Competitive electricity markets: One size should fit all

Energy Technology Data Exchange (ETDEWEB)

Ruff, L.E.

1999-11-01

Various market models have been used to try to create competition in the electricity industry in various parts of the world, with varying degrees of success. But every electricity market that has produced reasonably effective and efficient competition has been based on some version of the same generic model. And most of the problems encountered by these markets--apart from problems due to structural flaws such as too few competitors--can be attributed to inconsistent or incomplete application of this basic model concept. In this sense, one size of market model really does fit all--or at least one size should fit all if the objective is to create effective and efficient competition for the benefit of consumers. Effort to slow or reverse the movement to an open spot market integrated with physical dispatch will create complexities and inefficiencies that benefit oligopolists and middlemen at the expense of smaller producers and final consumers.

ESTIMATING RISK ON THE CAPITAL MARKET WITH VaR METHOD

Directory of Open Access Journals (Sweden)

Sinisa Bogdan

2015-06-01

Full Text Available The two basic questions that every investor tries to answer before investment are questions about predicting return and risk. Risk and return are generally considered two positively correlated sizes, during the growth of risk it is expected increase of return to compensate the higher risk. The quantification of risk in the capital market represents the current topic since occurrence of securities. Together with estimated future returns it represents starting point of any investment. In this study it is described the history of the emergence of VaR methods, usefulness in assessing the risks of financial assets. Three main Value at Risk (VaR methodologies are decribed and explained in detail: historical method, parametric method and Monte Carlo method. After the theoretical review of VaR methods it is estimated risk of liquid stocks and portfolio from the Croatian capital market with historical and parametric VaR method, after which the results were compared and explained.

Illegal markets: Estimates of global proceeds

Directory of Open Access Journals (Sweden)

Marinković Darko M.

2015-01-01

Full Text Available Illegal markets represent a phenomenon of considerable economic, political and social significance whose annual income exceeds the value of a thousand billion USD. Illegal market participants are beyond the reach of government institutions and rule of law while social connections and personal acquaintances play an important role of functional substitute. In the last decade there was a significant increase of illegal trafficking of narcotics, people, fire arms, counterfeit products and natural resources. Both selling and purchase of these as well as other kinds of products and services at illegal markets are generally characterized by high level of organization and presence of strong criminal groups and networks. Although these activities existed in the past their present scope and geographic distribution are without precedent. Measuring unlawful financial flows at illegal markets represents quite a complex task. Various estimates are the result of inexistence of uniform and generally accepted methodology. In addition to this, the special problem is also the consensus of market actors, because of which the phenomenon of illegal markets and distribution of products and services at these markets is rather hidden. The paper defines and analyzes the key features of illegal markets, the role of organized crime at illegal markets, as well as the estimates of the values of financial flows at the markets of counterfeit products, narcotics, and people as goods, or human organs and sexual services, weapons, tobacco products and dirty money.

Export Marketing Involvement of African Small and Medium Size ...

African Journals Online (AJOL)

Export Marketing Involvement of African Small and Medium Size Enterprises: Tanzania's Fish Processing Industry. ... This study examined the Export marketing involvement of SMEs from the Least ... EMAIL FULL TEXT EMAIL FULL TEXT

Financial Super-Markets: Size Matters for Asset Trade.

OpenAIRE

Philippe Martin and Hélène Rey.

2000-01-01

This paper presents a new theoretical framework to analyze financial markets in an international context. We build a two-country macroeconomic model in which agents are risk averse, assets are imperfect substitutes, the number of financial assets is endogenous, and cross-border asset trade entails transaction costs. We show that demand effects have important implications for the link between market size, asset prices and financial market development. These effects are consistent with the exis...

Methods for Estimation of Market Power in Electric Power Industry

Science.gov (United States)

Turcik, M.; Oleinikova, I.; Junghans, G.; Kolcun, M.

2012-01-01

The article is related to a topical issue of the newly-arisen market power phenomenon in the electric power industry. The authors point out to the importance of effective instruments and methods for credible estimation of the market power on liberalized electricity market as well as the forms and consequences of market power abuse. The fundamental principles and methods of the market power estimation are given along with the most common relevant indicators. Furthermore, in the work a proposal for determination of the relevant market place taking into account the specific features of power system and a theoretical example of estimating the residual supply index (RSI) in the electricity market are given.

Financial Super-Markets: Size Matters for Asset Trade

OpenAIRE

Philippe Martin; Helene Rey

2001-01-01

This paper presents a new theoretical framework to analyze=20 financial markets in an international context. We build a two-country=20 macroeconomic model in which agents are risk averse, assets are imperfect=20 substitutes, the number of financial assets is endogenous, and cross-border= =20 asset trade entails transaction costs. We show that demand effects have=20 important implications for the link between market size, asset prices and=20 financial market development. These effects are cons...

Estimating Search Engine Index Size Variability

DEFF Research Database (Denmark)

Van den Bosch, Antal; Bogers, Toine; De Kunder, Maurice

2016-01-01

One of the determining factors of the quality of Web search engines is the size of their index. In addition to its influence on search result quality, the size of the indexed Web can also tell us something about which parts of the WWW are directly accessible to the everyday user. We propose a novel...... method of estimating the size of a Web search engine’s index by extrapolating from document frequencies of words observed in a large static corpus of Web pages. In addition, we provide a unique longitudinal perspective on the size of Google and Bing’s indices over a nine-year period, from March 2006...... until January 2015. We find that index size estimates of these two search engines tend to vary dramatically over time, with Google generally possessing a larger index than Bing. This result raises doubts about the reliability of previous one-off estimates of the size of the indexed Web. We find...

Role of Relationship Marketing in Small and Medium-Sized Entreprises

OpenAIRE

Ružica Butigan; Ivana Mahnić

2011-01-01

Along with marketing, small and medium enterprises (SMEs) are commonly associated in literature with relationship marketing which results in marketing networks. This paper examines the specific characteristics that differentiate large companies from small and medium-sized enterprises, and the reasons that prevent SMEs from engaging in traditional marketing within the scope of marketing mix. The paper also shows that the key characteristic which distinguishes small from large companies is a pr...

PRAGMATICS OF USING A MODIFIED CAPM MODEL FOR ESTIMATING COST OF EQUITY ON EMERGING MARKETS

Directory of Open Access Journals (Sweden)

Vitaliy Semenyuk

2016-11-01

Full Text Available The aim of the work is to forming pragmatic recommendations for the development and implementation the modified CAPM model in the process of estimating the equity value on emerging markets. Original CAPM model allows estimating the cost of equity on the developed capital markets. At the same time it requires the information received on the market data basis. But, as show recent empirical research, the classical model does not always produce acceptable results of the equity estimation. In addition, CAPM model in its classical form can’t be used to estimate the cost of equity for countries with emerging markets. This is due with lower efficiency in emerging markets, with lower level of liquidity and capitalization, which makes the information obtained from these markets not entirely reliable. Therefore in practice are increasingly using different modification CAPM models, that allow consider for more specific factors which affect the cost of equity. These factors, which are not considered in the classical CAPM model, include the size of the corporation and country risk. The first factor is actual for developed and emerging markets and needed to account during the equity estimation and modification the CAPM model. Country risk is associated with differences and peculiarities of the economies different countries and in the first place should be taken into account when estimating the cost of equity in emerging capital markets, which are considered by investors as more risky for investment. This factor should also be taken into account in estimating the cost of equity. Methodology In the process of constructing a modified CAPM model, theoretical and methodological provisions were used, which are set out in the work R. Banz, G. Bekaert, M. Goedhart, R. Grabowski, R. Grinold, D. Vessels, A. Damodaran, M. Dempsey, J. Zhang, R. Ibbotson, P. Kaplan, T. Koller, K. Kroner, L. Kruschwitz, M. Long, A. Lofler, G. Mandl, M. Miller, F. Modilyani, K. Nunes, D

Estimating WACC for Regulated Industries on Developing Financial Markets and in Times of Market Uncertainty

Directory of Open Access Journals (Sweden)

Igor Stubelj

2014-03-01

Full Text Available The paper deals with the estimation of weighted average cost of capital (WACC for regulated industries in developing financial markets from the perspective of the current financial-economic crisis. In current financial market situation some evident changes have occurred: risk-free rates in solid and developed financial markets (e. g. USA, Germany have fallen, but due to increased market volatility, the risk premiums have increased. The latter is especially evident in transition economies where the amplitude of market volatility is extremely high. In such circumstances, there is a question of how to calculate WACC properly. WACC is an important measure in financial management decisions and in our case, business regulation. We argue in the paper that the most accurate method for calculating WACC is the estimation of the long-term WACC, which takes into consideration a long-term stable yield of capital and not the current market conditions. Following this, we propose some solutions that could be used for calculating WACC for regulated industries on the developing financial markets in times of market uncertainty. As an example, we present an estimation of the capital cost for a selected Slovenian company, which operates in the regulated industry of electric distribution.

Czech small and medium-sized enterprises and the success in foreign markets

Directory of Open Access Journals (Sweden)

Lenka Procházková

2011-01-01

Full Text Available The importance of small and medium-sized enterprises (SMEs in national economies has been growing. For these reasons, SME’s are paid more attention. The paper deals with the success of Czech SME’s activities in the foreign markets. These enterprises exploited the opportunity of extensive European Union market without internal borders and extended its activities to foreign markets. The objective of this paper is to determine characteristics related to activities carried on by small and medium-sized Czech companies in the foreign markets and then to describe those that fundamentally affect the success of these entities in the foreign markets. The characteristics are divided into five groups (a group of characteristics relating to the company, product, management, international experience and a group of characteristics relating to the target market. The enterprises’ success in foreign markets is assessed by aggregate indicator of success. This indicator is monitored by multi-dimensional indicators of corporate success and evaluation of both objective and subjective. At the last part of the article due to analysis of relationship used, there are identified characteristics affecting the success of Czech small and medium-sized enterprises in foreign markets.

THE METHODS FOR ESTIMATING REGIONAL PROFESSIONAL MOBILE RADIO MARKET POTENTIAL

Directory of Open Access Journals (Sweden)

Y.À. Korobeynikov

2008-12-01

Full Text Available The paper represents the author’s methods of estimating regional professional mobile radio market potential, that belongs to high-tech b2b markets. These methods take into consideration such market peculiarities as great range and complexity of products, technological constraints and infrastructure development for the technological systems operation. The paper gives an estimation of professional mobile radio potential in Perm region. This estimation is already used by one of the systems integrator for its strategy development.

DOE/NASA SIMS Prototype Solar System, no. 4. Part 1: Market analysis. Part 2: Modular manufacturing cost estimate

Science.gov (United States)

1979-01-01

The findings of the IIT Research Institute (IITRI) market study of the SIMS Prototype System 4, a hot water (DHW) system are documented. The feasibility of prepackaging currently available solar heating components into modular subsystems for site assembly is addressed. A documented design and installation procedure and a performance test report were prepared. The potential markets and applications for this particular system in the nonfederal market are profiled by assessing the needs and requirements of potential users and specifiers, by characterizing the nature of the market and the competitive environment, by identifying the barriers to commercial acceptance, and by estimating the size of the potential market.

Evaluation of the Company Size Effect on Latin American Stock Markets

Directory of Open Access Journals (Sweden)

Juan Benjamín Duarte Duarte

2013-11-01

Full Text Available This paper assesses the existence of the size effect on the most important stock markets in Latin America (Argentina, Brazil, Chile, Colombia, Mexico and Peru for the period between 2002 and 2012, using the cross-section contrast methodology of the size effect in the CAPM context. Results show that there is reversed effect in some of the Latin American markets.

A Methodology for Estimating Large-Customer Demand Response MarketPotential

Energy Technology Data Exchange (ETDEWEB)

Goldman, Charles; Hopper, Nicole; Bharvirkar, Ranjit; Neenan,Bernie; Cappers,Peter

2007-08-01

Demand response (DR) is increasingly recognized as an essential ingredient to well-functioning electricity markets. DR market potential studies can answer questions about the amount of DR available in a given area and from which market segments. Several recent DR market potential studies have been conducted, most adapting techniques used to estimate energy-efficiency (EE) potential. In this scoping study, we: reviewed and categorized seven recent DR market potential studies; recommended a methodology for estimating DR market potential for large, non-residential utility customers that uses price elasticities to account for behavior and prices; compiled participation rates and elasticity values from six DR options offered to large customers in recent years, and demonstrated our recommended methodology with large customer market potential scenarios at an illustrative Northeastern utility. We observe that EE and DR have several important differences that argue for an elasticity approach for large-customer DR options that rely on customer-initiated response to prices, rather than the engineering approaches typical of EE potential studies. Base-case estimates suggest that offering DR options to large, non-residential customers results in 1-3% reductions in their class peak demand in response to prices or incentive payments of $500/MWh. Participation rates (i.e., enrollment in voluntary DR programs or acceptance of default hourly pricing) have the greatest influence on DR impacts of all factors studied, yet are the least well understood. Elasticity refinements to reflect the impact of enabling technologies and response at high prices provide more accurate market potential estimates, particularly when arc elasticities (rather than substitution elasticities) are estimated.

Market size and vertical structure in the rail way industry

OpenAIRE

Matsushima, Noriaki; Mizutani, Fumitoshi

2011-01-01

We provide a theoretical framework to discuss the relation between market size and vertical structure in the railway industry. The framework is based on a simple downstream monopoly model with two input suppliers, labor forces and the rail infrastructure firm. The operation of the downstream firm (i.e., the train operating firm) generates costs on the rail infrastructure firm. We show that the downstream firm with a larger market size is more likely to integrate with the rail infrastructure f...

Effect size estimates: current use, calculations, and interpretation.

Science.gov (United States)

Fritz, Catherine O; Morris, Peter E; Richler, Jennifer J

2012-02-01

The Publication Manual of the American Psychological Association (American Psychological Association, 2001, American Psychological Association, 2010) calls for the reporting of effect sizes and their confidence intervals. Estimates of effect size are useful for determining the practical or theoretical importance of an effect, the relative contributions of factors, and the power of an analysis. We surveyed articles published in 2009 and 2010 in the Journal of Experimental Psychology: General, noting the statistical analyses reported and the associated reporting of effect size estimates. Effect sizes were reported for fewer than half of the analyses; no article reported a confidence interval for an effect size. The most often reported analysis was analysis of variance, and almost half of these reports were not accompanied by effect sizes. Partial η2 was the most commonly reported effect size estimate for analysis of variance. For t tests, 2/3 of the articles did not report an associated effect size estimate; Cohen's d was the most often reported. We provide a straightforward guide to understanding, selecting, calculating, and interpreting effect sizes for many types of data and to methods for calculating effect size confidence intervals and power analysis.

