Cremer (David); A. van Hiel (Alain)

    2008-01-01

    textabstractBuilding upon the idea that procedural justice effects are more pronounced when uncertainty is high, we proposed that recall of an uncertainty-eliciting emotion (fear) will render people more responsive to variations in procedural justice than will recall of a certainty-eliciting emotion

  4. Modeling for waste management associated with environmental-impact abatement under uncertainty.

    Science.gov (United States)

    Li, P; Li, Y P; Huang, G H; Zhang, J L

    2015-04-01

    Municipal solid waste (MSW) treatment can generate significant amounts of pollutants, and thus pose a risk on human health. Besides, in MSW management, various uncertainties exist in the related costs, impact factors, and objectives, which can affect the optimization processes and the decision schemes generated. In this study, a life cycle assessment-based interval-parameter programming (LCA-IPP) method is developed for MSW management associated with environmental-impact abatement under uncertainty. The LCA-IPP can effectively examine the environmental consequences based on a number of environmental impact categories (i.e., greenhouse gas equivalent, acid gas emissions, and respiratory inorganics), through analyzing each life cycle stage and/or major contributing process related to various MSW management activities. It can also tackle uncertainties existed in the related costs, impact factors, and objectives and expressed as interval numbers. Then, the LCA-IPP method is applied to MSW management for the City of Beijing, the capital of China, where energy consumptions and six environmental parameters [i.e., CO2, CO, CH4, NOX, SO2, inhalable particle (PM10)] are used as systematic tool to quantify environmental releases in entire life cycle stage of waste collection, transportation, treatment, and disposal of. Results associated with system cost, environmental impact, and the related policy implication are generated and analyzed. Results can help identify desired alternatives for managing MSW flows, which has advantages in providing compromised schemes under an integrated consideration of economic efficiency and environmental impact under uncertainty.

  5. Cost-effectiveness of human papillomavirus vaccination in low and middle income countries: a systematic review.

    Science.gov (United States)

    Fesenfeld, Michaela; Hutubessy, Raymond; Jit, Mark

    2013-08-20

    The World Health Organization recommends establishing that human papillomavirus vaccination is cost-effective before vaccine introduction. We searched Pubmed, Embase and the Cochrane Library to 1 April 2012 for economic evaluations of human papillomavirus vaccination in low and middle income countries. We found 25 articles, but almost all low income countries and many middle income countries lacked country-specific studies. Methods, assumptions and consequently results varied widely, even for studies conducted for the same country. Despite the heterogeneity, most studies conclude that vaccination is likely to be cost-effective and possibly even cost saving, particularly in settings without organized cervical screening programmes. However, study uncertainty could be reduced by clarity about vaccine prices and vaccine delivery costs. The review supports extending vaccination to low income settings where vaccine prices are competitive, donor funding is available, cervical cancer burden is high and screening options are limited. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Cost-effectiveness of different strategies for diagnosis of uncomplicated urinary tract infections in women presenting in primary care

    Science.gov (United States)

    Coupé, Veerle M. H.; Knottnerus, Bart J.; Geerlings, Suzanne E.; Moll van Charante, Eric P.; ter Riet, Gerben

    2017-01-01

    Background Uncomplicated Urinary Tract Infections (UTIs) are common in primary care resulting in substantial costs. Since antimicrobial resistance against antibiotics for UTIs is rising, accurate diagnosis is needed in settings with low rates of multidrug-resistant bacteria. Objective To compare the cost-effectiveness of different strategies to diagnose UTIs in women who contacted their general practitioner (GP) with painful and/or frequent micturition between 2006 and 2008 in and around Amsterdam, The Netherlands. Methods This is a model-based cost-effectiveness analysis using data from 196 women who underwent four tests: history, urine stick, sediment, dipslide, and the gold standard, a urine culture. Decision trees were constructed reflecting 15 diagnostic strategies comprising different parallel and sequential combinations of the four tests. Using the decision trees, for each strategy the costs and the proportion of women with a correct positive or negative diagnosis were estimated. Probabilistic sensitivity analysis was used to estimate uncertainty surrounding costs and effects. Uncertainty was presented using cost-effectiveness planes and acceptability curves. Results Most sequential testing strategies resulted in higher proportions of correctly classified women and lower costs than parallel testing strategies. For different willingness to pay thresholds, the most cost-effective strategies were: 1) performing a dipstick after a positive history for thresholds below €10 per additional correctly classified patient, 2) performing both a history and dipstick for thresholds between €10 and €17 per additional correctly classified patient, 3) performing a dipstick if history was negative, followed by a sediment if the dipstick was negative for thresholds between €17 and €118 per additional correctly classified patient, 4) performing a dipstick if history was negative, followed by a dipslide if the dipstick was negative for thresholds above €118 per

  7. Cost-effectiveness of different strategies for diagnosis of uncomplicated urinary tract infections in women presenting in primary care.

    Directory of Open Access Journals (Sweden)

    Judith E Bosmans

    Full Text Available Uncomplicated Urinary Tract Infections (UTIs are common in primary care resulting in substantial costs. Since antimicrobial resistance against antibiotics for UTIs is rising, accurate diagnosis is needed in settings with low rates of multidrug-resistant bacteria.To compare the cost-effectiveness of different strategies to diagnose UTIs in women who contacted their general practitioner (GP with painful and/or frequent micturition between 2006 and 2008 in and around Amsterdam, The Netherlands.This is a model-based cost-effectiveness analysis using data from 196 women who underwent four tests: history, urine stick, sediment, dipslide, and the gold standard, a urine culture. Decision trees were constructed reflecting 15 diagnostic strategies comprising different parallel and sequential combinations of the four tests. Using the decision trees, for each strategy the costs and the proportion of women with a correct positive or negative diagnosis were estimated. Probabilistic sensitivity analysis was used to estimate uncertainty surrounding costs and effects. Uncertainty was presented using cost-effectiveness planes and acceptability curves.Most sequential testing strategies resulted in higher proportions of correctly classified women and lower costs than parallel testing strategies. For different willingness to pay thresholds, the most cost-effective strategies were: 1 performing a dipstick after a positive history for thresholds below €10 per additional correctly classified patient, 2 performing both a history and dipstick for thresholds between €10 and €17 per additional correctly classified patient, 3 performing a dipstick if history was negative, followed by a sediment if the dipstick was negative for thresholds between €17 and €118 per additional correctly classified patient, 4 performing a dipstick if history was negative, followed by a dipslide if the dipstick was negative for thresholds above €118 per additional correctly classified

  8. Cost-effectiveness of different strategies for diagnosis of uncomplicated urinary tract infections in women presenting in primary care.

    Science.gov (United States)

    Bosmans, Judith E; Coupé, Veerle M H; Knottnerus, Bart J; Geerlings, Suzanne E; Moll van Charante, Eric P; Ter Riet, Gerben

    2017-01-01

    Uncomplicated Urinary Tract Infections (UTIs) are common in primary care resulting in substantial costs. Since antimicrobial resistance against antibiotics for UTIs is rising, accurate diagnosis is needed in settings with low rates of multidrug-resistant bacteria. To compare the cost-effectiveness of different strategies to diagnose UTIs in women who contacted their general practitioner (GP) with painful and/or frequent micturition between 2006 and 2008 in and around Amsterdam, The Netherlands. This is a model-based cost-effectiveness analysis using data from 196 women who underwent four tests: history, urine stick, sediment, dipslide, and the gold standard, a urine culture. Decision trees were constructed reflecting 15 diagnostic strategies comprising different parallel and sequential combinations of the four tests. Using the decision trees, for each strategy the costs and the proportion of women with a correct positive or negative diagnosis were estimated. Probabilistic sensitivity analysis was used to estimate uncertainty surrounding costs and effects. Uncertainty was presented using cost-effectiveness planes and acceptability curves. Most sequential testing strategies resulted in higher proportions of correctly classified women and lower costs than parallel testing strategies. For different willingness to pay thresholds, the most cost-effective strategies were: 1) performing a dipstick after a positive history for thresholds below €10 per additional correctly classified patient, 2) performing both a history and dipstick for thresholds between €10 and €17 per additional correctly classified patient, 3) performing a dipstick if history was negative, followed by a sediment if the dipstick was negative for thresholds between €17 and €118 per additional correctly classified patient, 4) performing a dipstick if history was negative, followed by a dipslide if the dipstick was negative for thresholds above €118 per additional correctly classified patient

  9. Cost-effectiveness analysis and mortality impact estimation of scaling-up pregnancy test kits in Madagascar, Ethiopia and Malawi.

    Science.gov (United States)

    Kolesar, Robert J; Audibert, Martine; Comfort, Alison B

    2017-07-01

    Cost-effective, innovative approaches are needed to accelerate progress towards ending preventable infant, child and maternal mortality. To inform policy decisions, we conducted a cost-effectiveness analysis of adding urine pregnancy test kits to the maternal and reproductive services package offered at the community level in Madagascar, Ethiopia and Malawi. We used a decision tree model to compare the intervention with the status quo for each country. We also completed single factor sensitivity analyses and Monte Carlo simulations with 10 000 iterations to generate the probability distribution of the estimates and uncertainty limits. Among a hypothetical cohort of 100 000 women of reproductive age, we estimate that over a 1-year period, the intervention would save 26, 35 and 48 lives in Madagascar, Ethiopia, and Malawi, respectively. The Incremental Cost Effectiveness Ratio (ICER) for the cost per life saved varies by country: $2311 [95% Uncertainty Interval (UI): $1699; $3454] in Madagascar; $2969 [UI: $2260; $5041] in Ethiopia and $1228 [UI: $918; $1777] in Malawi. This equates to an average cost per Disability Adjusted Life Year (DALY) averted of $36.28, $47.95 and $21.92, respectively. Based on WHO criteria and a comparison with other maternal, newborn, and child health interventions, we conclude that the addition of urine pregnancy tests to an existing community health worker maternal and reproductive services package is highly cost-effective in all three countries. To optimize uptake of family planning and antenatal care services and, in turn, accelerate the reduction of mortality and DALYs, decision makers and program planners should consider adding urine pregnancy tests to the community-level package of services. © The Author 2017. Published by Oxford University Press in association with The London School of Hygiene and Tropical Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  10. Studying the effect of clinical uncertainty on physicians' decision-making using ILIAD.