Stock Market Efficiency and Size of the Firm: Empirical Evidence from Pakistan

Directory of Open Access Journals (Sweden)

Ikram ul Haq

2014-03-01

Full Text Available The purpose of this paper is to examine the relationship between firm size and excess stock returns in Pakistani market. We construct a set of 10 portfolios based on size i.e., market capitalization, total assets and sales for the period between 2007 and 2011, and analyze the annual stock returns by using sorting and Fama & Macbeth model. The results of the study indicate a prominent size effect where smaller firm or size portfolios are found to have a greater average annual excess returns than bigger firm or size portfolios during the period under analysis. We find that small firms have significantly greater excess returns than larger firms. The study has strong implications for mutual funds managers, investment analysts as well as small investors who are continuously at a lookout for the trading strategies that beat the market.

Fuel Cells in Distributed Power Market Applications in the United States

International Nuclear Information System (INIS)

Rastler, D.

2002-01-01

This paper reviews results from EPRI market analysis, which examined the technical and economic market potential of fuel cells in distributed power markets in the United States. A methodology and approach for developing realistic quantitative estimates of market potential in competitive electricity markets is presented. Market size estimates for phosphoric acid, polymer exchange membrane, high temperature fuel cells (carbonate and solid oxide systems) and ultra-high efficient fuel cell hybrids are estimated. Market potentials are reviewed for fuel cells systems ranging in size from 3 kW up to 20-30 MW in scale and underlying assumptions are provided. The results and implications are discussed in relation to the changing U.S. electric utility market structures. Results will be of value to energy companies and to fuel cell developers seeking to understand revenue sales estimates, market size, and most profitable segments for fuel cells in the competitive US electric markets. (author)

Photometric estimation of defect size in radiation direction

International Nuclear Information System (INIS)

Zuev, V.M.

1993-01-01

Factors, affecting accuracy of photometric estimation of defect size in radiation transmission direction, are analyzed. Experimentally obtained dependences of contrast of defect image on its size in radiation transmission direction are presented. Practical recommendations on improving accuracy of photometric estimation of defect size in radiation transmission direction, are developed

Effect of repeat purchase and dynamic market size on diffusion of an innovative technological consumer product in a segmented market

DEFF Research Database (Denmark)

Aggarwal, S.; Gupta, A.; Govindan, K.

2014-01-01

creates a spectrum effect in market with an aim to create wider product awareness and influence the market size. Whereas the differentiated promotion strategy plays major role in external influence component in the respective segment and target for adoption by the current potential segment. Previous......This study develops diffusion models for technological consumer products under the marketing environment when a product is marketed in a segmented market and observes two distinctive promotional strategies of mass and differentiated promotion; an under explored study area. Mass promotion strategy...... studies on segmented diffusion models assumed only first time purchase and constant market size which may yield underestimated results and fail to give appropriate insight of the diffusion process. The study develops and validates generalized diffusion models for segmented market incorporating...

[Sample size calculation in clinical post-marketing evaluation of traditional Chinese medicine].

Science.gov (United States)

Fu, Yingkun; Xie, Yanming

2011-10-01

In recent years, as the Chinese government and people pay more attention on the post-marketing research of Chinese Medicine, part of traditional Chinese medicine breed has or is about to begin after the listing of post-marketing evaluation study. In the post-marketing evaluation design, sample size calculation plays a decisive role. It not only ensures the accuracy and reliability of post-marketing evaluation. but also assures that the intended trials will have a desired power for correctly detecting a clinically meaningful difference of different medicine under study if such a difference truly exists. Up to now, there is no systemic method of sample size calculation in view of the traditional Chinese medicine. In this paper, according to the basic method of sample size calculation and the characteristic of the traditional Chinese medicine clinical evaluation, the sample size calculation methods of the Chinese medicine efficacy and safety are discussed respectively. We hope the paper would be beneficial to medical researchers, and pharmaceutical scientists who are engaged in the areas of Chinese medicine research.

Sample Size Calculations for Population Size Estimation Studies Using Multiplier Methods With Respondent-Driven Sampling Surveys.

Science.gov (United States)

Fearon, Elizabeth; Chabata, Sungai T; Thompson, Jennifer A; Cowan, Frances M; Hargreaves, James R

2017-09-14

While guidance exists for obtaining population size estimates using multiplier methods with respondent-driven sampling surveys, we lack specific guidance for making sample size decisions. To guide the design of multiplier method population size estimation studies using respondent-driven sampling surveys to reduce the random error around the estimate obtained. The population size estimate is obtained by dividing the number of individuals receiving a service or the number of unique objects distributed (M) by the proportion of individuals in a representative survey who report receipt of the service or object (P). We have developed an approach to sample size calculation, interpreting methods to estimate the variance around estimates obtained using multiplier methods in conjunction with research into design effects and respondent-driven sampling. We describe an application to estimate the number of female sex workers in Harare, Zimbabwe. There is high variance in estimates. Random error around the size estimate reflects uncertainty from M and P, particularly when the estimate of P in the respondent-driven sampling survey is low. As expected, sample size requirements are higher when the design effect of the survey is assumed to be greater. We suggest a method for investigating the effects of sample size on the precision of a population size estimate obtained using multipler methods and respondent-driven sampling. Uncertainty in the size estimate is high, particularly when P is small, so balancing against other potential sources of bias, we advise researchers to consider longer service attendance reference periods and to distribute more unique objects, which is likely to result in a higher estimate of P in the respondent-driven sampling survey. ©Elizabeth Fearon, Sungai T Chabata, Jennifer A Thompson, Frances M Cowan, James R Hargreaves. Originally published in JMIR Public Health and Surveillance (http://publichealth.jmir.org), 14.09.2017.

Role of Relationship Marketing in Small and Medium-Sized Entreprises

Directory of Open Access Journals (Sweden)

Ružica Butigan

2011-06-01

Full Text Available Along with marketing, small and medium enterprises (SMEs are commonly associated in literature with relationship marketing which results in marketing networks. This paper examines the specific characteristics that differentiate large companies from small and medium-sized enterprises, and the reasons that prevent SMEs from engaging in traditional marketing within the scope of marketing mix. The paper also shows that the key characteristic which distinguishes small from large companies is a prominent role of owner/managers. The owner/manager affects marketing of SMEs by creating his or her own personal networks with stakeholders in the environment, and considers it an important strategic focus and a factor that increases the performance of marketing decision-making. After a thorough review of secondary data sources this paper examines relationship marketing as a marketing framework for SMEs and, finally, proves that relationship marketing is more appropriate for SMEs than are traditional marketing concepts, that relationship marketing and network marketing create an important framework for SMEs and that there is a link between relationship marketing, personal networks and SMEs.

On population size estimators in the Poisson mixture model.

Science.gov (United States)

Mao, Chang Xuan; Yang, Nan; Zhong, Jinhua

2013-09-01

Estimating population sizes via capture-recapture experiments has enormous applications. The Poisson mixture model can be adopted for those applications with a single list in which individuals appear one or more times. We compare several nonparametric estimators, including the Chao estimator, the Zelterman estimator, two jackknife estimators and the bootstrap estimator. The target parameter of the Chao estimator is a lower bound of the population size. Those of the other four estimators are not lower bounds, and they may produce lower confidence limits for the population size with poor coverage probabilities. A simulation study is reported and two examples are investigated. © 2013, The International Biometric Society.

Estimating correlation and covariance matrices by weighting of market similarity

OpenAIRE

Michael C. M\\"unnix; Rudi Sch\\"afer; Oliver Grothe

2010-01-01

We discuss a weighted estimation of correlation and covariance matrices from historical financial data. To this end, we introduce a weighting scheme that accounts for similarity of previous market conditions to the present one. The resulting estimators are less biased and show lower variance than either unweighted or exponentially weighted estimators. The weighting scheme is based on a similarity measure which compares the current correlation structure of the market to the structures at past ...

Estimating Phenomenological Parameters in Multi-Assets Markets

Science.gov (United States)

Raffaelli, Giacomo; Marsili, Matteo

Financial correlations exhibit a non-trivial dynamic behavior. This is reproduced by a simple phenomenological model of a multi-asset financial market, which takes into account the impact of portfolio investment on price dynamics. This captures the fact that correlations determine the optimal portfolio but are affected by investment based on it. Such a feedback on correlations gives rise to an instability when the volume of investment exceeds a critical value. Close to the critical point the model exhibits dynamical correlations very similar to those observed in real markets. We discuss how the model's parameter can be estimated in real market data with a maximum likelihood principle. This confirms the main conclusion that real markets operate close to a dynamically unstable point.

Even Giants Need A Club: Domestic Institutions, Market Size, And Regulatory Influence

OpenAIRE

DAVID BACH

2005-01-01

This paper show that work on international market regulation has paid insufficient attention to the critical role played by domestic political and regulatory institutions. Existing literature emphasizes the role of market power, determined by market size, in analyzing international regulatory influence. While we do not contest the importance of market power, we introduce the notion of domestic regulatory capacity to capture the domestic institutional side of international market regulation th...

Estimation of sample size and testing power (Part 4).

Science.gov (United States)

Hu, Liang-ping; Bao, Xiao-lei; Guan, Xue; Zhou, Shi-guo

2012-01-01

Sample size estimation is necessary for any experimental or survey research. An appropriate estimation of sample size based on known information and statistical knowledge is of great significance. This article introduces methods of sample size estimation of difference test for data with the design of one factor with two levels, including sample size estimation formulas and realization based on the formulas and the POWER procedure of SAS software for quantitative data and qualitative data with the design of one factor with two levels. In addition, this article presents examples for analysis, which will play a leading role for researchers to implement the repetition principle during the research design phase.

Technical Efficiency Evaluation of Market Age and Enterprise Size ...

African Journals Online (AJOL)

Technical Efficiency Evaluation of Market Age and Enterprise Size for Broiler Production in Imo State, Nigeria. ... Open Access DOWNLOAD FULL TEXT Subscription ... Key words: Broiler Production, Technical Efficiency and Scale of Operation ...

Utilizing Content Marketing in Small and Medium-Sized Organizations

OpenAIRE

Parviainen, Ville

2014-01-01

The major objective of this study is to find out how and to what extent online content is currently utilized for marketing purposes among small and medium-sized organizations in Finland. Additionally, positive and negative future prospects concerning this type of content marketing were explored. The study is mainly qualitative by nature. The empirical part of this thesis was carried out between July 2013 and March 2014 and it consists of five semi-structured interviews with five professio...

Estimating software development project size, using probabilistic ...

African Journals Online (AJOL)

Estimating software development project size, using probabilistic techniques. ... of managing the size of software development projects by Purchasers (Clients) and Vendors (Development ... EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

Comparing fishers' and scientific estimates of size at maturity and maximum body size as indicators for overfishing.

Science.gov (United States)

Mclean, Elizabeth L; Forrester, Graham E

2018-04-01

We tested whether fishers' local ecological knowledge (LEK) of two fish life-history parameters, size at maturity (SAM) at maximum body size (MS), was comparable to scientific estimates (SEK) of the same parameters, and whether LEK influenced fishers' perceptions of sustainability. Local ecological knowledge was documented for 82 fishers from a small-scale fishery in Samaná Bay, Dominican Republic, whereas SEK was compiled from the scientific literature. Size at maturity estimates derived from LEK and SEK overlapped for most of the 15 commonly harvested species (10 of 15). In contrast, fishers' maximum size estimates were usually lower than (eight species), or overlapped with (five species) scientific estimates. Fishers' size-based estimates of catch composition indicate greater potential for overfishing than estimates based on SEK. Fishers' estimates of size at capture relative to size at maturity suggest routine inclusion of juveniles in the catch (9 of 15 species), and fishers' estimates suggest that harvested fish are substantially smaller than maximum body size for most species (11 of 15 species). Scientific estimates also suggest that harvested fish are generally smaller than maximum body size (13 of 15), but suggest that the catch is dominated by adults for most species (9 of 15 species), and that juveniles are present in the catch for fewer species (6 of 15). Most Samaná fishers characterized the current state of their fishery as poor (73%) and as having changed for the worse over the past 20 yr (60%). Fishers stated that concern about overfishing, catching small fish, and catching immature fish contributed to these perceptions, indicating a possible influence of catch-size composition on their perceptions. Future work should test this link more explicitly because we found no evidence that the minority of fishers with more positive perceptions of their fishery reported systematically different estimates of catch-size composition than those with the more

Estimating spatio-temporal dynamics of size-structured populations

DEFF Research Database (Denmark)

Kristensen, Kasper; Thygesen, Uffe Høgsbro; Andersen, Ken Haste

2014-01-01

with simple stock dynamics, to estimate simultaneously how size distributions and spatial distributions develop in time. We demonstrate the method for a cod population sampled by trawl surveys. Particular attention is paid to correlation between size classes within each trawl haul due to clustering...... of individuals with similar size. The model estimates growth, mortality and reproduction, after which any aspect of size-structure, spatio-temporal population dynamics, as well as the sampling process can be probed. This is illustrated by two applications: 1) tracking the spatial movements of a single cohort...

How Rural Market Imperfections Shape the Relation Between Farm Size and Productivity

DEFF Research Database (Denmark)

Heltberg, Rasmus

The subject of this article is the alleged inverse relationship between farm size and productivity in developing countries. The recent controversy is reviewed, and a framework is provided to explain the inverse relationship based on plausible assumptions about imperfections in the markets for labor......, credit and land. On this basis testable hypotheses are derived. Using fram.level panel data from Pakistan, the framework is assessed by regressing output on operational fram size, size of owned holding, family size, tenurial status and irrigation status of the land. Household fixed effects are used...... to account for remaining unobserved heterogenity. It is concluded that an inverse relationship is present in Pakistan, and that the market imperfections framework performs well with the data...

Do Market Regulation and Financial Imperfections Affect Firm Size? New Empirical Evidence

OpenAIRE

Raquel Fonseca; Natalia Utrero González

2004-01-01

This paper investigates the importance that market regulation and financial imperfections have in firm size. We analyse institutions affecting labour market as Employment Protection Laws (EPL) and Product Market Regulation (PMR). Moreover, we study the effects of these institutions on firm growth. We use data from 29 industrial sectors across 15 developed countries. We find that market regulations related to financial imperfections help to explain differences in firm structure across countries.

Are the tobacco industry's claims about the size of the illicit cigarette market credible? The case of South Africa.

Science.gov (United States)

van Walbeek, Corné; Shai, Lerato

2015-06-01

The tobacco industry claims that illicit cigarette trade in South Africa is high and rising. This is often used as an argument not to increase the tobacco excise tax or to regulate tobacco products. To determine how the tobacco industry's estimates of the size of the illicit cigarette market have changed over time. Published media articles were obtained from South African Press Cuttings; published articles and press releases were sourced from the internet. The period of interest is 1990-2012. Between 1990 and 2012 we found 90 newspaper articles and press statements that emphasised the tobacco industry's view on illicit trade. Articles that reported on action taken against illicit trade were excluded. Between 2006 and early 2011 the Tobacco Institute of Southern Africa, a body representing the interests of large cigarette companies, reported that South Africa's illicit cigarette market share was 20%. This share increased to 25% in late 2011 and 30% in 2012. In a 2012 presentation by Tobacco Institute of Southern Africa to National Treasury the illicit market share in 2008 was indicated as 7.9%, compared with claims in that year that the illicit market share was 20%. Industry findings that the illicit market decreased in 2007 and 2008 were not reported in the press. The tobacco industry has adjusted previous estimates of the illicit trade share downwards to create the impression that illicit trade is high and rising. If previous estimates by the tobacco industry were incorrect the credibility of current estimates should be questioned. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Understanding the market for geographic information: A market segmentation and characteristics analysis

Science.gov (United States)

Piper, William S.; Mick, Mark W.

1994-01-01

Findings and results from a marketing research study are presented. The report identifies market segments and the product types to satisfy demand in each. An estimate of market size is based on the specific industries in each segment. A sample of ten industries was used in the study. The scientific study covered U.S. firms only.

Population estimates of extended family structure and size.

Science.gov (United States)

Garceau, Anne; Wideroff, Louise; McNeel, Timothy; Dunn, Marsha; Graubard, Barry I

2008-01-01

Population-based estimates of biological family size can be useful for planning genetic studies, assessing how distributions of relatives affect disease associations with family history and estimating prevalence of potential family support. Mean family size per person is estimated from a population-based telephone survey (n = 1,019). After multivariate adjustment for demographic variables, older and non-White respondents reported greater mean numbers of total, first- and second-degree relatives. Females reported more total and first-degree relatives, while less educated respondents reported more second-degree relatives. Demographic differences in family size have implications for genetic research. Therefore, periodic collection of family structure data in representative populations would be useful. Copyright 2008 S. Karger AG, Basel.

Market participation among rice producing households in Abia state ...

African Journals Online (AJOL)

Estimates of the determinants of market participation among households in the study area showed that the coefficients of household size, output, farm size, extension contact, distance from farm to market, membership of societies were significant in influencing market participation among rice producing households. Among ...

Retail Productivity: Investigating the Influence of Market Size and Regional Hierarchy

OpenAIRE

Öner, Özge

2014-01-01

This paper investigates the determinants of the productivity of independent retail stores in Sweden by focusing on the impact of market size and regional hierarchy while controlling for several store and employee characteristics over time. The analysis utilizes Swedish store-level data for the years 2002–2008. To capture the urban-periphery interaction in retail markets, the analysis (i) uses an accessible market potential measure, which captures the impact of the potential demand both in clo...

VOLTTRON™: Tech-to-Market Best-Practices Guide for Small- and Medium-Sized Commercial Buildings

Energy Technology Data Exchange (ETDEWEB)

Cort, Katherine A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Haack, Jereme N. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Katipamula, Srinivas [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Nicholls, Andrew K. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2016-07-11

VOLTTRON™ is an open-source distributed control and sensing platform developed by Pacific Northwest National Laboratory for the U.S. Department of Energy. It was developed to be used by the Office of Energy Efficiency and Renewable Energy to support transactive controls research and deployment activities. VOLTTRON is designed to be an overarching integration platform that could be used to bring together vendors, users, and developers and enable rapid application development and testing. The platform is designed to support modern control strategies, including the use of agent- and transaction-based controls. It also is designed to support the management of a wide range of applications, including heating, ventilation, and air-conditioning systems; electric vehicles; and distributed-energy and whole-building loads. This report was completed as part of the Building Technologies Office’s Technology-to-Market Initiative for VOLTTRON’s Market Validation and Business Case Development efforts. The report provides technology-to-market guidance and best practices related to VOLTTRON platform deployments and commercialization activities for use by entities serving small- and medium-sized commercial buildings. The report characterizes the platform ecosystem within the small- and medium-sized commercial building market and articulates the value proposition of VOLTTRON for three core participants in this ecosystem: 1) platform owners/adopters, 2) app developers, and 3) end-users. The report also identifies key market drivers and opportunities for open platform deployments in the small- and medium-sized commercial building market. Possible pathways to the market are described—laboratory testing to market adoption to commercialization. We also identify and address various technical and market barriers that could hinder deployment of VOLTTRON. Finally, we provide “best practice” tech-to-market guidance for building energy-related deployment efforts serving small- and

Assessing market competition and vendors' size and scope on AlphaBay.

Science.gov (United States)

Paquet-Clouston, Masarah; Décary-Hétu, David; Morselli, Carlo

2018-04-01

Since 2011, drug market participants have traded illegal drugs through cryptomarkets, a user-friendly infrastructure in which drug market participants can conduct business transactions. This study assesses market competition and the size and scope of drug vendors' activities on one of the largest cryptomarkets, AlphaBay, in order to better understand the challenges that drug vendors face when selling on this venue. Relying on data collected from AlphaBay, we calculate the degree of competition within the drug market using the Herfindhal-Hirshmann Index (HHI). We then follow a micro analytical approach and assess the size and scope of vendors' accounts. This is done by evaluating each vendor's market share over time using a group-based trajectory model (GBTM). Results from the GBTM are then used to assess vendors' exposure, diversity and experience based on their selling position in the market. The HHI scores demonstrate that cryptomarkets offer a highly competitive environment that fits in a top-heavy market structure. However, the distribution of vendors' market share trajectories shows that only a small portion of vendors (referred to as high-level vendors) succeed in generating regular sales, whereas the majority of vendors are relegated to being mere market spectators with almost zero sales. This inequality is exacerbated by the aggressive advertising of high-level vendors who post many listings. Overall, product diversity and experience is limited for all market participants regardless of their level of success. We interpret these results through Reuter's work on traditional illegal markets, e-commerce studies and the growing field of cryptomarket research. We conclude that, while offering a new venue for illegal drug transactions, in many ways, the economics of cryptomarkets for drug dealing are consistent with Reuter's classic assessment of illegal markets and the consequences of product illegality that underlie it. Cryptomarkets conflicting features, a

MARKET RISK ESTIMATION IN (T+-TRANSACTIONS

Directory of Open Access Journals (Sweden)

Radik B. Begov

2016-01-01

Full Text Available Market risk analysis and estimation are presentedin T+ transactionsas they are used within the Moscow Exchange. There is a need to do so as a result of the cut-off of a new REPO product with Central Counterpartner (CCP. Here repurchase agreement goes through the National Clearing Center (NCC, the last being a bank and a clearing structure within the Moscow Exchange group.NCC actsas an intermediary (so called “Central Counterpartner” between trading participants.REPOs with CCP raisecontractor claims and commitments to the CCP which takes the risk of default on commitments from unfair contract side. The REPO with CCP cut-off made ready a technological platform to implement T+2 trades at the Moscow Exchange. As a result of it there appeared the possibility to enter security purchase/sell contracts partially collateralized. All these transactions (the REPO with CCP, T+ made it a must determining security market risks. The paper is aimed at presenting VaR-like risk estimates. The methods used are from the computer fi nance. Unusual TS rate of return indicator is proposed and applied to find optimal portfolios under the Markowitz approach and their VaRs (losses forecasts given the real “big” share price data and various horizons. Portfolio extreme rate and loss forecasting is our goal. To this end the forecasts are computed for three horizons (2, 5 and 10 days and for three significance levels.There were developed R-, Excel- and Bloomberg-basedsoftware tools as needed. The whole range of proposed computing steps and the tables with charts may be considered as candidates to be included in the future market risk standards.Paper results permit capital market participants to choose the correct (as to the required risk level common stocks.

Association between inaccurate estimation of body size and obesity in schoolchildren

Directory of Open Access Journals (Sweden)

Larissa da Cunha Feio Costa

2015-12-01

Full Text Available Objectives: To investigate the prevalence of inaccurate estimation of own body size among Brazilian schoolchildren of both sexes aged 7-10 years, and to test whether overweight/obesity; excess body fat and central obesity are associated with inaccuracy. Methods: Accuracy of body size estimation was assessed using the Figure Rating Scale for Brazilian Children. Multinomial logistic regression was used to analyze associations. Results: The overall prevalence of inaccurate body size estimation was 76%, with 34% of the children underestimating their body size and 42% overestimating their body size. Obesity measured by body mass index was associated with underestimation of body size in both sexes, while central obesity was only associated with overestimation of body size among girls. Conclusions: The results of this study suggest there is a high prevalence of inaccurate body size estimation and that inaccurate estimation is associated with obesity. Accurate estimation of own body size is important among obese schoolchildren because it may be the first step towards adopting healthy lifestyle behaviors.

Size matters: Installed maximal unit size predicts market life cycles of electricity generation technologies and systems

International Nuclear Information System (INIS)

Li, N.

2008-01-01

The electricity generation technologies and systems are complex and change in very dynamic fashions, with a multitude of energy sources and prime movers. Since an important concept in generator design is the 'economies of scale', we discover that the installed maximal unit size (capacity) of the generators is a key 'envelope-pushing' characteristic with logistical behaviors. The logistical wavelet analysis of the max unit sizes for different fuels and prime movers, and the cumulative capacities, reveals universal quantitative features in the aggregate evolution of the power industry. We extract the transition times of the max sizes (spanning 10-90% of the saturation limits) for different technologies and systems, and discover that the max size saturation in the 90-99% range precedes the saturation of cumulative capacities of the corresponding systems in the US. While these universal laws are still empirical, they give us a simple yet elegant framework to examine the evolution of the power industry and markets in predictive, not just descriptive, terms. Such laws give us a quantitative tool to spot trends and predict future development, invaluable in planning and resource allocation based on intrinsic technology and system market life cycles

Estimating Price Elasticity using Market-Level Appliance Data

Energy Technology Data Exchange (ETDEWEB)

Fujita, K. Sydny [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2015-08-04

This report provides and update to and expansion upon our 2008 LBNL report “An Analysis of the Price Elasticity of Demand for Appliances,” in which we estimated an average relative price elasticity of -0.34 for major household appliances (Dale and Fujita 2008). Consumer responsiveness to price change is a key component of energy efficiency policy analysis; these policies influence consumer purchases through price both explicitly and implicitly. However, few studies address appliance demand elasticity in the U.S. market and public data sources are generally insufficient for rigorous estimation. Therefore, analysts have relied on a small set of outdated papers focused on limited appliance types, assuming long-term elasticities estimated for other durables (e.g., vehicles) decades ago are applicable to current and future appliance purchasing behavior. We aim to partially rectify this problem in the context of appliance efficiency standards by revisiting our previous analysis, utilizing data released over the last ten years and identifying additional estimates of durable goods price elasticities in the literature. Reviewing the literature, we find the following ranges of market-level price elasticities: -0.14 to -0.42 for appliances; -0.30 to -1.28 for automobiles; -0.47 to -2.55 for other durable goods. Brand price elasticities are substantially higher for these product groups, with most estimates -2.0 or more elastic. Using market-level shipments, sales value, and efficiency level data for 1989-2009, we run various iterations of a log-log regression model, arriving at a recommended range of short run appliance price elasticity between -0.4 and -0.5, with a default value of -0.45.

The genetics of overwintering performance in two-year old common carp and its relation to performance until market size.

Science.gov (United States)

Prchal, Martin; Kause, Antti; Vandeputte, Marc; Gela, David; Allamellou, Jean-Michel; Kumar, Girish; Bestin, Anastasia; Bugeon, Jérôme; Zhao, Jinfeng; Kocour, Martin

2018-01-01

Using farmed common carp, we investigated the genetic background of the second year overwintering performance and its relation to the performance during the third growing season and at market size. The experimental stock was established by partial factorial design with a series of 4 factorial matings of 5 dams and 10 sires each. The families were reared communally and pedigree was re-constructed with 93.6% success using 12 microsatellites on 2008 offspring. Three successive recordings (second autumn, third spring, and third autumn-market size) covering two periods (second overwintering, third growing season) were included. Body weight, Fulton's condition factor and percent muscle fat content were recorded at all times and headless carcass yield and fillet yield were recorded at market size. Specific growth rate, absolute and relative fat change and overall survival were calculated for each period. Heritability estimates were significantly different from zero and almost all traits were moderately to highly heritable (h2 = 0.36-1.00), except survival in both periods and fat change (both patterns) during overwintering (h2 = 0.12-0.15). Genetic and phenotypic correlations imply that selection against weight loss and fat loss during overwintering is expected to lead to a better winter survival, together with a positive effect on growth in the third growing season. Interestingly, higher muscle fat content was genetically correlated to lower survival in the following period (rg = -0.59; -0.53, respectively for winter and the third summer). On the other hand, higher muscle fat was also genetically linked to better slaughter yields. Moreover, selection for higher condition factor would lead to better performance during winter, growing season and at market size.

Estimation of sample size and testing power (part 5).

Science.gov (United States)

Hu, Liang-ping; Bao, Xiao-lei; Guan, Xue; Zhou, Shi-guo

2012-02-01

Estimation of sample size and testing power is an important component of research design. This article introduced methods for sample size and testing power estimation of difference test for quantitative and qualitative data with the single-group design, the paired design or the crossover design. To be specific, this article introduced formulas for sample size and testing power estimation of difference test for quantitative and qualitative data with the above three designs, the realization based on the formulas and the POWER procedure of SAS software and elaborated it with examples, which will benefit researchers for implementing the repetition principle.

Structural Estimation of Stock Market Participation Costs

DEFF Research Database (Denmark)

Khorunzhina, Natalia

2013-01-01

education programs can affect consumers' investment decisions. Using household data from the Panel Study of Income Dynamics, I estimate the magnitude of the participation cost, allowing for individual heterogeneity in it. The results show the average stock market participation cost is about 4–6% of labor...

The battery market

International Nuclear Information System (INIS)

Deshpande, S.L.

1991-01-01

The worldwide battery market is estimated to be $21 billion annually at present. The geographical distribution of this market is shown in this paper. The American (North and South), Western Europe and Africa, and Asian and Australia represent equal markets of $6 billion each. The communist block countries (including Russia and China) are estimated to represent a $3 billion market. Automotive and consumer batteries constitute more than 80% of the world battery market. Industrial batteries make up the rest. Secondary (rechargeable) batteries (automotive, for example) have only 60% share of the world battery consumption. Primary batteries (most toy batteries that are the throw away type) exceed rechargeables by far in units. However, the larger size of rechargeable batteries makes their total value larger despite the small number of units

Optimal Sizing of Energy Storage Systems for the Energy Procurement Problem in Multi-Period Markets under Uncertainties

Directory of Open Access Journals (Sweden)

Ryusuke Konishi

2018-01-01

Full Text Available In deregulated electricity markets, minimizing the procurement costs of electricity is a critical problem for procurement agencies (PAs. However, uncertainty is inevitable for PAs and includes multiple factors such as market prices, photovoltaic system (PV output and demand. This study focuses on settlements in multi-period markets (a day-ahead market and a real-time market and the installation of energy storage systems (ESSs. ESSs can be utilized for time arbitrage in the day-ahead market and to reduce the purchasing/selling of electricity in the real-time market. However, the high costs of an ESS mean the size of the system needs to be minimized. In addition, when determining the size of an ESS, it is important to identify the size appropriate for each role. Therefore, we employ the concept of a “slow” and a “fast” ESS to quantify the size of a system’s role, based on the values associated with the various uncertainties. Because the problem includes nonlinearity and non-convexity, we solve it within a realistic computational burden by reformulating the problem using reasonable assumptions. Therefore, this study identifies the optimal sizes of ESSs and procurement, taking into account the uncertainties of prices in multi-period markets, PV output and demand.