    Science.gov (United States)

    Anderson, J D; Jay, S J; Weng, H C; Anderson, M M

    1995-01-01

    The influence of uncertainty on physicians' practice behavior is not well understood. In this research, ILIAD, a diagnostic expert system, has been used to study physicians' responses to uncertainty and how their responses affected clinical performance. The simulation mode of ILIAD was used to standardize the presentation and scoring of two cases to 46 residents in emergency medicine, internal medicine, family practice and transitional medicine at Methodist Hospital of Indiana. A questionnaire was used to collect additional data on how physicians respond to clinical uncertainty. A structural equation model was developed, estimated, and tested. The results indicate that stress that physicians experience in dealing with clinical uncertainty has a negative effect on their clinical performance. Moreover, the way that physicians respond to uncertainty has positive and negative effects on their performance. Open discussions with patients about clinical decisions and the use of practice guidelines improves performance. However, when the physician's clinical decisions are influenced by patient demands or their peers, their performance scores decline.

  11. Particle Dark Matter constraints: the effect of Galactic uncertainties

    Energy Technology Data Exchange (ETDEWEB)

    Benito, Maria; Bernal, Nicolás; Iocco, Fabio [ICTP South American Institute for Fundamental Research Instituto de Física Teórica - Universidade Estadual Paulista (UNESP) Rua Dr. Bento Teobaldo Ferraz 271, 01140-070 São Paulo, SP Brazil (Brazil); Bozorgnia, Nassim; Calore, Francesca, E-mail: mariabenitocst@gmail.com, E-mail: nicolas.bernal@uan.edu.co, E-mail: n.bozorgnia@uva.nl, E-mail: calore@lapth.cnrs.fr, E-mail: fabio.iocco.astro@gmail.com [GRAPPA Institute, Institute for Theoretical Physics Amsterdam and Delta Institute for Theoretical Physics, University of Amsterdam, Science Park 904, 1098 XH Amsterdam (Netherlands)

    2017-02-01

    Collider, space, and Earth based experiments are now able to probe several extensions of the Standard Model of particle physics which provide viable dark matter candidates. Direct and indirect dark matter searches rely on inputs of astrophysical nature, such as the local dark matter density or the shape of the dark matter density profile in the target in object. The determination of these quantities is highly affected by astrophysical uncertainties. The latter, especially those for our own Galaxy, are ill-known, and often not fully accounted for when analyzing the phenomenology of particle physics models. In this paper we present a systematic, quantitative estimate of how astrophysical uncertainties on Galactic quantities (such as the local galactocentric distance, circular velocity, or the morphology of the stellar disk and bulge) propagate to the determination of the phenomenology of particle physics models, thus eventually affecting the determination of new physics parameters. We present results in the context of two specific extensions of the Standard Model (the Singlet Scalar and the Inert Doublet) that we adopt as case studies for their simplicity in illustrating the magnitude and impact of such uncertainties on the parameter space of the particle physics model itself. Our findings point toward very relevant effects of current Galactic uncertainties on the determination of particle physics parameters, and urge a systematic estimate of such uncertainties in more complex scenarios, in order to achieve constraints on the determination of new physics that realistically include all known uncertainties.

  12. The Impact of Debt Limitations and Referenda Requirements on the Cost of School District Bond Issues

    Science.gov (United States)

    Harris, Mary H.; Munley, Vincent G.

    2011-01-01

    One distinction between the markets for corporate and municipal bonds involves institutional constraints that apply to some municipal bond issues. This research focuses on how public finance institutions, in particular explicit debt limits and referenda requirements, affect the borrowing cost of individual school district bond issues. The…

  13. Creation of a long-term data record of total O3 - issues and challenges in prescribing the uncertainties

    Science.gov (United States)

    Haffner, D. P.; Bhartia, P. K.; Li, J. Y.

    2012-12-01

    With the launch of the BUV instrument on NASA's Nimbus-4 satellite in April 1970, ozone became one of the first atmospheric variables to be measured from space with high accuracy. By 1980, the quality of total column ozone measured from the TOMS instrument on the Nimbus-7 satellite had improved to the point that it started to be used to identify poorly calibrated instruments in the venerable Dobson ground-based network. Now we have a total ozone record spanning 42 years created by more than a dozen instruments. We will discuss the issues and challenges that we have faced in creating a consistent long-term record and in providing uncertainty estimates. This work is not yet finished. We are currently developing a new algorithm (Version 9) that will be used to reprocess the entire record. The main motivation for developing this algorithm is not so much to improve the quality of the data, which is quite high already, but to provide better estimates of uncertainties when errors are spatially and temporally correlated, and to develop better techniques to catch "Black Swan" events (BSE). These are events that occur infrequently but cause errors larger than expected by Gaussian probability distribution. For example, the eruption of El Chichón revealed that our ozone algorithm had unexpected sensitivity to volcanic SO2, and evidence of the ozone hole was initially interpreted as a problem with the TOMS instrument. We also provide mathematical operators that can be applied by sophisticated users to compute their own uncertainties for their particular applications. This is necessary because uncertainties change in complex ways when the data are smoothed or averaged. The modern data archival system should be designed to accommodate such operators and provide software for using them.

  14. Neural-Network-Based Robust Optimal Tracking Control for MIMO Discrete-Time Systems With Unknown Uncertainty Using Adaptive Critic Design.

    Science.gov (United States)

    Liu, Lei; Wang, Zhanshan; Zhang, Huaguang

    2018-04-01

    This paper is concerned with the robust optimal tracking control strategy for a class of nonlinear multi-input multi-output discrete-time systems with unknown uncertainty via adaptive critic design (ACD) scheme. The main purpose is to establish an adaptive actor-critic control method, so that the cost function in the procedure of dealing with uncertainty is minimum and the closed-loop system is stable. Based on the neural network approximator, an action network is applied to generate the optimal control signal and a critic network is used to approximate the cost function, respectively. In contrast to the previous methods, the main features of this paper are: 1) the ACD scheme is integrated into the controllers to cope with the uncertainty and 2) a novel cost function, which is not in quadric form, is proposed so that the total cost in the design procedure is reduced. It is proved that the optimal control signals and the tracking errors are uniformly ultimately bounded even when the uncertainty exists. Finally, a numerical simulation is developed to show the effectiveness of the present approach.

  15. Report of a CSNI workshop on uncertainty analysis methods. Volume 1 + 2

    International Nuclear Information System (INIS)

    Wickett, A.J.; Yadigaroglu, G.

    1994-08-01

    The OECD NEA CSNI Principal Working Group 2 (PWG2) Task Group on Thermal Hydraulic System Behaviour (TGTHSB) has, in recent years, received presentations of a variety of different methods to analyze the uncertainty in the calculations of advanced unbiased (best estimate) codes. Proposals were also made for an International Standard Problem (ISP) to compare the uncertainty analysis methods. The objectives for the Workshop were to discuss and fully understand the principles of uncertainty analysis relevant to LOCA modelling and like problems, to examine the underlying issues from first principles, in preference to comparing and contrasting the currently proposed methods, to reach consensus on the issues identified as far as possible while not avoiding the controversial aspects, to identify as clearly as possible unreconciled differences, and to issue a Status Report. Eight uncertainty analysis methods were presented. A structured discussion of various aspects of uncertainty analysis followed - the need for uncertainty analysis, identification and ranking of uncertainties, characterisation, quantification and combination of uncertainties and applications, resources and future developments. As a result, the objectives set out above were, to a very large extent, achieved. Plans for the ISP were also discussed. Volume 1 contains a record of the discussions on uncertainty methods. Volume 2 is a compilation of descriptions of the eight uncertainty analysis methods presented at the workshop

  16. Comparison between different uncertainty propagation methods in multivariate analysis: An application in the bivariate case

    International Nuclear Information System (INIS)

    Mullor, R.; Sanchez, A.; Martorell, S.; Martinez-Alzamora, N.

    2011-01-01

    Safety related systems performance optimization is classically based on quantifying the effects that testing and maintenance activities have on reliability and cost (R+C). However, R+C quantification is often incomplete in the sense that important uncertainties may not be considered. An important number of studies have been published in the last decade in the field of R+C based optimization considering uncertainties. They have demonstrated that inclusion of uncertainties in the optimization brings the decision maker insights concerning how uncertain the R+C results are and how this uncertainty does matter as it can result in differences in the outcome of the decision making process. Several methods of uncertainty propagation based on the theory of tolerance regions have been proposed in the literature depending on the particular characteristics of the variables in the output and their relations. In this context, the objective of this paper focuses on the application of non-parametric and parametric methods to analyze uncertainty propagation, which will be implemented on a multi-objective optimization problem where reliability and cost act as decision criteria and maintenance intervals act as decision variables. Finally, a comparison of results of these applications and the conclusions obtained are presented.