Beyond Crowd Judgments: Data-driven Estimation of Market Value in Association Football

DEFF Research Database (Denmark)

Müller, Oliver; Simons, Alexander; Weinmann, Markus

2017-01-01

concern. Market values can be understood as estimates of transfer fees—that is, prices that could be paid for a player on the football market—so they play an important role in transfer negotiations. These values have traditionally been estimated by football experts, but crowdsourcing has emerged......Association football is a popular sport, but it is also a big business. From a managerial perspective, the most important decisions that team managers make concern player transfers, so issues related to player valuation, especially the determination of transfer fees and market values, are of major......’ market values using multilevel regression analysis. The regression results suggest that data-driven estimates of market value can overcome several of the crowd's practical limitations while producing comparably accurate numbers. Our results have important implications for football managers and scouts...

CATCH ESTIMATION AND SIZE DISTRIBUTION OF BILLFISHES LANDED IN PORT OF BENOA, BALI

Directory of Open Access Journals (Sweden)

Bram Setyadji

2012-06-01

Full Text Available Billfishes are generally considered as by-product in tuna long line fisheries that have high economic value in the market. By far, the information about Indian Ocean billfish biology and fisheries especially in Indonesia is very limited. This research aimed to elucidate the estimation of production and size distribution of billfishes landed in port of Benoa during 2010 (February – December through daily observation at the processing plants. The result showed that the landings dominated by Swordfish (Xiphias gladius 54.9%, Blue marlin (Makaira mazara 17.8% and Black marlin (Makaira indica 13.0% respectively, followed by small amount of striped marlin (Tetrapturus audax, sailfish (Istiophorus platypterus, and shortbil spearfish (Tetrapturus Angustirostris. Generally the individual size of billfishes range between 68 and 206 cm (PFL, and showing negative allometric pattern except on swordfish that was isometric. Most of the billfish landed haven’t reached their first sexual maturity.

The potential global market size and public health value of an HIV-1 vaccine in a complex global market.

Science.gov (United States)

Marzetta, Carol A; Lee, Stephen S; Wrobel, Sandra J; Singh, Kanwarjit J; Russell, Nina; Esparza, José

2010-07-05

An effective HIV vaccine will be essential for the control of the HIV pandemic. This study evaluated the potential global market size and value of a hypothetical HIV vaccine and considered clade diversity, disease burden, partial prevention of acquisition, impact of a reduction in viral load resulting in a decrease in transmission and delay to treatment, health care system differences regarding access, and HIV screening and vaccination, across all public and private markets. Vaccine product profiles varied from a vaccine that would have no effect on preventing infection to a vaccine that would effectively prevent infection and reduce viral load. High disease burden countries (HDBC; HIV prevalence > or = 1%) were assumed to routinely vaccinate pre-sexually active adolescents (10 years old), whereas low disease burden countries (LDBC; HIV prevalence rate market value of $210 million to $2.7 billion, depending on the vaccine product profile. If one-time catch-up campaigns were included (11-14 years old for HDBC and higher risk groups for LDBC), the additional cumulative approximately 70-237 million doses were needed over a 10-year period with a potential market value of approximately $695 million to $13.4 billion, depending on the vaccine product profile. Market size and value varied across market segments with the majority of the value in high income countries and the majority of the demand in low income countries. However, the value of the potential market in low income countries is still significant with up to $550 million annually for routine vaccination only and up to $1.7 billion for a one-time only catch-up campaign in 11-14 years old. In the most detail to date, this study evaluated market size and value of a potential multi-clade HIV vaccine, accounting for differences in disease burden, product profile and health care complexities. These findings provide donors and suppliers highly credible new data to consider in their continued efforts to develop an HIV-1

Updated Estimates of the Remaining Market Potential of the U.S. ESCO Industry

Energy Technology Data Exchange (ETDEWEB)

Larsen, Peter H. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Analysis and Environmental Impacts Div.; Carvallo Bodelon, Juan Pablo [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Analysis and Environmental Impacts Div.; Goldman, Charles A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Analysis and Environmental Impacts Div.; Murphy, Sean [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Analysis and Environmental Impacts Div.; Stuart, Elizabeth [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Analysis and Environmental Impacts Div.

2017-04-01

The energy service company (ESCO) industry has a well-established track record of delivering energy and economic savings in the public and institutional buildings sector, primarily through the use of performance-based contracts. The ESCO industry often provides (or helps arrange) private sector financing to complete public infrastructure projects with little or no up-front cost to taxpayers. In 2014, total U.S. ESCO industry revenue was estimated at $5.3 billion. ESCOs expect total industry revenue to grow to $7.6 billion in 2017—a 13% annual growth rate from 2015-2017. Researchers at Lawrence Berkeley National Laboratory (LBNL) were asked by the U.S. Department of Energy Federal Energy Management Program (FEMP) to update and expand our estimates of the remaining market potential of the U.S. ESCO industry. We define remaining market potential as the aggregate amount of project investment by ESCOs that is technically possible based on the types of projects that ESCOS have historically implemented in the institutional, commercial, and industrial sectors using ESCO estimates of current market penetration in those sectors. In this analysis, we report U.S. ESCO industry remaining market potential under two scenarios: (1) a base case and (2) a case “unfettered” by market, bureaucratic, and regulatory barriers. We find that there is significant remaining market potential for the U.S. ESCO industry under both the base and unfettered cases. For the base case, we estimate a remaining market potential of $92-$201 billion ($2016). We estimate a remaining market potential of $190-$333 billion for the unfettered case. It is important to note, however, that there is considerable uncertainty surrounding the estimates for both the base and unfettered cases.

THE RELATIONSHIP MARKETING APPLICATION IN SMALL AND MEDIUM-SIZED ENTERPRISES

Directory of Open Access Journals (Sweden)

SABOU FELICIA

2016-12-01

Full Text Available The paper presents the importance of relationship marketing, the communication between customers and romanian small and medium-sized enterprises, analyzing also how are investigated and resolved the complaints received from the customers. In the paper, I made a study through I analyzed if the small and medium-sized enterprises undertake investigations about the reasons which they have lost customers. The study was conducted during january - february 2016, the main research methods used in the study were observation, documentation, analysis and market survey. Also, I chose the study questionnaire as research tool. From this study resulted that 79,31% of companies surveyed, were concerned and investigated the reasons they lost customers. Customer satisfaction is very important to business success, so it is recommended that companies must pay attention to the customers reactions and customers dissatisfaction consequences.

A Social Media Marketing Plan for a Medium-sized Consumer Goods Company

OpenAIRE

Okolie, Emeka

2013-01-01

The objective of this study is to develop a social media marketing plan for the case com-pany to integrate it into its existing marketing communications. The case company of this study is a medium-sized consumer goods producing company that advertises its brand and products using traditional methods of advertising (radio, television, flyers and event promotion). At the moment, these methods seem to be lacking in efficiency and effective-ness caused by the saturation of marketing information w...

How to Estimate and Interpret Various Effect Sizes

Science.gov (United States)

Vacha-Haase, Tammi; Thompson, Bruce

2004-01-01

The present article presents a tutorial on how to estimate and interpret various effect sizes. The 5th edition of the Publication Manual of the American Psychological Association (2001) described the failure to report effect sizes as a "defect" (p. 5), and 23 journals have published author guidelines requiring effect size reporting. Although…

Parabolic Free Boundary Price Formation Models Under Market Size Fluctuations

KAUST Repository

Markowich, Peter A.; Teichmann, Josef; Wolfram, Marie Therese

2016-01-01

In this paper we propose an extension of the Lasry-Lions price formation model which includes uctuations of the numbers of buyers and vendors. We analyze the model in the case of deterministic and stochastic market size uctuations and present

Food photographs in portion size estimation among adolescent Mozambican girls.

Science.gov (United States)

Korkalo, Liisa; Erkkola, Maijaliisa; Fidalgo, Lourdes; Nevalainen, Jaakko; Mutanen, Marja

2013-09-01

To assess the validity of food photographs in portion size estimation among adolescent girls in Mozambique. The study was carried out in preparation for the larger ZANE study, which used the 24 h dietary recall method. Life-sized photographs of three portion sizes of two staple foods and three sauces were produced. Participants ate weighed portions of one staple food and one sauce. After the meal, they were asked to estimate the amount of food with the aid of the food photographs. Zambezia Province, Mozambique. Ninety-nine girls aged 13–18 years. The mean differences between estimated and actual portion sizes relative to the actual portion size ranged from 219% to 8% for different foods. The respective mean difference for all foods combined was 25% (95% CI 212, 2 %). Especially larger portions of the staple foods were often underestimated. For the staple foods, between 62% and 64% of the participants were classified into the same thirds of the distribution of estimated and actual food consumption and for sauces, the percentages ranged from 38% to 63%. Bland–Altman plots showed wide limits of agreement. Using life-sized food photographs among adolescent Mozambican girls resulted in a rather large variation in the accuracy of individuals’ estimates. The ability to rank individuals according to their consumption was, however, satisfactory for most foods. There seems to be a need to further develop and test food photographs used in different populations in Sub-Saharan Africa to improve the accuracy of portion size estimates.

Operation and sizing of energy storage for wind power plants in a market system

International Nuclear Information System (INIS)

Korpaas, M.; Holen, A.T.

2003-01-01

This paper presents a method for the scheduling and operation of energy storage for wind power plants in electricity markets. A dynamic programming algorithm is employed to determine the optimal energy exchange with the market for a specified scheduling period, taking into account transmission constraints. During operation, the energy storage is used to smooth variations in wind power production in order to follow the scheduling plan. The method is suitable for any type of energy storage and is also useful for other intermittent energy resources than wind. An application of the method to a case study is also presented, where the impact of energy storage sizing and wind forecasting accuracy on system operation and economics are emphasized. Simulation results show that energy storage makes it possible for owners of wind power plants to take advantage of variations in the spot price, by thus increasing the value of wind power in electricity markets. With present price estimates, energy storage devices such as reversible fuel cells are likely to be a more expensive alternative than grid expansions for the siting of wind farms in weak networks. However, for areas where grid expansions lead to unwanted interference with the local environment, energy storage should be considered as a reasonable way to increase the penetration of wind power. (author)

Market Brief. Status of the Voluntary Renewable Energy Certificate Market (2011 Data)

Energy Technology Data Exchange (ETDEWEB)

Heeter, Jenny [National Renewable Energy Lab. (NREL), Golden, CO (United States); Armstrong, Philip [National Renewable Energy Lab. (NREL), Golden, CO (United States); Bird, Lori [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2012-09-01

This report documents the status and trends of U.S. 'voluntary' markets -- those in which consumers and institutions purchase renewable energy to match their electricity needs on a voluntary basis. Voluntary REC markets continue to exhibit growth and spur renewable energy development. Voluntary green power markets provide an additional revenue stream for renewable energy projects and raise consumer awareness of the benefits of renewable energy. Although a full estimate of the size of the voluntary market is not available for 2011, this review uses indicative metrics to capture 2011 voluntary market trends.

Market Brief: Status of the Voluntary Renewable Energy Certificate Market (2011 Data)

Energy Technology Data Exchange (ETDEWEB)

Heeter, J.; Armstrong, P.; Bird, L.

2012-09-01

This report documents the status and trends of U.S. 'voluntary' markets -- those in which consumers and institutions purchase renewable energy to match their electricity needs on a voluntary basis. Voluntary REC markets continue to exhibit growth and spur renewable energy development. Voluntary green power markets provide an additional revenue stream for renewable energy projects and raise consumer awareness of the benefits of renewable energy. Although a full estimate of the size of the voluntary market is not available for 2011, this review uses indicative metrics to capture 2011 voluntary market trends.

Estimating post-marketing exposure to pharmaceutical products using ex-factory distribution data.

Science.gov (United States)

Telfair, Tamara; Mohan, Aparna K; Shahani, Shalini; Klincewicz, Stephen; Atsma, Willem Jan; Thomas, Adrian; Fife, Daniel

2006-10-01

The pharmaceutical industry has an obligation to identify adverse reactions to drug products during all phases of drug development, including the post-marketing period. Estimates of population exposure to pharmaceutical products are important to the post-marketing surveillance of drugs, and provide a context for assessing the various risks and benefits, including drug safety, associated with drug treatment. This paper describes a systematic approach to estimating post-marketing drug exposure using ex-factory shipment data to estimate the quantity of medication available, and dosage information (stratified by indication or other factors as appropriate) to convert the quantity of medication to person time of exposure. Unlike the non-standardized methods often used to estimate exposure, this approach provides estimates whose calculations are explicit, documented, and consistent across products and over time. The methods can readily be carried out by an individual or small group specializing in this function, and lend themselves to automation. The present estimation approach is practical and relatively uncomplicated to implement. We believe it is a useful innovation. Copyright 2006 John Wiley & Sons, Ltd.

Korean Online Game's Platform Competition under Two-Sided Market Characteristic

OpenAIRE

SeonJun Kang; Sang-Yong Tom Lee

2014-01-01

While the growth of total game market size slowed down and the arcade game industry started to shrink, the online game market keeps increasing, attaining 26.5% annual growth rate for the early 2010's. Korea's online game business is especially popular, so that the size is about US$ 4 billion, which is 64.2% of Korea's total game industry. In 2013, Game market size and online game market size were estimated to be about US$ 9 billion and US$ 7 billion, respectively. From a standpoint of sales, ...

Sample size for post-marketing safety studies based on historical controls.

Science.gov (United States)

Wu, Yu-te; Makuch, Robert W

2010-08-01

As part of a drug's entire life cycle, post-marketing studies are an important part in the identification of rare, serious adverse events. Recently, the US Food and Drug Administration (FDA) has begun to implement new post-marketing safety mandates as a consequence of increased emphasis on safety. The purpose of this research is to provide exact sample size formula for the proposed hybrid design, based on a two-group cohort study with incorporation of historical external data. Exact sample size formula based on the Poisson distribution is developed, because the detection of rare events is our outcome of interest. Performance of exact method is compared to its approximate large-sample theory counterpart. The proposed hybrid design requires a smaller sample size compared to the standard, two-group prospective study design. In addition, the exact method reduces the number of subjects required in the treatment group by up to 30% compared to the approximate method for the study scenarios examined. The proposed hybrid design satisfies the advantages and rationale of the two-group design with smaller sample sizes generally required. 2010 John Wiley & Sons, Ltd.

INTERNATIONALIZATION PLANNING : The German market analysis for Alkuvoima East Ltd.

OpenAIRE

Klimchuk, Sviatoslav

2013-01-01

The study is focused on estimating the potential of the digital marketing market in Germany, and formulating the recommendations for the small-sized Bulgarian-Finnish digital marketing agency Alkuvioma East Ltd. in respect of the company’s potential entry in the German market. The primary aim of the research is a comprehensive analysis of the market that covers the study of the market size, demand, competitors and customers. The company itself is also subjected to the analysis with partic...

“One-size-fits-all”? Differentiation in destinations’ marketing goals and strategies to achieve them

OpenAIRE

Avraham, Eli; Ketter, Eran

2015-01-01

While tourism marketing literature tends to present marketing as a ‘one-size-fits-all’ process, the current study suggests various destination marketing goals. Until today, the literature mainly concentrated on analyzing marketing strategies, tactics, tools and initiatives for enhancing and perceiving tourism, while other marketing goals were neglected, such as marketing unfamiliar destinations or promoting tourism during and after tourism crises. The purpose of this study is to propose the m...

Estimating Non-Market Impacts of Climate Change and Climate Policy

International Nuclear Information System (INIS)

Rothman, D.S.; Amelung, B.; Polome, P.

2003-01-01

A number of studies over the past few decades have attempted to estimate the potential impacts of climate change and climate policy. For reasons related to, inter alia, our incomplete understanding of the workings of many natural and social systems, the tremendous spatial and temporal variability in these systems, and the long time frames over which the issue of climate change will play out, there are large degrees of uncertainty in these estimates. Some of the most rancorous debates, however, have focused on those studies that have attempted to place economic values on these impacts. This should not be surprising as the outcomes of these studies have played an important role in the debates over climate policy. Rightly or wrongly, the estimates presented in these studies are often held up against similar estimates of the costs of mitigating against climate change. The process of economic valuation of environmental and social issues is still relatively young, much less its application to the potential impacts of climate change and climate policy. Issues such as climate change push existing techniques to their limits, and possibly beyond. Among the topics that have raised the most concern are the choice of the proper baseline against which to make comparisons, the treatment of uncertainty in human and natural systems, incomplete accounting, the actual valuation of specific impacts, and the aggregation of impacts over time and across widely differing societies. Some of the more recent studies have tried to address these issues, albeit not always satisfactorily. One aspect that makes the economic valuation of environmental and social issues difficult is that it requires addressing impacts that are not typically associated with economic markets, so called nonmarket impacts. In addition to not being traded in markets, many of these impacts affect goods and services that have the characteristic of being public goods, i.e. it is not possible to restrict their use to a

Impaired hand size estimation in CRPS.

Science.gov (United States)

Peltz, Elena; Seifert, Frank; Lanz, Stefan; Müller, Rüdiger; Maihöfner, Christian

2011-10-01

A triad of clinical symptoms, ie, autonomic, motor and sensory dysfunctions, characterizes complex regional pain syndromes (CRPS). Sensory dysfunction comprises sensory loss or spontaneous and stimulus-evoked pain. Furthermore, a disturbance in the body schema may occur. In the present study, patients with CRPS of the upper extremity and healthy controls estimated their hand sizes on the basis of expanded or compressed schematic drawings of hands. In patients with CRPS we found an impairment in accurate hand size estimation; patients estimated their own CRPS-affected hand to be larger than it actually was when measured objectively. Moreover, overestimation correlated significantly with disease duration, neglect score, and increase of two-point-discrimination-thresholds (TPDT) compared to the unaffected hand and to control subjects' estimations. In line with previous functional imaging studies in CRPS patients demonstrating changes in central somatotopic maps, we suggest an involvement of the central nervous system in this disruption of the body schema. Potential cortical areas may be the primary somatosensory and posterior parietal cortices, which have been proposed to play a critical role in integrating visuospatial information. CRPS patients perceive their affected hand to be bigger than it is. The magnitude of this overestimation correlates with disease duration, decreased tactile thresholds, and neglect-score. Suggesting a disrupted body schema as the source of this impairment, our findings corroborate the current assumption of a CNS involvement in CRPS. Copyright © 2011 American Pain Society. Published by Elsevier Inc. All rights reserved.

Measuring the effectiveness of marketing activities use in relation to company size

Directory of Open Access Journals (Sweden)

Lucie Sychrová

2013-01-01

Full Text Available The aim of this paper is to research the relationship between measurements of effectiveness of marketing activities and company size. An analysis of the economic sources, professional publications, analysis and reports of previous research shows that the concept of measuring of effectiveness is one of the key themes, which economists always pay much attention. It is a criterion that helps to rationally decide on the use limited resources to meet the needs that are not limited. This topic deals with numerous domestic and foreign literatures. The authors are not only different concepts of effectiveness, but also the using terminology. There are multiple definitions of terms “effectiveness” For the same purpose and meaning. The same concept is often defined semantically different. Therefore, every company has a strong interest to be in all their activities more effectively than the competition. Logical response to changes and requirements of nowadays is using a combination of lot of methods to measure marketing effectiveness. Methods used for this article includes two phases. The first it was gained date by primary research, using a structure questionnaire and processed by statistical software SPSS. Research sample consists 115 companies operating in the Czech environment, which was chosen at random. There is investigated the correlation between measuring the effectiveness of marketing activities and company size. The second part investigated the dependence between the choice of metrics used to measure the effectiveness and company size. The results of the research showed that there is no correlation between measuring the effectiveness of marketing activities and company size. The value of Pearson Chi-Square test is greater than 0.05, it is 0.187. We can presume that dependency does not exist or it is small for these. Value of Symmetric measures is 0.432, which means that the intensity tends to be small rather than high.

Body size estimation of self and others in females varying in BMI.

Directory of Open Access Journals (Sweden)

Anne Thaler

Full Text Available Previous literature suggests that a disturbed ability to accurately identify own body size may contribute to overweight. Here, we investigated the influence of personal body size, indexed by body mass index (BMI, on body size estimation in a non-clinical population of females varying in BMI. We attempted to disentangle general biases in body size estimates and attitudinal influences by manipulating whether participants believed the body stimuli (personalized avatars with realistic weight variations represented their own body or that of another person. Our results show that the accuracy of own body size estimation is predicted by personal BMI, such that participants with lower BMI underestimated their body size and participants with higher BMI overestimated their body size. Further, participants with higher BMI were less likely to notice the same percentage of weight gain than participants with lower BMI. Importantly, these results were only apparent when participants were judging a virtual body that was their own identity (Experiment 1, but not when they estimated the size of a body with another identity and the same underlying body shape (Experiment 2a. The different influences of BMI on accuracy of body size estimation and sensitivity to weight change for self and other identity suggests that effects of BMI on visual body size estimation are self-specific and not generalizable to other bodies.

Body size estimation of self and others in females varying in BMI.

Science.gov (United States)

Thaler, Anne; Geuss, Michael N; Mölbert, Simone C; Giel, Katrin E; Streuber, Stephan; Romero, Javier; Black, Michael J; Mohler, Betty J

2018-01-01

Previous literature suggests that a disturbed ability to accurately identify own body size may contribute to overweight. Here, we investigated the influence of personal body size, indexed by body mass index (BMI), on body size estimation in a non-clinical population of females varying in BMI. We attempted to disentangle general biases in body size estimates and attitudinal influences by manipulating whether participants believed the body stimuli (personalized avatars with realistic weight variations) represented their own body or that of another person. Our results show that the accuracy of own body size estimation is predicted by personal BMI, such that participants with lower BMI underestimated their body size and participants with higher BMI overestimated their body size. Further, participants with higher BMI were less likely to notice the same percentage of weight gain than participants with lower BMI. Importantly, these results were only apparent when participants were judging a virtual body that was their own identity (Experiment 1), but not when they estimated the size of a body with another identity and the same underlying body shape (Experiment 2a). The different influences of BMI on accuracy of body size estimation and sensitivity to weight change for self and other identity suggests that effects of BMI on visual body size estimation are self-specific and not generalizable to other bodies.

Estimating particle number size distributions from multi-instrument observations with Kalman Filtering

Energy Technology Data Exchange (ETDEWEB)

Viskari, T.

2012-07-01

Atmospheric aerosol particles have several important effects on the environment and human society. The exact impact of aerosol particles is largely determined by their particle size distributions. However, no single instrument is able to measure the whole range of the particle size distribution. Estimating a particle size distribution from multiple simultaneous measurements remains a challenge in aerosol physical research. Current methods to combine different measurements require assumptions concerning the overlapping measurement ranges and have difficulties in accounting for measurement uncertainties. In this thesis, Extended Kalman Filter (EKF) is presented as a promising method to estimate particle number size distributions from multiple simultaneous measurements. The particle number size distribution estimated by EKF includes information from prior particle number size distributions as propagated by a dynamical model and is based on the reliabilities of the applied information sources. Known physical processes and dynamically evolving error covariances constrain the estimate both over time and particle size. The method was tested with measurements from Differential Mobility Particle Sizer (DMPS), Aerodynamic Particle Sizer (APS) and nephelometer. The particle number concentration was chosen as the state of interest. The initial EKF implementation presented here includes simplifications, yet the results are positive and the estimate successfully incorporated information from the chosen instruments. For particle sizes smaller than 4 micrometers, the estimate fits the available measurements and smooths the particle number size distribution over both time and particle diameter. The estimate has difficulties with particles larger than 4 micrometers due to issues with both measurements and the dynamical model in that particle size range. The EKF implementation appears to reduce the impact of measurement noise on the estimate, but has a delayed reaction to sudden

Improving accuracy of portion-size estimations through a stimulus equivalence paradigm.

Science.gov (United States)

Hausman, Nicole L; Borrero, John C; Fisher, Alyssa; Kahng, SungWoo

2014-01-01

The prevalence of obesity continues to increase in the United States (Gordon-Larsen, The, & Adair, 2010). Obesity can be attributed, in part, to overconsumption of energy-dense foods. Given that overeating plays a role in the development of obesity, interventions that teach individuals to identify and consume appropriate portion sizes are warranted. Specifically, interventions that teach individuals to estimate portion sizes correctly without the use of aids may be critical to the success of nutrition education programs. The current study evaluated the use of a stimulus equivalence paradigm to teach 9 undergraduate students to estimate portion size accurately. Results suggested that the stimulus equivalence paradigm was effective in teaching participants to make accurate portion size estimations without aids, and improved accuracy was observed in maintenance sessions that were conducted 1 week after training. Furthermore, 5 of 7 participants estimated the target portion size of novel foods during extension sessions. These data extend existing research on teaching accurate portion-size estimations and may be applicable to populations who seek treatment (e.g., overweight or obese children and adults) to teach healthier eating habits. © Society for the Experimental Analysis of Behavior.

Size of the direct-to-consumer genomic testing market.

Science.gov (United States)

Wright, Caroline F; Gregory-Jones, Shelley

2010-09-01

There has been enormous interest in the recent development of consumer genomics services, but very little is known about their impact. Using publicly available information, we estimate that the market for genetic susceptibility tests for complex diseases is much smaller than previously suggested, and hence consider that regulation through restrictive statutory legislation may be excessive.

Estimating the commodity market price of risk for energy prices

International Nuclear Information System (INIS)

Kolos, Sergey P.; Ronn, Ehud I.

2008-01-01

The purpose of this paper is to estimate the ''market price of risk'' (MPR) for energy commodities, the ratio of expected return to standard deviation. The MPR sign determines whether energy forward prices are upward- or downward-biased predictors of expected spot prices. We estimate MPRs using spot and futures prices, while accounting for the Samuelson effect. We find long-term MPRs generally positive and short-term negative, consistent with positive energy betas and hedging, respectively. In spot electricity markets, MPRs in Day-Ahead Prices agree with short-dated futures. Our results relate risk premia to informed hedging decisions, and futures prices to forecast/expected prices. (author)

Genome size estimation: a new methodology

Science.gov (United States)

Álvarez-Borrego, Josué; Gallardo-Escárate, Crisitian; Kober, Vitaly; López-Bonilla, Oscar

2007-03-01

Recently, within the cytogenetic analysis, the evolutionary relations implied in the content of nuclear DNA in plants and animals have received a great attention. The first detailed measurements of the nuclear DNA content were made in the early 40's, several years before Watson and Crick proposed the molecular structure of the DNA. In the following years Hewson Swift developed the concept of "C-value" in reference to the haploid phase of DNA in plants. Later Mirsky and Ris carried out the first systematic study of genomic size in animals, including representatives of the five super classes of vertebrates as well as of some invertebrates. From these preliminary results it became evident that the DNA content varies enormously between the species and that this variation does not bear relation to the intuitive notion from the complexity of the organism. Later, this observation was reaffirmed in the following years as the studies increased on genomic size, thus denominating to this characteristic of the organisms like the "Paradox of the C-value". Few years later along with the no-codification discovery of DNA the paradox was solved, nevertheless, numerous questions remain until nowadays unfinished, taking to denominate this type of studies like the "C-value enigma". In this study, we reported a new method for genome size estimation by quantification of fluorescence fading. We measured the fluorescence intensity each 1600 milliseconds in DAPI-stained nuclei. The estimation of the area under the graph (integral fading) during fading period was related with the genome size.

Capital market financing, firm growth, and firm size distribution

OpenAIRE

Didier Brandao,Tatiana; Levine,Ross Eric; Schmukler,Sergio L.

2015-01-01

How many and which firms issue equity and bonds in domestic and international markets, how do these firms grow relative to non-issuing firms, and how does firm performance vary along the firm size distribution? To evaluate these questions, a new data set is constructed by matching data on firm-level capital raising activity with balance sheet data for 45,527 listed firms in 51 countries. T...

Estimating Sample Size for Usability Testing

Directory of Open Access Journals (Sweden)

Alex Cazañas

2017-02-01

Full Text Available One strategy used to assure that an interface meets user requirements is to conduct usability testing. When conducting such testing one of the unknowns is sample size. Since extensive testing is costly, minimizing the number of participants can contribute greatly to successful resource management of a project. Even though a significant number of models have been proposed to estimate sample size in usability testing, there is still not consensus on the optimal size. Several studies claim that 3 to 5 users suffice to uncover 80% of problems in a software interface. However, many other studies challenge this assertion. This study analyzed data collected from the user testing of a web application to verify the rule of thumb, commonly known as the “magic number 5”. The outcomes of the analysis showed that the 5-user rule significantly underestimates the required sample size to achieve reasonable levels of problem detection.

Estimation of particle size distribution of nanoparticles from electrical ...

Indian Academy of Sciences (India)

2018-02-02

Feb 2, 2018 ... An indirect method of estimation of size distribution of nanoparticles in a nanocomposite is ... The present approach exploits DC electrical current–voltage ... the sizes of nanoparticles (NPs) by electrical characterization.

Relationship marketing of small to medium sized textile retailers in the Northwest Province / Fred Angels Amulike Musika

OpenAIRE

Musika, Fred Angels Amulike

2002-01-01

This study concentrated on the concept of relationship marketing and its implementation by small and medium sized textile retailers in the Northwest province of South Africa. This study addressed the gap between the relationship marketing theory and its implementation by small and medium sized textile retailers in the textile industry of the Northwest province. Researchers in relationship marketing have started to realise that there is a definite need for detailed empirical ...

Advance market commitments for vaccines against neglected diseases: estimating costs and effectiveness.