  17. Comparison between different uncertainty propagation methods in multivariate analysis: An application in the bivariate case

    Energy Technology Data Exchange (ETDEWEB)

    Mullor, R. [Dpto. Estadistica e Investigacion Operativa, Universidad Alicante (Spain); Sanchez, A., E-mail: aisanche@eio.upv.e [Dpto. Estadistica e Investigacion Operativa Aplicadas y Calidad, Universidad Politecnica Valencia, Camino de Vera s/n 46022 (Spain); Martorell, S. [Dpto. Ingenieria Quimica y Nuclear, Universidad Politecnica Valencia (Spain); Martinez-Alzamora, N. [Dpto. Estadistica e Investigacion Operativa Aplicadas y Calidad, Universidad Politecnica Valencia, Camino de Vera s/n 46022 (Spain)

    2011-06-15

    Safety related systems performance optimization is classically based on quantifying the effects that testing and maintenance activities have on reliability and cost (R+C). However, R+C quantification is often incomplete in the sense that important uncertainties may not be considered. An important number of studies have been published in the last decade in the field of R+C based optimization considering uncertainties. They have demonstrated that inclusion of uncertainties in the optimization brings the decision maker insights concerning how uncertain the R+C results are and how this uncertainty does matter as it can result in differences in the outcome of the decision making process. Several methods of uncertainty propagation based on the theory of tolerance regions have been proposed in the literature depending on the particular characteristics of the variables in the output and their relations. In this context, the objective of this paper focuses on the application of non-parametric and parametric methods to analyze uncertainty propagation, which will be implemented on a multi-objective optimization problem where reliability and cost act as decision criteria and maintenance intervals act as decision variables. Finally, a comparison of results of these applications and the conclusions obtained are presented.

  18. The valuation of external costs: An overview of issues and state actions

    International Nuclear Information System (INIS)

    Caverhill, E.J.

    1992-01-01

    The valuation of externalities helps determine the cost effectiveness of environmentally superior resources that would not be cost effective on a direct cost comparison to utility avoided costs. Explicitly monetizing externalities appears to be the best way to meet the criteria of consistency across resource options and pollutants and allowing selection of societally least-cost resources among a variety of resource types. Environmental costs should be defined so as not to exclude any potential external effects, including all environmental, social, and economic effects. For practical purposes, the definition could probably include only environmental externalities without materially affecting resource decisions in the foreseeable future for most North American utilities. More specifically, a comprehensive list of external costs should at least include emissions of pollutants such as SO 2 , CO, NO x , volatile organics, and greenhouse gases; thermal effluents; solid wastes; risk of catastrophic accidents; and for hydro projects, destruction of habitat and recreational areas, and mercury accumulation in reservoirs. Environmental effects should then be counted and valued, most commonly by damage costing or regulatory cost of control. Some utilities and other parties have proposed a market-based approach to valuing externalities, determining the marginal cost of controlling emissions by the market price of emissions allowances. Quantification of environmental costs, ensuring consistency among externality sources, and estimation of avoided externality costs are also discussed. Examples are presented of externality values selected in a number of areas of the USA. 11 refs., 5 figs

  19. A lesson in business: cost-effectiveness analysis of a novel financial incentive intervention for increasing physical activity in the workplace.

    Science.gov (United States)

    Dallat, Mary Anne T; Hunter, Ruth F; Tully, Mark A; Cairns, Karen J; Kee, Frank

    2013-10-10

    Recently both the UK and US governments have advocated the use of financial incentives to encourage healthier lifestyle choices but evidence for the cost-effectiveness of such interventions is lacking. Our aim was to perform a cost-effectiveness analysis (CEA) of a quasi-experimental trial, exploring the use of financial incentives to increase employee physical activity levels, from a healthcare and employer's perspective. Employees used a 'loyalty card' to objectively monitor their physical activity at work over 12 weeks. The Incentive Group (n=199) collected points and received rewards for minutes of physical activity completed. The No Incentive Group (n=207) self-monitored their physical activity only. Quality of life (QOL) and absenteeism were assessed at baseline and 6 months follow-up. QOL scores were also converted into productivity estimates using a validated algorithm. The additional costs of the Incentive Group were divided by the additional quality adjusted life years (QALYs) or productivity gained to calculate incremental cost effectiveness ratios (ICERs). Cost-effectiveness acceptability curves (CEACs) and population expected value of perfect information (EVPI) was used to characterize and value the uncertainty in our estimates. The Incentive Group performed more physical activity over 12 weeks and by 6 months had achieved greater gains in QOL and productivity, although these mean differences were not statistically significant. The ICERs were £2,900/QALY and £2,700 per percentage increase in overall employee productivity. Whilst the confidence intervals surrounding these ICERs were wide, CEACs showed a high chance of the intervention being cost-effective at low willingness-to-pay (WTP) thresholds. The Physical Activity Loyalty card (PAL) scheme is potentially cost-effective from both a healthcare and employer's perspective but further research is warranted to reduce uncertainty in our results. It is based on a sustainable "business model" which

  20. Improving cost-effectiveness and mitigating risks of renewable energy requirements

    Science.gov (United States)

    Griffin, James P.

    Policy makers at the federal and state levels of government are debating actions to reduce U.S. greenhouse gas emissions and dependence on oil as an energy source. Several concerns drive this debate: sharp rises in energy prices, increasing unease about the risks of climate change, energy security, and interest in expanding the domestic renewable energy industry. Renewable energy requirements are frequently proposed to address these concerns, and are currently in place, in various forms, at the federal and state levels of government. These policies specify that a certain portion of the energy supply come from renewable energy sources. This dissertation focuses on a specific proposal, known as 25 X 25, which requires 25% of electricity and motor vehicle transportation fuels supplied to U.S. consumers to come from renewable energy sources, such as wind power and ethanol, by 2025. This dissertation builds on prior energy policy analysis, and more specifically analyses of renewable energy requirements, by assessing the social welfare implications of a 25 x 25 policy and applying new methods of uncertainty analysis to multiple policy options decision makers can use to implement the policy. These methods identify policy options that can improve the cost-effectiveness and reduce the risks of renewable energy requirements. While the dissertation focuses on a specific policy, the research methods and findings are applicable to other renewable energy requirement policies. In the dissertation, I analyze six strategies for implementing a 25 x 25 policy across several hundred scenarios that represent plausible futures for uncertainties in energy markets, such as renewable energy costs, energy demand, and fossil fuel prices. The strategies vary in the availability of resources that qualify towards the policy requirement and the use of a "safety valve" that allows refiners and utilities to pay a constant fee after renewable energy costs reach a predetermined threshold. I test

  1. Cost-effectiveness analysis of endoscopic tympanoplasty versus microscopic tympanoplasty for chronic otitis media in Taiwan.

    Science.gov (United States)

    Tseng, Chih-Chieh; Lai, Ming-Tang; Wu, Chia-Che; Yuan, Sheng-Po; Ding, Yi-Fang

    2018-03-01

    Health care systems and physicians need to conform to budgets and streamline resources to provide cost-effective quality care. Although endoscopic tympanoplasty (ET) has been performed for decades, no studies on the cost-effectiveness of ET and microscopic tympanoplasty (MT) for treating chronic otitis media have been published. The present study aimed to compare the cost-effectiveness of ET and MT for treating chronic otitis media. This study was performed using a Cohort-style Markov decision-tree economic model with a 30-year time horizon. The economic perspective was that of a third-party payer (Taiwan National Health Insurance System). Two treatment strategies were compared, namely ET and MT. The primary outcome was the incremental cost per quality-adjusted life year (QALY). Probabilities were obtained from meta-analyses. Costs were obtained from the published literature and Taiwan National Health Insurance System database. Multiple sensitivity analyses were performed to account for data uncertainty. The reference case revealed that the total cost of ET was $NT 20,901 for 17.08 QALY per patient. By contrast, the total cost of MT was $NT 21,171 for 17.15 QALY per patient. The incremental cost effectiveness ratio for ET versus that of MT was $NT 3703 per QALY. The cost-effectiveness acceptability curve indicated that ET was comparable to MT at a willingness-to-pay threshold of larger than $NT 35,000 per QALY. This cost-effectiveness analysis indicates that ET is comparable to MT for treating chronic otitis media in Taiwan. This result provides the latest information for physicians, the government, and third-party payers to select proper clinical practice. Copyright © 2017. Published by Elsevier Taiwan LLC.

  2. Uncertainty and sensitivity analysis of chronic exposure results with the MACCS reactor accident consequence model

    International Nuclear Information System (INIS)

    Helton, J.C; Johnson, J.D; Rollstin, J.A; Shiver, A.W; Sprung, J.L

    1995-01-01

    Uncertainty and sensitivity analysis techniques based on Latin hypercube sampling, partial correlation analysis and stepwise regression analysis are used in an investigation with the MACCS model of the chronic exposure pathways associated with a severe accident at a nuclear power station. The primary purpose of this study is to provide guidance on the variables to be considered in future review work to reduce the uncertainty in the important variables used in the calculation of reactor accident consequences. The effects of 75 imprecisely known input variables on the following reactor accident consequences are studied: crop growing-season dose, crop long-term dose, water ingestion dose, milk growing-season dose, long-term groundshine dose, long-term inhalation dose, total food pathways dose, total ingestion pathways dose, total long-term pathways dose, total latent cancer fatalities, area-dependent cost, crop disposal cost, milk disposal cost, population-dependent cost, total economic cost, condemnation area, condemnation population, crop disposal area and milk disposal area. When the predicted variables are considered collectively, the following input variables were found to be the dominant contributors to uncertainty: dry deposition velocity, transfer of cesium from animal feed to milk, transfer of cesium from animal feed to meet, ground concentration of Cs-134 at which the disposal of milk products will be initiated, transfer of Sr-90 from soil to legumes, maximum allowable ground concentration of Sr-90 for production of crops, fraction of cesium entering surface water that is consumed in drinking water, groundshine shielding factor, scale factor defining resuspension, dose reduction associated with decontamination, and ground concentration of I-131 at which disposal of crops will be initiated due to accidents that occur during the growing season. Reducing the uncertainty in the preceding variables was found to substantially reduce the uncertainty in the

  3. GIS to support cost-effective decisions on renewable sources applications for low temperature geothermal energy

    CERN Document Server

    Gemelli, Alberto; Diamantini, Claudia; Longhi, Sauro

    2013-01-01

    Through the results of a developed case study of information system for low temperature geothermal energy, GIS to Support Cost-effective Decisions on Renewable Sources addresses the issue of the use of Geographic Information Systems (GIS) in evaluating cost-effectiveness of renewable resource exploitation regional scale. Focusing on the design of a Decision Support System, a process is presented aimed to transform geographic data into knowledge useful for analysis and decision-making on the economic exploitation of geothermal energy. This detailed description includes a literature review and technical issues related to data collection, data mining, decision analysis for the informative system developed for the case study. A multi-disciplinary approach to GIS design is presented which is also an innovative example of fusion of georeferenced data acquired from multiple sources including remote sensing, networks of sensors and socio-economic censuses. GIS to Support Cost-effective Decisions on Renewable Sources ...

  4. Evaluating a multispecies adaptive management framework: Must uncertainty impede effective decision-making?

    Science.gov (United States)

    Smith, David R.; McGowan, Conor P.; Daily, Jonathan P.; Nichols, James D.; Sweka, John A.; Lyons, James E.

    2013-01-01

    Application of adaptive management to complex natural resource systems requires careful evaluation to ensure that the process leads to improved decision-making. As part of that evaluation, adaptive policies can be compared with alternative nonadaptive management scenarios. Also, the value of reducing structural (ecological) uncertainty to achieving management objectives can be quantified.A multispecies adaptive management framework was recently adopted by the Atlantic States Marine Fisheries Commission for sustainable harvest of Delaware Bay horseshoe crabs Limulus polyphemus, while maintaining adequate stopover habitat for migrating red knots Calidris canutus rufa, the focal shorebird species. The predictive model set encompassed the structural uncertainty in the relationships between horseshoe crab spawning, red knot weight gain and red knot vital rates. Stochastic dynamic programming was used to generate a state-dependent strategy for harvest decisions given that uncertainty. In this paper, we employed a management strategy evaluation approach to evaluate the performance of this adaptive management framework. Active adaptive management was used by including model weights as state variables in the optimization and reducing structural uncertainty by model weight updating.We found that the value of information for reducing structural uncertainty is expected to be low, because the uncertainty does not appear to impede effective management. Harvest policy responded to abundance levels of both species regardless of uncertainty in the specific relationship that generated those abundances. Thus, the expected horseshoe crab harvest and red knot abundance were similar when the population generating model was uncertain or known, and harvest policy was robust to structural uncertainty as specified.Synthesis and applications. The combination of management strategy evaluation with state-dependent strategies from stochastic dynamic programming was an informative approach to

  5. Counting the cost: estimating the economic benefit of pedophile treatment programs.

    Science.gov (United States)

    Shanahan, M; Donato, R

    2001-04-01

    The principal objective of this paper is to identify the economic costs and benefits of pedophile treatment programs incorporating both the tangible and intangible cost of sexual abuse to victims. Cost estimates of cognitive behavioral therapy programs in Australian prisons are compared against the tangible and intangible costs to victims of being sexually abused. Estimates are prepared that take into account a number of problematic issues. These include the range of possible recidivism rates for treatment programs; the uncertainty surrounding the number of child sexual molestation offences committed by recidivists; and the methodological problems associated with estimating the intangible costs of sexual abuse on victims. Despite the variation in parameter estimates that impact on the cost-benefit analysis of pedophile treatment programs, it is found that potential range of economic costs from child sexual abuse are substantial and the economic benefits to be derived from appropriate and effective treatment programs are high. Based on a reasonable set of parameter estimates, in-prison, cognitive therapy treatment programs for pedophiles are likely to be of net benefit to society. Despite this, a critical area of future research must include further methodological developments in estimating the quantitative impact of child sexual abuse in the community.

  6. Electricity supply industry modelling for multiple objectives under demand growth uncertainty

    International Nuclear Information System (INIS)

    Heinrich, G.; Basson, L.; Howells, M.; Petrie, J.

    2007-01-01

    Appropriate energy-environment-economic (E3) modelling provides key information for policy makers in the electricity supply industry (ESI) faced with navigating a sustainable development path. Key challenges include engaging with stakeholder values and preferences, and exploring trade-offs between competing objectives in the face of underlying uncertainty. As a case study we represent the South African ESI using a partial equilibrium E3 modelling approach, and extend the approach to include multiple objectives under selected future uncertainties. This extension is achieved by assigning cost penalties to non-cost attributes to force the model's least-cost objective function to better satisfy non-cost criteria. This paper incorporates aspects of flexibility to demand growth uncertainty into each future expansion alternative by introducing stochastic programming with recourse into the model. Technology lead times are taken into account by the inclusion of a decision node along the time horizon where aspects of real options theory are considered within the planning process. Hedging in the recourse programming is automatically translated from being purely financial, to include the other attributes that the cost penalties represent. From a retrospective analysis of the cost penalties, the correct market signals, can be derived to meet policy goal, with due regard to demand uncertainty. (author)

  7. Icarus's discovery: Acting on global climate change in the face of uncertainty

    International Nuclear Information System (INIS)

    Brooks, D.G.; Maracas, K.B.; Hayslip, R.M.

    1994-01-01

    The mythological character Icarus had the misfortune of learning the consequences of his decision to fly too near the sun at the same time he employed his decision. Although Daedalus tried to reduce the uncertainties of his son's decision by warning Icarus of the possible outcome, Icarus had no empirical knowledge of what would actually happen until his waxen wings melted and he fell to the sea. Like Icarus, man has no empirical knowledge or conclusive evidence today of the possible effects of global climate change. And though the consequences of policy decisions toward global climate change may not be as catastrophic as falling into the sea, the social and economic impacts of those decisions will be substantial. There are broad uncertainties related to the scientific and ecological aspects of global climate change. But clearly the ''politics'' of global climate change issues are moving at a faster rate than the science. There is a public outcry for action now, in the face of uncertainty. This paper profiles a case study of a southwestern utility's use of multi-attribute preference theory to reduce uncertainties and analyze its options for addressing global climate change issues

  8. Costs and Cost-Effectiveness of Plasmodium vivax Control.

    Science.gov (United States)

    White, Michael T; Yeung, Shunmay; Patouillard, Edith; Cibulskis, Richard

    2016-12-28

    The continued success of efforts to reduce the global malaria burden will require sustained funding for interventions specifically targeting Plasmodium vivax The optimal use of limited financial resources necessitates cost and cost-effectiveness analyses of strategies for diagnosing and treating P. vivax and vector control tools. Herein, we review the existing published evidence on the costs and cost-effectiveness of interventions for controlling P. vivax, identifying nine studies focused on diagnosis and treatment and seven studies focused on vector control. Although many of the results from the much more extensive P. falciparum literature can be applied to P. vivax, it is not always possible to extrapolate results from P. falciparum-specific cost-effectiveness analyses. Notably, there is a need for additional studies to evaluate the potential cost-effectiveness of radical cure with primaquine for the prevention of P. vivax relapses with glucose-6-phosphate dehydrogenase testing. © The American Society of Tropical Medicine and Hygiene.

  9. Real Options Effect of Uncertainty and Labor Demand Shocks on the Housing Market

    OpenAIRE

    Lee, Gabriel; Nguyen Thanh, Binh; Strobel, Johannes

    2016-01-01

    This paper shows that uncertainty affects the housing market in two significant ways. First, uncertainty shocks adversely affect housing prices but not the quantities that are traded. Controlling for a broad set of variables in fixed-effects regressions, we find that uncertainty shocks reduce housing prices and median sales prices in the amount of 1.4% and 1.8%, respectively, but the effect is not statistically significant for the percentage changes of all homes sold. Second, when...

  10. Regulatory uncertainty and the associated business risk for emerging technologies

    International Nuclear Information System (INIS)

    Hoerr, Robert A.

    2011-01-01

    An oversight system specifically concerned with nanomaterials should be flexible enough to take into account the unique aspects of individual novel materials and the settings in which they might be used, while recognizing that heretofore unrecognized safety issues may require future modifications. This article considers a question not explicitly considered by the project team: what is the risk that uncertainty over how regulatory oversight will be applied to nanomaterials will delay or block the development of this emerging technology, thereby depriving human health of potential and substantial benefits? An ambiguous regulatory environment could delay the availability of valuable new technology and therapeutics for human health by reducing access to investment capital. Venture capitalists list regulatory uncertainty as a major reason not to invest at all in certain areas. Uncertainty is far more difficult to evaluate than risk, which lends itself to quantitative models and can be factored into projections of return on possible investments. Loss of time has a large impact on investment return. An examination of regulatory case histories suggests that an increase in regulatory resting requirement, where the path is well-defined, is far less costly than a delay of a year or more in achieving product approval and market launch.

  11. Regulatory uncertainty and the associated business risk for emerging technologies

    Science.gov (United States)

    Hoerr, Robert A.

    2011-04-01

    An oversight system specifically concerned with nanomaterials should be flexible enough to take into account the unique aspects of individual novel materials and the settings in which they might be used, while recognizing that heretofore unrecognized safety issues may require future modifications. This article considers a question not explicitly considered by the project team: what is the risk that uncertainty over how regulatory oversight will be applied to nanomaterials will delay or block the development of this emerging technology, thereby depriving human health of potential and substantial benefits? An ambiguous regulatory environment could delay the availability of valuable new technology and therapeutics for human health by reducing access to investment capital. Venture capitalists list regulatory uncertainty as a major reason not to invest at all in certain areas. Uncertainty is far more difficult to evaluate than risk, which lends itself to quantitative models and can be factored into projections of return on possible investments. Loss of time has a large impact on investment return. An examination of regulatory case histories suggests that an increase in regulatory resting requirement, where the path is well-defined, is far less costly than a delay of a year or more in achieving product approval and market launch.