Science.gov (United States)

Berndt, Ernst R; Glennerster, Rachel; Kremer, Michael R; Lee, Jean; Levine, Ruth; Weizsäcker, Georg; Williams, Heidi

2007-05-01

The G8 is considering committing to purchase vaccines against diseases concentrated in low-income countries (if and when desirable vaccines are developed) as a way to spur research and development on vaccines for these diseases. Under such an 'advance market commitment,' one or more sponsors would commit to a minimum price to be paid per person immunized for an eligible product, up to a certain number of individuals immunized. For additional purchases, the price would eventually drop to close to marginal cost. If no suitable product were developed, no payments would be made. We estimate the offer size which would make revenues similar to the revenues realized from investments in typical existing commercial pharmaceutical products, as well as the degree to which various model contracts and assumptions would affect the cost-effectiveness of such a commitment. We make adjustments for lower marketing costs under an advance market commitment and the risk that a developer may have to share the market with subsequent developers. We also show how this second risk could be reduced, and money saved, by introducing a superiority clause to a commitment. Under conservative assumptions, we document that a commitment comparable in value to sales earned by the average of a sample of recently launched commercial products (adjusted for lower marketing costs) would be a highly cost-effective way to address HIV/AIDS, malaria, and tuberculosis. Sensitivity analyses suggest most characteristics of a hypothetical vaccine would have little effect on the cost-effectiveness, but that the duration of protection conferred by a vaccine strongly affects potential cost-effectiveness. Readers can conduct their own sensitivity analyses employing a web-based spreadsheet tool. Copyright (c) 2006 John Wiley & Sons, Ltd.

7 CFR 984.48 - Marketing estimates and recommendations.

Science.gov (United States)

2010-01-01

...; (4) The Board's estimate of the trade demand for such marketing year for shelled and inshell walnuts, taking into consideration trade inventory, imports, prices, competing nut supplies, and other factors; (5... pursuant to § 984.56, when it determines that the quantity of reserve walnuts that may be exported should...

Can rarefaction be used to estimate song repertoire size in birds?

Directory of Open Access Journals (Sweden)

Kathleen R. PESHEK, Daniel T. BLUMSTEIN

2011-06-01

Full Text Available Song repertoire size is the number of distinct syllables, phrases, or song types produced by an individual or population. Repertoire size estimation is particularly difficult for species that produce highly variable songs and those that produce many song types. Estimating repertoire size is important for ecological and evolutionary studies of speciation, studies of sexual selection, as well as studies of how species may adapt their songs to various acoustic environments. There are several methods to estimate repertoire size, however prior studies discovered that all but a full numerical count of song types might have substantial inaccuracies associated with them. We evaluated a somewhat novel approach to estimate repertoire size—rarefaction; a technique ecologists use to measure species diversity on individual and population levels. Using the syllables within American robins’ Turdus migratorius repertoire, we compared the most commonly used techniques of estimating repertoires to the results of a rarefaction analysis. American robins have elaborate and unique songs with few syllables shared between individuals, and there is no evidence that robins mimic their neighbors. Thus, they are an ideal system in which to compare techniques. We found that the rarefaction technique results resembled that of the numerical count, and were better than two alternative methods (behavioral accumulation curves, and capture-recapture to estimate syllable repertoire size. Future estimates of repertoire size, particularly in vocally complex species, may benefit from using rarefaction techniques when numerical counts are unable to be performed [Current Zoology 57 (3: 300–306, 2011].

Estimating the average grain size of metals - approved standard 1969

International Nuclear Information System (INIS)

Anon.

1975-01-01

These methods cover procedures for estimating and rules for expressing the average grain size of all metals and consisting entirely, or principally, of a single phase. The methods may also be used for any structures having appearances similar to those of the metallic structures shown in the comparison charts. The three basic procedures for grain size estimation which are discussed are comparison procedure, intercept (or Heyn) procedure, and planimetric (or Jeffries) procedure. For specimens consisting of equiaxed grains, the method of comparing the specimen with a standard chart is most convenient and is sufficiently accurate for most commercial purposes. For high degrees of accuracy in estimating grain size, the intercept or planimetric procedures may be used

Estimation of portion size in children's dietary assessment: lessons learnt.

Science.gov (United States)

Foster, E; Adamson, A J; Anderson, A S; Barton, K L; Wrieden, W L

2009-02-01

Assessing the dietary intake of young children is challenging. In any 1 day, children may have several carers responsible for providing them with their dietary requirements, and once children reach school age, traditional methods such as weighing all items consumed become impractical. As an alternative to weighed records, food portion size assessment tools are available to assist subjects in estimating the amounts of foods consumed. Existing food photographs designed for use with adults and based on adult portion sizes have been found to be inappropriate for use with children. This article presents a review and summary of a body of work carried out to improve the estimation of portion sizes consumed by children. Feasibility work was undertaken to determine the accuracy and precision of three portion size assessment tools; food photographs, food models and a computer-based Interactive Portion Size Assessment System (IPSAS). These tools were based on portion sizes served to children during the National Diet and Nutrition Survey. As children often do not consume all of the food served to them, smaller portions were included in each tool for estimation of leftovers. The tools covered 22 foods, which children commonly consume. Children were served known amounts of each food and leftovers were recorded. They were then asked to estimate both the amount of food that they were served and the amount of any food leftover. Children were found to estimate food portion size with an accuracy approaching that of adults using both the food photographs and IPSAS. Further development is underway to increase the number of food photographs and to develop IPSAS to cover a much wider range of foods and to validate the use of these tools in a 'real life' setting.

Best-Estimates in Bond Markets with Reinvestment Risk

Directory of Open Access Journals (Sweden)

Anne MacKay

2015-07-01

Full Text Available The concept of best-estimate, prescribed by regulators to value insurance liabilities for accounting and solvency purposes, has recently been discussed extensively in the industry and related academic literature. To differentiate hedgeable and non-hedgeable risks in a general case, recent literature defines best-estimates using orthogonal projections of a claim on the space of replicable payoffs. In this paper, we apply this concept of best-estimate to long-maturity claims in a market with reinvestment risk, since in this case the total liability cannot easily be separated into hedgeable and non-hedgeable parts. We assume that a limited number of short-maturity bonds are traded, and derive the best-estimate price of bonds with longer maturities, thus obtaining a best-estimate yield curve. We therefore use the multifactor Vasiˇcek model and derive within this framework closed-form expressions for the best-estimate prices of long-term bonds.

Estimating farmers’ productive and marketing inefficiency: an application to vegetable producers in Benin

NARCIS (Netherlands)

Singbo, A.G.; Oude Lansink, A.G.J.M.; Emvalomatis, G.

2014-01-01

This paper estimates the technical and marketing inefficiency of a sample of urban vegetable producers in Benin. Marketing inefficiency is defined as the failure of farmers to achieve better marketing output and is reflected in lower output price indices. The study proposes a Russell-type measure of

Audit Firm Size and Market Price Per Share of Quoted Companies in Nigeria

Directory of Open Access Journals (Sweden)

Augustine O. Okolie

2014-05-01

Full Text Available This study investigates the influence which audit firm size exerts on the market value per share of companies in Nigeria. Based on a sample of 342 companies – year observations from the NSE and applying audit firm size as a measure, comprehensive multivariate analyses were conducted on archival data covering 2006 – 2011. The result showed that audit firm size exerts significant relationship and significantly influences market price per share of the companies in the sample. It is suggested that companies in Nigeria should improve their earnings quality only through sales growth and cost control strategies and present distinct reports on earnings quality. Furthermore, company auditors should issue Integrated Audit Quality Assurance Reports based on earnings quality assessment, statutorily backed by earnings monitoring of companies in Nigeria while regulatory agencies should issue authoritative codes of best practice in Nigeria.

The Relationship between Marketing Strategy and Marketing Channels of Communication

OpenAIRE

Sayed Masud Sayedi; Hassan Soltani; Majid Keshavarz

2014-01-01

The overall objective of this study is to investigate the relationship between the expansion of marketing channels and marketing strategy is the first to examine the process of a questionnaire containing 19 questions was used as the existing standard. The research population, employees of manufacturing companies and trading company in Iran that their number is 1176 people. Sample size using the formula by including sampling error was estimated at 0.05 confidence level 0.95 times the number of...

The influence of personal BMI on body size estimations and sensitivity to body size change in anorexia spectrum disorders.

OpenAIRE

Cornelissen, Katri; Bester, Andre; Cairns, Paul; Tovee, Martin; Cornelissen, Piers

2015-01-01

In this cross-sectional study, we investigated the influence of personal BMI on body size estimation in 42 women who have symptoms of anorexia (referred to henceforth as anorexia spectrum disorders, ANSD), and 100 healthy controls. Low BMI control participants over-estimate their size and high BMI controls under-estimate, a pattern which is predicted by a perceptual phenomenon called contraction bias. In addition, control participants' sensitivity to size change declines as their BMI increase...

Conditional CAPM in the Brazilian Market: a study of the Moment, Size and Book to Market effects between 1995 and 2008

Directory of Open Access Journals (Sweden)

Frederico Valle e Flister

2011-03-01

Full Text Available This work investigates the ability of the conditional CAPM to explain anomalous returns related to momentum, size and book-to-market effects using Lewellen and Nagel’s (2006 methodology in the Brazilian stock market. To this end we studied a sample of Bovespa’s stocks in a monthly basis from July 1995 to June 2008. The results indicate that only the book-to-market effect presents statistical significance. The conditional model, tested from time series of 12 months, also showed no significant gains in relation to the unconditional form. However, there are evidences that betas do vary over time, suggesting that the sample size on beta calculations may influence portfolio choices, i.e., the evidence of variation in betas over time means that analysis based on the CAPM should be cautious when using unconditional models.

Estimating Exchange Market Pressure and the Degree of Exchange Market Intervention for Finland during the Floating Exchange Rate Regime

OpenAIRE

Pösö, Mika; Spolander, Mikko

1997-01-01

In this paper, we use a fairly simple monetary macro model to calculate the quarterly measures of exchange market pressure and the degree of the Bank of Finland's intervention during the time the markka was floated. Exchange market pressure measures the size of the exchange rate change that would have occurred if the central bank had unexpectedly refrained from intervening in the foreign exchange market. Intervention activity of the central bank is measured as the proportion of exchange marke...

Children's estimates of food portion size: the development and evaluation of three portion size assessment tools for use with children.

Science.gov (United States)

Foster, E; Matthews, J N S; Lloyd, J; Marshall, L; Mathers, J C; Nelson, M; Barton, K L; Wrieden, W L; Cornelissen, P; Harris, J; Adamson, A J

2008-01-01

A number of methods have been developed to assist subjects in providing an estimate of portion size but their application in improving portion size estimation by children has not been investigated systematically. The aim was to develop portion size assessment tools for use with children and to assess the accuracy of children's estimates of portion size using the tools. The tools were food photographs, food models and an interactive portion size assessment system (IPSAS). Children (n 201), aged 4-16 years, were supplied with known quantities of food to eat, in school. Food leftovers were weighed. Children estimated the amount of each food using each tool, 24 h after consuming the food. The age-specific portion sizes represented were based on portion sizes consumed by children in a national survey. Significant differences were found between the accuracy of estimates using the three tools. Children of all ages performed well using the IPSAS and food photographs. The accuracy and precision of estimates made using the food models were poor. For all tools, estimates of the amount of food served were more accurate than estimates of the amount consumed. Issues relating to reporting of foods left over which impact on estimates of the amounts of foods actually consumed require further study. The IPSAS has shown potential for assessment of dietary intake with children. Before practical application in assessment of dietary intake of children the tool would need to be expanded to cover a wider range of foods and to be validated in a 'real-life' situation.

Brand market positions estimation and defining the strategic targets of its development

OpenAIRE

S.M. Makhnusha

2010-01-01

In this article the author generalizes the concept of brand characteristics which influenceits profitability and market positions. An approach to brand market positions estimation anddefining the strategic targets of its development is proposed.Keywords: brand, brand expansion, brand extension, brand value, brand power, brandrelevance, brand awareness.

Size-based estimation of the status of fish stocks: simulation analysis and comparison with age-based estimations

DEFF Research Database (Denmark)

Kokkalis, Alexandros; Thygesen, Uffe Høgsbro; Nielsen, Anders

, were investigated and our estimations were compared to the ICES advice. Only size-specific catch data were used, in order to emulate data limited situations. The simulation analysis reveals that the status of the stock, i.e. F/Fmsy, is estimated more accurately than the fishing mortality F itself....... Specific knowledge of the natural mortality improves the estimation more than having information about all other life history parameters. Our approach gives, at least qualitatively, an estimated stock status which is similar to the results of an age-based assessment. Since our approach only uses size...

Size Estimates in Inverse Problems

KAUST Repository

Di Cristo, Michele

2014-01-06

Detection of inclusions or obstacles inside a body by boundary measurements is an inverse problems very useful in practical applications. When only finite numbers of measurements are available, we try to detect some information on the embedded object such as its size. In this talk we review some recent results on several inverse problems. The idea is to provide constructive upper and lower estimates of the area/volume of the unknown defect in terms of a quantity related to the work that can be expressed with the available boundary data.

COMPANY SIZE, TRADING ACTIVITY AND LIQUIDITY AS A DETERMINANTS OF CROSS-SECTIONAL MOMENTUM TRADING STRATEGY ON RUSSIAN STOCK MARKET

Directory of Open Access Journals (Sweden)

Teplova T. V.

2014-06-01

Full Text Available Momentum-effect has many interpretations in the practice of investing and in understanding of anomalies in asset prices. We consider a Cross-Sectional momentum effects and the corresponding two medium-term (3 months or more trading strategies that are different from the trend following rules for individual assets. We tested four hypothesis deals with cross-sectional momentum effect on the Russian stock market and the possibility of building a self-financing (long-short trading strategy at three time horizon (stock market growth from 2004 until mid 2008, financial crisis and post-crisis periods. It is shown that for the Russian market cross-sectional momentum strategy with partly rebalanced portfolio maximizing portfolio return (134 stocks listed from 2004 to 2014 in the few Russian stock exchanges should be based on the three-month formation period and three-month holding period periods (3/1/3. We have identified elements of profit-maximizing momentum strategy: three time windows and determinants of assets. Monthly average return of arbitrage strategy is estimated at 1.5 % for 134 common shares. Implementation of the strategy for the post-crisis period does not allow to maximize profit. For 6-month and more investment windows it gets the advantage of reverse strategy (opening long positions in stocks with low investment results and short position for assets with high relative returns. Fundamental parameters of the issuer (size of companies like market capitalization and two measures of liquidity (trading activity and transaction costs like bid-ask spread are significant to maximize portfolio performance (we prove the growth of monthly average return ranging from 1.5 to 2.5 %. We find that size and liquidity control momentum strategy can earn positive profits in Russian stock market, larger than naïve momentum.

Determining Sample Size for Accurate Estimation of the Squared Multiple Correlation Coefficient.