  12. Information theoretic quantification of diagnostic uncertainty.

    Science.gov (United States)

    Westover, M Brandon; Eiseman, Nathaniel A; Cash, Sydney S; Bianchi, Matt T

    2012-01-01

    Diagnostic test interpretation remains a challenge in clinical practice. Most physicians receive training in the use of Bayes' rule, which specifies how the sensitivity and specificity of a test for a given disease combine with the pre-test probability to quantify the change in disease probability incurred by a new test result. However, multiple studies demonstrate physicians' deficiencies in probabilistic reasoning, especially with unexpected test results. Information theory, a branch of probability theory dealing explicitly with the quantification of uncertainty, has been proposed as an alternative framework for diagnostic test interpretation, but is even less familiar to physicians. We have previously addressed one key challenge in the practical application of Bayes theorem: the handling of uncertainty in the critical first step of estimating the pre-test probability of disease. This essay aims to present the essential concepts of information theory to physicians in an accessible manner, and to extend previous work regarding uncertainty in pre-test probability estimation by placing this type of uncertainty within a principled information theoretic framework. We address several obstacles hindering physicians' application of information theoretic concepts to diagnostic test interpretation. These include issues of terminology (mathematical meanings of certain information theoretic terms differ from clinical or common parlance) as well as the underlying mathematical assumptions. Finally, we illustrate how, in information theoretic terms, one can understand the effect on diagnostic uncertainty of considering ranges instead of simple point estimates of pre-test probability.

  13. Urban drainage models simplifying uncertainty analysis for practitioners

    DEFF Research Database (Denmark)

    Vezzaro, Luca; Mikkelsen, Peter Steen; Deletic, Ana

    2013-01-01

    in each measured/observed datapoint; an issue that is commonly overlooked in the uncertainty analysis of urban drainage models. This comparison allows the user to intuitively estimate the optimum number of simulations required to conduct uncertainty analyses. The output of the method includes parameter......There is increasing awareness about uncertainties in the modelling of urban drainage systems and, as such, many new methods for uncertainty analyses have been developed. Despite this, all available methods have limitations which restrict their widespread application among practitioners. Here...

  14. Cost-effectiveness of point-of-care C-reactive protein testing to inform antibiotic prescribing decisions

    Science.gov (United States)

    Oppong, Raymond; Jit, Mark; Smith, Richard D; Butler, Christopher C; Melbye, Hasse; Mölstad, Sigvard; Coast, Joanna

    2013-01-01

    Background Point-of-care C-reactive protein (POCCRP) is a biomarker of inflammation that offers clinicians a rapid POC test to guide antibiotic prescribing decisions for acute cough and lower respiratory tract infections (LRTI). However, evidence that POCCRP is cost-effective is limited, particularly outside experimental settings. Aim To assess the cost-effectiveness of POCCRP as a diagnostic tool for acute cough and LRTI from the perspective of the health service. Design and setting Observational study of the presentation, management, and outcomes of patients with acute cough and LRTI in primary care settings in Norway and Sweden. Method Using hierarchical regression, data were analysed in terms of the effect on antibiotic use, cost, and patient outcomes (symptom severity after 7 and 14 days, time to recovery, and EQ-5D), while controlling for patient characteristics (self-reported symptom severity, comorbidities, and health-related quality of life) at first attendance. Results POCCRP testing is associated with non-significant positive reductions in antibiotic prescribing (P = 0.078) and increased cost (P = 0.092). Despite the uncertainty, POCCRP testing is also associated with a cost per quality-adjusted life year (QALY) gain of €9391. At a willingness-to-pay threshold of €30 000 per QALY gained, there is a 70% probability of CRP being cost-effective. Conclusion POCCRP testing is likely to provide a cost-effective diagnostic intervention both in terms of reducing antibiotic prescribing and in terms of QALYs gained. PMID:23834883

  15. Cost-effectiveness of population based BRCA testing with varying Ashkenazi Jewish ancestry.

    Science.gov (United States)

    Manchanda, Ranjit; Patel, Shreeya; Antoniou, Antonis C; Levy-Lahad, Ephrat; Turnbull, Clare; Evans, D Gareth; Hopper, John L; Macinnis, Robert J; Menon, Usha; Jacobs, Ian; Legood, Rosa

    2017-11-01

    Population-based BRCA1/BRCA2 testing has been found to be cost-effective compared with family history-based testing in Ashkenazi-Jewish women were >30 years old with 4 Ashkenazi-Jewish grandparents. However, individuals may have 1, 2, or 3 Ashkenazi-Jewish grandparents, and cost-effectiveness data are lacking at these lower BRCA prevalence estimates. We present an updated cost-effectiveness analysis of population BRCA1/BRCA2 testing for women with 1, 2, and 3 Ashkenazi-Jewish grandparents. Decision analysis model. Lifetime costs and effects of population and family history-based testing were compared with the use of a decision analysis model. 56% BRCA carriers are missed by family history criteria alone. Analyses were conducted for United Kingdom and United States populations. Model parameters were obtained from the Genetic Cancer Prediction through Population Screening trial and published literature. Model parameters and BRCA population prevalence for individuals with 3, 2, or 1 Ashkenazi-Jewish grandparent were adjusted for the relative frequency of BRCA mutations in the Ashkenazi-Jewish and general populations. Incremental cost-effectiveness ratios were calculated for all Ashkenazi-Jewish grandparent scenarios. Costs, along with outcomes, were discounted at 3.5%. The time horizon of the analysis is "life-time," and perspective is "payer." Probabilistic sensitivity analysis evaluated model uncertainty. Population testing for BRCA mutations is cost-saving in Ashkenazi-Jewish women with 2, 3, or 4 grandparents (22-33 days life-gained) in the United Kingdom and 1, 2, 3, or 4 grandparents (12-26 days life-gained) in the United States populations, respectively. It is also extremely cost-effective in women in the United Kingdom with just 1 Ashkenazi-Jewish grandparent with an incremental cost-effectiveness ratio of £863 per quality-adjusted life-years and 15 days life gained. Results show that population-testing remains cost-effective at the £20,000-30000 per quality

  16. Human Health Risk Assessment of Pharmaceuticals in Water: Issues and Challenges Ahead

    Directory of Open Access Journals (Sweden)

    Arun Kumar

    2010-11-01

    Full Text Available This study identified existing issues related to quantitative pharmaceutical risk assessment (QPhRA, hereafter for pharmaceuticals in water and proposed possible solutions by analyzing methodologies and findings of different published QPhRA studies. Retrospective site-specific QPhRA studies from different parts of the world (U.S.A., United Kingdom, Europe, India, etc. were reviewed in a structured manner to understand different assumptions, outcomes obtained and issues, identified/addressed/raised by the different QPhRA studies. Till date, most of the published studies have concluded that there is no appreciable risk to human health during environmental exposures of pharmaceuticals; however, attention is still required to following identified issues: (1 Use of measured versus predicted pharmaceutical concentration, (2 Identification of pharmaceuticals-of-concern and compounds needing special considerations, (3 Use of source water versus finished drinking water-related exposure scenarios, (4 Selection of representative exposure routes, (5 Valuation of uncertainty factors, and (6 Risk assessment for mixture of chemicals. To close the existing data and methodology gaps, this study proposed possible ways to address and/or incorporation these considerations within the QPhRA framework; however, more research work is still required to address issues, such as incorporation of short-term to long-term extrapolation and mixture effects in the QPhRA framework. Specifically, this study proposed a development of a new “mixture effects-related uncertainty factor” for mixture of chemicals (i.e., mixUFcomposite, similar to an uncertainty factor of a single chemical, within the QPhRA framework. In addition to all five traditionally used uncertainty factors, this uncertainty factor is also proposed to include concentration effects due to presence of different range of concentration levels of pharmaceuticals in a mixture. However, further work is required to

  17. Pharmaceuticals: pharmaceutical cost controls--2005. End of Year Issue Brief.

    Science.gov (United States)

    Seay, Melicia; Varma, Priya

    2005-12-31

    The enactment of the Omnibus Budget Reconciliation Act of 1990 (OBRA '90) gave states the option of offering pharmaceutical benefits within their Medicaid programs. But the law placed restrictions on states' flexibility to control what prescriptions they would cover and required the states to reimburse outpatient prescription drugs from manufacturers that signed rebate agreements with the U.S. Department of Health and Human Services. Forty-nine states--Arizona is excluded, based on its program structure--and the District of Columbia currently offer prescription drug coverage under the Medicaid Drug Rebate Program. During the past four years, states all over the country have been plagued with revenue shortfalls in their state Medicaid budgets. While the fiscal situation improved for most states in the 2004 legislative session, many states still face budget pressures in 2005. Compounding existing budget pressures are threats from the Bush Administration to shift increased costs of the Medicaid program on to the states. All things considered, the economic pressure of funding Medicaid is at the top of legislative agendas in 2005. As in previous years, states are attempting to reduce costs to their Medicaid programs by seeking savings in their pharmaceutical programs. Prescription drug costs are highly attributed as a contributing factor to the fiscal climate of state Medicaid programs. Currently, prescription drug spending outpaces that of every other category of health care and drug prices are rising faster than inflation. In response, states are instituting a variety of pharmaceutical cost control measures such as creating preferred drug lists (PDLs), negotiating supplemental rebates, forming bulk purchasing pools, promoting generic drug substitution and implementing price controls. As prescription drug cost containment tools have gained acceptance and momentum, they continue to be controversial. This issue brief explores the debate, history, methodology, utilization

  18. Information Synthesis in Uncertainty Studies: Application to the Analysis of the BEMUSE Results

    International Nuclear Information System (INIS)

    Baccou, J.; Chojnacki, E.; Destercke, S.

    2013-01-01

    mathematical framework, the more time consuming the propagation should be. Therefore, the key point is here to construct a numerical treatment for uncertainty propagation which reduces the computational cost and can be applied to complex models used in practice. In nuclear safety studies, different uncertainty analyses using different codes and implying different experts are generally performed. Deriving benefits from these analyses appears to be a problem of information synthesis which is the third key issue. Indeed each uncertainty study can be viewed as an information source on quantities of interest. It is then useful to define formal methods to combine all these information sources in order to improve the reliability of the results and to detect possible conflicts (if any) between the sources. The efficiency of an uncertainty analysis requires a reliable quantification of the information associated to uncertainty sources. This quantification is addressed in the fourth key issue. It consists in exploiting the information related to available experiments and to the comparison code/experiment to infer the uncertainty attached to the code input parameters. Therefore, the crucial points stand in the choice of an experimental database sufficiently representative and exhaustive of the considered phenomenon and in the construction of an efficient treatment to perform this inference. The two first points have been deeply studied in the frame of the OECD BEMUSE Program. In particular, it came out that statistical approaches, based on Monte-Carlo techniques, are now sufficiently robust for the evaluation of uncertainty on a LB-LOCA transient. In this paper, we focus on the third issue and present some recent developments proposed by IRSN to derive formal tools in order to improve the reliability of an analysis involving different information sources. It is applied to exhibit some important conclusions from the two BEMUSE benchmarks. For sake of completeness, we recall that the last

  19. Uncertainty, joint uncertainty, and the quantum uncertainty principle

    International Nuclear Information System (INIS)

    Narasimhachar, Varun; Poostindouz, Alireza; Gour, Gilad

    2016-01-01

    Historically, the element of uncertainty in quantum mechanics has been expressed through mathematical identities called uncertainty relations, a great many of which continue to be discovered. These relations use diverse measures to quantify uncertainty (and joint uncertainty). In this paper we use operational information-theoretic principles to identify the common essence of all such measures, thereby defining measure-independent notions of uncertainty and joint uncertainty. We find that most existing entropic uncertainty relations use measures of joint uncertainty that yield themselves to a small class of operational interpretations. Our notion relaxes this restriction, revealing previously unexplored joint uncertainty measures. To illustrate the utility of our formalism, we derive an uncertainty relation based on one such new measure. We also use our formalism to gain insight into the conditions under which measure-independent uncertainty relations can be found. (paper)

  20. Evaluation method for uncertainty of effective delayed neutron fraction βeff

    International Nuclear Information System (INIS)

    Zukeran, Atsushi

    1999-01-01

    Uncertainty of effective delayed neutron fraction β eff is evaluated in terms of three quantities; uncertainties of the basic delayed neutron constants, energy dependence of delayed neutron yield ν d m , and the uncertainties of the fission cross sections of fuel elements. The uncertainty of β eff due to the delayed neutron yield is expressed by a linearized formula assuming that the delayed neutron yield does not depend on the incident energy, and the energy dependence is supplemented by using the detailed energy dependence proposed by D'Angelo and Filip. The third quantity, uncertainties of fission cross section, is evaluated on the basis of the generalized perturbation theory in relation to reaction rate rations such as central spectral indexes or average reaction rate ratios. Resultant uncertainty of β eff is about 4 to 5%s, in which primary factor is the delayed neutron yield, and the secondary one is the fission cross section uncertainty, especially for 238 U. The energy dependence of ν d m systematically reduces the magnitude of β eff about 1.4% to 1.7%, depending on the model of the energy vs. ν d m correlation curve. (author)

  1. Identifying potentially cost effective chronic care programs for people with COPD

    Directory of Open Access Journals (Sweden)

    L M G Steuten

    2008-12-01

    uncertainty.Keywords: chronic care management, COPD, cost-effectiveness, review

  2. Cost-Effectiveness of Rotavirus Vaccination in France-Accounting for Indirect Protection.

    Science.gov (United States)

    Yamin, Dan; Atkins, Katherine E; Remy, Vanessa; Galvani, Alison P

    Vaccination against rotavirus has shown great potential for reducing the primary cause of severe childhood gastroenteritis. Previous economic evaluations of rotavirus vaccination in France have not modeled the potential impact of vaccines on disease burden via reduced transmission. To determine the cost-effectiveness of the introduction of pentavalent rotavirus vaccination into the French infant vaccination schedule. We developed an age-structured model of rotavirus transmission calibrated to 6 years of French gastroenteritis incidence and vaccine clinical trial data. We evaluated the cost-effectiveness of pentavalent rotavirus vaccination considering that 75% of infants would receive the three-dose vaccine course. Our model predicts that rotavirus vaccination will decrease rotavirus gastroenteritis incidence and associated clinical outcomes in vaccinated and unvaccinated individuals, delay the seasonal peak of infection, and increase the age of infection. From the societal perspective, our base-case scenario predicts that vaccination coverage would be cost-effective at €115 or €135 per vaccine course at €28,500 and €39,500/quality-adjusted life-year (QALY) gained, respectively, and suggests that almost 95% of the financial benefits will be recouped within the first 5 years following vaccination implementation. From the third-party payer perspective, incremental cost-effectiveness ratios ranged from €12,500 to €20,000/QALY, respectively. Our uncertainty analysis suggests that findings were sensitive to various assumptions including the number of hospitalizations, outpatient visits, and the extent of QALY losses per rotavirus episode. Introducing pentavalent rotavirus vaccination into the French infant vaccination schedule would significantly reduce the burden of rotavirus disease in children, and could be cost-effective under plausible conditions. Copyright © 2016 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by

  3. Uncertainty characterization approaches for risk assessment of DBPs in drinking water: a review.

    Science.gov (United States)

    Chowdhury, Shakhawat; Champagne, Pascale; McLellan, P James

    2009-04-01

    The management of risk from disinfection by-products (DBPs) in drinking water has become a critical issue over the last three decades. The areas of concern for risk management studies include (i) human health risk from DBPs, (ii) disinfection performance, (iii) technical feasibility (maintenance, management and operation) of treatment and disinfection approaches, and (iv) cost. Human health risk assessment is typically considered to be the most important phase of the risk-based decision-making or risk management studies. The factors associated with health risk assessment and other attributes are generally prone to considerable uncertainty. Probabilistic and non-probabilistic approaches have both been employed to characterize uncertainties associated with risk assessment. The probabilistic approaches include sampling-based methods (typically Monte Carlo simulation and stratified sampling) and asymptotic (approximate) reliability analysis (first- and second-order reliability methods). Non-probabilistic approaches include interval analysis, fuzzy set theory and possibility theory. However, it is generally accepted that no single method is suitable for the entire spectrum of problems encountered in uncertainty analyses for risk assessment. Each method has its own set of advantages and limitations. In this paper, the feasibility and limitations of different uncertainty analysis approaches are outlined for risk management studies of drinking water supply systems. The findings assist in the selection of suitable approaches for uncertainty analysis in risk management studies associated with DBPs and human health risk.

  4. Combining Time-Driven Activity-Based Costing with Clinical Outcome in Cost-Effectiveness Analysis to Measure Value in Treatment of Depression.

    Directory of Open Access Journals (Sweden)

    Samir El Alaoui

    Full Text Available A major challenge of mental health care is to provide safe and effective treatment with limited resources. The main purpose of this study was to examine a value-based approach in clinical psychiatry when evaluating a process improvement initiative. This was accomplished by using the relatively new time driven activity based costing (TDABC method within the more widely adopted cost-effectiveness analysis framework for economic evaluation of healthcare technologies. The objective was to evaluate the cost-effectiveness of allowing psychologists to perform post-treatment assessment previously performed by psychiatrists at an outpatient clinic treating depression using internet-based cognitive-behavioral therapy (ICBT.Data was collected from 568 adult patients treated with ICBT for depression during 2013-2014. The TDABC methodology was used to estimate total healthcare costs, including development of process maps for the complete cycle of care and estimation of resource use and minute costs of staff, hospital space and materials based on their relative proportions used. Clinical outcomes were measured using the Patient Health Questionnaire depression scale (PHQ-9 before and after treatment and at 6-month follow-up. Cost-effectiveness analyses (CEA was performed and the results presented as incremental net benefits (INB, cost-effectiveness acceptability curves (CEACs and confidence ellipses to demonstrate uncertainty around the value of the organizational intervention.Taking into account the complete healthcare process (from referral to follow-up assessment, treatment costs decreased from $709 (SD = $130 per patient in 2013 to $659 (SD = $134 in 2014 while treatment effectiveness was maintained; 27% had achieved full remission from depression after treatment (PHQ-9 < 5 during both 2013 and 2014 and an additional 35% and 33% had achieved partial remission in 2013 and 2014, respectively. At follow-up, 42% were in full remission after treatment during

  5. Severe accident issue resolution -- definition and perspective

    International Nuclear Information System (INIS)

    Harper, F.T.