Science.gov (United States)

Algina, James; Olejnik, Stephen

2000-01-01

Discusses determining sample size for estimation of the squared multiple correlation coefficient and presents regression equations that permit determination of the sample size for estimating this parameter for up to 20 predictor variables. (SLD)

Strategic sizing of energy storage facilities in electricity markets

DEFF Research Database (Denmark)

Nasrolahpour, Ehsan; Kazempour, Seyyedjalal; Zareipour, Hamidreza

2016-01-01

This paper proposes a model to determine the optimasize of an energy storage facility from a strategic investor’s perspective. This investor seeks to maximize its profit through making strategic planning, i.e., storage sizing, and strategic operational, i.e., offering and bidding, decisions. We...... consider the uncertainties associated with rival generators’ offering strategies and future load levels in the proposed model. The strategic investment decisions include the sizes of charging device, discharging device and energy reservoir. The proposed model is a stochastic bi-level optimization problem......; the planning and operation decisions are made in the upper-level, and market clearing is modeled in the lower-level under different operating scenarios. To make the proposed model computationally tractable, an iterative solution technique based on Benders’ decomposition is implemented. This provides a master...

Estimating search engine index size variability: a 9-year longitudinal study.

Science.gov (United States)

van den Bosch, Antal; Bogers, Toine; de Kunder, Maurice

One of the determining factors of the quality of Web search engines is the size of their index. In addition to its influence on search result quality, the size of the indexed Web can also tell us something about which parts of the WWW are directly accessible to the everyday user. We propose a novel method of estimating the size of a Web search engine's index by extrapolating from document frequencies of words observed in a large static corpus of Web pages. In addition, we provide a unique longitudinal perspective on the size of Google and Bing's indices over a nine-year period, from March 2006 until January 2015. We find that index size estimates of these two search engines tend to vary dramatically over time, with Google generally possessing a larger index than Bing. This result raises doubts about the reliability of previous one-off estimates of the size of the indexed Web. We find that much, if not all of this variability can be explained by changes in the indexing and ranking infrastructure of Google and Bing. This casts further doubt on whether Web search engines can be used reliably for cross-sectional webometric studies.

Reliability of different mark-recapture methods for population size estimation tested against reference population sizes constructed from field data.

Directory of Open Access Journals (Sweden)

Annegret Grimm

Full Text Available Reliable estimates of population size are fundamental in many ecological studies and biodiversity conservation. Selecting appropriate methods to estimate abundance is often very difficult, especially if data are scarce. Most studies concerning the reliability of different estimators used simulation data based on assumptions about capture variability that do not necessarily reflect conditions in natural populations. Here, we used data from an intensively studied closed population of the arboreal gecko Gehyra variegata to construct reference population sizes for assessing twelve different population size estimators in terms of bias, precision, accuracy, and their 95%-confidence intervals. Two of the reference populations reflect natural biological entities, whereas the other reference populations reflect artificial subsets of the population. Since individual heterogeneity was assumed, we tested modifications of the Lincoln-Petersen estimator, a set of models in programs MARK and CARE-2, and a truncated geometric distribution. Ranking of methods was similar across criteria. Models accounting for individual heterogeneity performed best in all assessment criteria. For populations from heterogeneous habitats without obvious covariates explaining individual heterogeneity, we recommend using the moment estimator or the interpolated jackknife estimator (both implemented in CAPTURE/MARK. If data for capture frequencies are substantial, we recommend the sample coverage or the estimating equation (both models implemented in CARE-2. Depending on the distribution of catchabilities, our proposed multiple Lincoln-Petersen and a truncated geometric distribution obtained comparably good results. The former usually resulted in a minimum population size and the latter can be recommended when there is a long tail of low capture probabilities. Models with covariates and mixture models performed poorly. Our approach identified suitable methods and extended options to

Value at risk estimation with entropy-based wavelet analysis in exchange markets

Science.gov (United States)

He, Kaijian; Wang, Lijun; Zou, Yingchao; Lai, Kin Keung

2014-08-01

In recent years, exchange markets are increasingly integrated together. Fluctuations and risks across different exchange markets exhibit co-moving and complex dynamics. In this paper we propose the entropy-based multivariate wavelet based approaches to analyze the multiscale characteristic in the multidimensional domain and improve further the Value at Risk estimation reliability. Wavelet analysis has been introduced to construct the entropy-based Multiscale Portfolio Value at Risk estimation algorithm to account for the multiscale dynamic correlation. The entropy measure has been proposed as the more effective measure with the error minimization principle to select the best basis when determining the wavelet families and the decomposition level to use. The empirical studies conducted in this paper have provided positive evidence as to the superior performance of the proposed approach, using the closely related Chinese Renminbi and European Euro exchange market.

Children's accuracy of portion size estimation using digital food images: effects of interface design and size of image on computer screen.

Science.gov (United States)

Baranowski, Tom; Baranowski, Janice C; Watson, Kathleen B; Martin, Shelby; Beltran, Alicia; Islam, Noemi; Dadabhoy, Hafza; Adame, Su-heyla; Cullen, Karen; Thompson, Debbe; Buday, Richard; Subar, Amy

2011-03-01

To test the effect of image size and presence of size cues on the accuracy of portion size estimation by children. Children were randomly assigned to seeing images with or without food size cues (utensils and checked tablecloth) and were presented with sixteen food models (foods commonly eaten by children) in varying portion sizes, one at a time. They estimated each food model's portion size by selecting a digital food image. The same food images were presented in two ways: (i) as small, graduated portion size images all on one screen or (ii) by scrolling across large, graduated portion size images, one per sequential screen. Laboratory-based with computer and food models. Volunteer multi-ethnic sample of 120 children, equally distributed by gender and ages (8 to 13 years) in 2008-2009. Average percentage of correctly classified foods was 60·3 %. There were no differences in accuracy by any design factor or demographic characteristic. Multiple small pictures on the screen at once took half the time to estimate portion size compared with scrolling through large pictures. Larger pictures had more overestimation of size. Multiple images of successively larger portion sizes of a food on one computer screen facilitated quicker portion size responses with no decrease in accuracy. This is the method of choice for portion size estimation on a computer.

Using Empirical Data to Estimate Potential Functions in Commodity Markets: Some Initial Results

Science.gov (United States)

Shen, C.; Haven, E.

2017-12-01

This paper focuses on estimating real and quantum potentials from financial commodities. The log returns of six common commodities are considered. We find that some phenomena, such as the vertical potential walls and the time scale issue of the variation on returns, also exists in commodity markets. By comparing the quantum and classical potentials, we attempt to demonstrate that the information within these two types of potentials is different. We believe this empirical result is consistent with the theoretical assumption that quantum potentials (when embedded into social science contexts) may contain some social cognitive or market psychological information, while classical potentials mainly reflect `hard' market conditions. We also compare the two potential forces and explore their relationship by simply estimating the Pearson correlation between them. The Medium or weak interaction effect may indicate that the cognitive system among traders may be affected by those `hard' market conditions.

Estimating time-varying conditional correlations between stock and foreign exchange markets

Science.gov (United States)

Tastan, Hüseyin

2006-02-01

This study explores the dynamic interaction between stock market returns and changes in nominal exchange rates. Many financial variables are known to exhibit fat tails and autoregressive variance structure. It is well-known that unconditional covariance and correlation coefficients also vary significantly over time and multivariate generalized autoregressive model (MGARCH) is able to capture the time-varying variance-covariance matrix for stock market returns and changes in exchange rates. The model is applied to daily Euro-Dollar exchange rates and two stock market indexes from the US economy: Dow-Jones Industrial Average Index and S&P500 Index. The news impact surfaces are also drawn based on the model estimates to see the effects of idiosyncratic shocks in respective markets.

The Use of Market Feasibility Studies in the Restaurant Industry for Small and Medium-sized Restaurants

OpenAIRE

Kolster, Maria

2017-01-01

The goals of this thesis are to provide the reader with new information about market feasibility studies in the restaurant industry and to design a market feasibility template for the international restaurant industry which can be used for small and medium-sized restaurants before entering the market. The objectives are to define the ideal factors of a market feasibility study for the international restaurant industry, to learn and become an expert in feasibility studies for the restaurant i...

Comparison of known food weights with image-based portion-size automated estimation and adolescents' self-reported portion size.

Science.gov (United States)

Lee, Christina D; Chae, Junghoon; Schap, TusaRebecca E; Kerr, Deborah A; Delp, Edward J; Ebert, David S; Boushey, Carol J

2012-03-01

Diet is a critical element of diabetes self-management. An emerging area of research is the use of images for dietary records using mobile telephones with embedded cameras. These tools are being designed to reduce user burden and to improve accuracy of portion-size estimation through automation. The objectives of this study were to (1) assess the error of automatically determined portion weights compared to known portion weights of foods and (2) to compare the error between automation and human. Adolescents (n = 15) captured images of their eating occasions over a 24 h period. All foods and beverages served were weighed. Adolescents self-reported portion sizes for one meal. Image analysis was used to estimate portion weights. Data analysis compared known weights, automated weights, and self-reported portions. For the 19 foods, the mean ratio of automated weight estimate to known weight ranged from 0.89 to 4.61, and 9 foods were within 0.80 to 1.20. The largest error was for lettuce and the most accurate was strawberry jam. The children were fairly accurate with portion estimates for two foods (sausage links, toast) using one type of estimation aid and two foods (sausage links, scrambled eggs) using another aid. The automated method was fairly accurate for two foods (sausage links, jam); however, the 95% confidence intervals for the automated estimates were consistently narrower than human estimates. The ability of humans to estimate portion sizes of foods remains a problem and a perceived burden. Errors in automated portion-size estimation can be systematically addressed while minimizing the burden on people. Future applications that take over the burden of these processes may translate to better diabetes self-management. © 2012 Diabetes Technology Society.

Panel data estimates of the production function and product and labor market imperfections

NARCIS (Netherlands)

Dobbelaere, S.; Mairesse, J.

2013-01-01

Consistent with two models of imperfect competition in the labor market-the efficient bargaining model and the monopsony model-we provide two extensions of a microeconomic version of Hall's framework for estimating price-cost margins. We show that both product and labor market imperfections generate

Optimum sample size to estimate mean parasite abundance in fish parasite surveys

Directory of Open Access Journals (Sweden)

Shvydka S.

2018-03-01

Full Text Available To reach ethically and scientifically valid mean abundance values in parasitological and epidemiological studies this paper considers analytic and simulation approaches for sample size determination. The sample size estimation was carried out by applying mathematical formula with predetermined precision level and parameter of the negative binomial distribution estimated from the empirical data. A simulation approach to optimum sample size determination aimed at the estimation of true value of the mean abundance and its confidence interval (CI was based on the Bag of Little Bootstraps (BLB. The abundance of two species of monogenean parasites Ligophorus cephali and L. mediterraneus from Mugil cephalus across the Azov-Black Seas localities were subjected to the analysis. The dispersion pattern of both helminth species could be characterized as a highly aggregated distribution with the variance being substantially larger than the mean abundance. The holistic approach applied here offers a wide range of appropriate methods in searching for the optimum sample size and the understanding about the expected precision level of the mean. Given the superior performance of the BLB relative to formulae with its few assumptions, the bootstrap procedure is the preferred method. Two important assessments were performed in the present study: i based on CIs width a reasonable precision level for the mean abundance in parasitological surveys of Ligophorus spp. could be chosen between 0.8 and 0.5 with 1.6 and 1x mean of the CIs width, and ii the sample size equal 80 or more host individuals allows accurate and precise estimation of mean abundance. Meanwhile for the host sample size in range between 25 and 40 individuals, the median estimates showed minimal bias but the sampling distribution skewed to the low values; a sample size of 10 host individuals yielded to unreliable estimates.

Parabolic Free Boundary Price Formation Models Under Market Size Fluctuations

KAUST Repository

Markowich, Peter A.

2016-10-04

In this paper we propose an extension of the Lasry-Lions price formation model which includes uctuations of the numbers of buyers and vendors. We analyze the model in the case of deterministic and stochastic market size uctuations and present results on the long time asymptotic behavior and numerical evidence and conjectures on periodic, almost periodic, and stochastic uctuations. The numerical simulations extend the theoretical statements and give further insights into price formation dynamics.

Mean size estimation yields left-side bias: Role of attention on perceptual averaging.

Science.gov (United States)

Li, Kuei-An; Yeh, Su-Ling

2017-11-01

The human visual system can estimate mean size of a set of items effectively; however, little is known about whether information on each visual field contributes equally to the mean size estimation. In this study, we examined whether a left-side bias (LSB)-perceptual judgment tends to depend more heavily on left visual field's inputs-affects mean size estimation. Participants were instructed to estimate the mean size of 16 spots. In half of the trials, the mean size of the spots on the left side was larger than that on the right side (the left-larger condition) and vice versa (the right-larger condition). Our results illustrated an LSB: A larger estimated mean size was found in the left-larger condition than in the right-larger condition (Experiment 1), and the LSB vanished when participants' attention was effectively cued to the right side (Experiment 2b). Furthermore, the magnitude of LSB increased with stimulus-onset asynchrony (SOA), when spots on the left side were presented earlier than the right side. In contrast, the LSB vanished and then induced a reversed effect with SOA when spots on the right side were presented earlier (Experiment 3). This study offers the first piece of evidence suggesting that LSB does have a significant influence on mean size estimation of a group of items, which is induced by a leftward attentional bias that enhances the prior entry effect on the left side.

Size and liquidity effects in Nigeria: an industrial sector study

OpenAIRE

Hearn, Bruce

2013-01-01

This study estimates liquidity premiums using the recently developed Liu (2006) measure within a multifactor capital asset pricing model (CAPM) including size premiums and a time varying parameter model for the West African emerging market of Nigeria. The evidence suggests that liquidity factors are relevant only for financial and basic materials sector stocks while size factor is more generally relevant in explaining the cross section of stock returns in the Nigerian domestic equity market....

The relationship between size, book-to-market equity ratio, earnings–price ratio, and return for the Tehran stock Exchange

Directory of Open Access Journals (Sweden)

Mohammad Ali Sadeghi Lafmejani

2016-01-01

Full Text Available This paper presents an empirical investigation to determine whether or there is any difference between the returns of two value and growth portfolios, sorted by price-to-earnings (P/E and price-to-book value (P/BV, in terms of the ratios of market sensitivity to index (β, firm size and market liquidity in listed firms in Tehran Stock Exchange (TSE over the period 2001-2008. The selected firms were collected from those with existing two-consecutive positive P/E and P/BV ratios and by excluding financial and holding firms. There were five independent variables for the proposed study of this paper including P/E, P/B, market size, market sensitivity beta (β and market liquidity. In each year, we first sort firms in non-decreasing order and setup four set of portfolios with equal firms. Therefore, the first portfolio with the lowest P/E ratio is called value portfolio and the last one with the highest P/E ratio is called growth portfolio. This process was repeated based on P/BV ratio to determine value and growth portfolios, accordingly. The study investigated the characteristics of two portfolios based on firm size, β and liquidity. The study has implemented t-student and Levin’s test to examine different hypotheses and the results have indicated mix effects of market sensitivity, firm size and market liquidity on returns of the firms in various periods.

Marketing RECs in the US

International Nuclear Information System (INIS)

Bird, L.; Holt, E.