    1995-01-01

    The purpose of this discussion is to introduce the session on the Progress on the Resolution of Severe Accident Issues. There has been much work in the area of resolution of severe accident issues over the past few years. This work has been focused on those issues most important to risk as assessed by comprehensive studies such as NUREG-1150. In particular, issues associated with early containment failure have been analyzed. These efforts to resolve issues have been hampered by the fact that open-quotes issue resolutionclose quotes has not always been well defined. The term open-quotes issue resolutionclose quotes conjures tip different images for the regulator, the accident analyst, the physicist, and the probabalist. In fact it is common to have as many different images of issue resolution as there are people in the room. This issue is complicated by the fact that the uncertainty in severe accident issues is enormous. (When convolved, the quantitative uncertainty in an integrated analysis due to severe accident issues can span several orders of magnitude.) In this summary, hierarchy is presented in an attempt to add some perspective to the resolution of issues in the face of large uncertainties. Recommendations are also made for analysts communicating in the area of issue resolution

  6. Cost, cost-efficiency and cost-effectiveness of integrated family planning and HIV services.

    Science.gov (United States)

    Shade, Starley B; Kevany, Sebastian; Onono, Maricianah; Ochieng, George; Steinfeld, Rachel L; Grossman, Daniel; Newmann, Sara J; Blat, Cinthia; Bukusi, Elizabeth A; Cohen, Craig R

    2013-10-01

    To evaluate costs, cost-efficiency and cost-effectiveness of integration of family planning into HIV services. Integration of family planning services into HIV care and treatment clinics. A cluster-randomized trial. Twelve health facilities in Nyanza, Kenya were randomized to integrate family planning into HIV care and treatment; six health facilities were randomized to (nonintegrated) standard-of-care with separately delivered family planning and HIV services. We assessed costs, cost-efficiency (cost per additional use of more effective family planning), and cost-effectiveness (cost per pregnancy averted) associated with the first year of integration of family planning into HIV care. More effective family planning methods included oral and injectable contraceptives, subdermal implants, intrauterine device, and female and male sterilization. We collected cost data through interviews with study staff and review of financial records to determine costs of service integration. Integration of services was associated with an average marginal cost of $841 per site and $48 per female patient. Average overall and marginal costs of integration were associated with personnel costs [initial ($1003 vs. $872) and refresher ($498 vs. $330) training, mentoring ($1175 vs. $902) and supervision ($1694 vs. $1636)], with fewer resources required for other fixed ($18 vs. $0) and recurring expenses ($471 vs. $287). Integration was associated with a marginal cost of $65 for each additional use of more effective family planning and $1368 for each pregnancy averted. Integration of family planning and HIV services is feasible, inexpensive to implement, and cost-efficient in the Kenyan setting, and thus supports current Kenyan integration policy.

  7. The cost-effectiveness of group cognitive behavioral therapy compared with routine primary care for women with postnatal depression in the UK.

    Science.gov (United States)

    Stevenson, Matt D; Scope, Alison; Sutcliffe, Paul A

    2010-08-01

    To assess the cost-effectiveness of group cognitive behavior therapy (gCBT) in comparison with routine primary care for women with postnatal depression in the UK. Our analysis was based on a systematic literature review of the relative clinical effectiveness of gCBT compared with routine primary care and further reviews, supplemented with expert opinion of the likely cost of providing gCBT and the duration of comparative advantage for gCBT. Raw data were used to estimate a statistical relationship between changes in the Edinburgh Postnatal Depression Score (EPDS) values and changes in short-form six dimensions' (SF-6D) values. A mathematical model was constructed, and probabilistic sensitivity analyses were undertaken to estimate the mean cost per quality-adjusted life-year (QALY) and to evaluate the expected value of perfect information (EVPI). The mean cost per QALY from the stochastic analysis was estimated to be pound36,062; however, there was considerable uncertainty around this value. The EVPI was estimated to be greater than pound64 million; the key uncertainties were in the cost per woman of providing treatment and in the statistical relationship between changes in EPDS values and changes in SF-6D values. The expected value of perfect partial information for both of these parameters was in excess of pound25 million. Given the current information, the use of gCBT does not appear to be cost-effective; however, this decision is uncertain. The value of information analyses conducted indicates that further research to provide robust information on key parameters is needed and appears justified in cost-effective terms.

  8. Assessing framing of uncertainties in water management practice

    NARCIS (Netherlands)

    Isendahl, N.; Dewulf, A.; Brugnach, M.; Francois, G.; Möllenkamp, S.; Pahl-Wostl, C.

    2009-01-01

    Dealing with uncertainties in water management is an important issue and is one which will only increase in light of global changes, particularly climate change. So far, uncertainties in water management have mostly been assessed from a scientific point of view, and in quantitative terms. In this

  9. Leverage effect, economic policy uncertainty and realized volatility with regime switching

    Science.gov (United States)

    Duan, Yinying; Chen, Wang; Zeng, Qing; Liu, Zhicao

    2018-03-01

    In this study, we first investigate the impacts of leverage effect and economic policy uncertainty (EPU) on future volatility in the framework of regime switching. Out-of-sample results show that the HAR-RV including the leverage effect and economic policy uncertainty with regimes can achieve higher forecast accuracy than RV-type and GARCH-class models. Our robustness results further imply that these factors in the framework of regime switching can substantially improve the HAR-RV's forecast performance.

  10. Cost-effectiveness thresholds in health care: a bookshelf guide to their meaning and use.

    Science.gov (United States)

    Culyer, Anthony J

    2016-10-01

    There is misunderstanding about both the meaning and the role of cost-effectiveness thresholds in policy decision making. This article dissects the main issues by use of a bookshelf metaphor. Its main conclusions are as follows: it must be possible to compare interventions in terms of their impact on a common measure of health; mere effectiveness is not a persuasive case for inclusion in public insurance plans; public health advocates need to address issues of relative effectiveness; a 'first best' benchmark or threshold ratio of health gain to expenditure identifies the least effective intervention that should be included in a public insurance plan; the reciprocal of this ratio - the 'first best' cost-effectiveness threshold - will rise or fall as the health budget rises or falls (ceteris paribus); setting thresholds too high or too low costs lives; failure to set any cost-effectiveness threshold at all also involves avertable deaths and morbidity; the threshold cannot be set independently of the health budget; the threshold can be approached from either the demand side or the supply side - the two are equivalent only in a health-maximising equilibrium; the supply-side approach generates an estimate of a 'second best' cost-effectiveness threshold that is higher than the 'first best'; the second best threshold is the one generally to be preferred in decisions about adding or subtracting interventions in an established public insurance package; multiple thresholds are implied by systems having distinct and separable health budgets; disinvestment involves eliminating effective technologies from the insured bundle; differential weighting of beneficiaries' health gains may affect the threshold; anonymity and identity are factors that may affect the interpretation of the threshold; the true opportunity cost of health care in a community, where the effectiveness of interventions is determined by their impact on health, is not to be measured in money - but in health

  11. Modeling the cost-effectiveness of infant vaccination with pneumococcal conjugate vaccines in Germany.

    Science.gov (United States)

    Kuhlmann, Alexander; von der Schulenburg, J-Matthias Graf

    2017-04-01

    In 2009, the European Medicines Agency granted approval for two higher-valent pneumococcal conjugate vaccines. This study aims to evaluate the cost-effectiveness of universal infant (historical vaccination scheme in infants as well as indirect herd effects and replacement disease. We used German epidemiological data to calculate episodes of IPD, PNE, and AOM, as well as direct and indirect effects of the vaccination. Parameter uncertainty was tested in univariate and probabilistic sensitivity analyses. In the base-case analysis, the ICER of PCV13 versus PCV10 infant vaccination was EUR 9826 per quality-adjusted life-year (QALY) gained or EUR 5490 per life-year (LY) gained from the societal perspective and EUR 3368 per QALY gained or EUR 1882 per LY gained from the perspective of the German statutory health insurance. The results were particularly sensitive to the magnitude of indirect effects of both vaccines. Universal infant vaccination with PCV13 is likely to be a cost-effective intervention compared with PCV10 within the German health care system, if additional net indirect effects of PCV13 vaccination are significant.

  12. Nuclear energy: the real cost. A special report

    Energy Technology Data Exchange (ETDEWEB)

    Spencer, K.; Marshall, R.; Sweet, C.; Prior, M.; Welsh, I.; Bunyard, P.; Goldsmith, E.; Hildyard, N.; Jeffery, J.W. (Committee for the Study of the Economics of Nuclear Electricity, Camelford (UK))

    1981-12-01

    This report on the discussions within a small group of academics falls under the headings: chairman's foreword; summary and recommendations; the government's nuclear power programme and its implications; the CEGB's planning record; the past performance of Britain's nuclear power stations - a guide for the future (query); nuclear power -early uncertainties; historic costs - 'the fraud inherent in all inflationary finance'; current cost accounting; fuel costs - coal stays steady, nuclear rises; net effective cost and the rationale for nuclear power; reinterpreting net effective costs; other considerations; conclusions and recommendations; references.

  13. Cost-effectiveness of annual versus biennial screening mammography for women with high mammographic breast density.

    Science.gov (United States)

    Pataky, Reka; Ismail, Zahra; Coldman, Andrew J; Elwood, Mark; Gelmon, Karen; Hedden, Lindsay; Hislop, Greg; Kan, Lisa; McCoy, Bonnie; Olivotto, Ivo A; Peacock, Stuart

    2014-12-01

    The sensitivity of screening mammography is much lower among women who have dense breast tissue, compared with women who have largely fatty breasts, and they are also at much higher risk of developing the disease. Increasing mammography screening frequency from biennially to annually has been suggested as a policy option to address the elevated risk in this population. The purpose of this study was to assess the cost-effectiveness of annual versus biennial screening mammography among women aged 50-79 with dense breast tissue. A Markov model was constructed based on screening, diagnostic, and treatment pathways for the population-based screening and cancer care programme in British Columbia, Canada. Model probabilities and screening costs were calculated from screening programme data. Costs for breast cancer treatment were calculated from treatment data, and utility values were obtained from the literature. Incremental cost-effectiveness was expressed as cost per quality adjusted life year (QALY), and probabilistic sensitivity analysis was conducted. Compared with biennial screening, annual screening generated an additional 0.0014 QALYs (95% CI: -0.0480-0.0359) at a cost of $819 ($ = Canadian dollars) per patient (95% CI: 506-1185), resulting in an incremental cost effectiveness ratio of $565,912/QALY. Annual screening had a 37.5% probability of being cost-effective at a willingness-to-pay threshold of $100,000/QALY. There is considerable uncertainty about the incremental cost-effectiveness of annual mammography. Further research on the comparative effectiveness of screening strategies for women with high mammographic breast density is warranted, particularly as digital mammography and density measurement become more widespread, before cost-effectiveness can be reevaluated. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  14. Improving cost-effectiveness and facilitating participation of developing countries in international emissions trading

    International Nuclear Information System (INIS)

    Bohm, P.

    2003-01-01

    Cost-effectiveness is a crucial requirement for meaningful agreements on international climate change policy. This is also borne out in the wording of the Framework Convention of Climate Change and, in particular, the Kyoto Protocol (KP), see UNFCCC (1992) and UN (1997). However, the KP - as it stands after COP7 in Marrakech - is not fully cost-effective, although it may eventually turn out to be the only politically feasible, 'most cost-effective', first step in international climate change policy. The successor to the COP7 version of the KP may be a renegotiated protocol, if the COP7 version fails to be ratified by enough countries to enter into force, or it may be the treaty to be designed for a second commitment period. Four dimensions in which cost-effectiveness may be improved in a treaty that succeeds the KP are discussed here. They all relate to international emissions trading (IET) which is likely to be the most significant instrument for attaining cost-effective reductions in aggregate greenhouse gas (GHG) emissions. It is important for a climate treaty to be able to attract as many developing countries to IET as possible and achieve this as soon as possible. This would have to occur at essentially no cost to them. Only with developing countries onboard can the world community get full access to their low-cost options for emission reductions. A first aspect to be discussed here is related to identifying a cost-effective approach to attain that goal (Section 1). Another aspect concerns the role of the Clean Development Mechanism (CDM) in this context (Section 2). A third issue is to evaluate the consequences for cost-effectiveness of introducing a Commitment Period Reserve to limit 'overselling' (Section 3). A final one deals with the increase in flexibility that would follow from allowing not only banking but also borrowing of Assigned Amount Units (AAUs) (Section 4). While the first two issues refer directly to developing countries, the last two will be

  15. Bi-Objective Optimal Control Modification Adaptive Control for Systems with Input Uncertainty

    Science.gov (United States)

    Nguyen, Nhan T.

    2012-01-01

    This paper presents a new model-reference adaptive control method based on a bi-objective optimal control formulation for systems with input uncertainty. A parallel predictor model is constructed to relate the predictor error to the estimation error of the control effectiveness matrix. In this work, we develop an optimal control modification adaptive control approach that seeks to minimize a bi-objective linear quadratic cost function of both the tracking error norm and predictor error norm simultaneously. The resulting adaptive laws for the parametric uncertainty and control effectiveness uncertainty are dependent on both the tracking error and predictor error, while the adaptive laws for the feedback gain and command feedforward gain are only dependent on the tracking error. The optimal control modification term provides robustness to the adaptive laws naturally from the optimal control framework. Simulations demonstrate the effectiveness of the proposed adaptive control approach.

  16. The Cost-Effectiveness of Lowering Permissible Noise Levels Around U.S. Airports

    Directory of Open Access Journals (Sweden)

    Boshen Jiao

    2017-12-01

    Full Text Available Aircraft noise increases the risk of cardiovascular diseases and mental illness. The allowable limit for sound in the vicinity of an airport is 65 decibels (dB averaged over a 24-h ‘day and night’ period (DNL in the United States. We evaluate the trade-off between the cost and the health benefits of changing the regulatory DNL level from 65 dB to 55 dB using a Markov model. The study used LaGuardia Airport (LGA as a case study. In compliance with 55 dB allowable limit of aircraft noise, sound insulation would be required for residential homes within the 55 dB to 65 dB DNL. A Markov model was built to assess the cost-effectiveness of installing sound insulation. One-way sensitivity analyses and Monte Carlo simulation were conducted to test uncertainty of the model. The incremental cost-effectiveness ratio of installing sound insulation for residents exposed to airplane noise from LGA was $11,163/QALY gained (95% credible interval: cost-saving and life-saving to $93,054/QALY gained. Changing the regulatory standard for noise exposure around airports from 65 dB to 55 dB comes at a very good value.

  17. Cost-effective framework for basic surgical skills training.

    Science.gov (United States)

    Jiang, Deng-Jin; Wen, Chan; Yang, Ai-Jun; Zhu, Zhi-Li; Lei, Yan; Lan, Yang-Jun; Huang, Qing-Yuan; Hou, Xiao-Yu

    2013-06-01

    The importance of basic surgical skills is entirely agreed among surgical educators. However, restricted by ethical issues, finance etc, the basic surgical skills training is increasingly challenged. Increasing cost gives an impetus to the development of cost-effective training models to meet the trainees' acquisition of basic surgical skills. In this situation, a cost-effective training framework was formed in our department and introduced here. Each five students were assigned to a 'training unit'. The training was implemented weekly for 18 weeks. The framework consisted of an early, a transitional, an integrative stage and a surgical skills competition. Corresponding training modules were selected and assembled scientifically at each stage. The modules comprised campus intranet databases, sponge benchtop, nonliving animal tissue, local dissection specimens and simulating reality operations. The training outcomes used direct observation of procedural skills as an assessment tool. The training data of 50 trainees who were randomly selected in each year from 2006 to 2011 year, were retrospectively analysed. An excellent and good rate of the surgical skills is from 82 to 88%, but there is no significant difference among 6 years (P > 0.05). The skills scores of the contestants are markedly higher than those of non-contestants (P < 0.05). The average training cost per trainee is about $21.85-34.08. The present training framework is reliable, feasible, repeatable and cost-effective. The skills competition can promote to improve the surgical skills level of trainees. © 2012 The Authors. ANZ Journal of Surgery © 2012 Royal Australasian College of Surgeons.

  18. Effect of Uncertainty Parameters in Blowdown and Reflood Models for OPR1000 LBLOCA Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Huh, Byung Gil; Jin, Chang Yong; Seul, Kwangwon; Hwang, Taesuk [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2014-05-15

    KINS(Korea Institute of Nuclear Safety) has also performed the audit calculation with the KINS Realistic Evaluation Methodology(KINS-REM) to confirm the validity of licensee's calculation. In the BEPU method, it is very important to quantify the code and model uncertainty. It is referred in the following requirement: BE calculations in Regulatory Guide 1.157 - 'the code and models used are acceptable and applicable to the specific facility over the intended operating range and must quantify the uncertainty in the specific application'. In general, the uncertainty of model/code should be obtained through the data comparison with relevant integral- and separate-effect tests at different scales. However, it is not easy to determine these kinds of uncertainty because of the difficulty for evaluating accurately various experiments. Therefore, the expert judgment has been used in many cases even with the limitation that the uncertainty range of important parameters can be wide and inaccurate. In the KINS-REM, six heat transfer parameters in the blowdown phase have been used to consider the uncertainty of models. Recently, MARS-KS code was modified to consider the uncertainty of the five heat transfer parameters in the reflood phase. Accordingly, it is required that the uncertainty range for parameters of reflood models is determined and the effect of these ranges is evaluated. In this study, the large break LOCA (LBLOCA) analysis for OPR1000 was performed to identify the effect of uncertainty parameters in blowdown and reflood models.

  19. Incorporating the effects of socioeconomic uncertainty into priority setting for conservation investment.

    Science.gov (United States)

    McBride, Marissa F; Wilson, Kerrie A; Bode, Michael; Possingham, Hugh P

    2007-12-01

    Uncertainty in the implementation and outcomes of conservation actions that is not accounted for leaves conservation plans vulnerable to potential changes in future conditions. We used a decision-theoretic approach to investigate the effects of two types of investment uncertainty on the optimal allocation of global conservation resources for land acquisition in the Mediterranean Basin. We considered uncertainty about (1) whether investment will continue and (2) whether the acquired biodiversity assets are secure, which we termed transaction uncertainty and performance uncertainty, respectively. We also developed and tested the robustness of different rules of thumb for guiding the allocation of conservation resources when these sources of uncertainty exist. In the presence of uncertainty in future investment ability (transaction uncertainty), the optimal strategy was opportunistic, meaning the investment priority should be to act where uncertainty is highest while investment remains possible. When there was a probability that investments would fail (performance uncertainty), the optimal solution became a complex trade-off between the immediate biodiversity benefits of acting in a region and the perceived longevity of the investment. In general, regions were prioritized for investment when they had the greatest performance certainty, even if an alternative region was highly threatened or had higher biodiversity value. The improved performance of rules of thumb when accounting for uncertainty highlights the importance of explicitly incorporating sources of investment uncertainty and evaluating potential conservation investments in the context of their likely long-term success.

  20. Transportation Energy Futures Series: Non-Cost Barriers to Consumer Adoption of New Light-Duty Vehicle Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Stephens, T.

    2013-03-01

    Consumer preferences are key to the adoption of new vehicle technologies. Barriers to consumer adoption include price and other obstacles, such as limited driving range and charging infrastructure; unfamiliarity with the technology and uncertainty about direct benefits; limited makes and models with the technology; reputation or perception of the technology; standardization issues; and regulations. For each of these non-cost barriers, this report estimates an effective cost and summarizes underlying influences on consumer preferences, approximate magnitude and relative severity, and assesses potential actions, based on a comprehensive literature review. While the report concludes that non-cost barriers are significant, effective cost and potential market share are very uncertain. Policies and programs including opportunities for drivers to test drive advanced vehicles, general public outreach and information programs, incentives for providing charging and fueling infrastructure, and development of technology standards were examined for their ability to address barriers, but little quantitative data exists on the effectiveness of these measures. This is one in a series of reports produced as a result of the Transportation Energy Futures project, a Department of Energy-sponsored multi-agency effort to pinpoint underexplored strategies for reducing GHGs and petroleum dependence related to transportation.