2005-01-01

This short paper was derived from a major report funded by the US Department of Energy (DOE) Office of Energy and Renewable Energy (EERE). It discusses the benefits to be derived in the form of renewable energy certificates (RECs) awarded for generating electric power from renewable energy sources. Their flexibility and international acceptance makes RECs the currency of the renewable international power markets. The size and potential value of US REC markets is estimated and key issues and challenges that will influence or govern future market developments are identified

US market potential for small and medium-sized nuclear reactors

International Nuclear Information System (INIS)

Hardie, R.W.; Jackson, S.V.

1988-01-01

This paper presents the results of on-site interviews with representatives of 23 investor-owned utilities and 3 publicly-owned utilities. The purpose of the interviews was to obtain information on utilities' attitudes towards small and medium-sized power plants and towards building new nuclear plants in general. Most of the utilities interviewed preferred power plants smaller than the ones currently being offered, as long as the smaller plants did not incur a major economic penalty. However, according to the utilities interviewed, without changes in the current environment it is unlikely that there will be a significant market for new nuclear plants of any size. A trend in the utility industry towards generating companies appears to be a positive step. (orig.)

US market potential for small and medium-sized nuclear reactors

International Nuclear Information System (INIS)

Hardie, R.W.; Jackson, S.V.

1987-01-01

This paper presents the results of on-site interviews with representatives of 23 investor-owned utilities and 3 publicly-owned utilities. The purpose of the interviews was to obtain information on utilities' attitudes toward small and medium-sized power plants and towards building new nuclear plants in general. Most of the utilities interviewed preferred power plants smaller than the ones currently being offered, as long as the smaller plants did not incur a major economic penalty. However, according to the utilities interviewed, without changes in the current environment it is unlikely that there will be a significant market for new nuclear plants of any size. A trend in the utility industry towards generating companies appears to be a positive step. (author)

Estimating minimum polycrystalline aggregate size for macroscopic material homogeneity

International Nuclear Information System (INIS)

Kovac, M.; Simonovski, I.; Cizelj, L.

2002-01-01

During severe accidents the pressure boundary of reactor coolant system can be subjected to extreme loadings, which might cause failure. Reliable estimation of the extreme deformations can be crucial to determine the consequences of severe accidents. Important drawback of classical continuum mechanics is idealization of inhomogenous microstructure of materials. Classical continuum mechanics therefore cannot predict accurately the differences between measured responses of specimens, which are different in size but geometrical similar (size effect). A numerical approach, which models elastic-plastic behavior on mesoscopic level, is proposed to estimate minimum size of polycrystalline aggregate above which it can be considered macroscopically homogeneous. The main idea is to divide continuum into a set of sub-continua. Analysis of macroscopic element is divided into modeling the random grain structure (using Voronoi tessellation and random orientation of crystal lattice) and calculation of strain/stress field. Finite element method is used to obtain numerical solutions of strain and stress fields. The analysis is limited to 2D models.(author)

Webometrics: Some Critical Issues of WWW Size Estimation Methods

Directory of Open Access Journals (Sweden)

Srinivasan Mohana Arunachalam

2018-04-01

Full Text Available The number of webpages in the Internet has increased tremendously over the last two decades however only a part of it is indexed by various search engines. This small portion is the indexable web of the Internet and can be usually reachable from a Search Engine. Search engines play a big role in making the World Wide Web accessible to the end user, and how much of the World Wide Web is accessible on the size of the search engine’s index. Researchers have proposed several ways to estimate this size of the indexable web using search engines with and without privileged access to the search engine’s database. Our report provides a summary of methods used in the last two decades to estimate the size of the World Wide Web, as well as describe how this knowledge can be used in other aspects/tasks concerning the World Wide Web.

Using prediction markets to estimate the reproducibility of scientific research

Science.gov (United States)

Dreber, Anna; Pfeiffer, Thomas; Almenberg, Johan; Isaksson, Siri; Wilson, Brad; Chen, Yiling; Nosek, Brian A.; Johannesson, Magnus

2015-01-01

Concerns about a lack of reproducibility of statistically significant results have recently been raised in many fields, and it has been argued that this lack comes at substantial economic costs. We here report the results from prediction markets set up to quantify the reproducibility of 44 studies published in prominent psychology journals and replicated in the Reproducibility Project: Psychology. The prediction markets predict the outcomes of the replications well and outperform a survey of market participants’ individual forecasts. This shows that prediction markets are a promising tool for assessing the reproducibility of published scientific results. The prediction markets also allow us to estimate probabilities for the hypotheses being true at different testing stages, which provides valuable information regarding the temporal dynamics of scientific discovery. We find that the hypotheses being tested in psychology typically have low prior probabilities of being true (median, 9%) and that a “statistically significant” finding needs to be confirmed in a well-powered replication to have a high probability of being true. We argue that prediction markets could be used to obtain speedy information about reproducibility at low cost and could potentially even be used to determine which studies to replicate to optimally allocate limited resources into replications. PMID:26553988

Using prediction markets to estimate the reproducibility of scientific research.

Science.gov (United States)

Dreber, Anna; Pfeiffer, Thomas; Almenberg, Johan; Isaksson, Siri; Wilson, Brad; Chen, Yiling; Nosek, Brian A; Johannesson, Magnus

2015-12-15

Concerns about a lack of reproducibility of statistically significant results have recently been raised in many fields, and it has been argued that this lack comes at substantial economic costs. We here report the results from prediction markets set up to quantify the reproducibility of 44 studies published in prominent psychology journals and replicated in the Reproducibility Project: Psychology. The prediction markets predict the outcomes of the replications well and outperform a survey of market participants' individual forecasts. This shows that prediction markets are a promising tool for assessing the reproducibility of published scientific results. The prediction markets also allow us to estimate probabilities for the hypotheses being true at different testing stages, which provides valuable information regarding the temporal dynamics of scientific discovery. We find that the hypotheses being tested in psychology typically have low prior probabilities of being true (median, 9%) and that a "statistically significant" finding needs to be confirmed in a well-powered replication to have a high probability of being true. We argue that prediction markets could be used to obtain speedy information about reproducibility at low cost and could potentially even be used to determine which studies to replicate to optimally allocate limited resources into replications.

The influence of CEO gender on market orientation and performance in service small and medium-sized service businesses

NARCIS (Netherlands)

Davis, Peter S.; Babakus, Emin; Englis-Danskin, Paula; Pett, Tim

2010-01-01

This study examines the effects of CEO gender on market orientation and performance (growth and profitability) among a sample of small and medium-sized service businesses. Gender was found to have significant indirect effects (via market orientation) on both market performance (growth) and financial

Estimation of myocardial infarct size by vectocardiography

International Nuclear Information System (INIS)

Takimiya, Akihiko

1987-01-01

Correlations between the vectorcardiogram (VCG) indice and infarct size (% defect) obtained from myocardial emission computed tomography with thallium-201 were studied in 45 patients with old infero-posterior myocardial infarction. The patients were divided into two groups, one consisting of eight patients who showed abnormal superior deviation of the QRS loop in a counterclockwise rotation beyond 30 msec in the frontal plane of VCG (referred to hereafter as CCW group), and another a non-CCW group consisting of 37 patients. The results obtained were as follows. (1) In the non-CCW group, there were significant negative correlations between the elevation and the Y-axial component of each instantaneous vector of the QRS loop at 30 msec, 35 msec, 40 msec, 45 msec, and between the Y-axial component of 50 msec instantaneous vector and the % defect. The correlation for both the elevation and the Y-axial component was closest at 40 msec, and there was most significantly close correlation between the elevation of 40 msec instantaneous vector and the % defect. (2) In the non-CCW group, there was also a significant correlation between the elevation of QRS area vector and the % defect. (3) In the CCW group, the infarct size could be estimated by the elevation of 30 msec instantaneous vector. An association with left anterior fascicular block was also indicated in the CCW group. (4) In infero-posterior myocardial infarction, the infarct size can be estimated using these VCG indices. (author)

Long-Term Effects of School Size on Students' Outcomes

DEFF Research Database (Denmark)

Humlum, Maria Knoth; Smith, Nina

We estimate the effect of school size on students' long-term outcomes such as high school completion, being out of the labor market, and earnings at the age of 30. We use rich register data on the entire population of Danish children attending grade 9 in the period 1986-2004. This allows us...... school size and alternative measures of long-term success in the educational system and the labor market. The positive impact of school size seems mainly to be driven by boys, students from families with a low educational level and students attending schools in urban areas....

A simple method for estimating the size of nuclei on fractal surfaces

Science.gov (United States)

Zeng, Qiang

2017-10-01

Determining the size of nuclei on complex surfaces remains a big challenge in aspects of biological, material and chemical engineering. Here the author reported a simple method to estimate the size of the nuclei in contact with complex (fractal) surfaces. The established approach was based on the assumptions of contact area proportionality for determining nucleation density and the scaling congruence between nuclei and surfaces for identifying contact regimes. It showed three different regimes governing the equations for estimating the nucleation site density. Nuclei in the size large enough could eliminate the effect of fractal structure. Nuclei in the size small enough could lead to the independence of nucleation site density on fractal parameters. Only when nuclei match the fractal scales, the nucleation site density is associated with the fractal parameters and the size of the nuclei in a coupling pattern. The method was validated by the experimental data reported in the literature. The method may provide an effective way to estimate the size of nuclei on fractal surfaces, through which a number of promising applications in relative fields can be envisioned.

Sizing up arthropod genomes: an evaluation of the impact of environmental variation on genome size estimates by flow cytometry and the use of qPCR as a method of estimation.

Science.gov (United States)

Gregory, T Ryan; Nathwani, Paula; Bonnett, Tiffany R; Huber, Dezene P W

2013-09-01

A study was undertaken to evaluate both a pre-existing method and a newly proposed approach for the estimation of nuclear genome sizes in arthropods. First, concerns regarding the reliability of the well-established method of flow cytometry relating to impacts of rearing conditions on genome size estimates were examined. Contrary to previous reports, a more carefully controlled test found negligible environmental effects on genome size estimates in the fly Drosophila melanogaster. Second, a more recently touted method based on quantitative real-time PCR (qPCR) was examined in terms of ease of use, efficiency, and (most importantly) accuracy using four test species: the flies Drosophila melanogaster and Musca domestica and the beetles Tribolium castaneum and Dendroctonus ponderosa. The results of this analysis demonstrated that qPCR has the tendency to produce substantially different genome size estimates from other established techniques while also being far less efficient than existing methods.

Factors affecting potential market penetration of laser fusion power plants

International Nuclear Information System (INIS)

Deonigi, D.E.; Fraley, D.W.

1979-08-01

A mini-model has been constructed to estimate the optimal size of laser fusion power plants and to estimate the allowable cost of the first such plant in relation to the next best alternative. In estimating the costs of laser fusion, the mini-model incorporates such factors as market penetration, learning, economies of scale, system size, transmission costs, reserve requirements, development and licensing costs and site costs. The results of the mini-model simulations indicate that the optimal laser fusion plant size is approximately 3 GWe; risk considerations unincorporated in the mini-model suggest an optimal size closer to 2.5 GWe

COMPANY SIZE, TRADING ACTIVITY AND LIQUIDITY AS A DETERMINANTS OF CROSS-SECTIONAL MOMENTUM TRADING STRATEGY ON RUSSIAN STOCK MARKET. PART 2

Directory of Open Access Journals (Sweden)

Teplova T. V.

2014-09-01

Full Text Available Momentum-effect has many interpretations in the practice of investing and in understanding of anomalies in asset prices. We consider a Cross-Sectional momentum effects and the corresponding two medium-term (3 months or more trading strategies that are different from the trend following rules for individual assets. We tested four hypothesis deals with cross-sectional momentum effect on the Russian stock market and the possibility of building a self-financing (long-short trading strategy at three time horizon (stock market growth from 2004 until mid-2008, financial crisis and post-crisis periods. It is shown that for the Russian market cross-sectional momentum strategy with partly rebalanced portfolio maximizing portfolio return (134 stocks listed from 2004 to 2014 in the few Russian stock exchanges should be based on the three-month formation period and three-month holding period periods (3/1/3. We have identified elements of profit-maximizing momentum strategy: three time windows and determinants of assets. Monthly average return of arbitrage strategy is estimated at 1.5 % for 134 common shares. Implementation of the strategy for the post-crisis period does not allow to maximize profit. For 6 month and more investment windows it gets the advantage of reverse strategy (opening long positions in stocks with low investment results and short position for assets with high relative returns. Fundamental parameters of the issuer (size of companies like market capitalization and two measures of liquidity (trading activity and transaction costs like bid-ask spread are significant to maximize portfolio performance (we prove the growth of monthly average return ranging from 1.5 to 2.5 %. We find that size and liquidity control momentum strategy can earn positive profits in Russian stock market, larger than naïve momentum.

THE PREMISES OF STRATEGIC MARKETING PLANNING IMPLEMENTATION WITHIN SMALL AND MEDIUM SIZED ENTERPRISES

Directory of Open Access Journals (Sweden)

Popescu Andrei

2011-07-01

Full Text Available The main purpose of the present paper is to identify the framework and the necessary conditions for the small and medium sized enterprises (SMEs to be able to adopt the strategic marketing planning. Also, the paper aims to underline the importance of the strategic marketing planning and the manner in which the SMEs can adopt, implement and operationalize the strategic marketing planning instruments, whose correct understanding and usage ensure the capacity to generate competitive advantage, the key element both from the perspective of the fierce competition and the perspective of the future development of the SMEs. Within SMEs the implementation of marketing becomes an evident requirment, mostly due to the relationship that these have with the market, thus, leading towards market orientation of the activities, a new approach developed by the marketing vision on managing the activities from these types of organizations. Regarded upon, from the marketing perspective, the activities from the SMEs, especially the marketing activities, cannot take place randomly. Resource allocation, a characteristic of these types of organizations, and the objectives with regards to superior customer needs satisfaction and economic efficiency maximization, claim thorough plannification and deployment of the activities in a sequence that represents the implementation of a strategy previously assumed. Within this framework, the strategic marketing planning appears as a complex process employing all scientific instruments that comprise segmentation, positioning and marketing mix. Utilizing the strategic marketing planning within SMEs depends to further extend on marketing integration; process directly related with a series of factors such as the nature of the market, development stage, product type, management quality and the influences of the marketing department of the SME. The implications onto the marketing activities from SMEs are reflected upon each strategic

Class Size and Sorting in Market Equilibrium: Theory and Evidence. NBER Working Paper No. 13303

Science.gov (United States)

Urquiola, Miguel; Verhoogen, Eric

2007-01-01

This paper examines how schools choose class size and how households sort in response to those choices. Focusing on the highly liberalized Chilean education market, we develop a model in which schools are heterogeneous in an underlying productivity parameter, class size is a component of school quality, households are heterogeneous in income and…

The international food unit: a new measurement aid that can improve portion size estimation.

Science.gov (United States)

Bucher, T; Weltert, M; Rollo, M E; Smith, S P; Jia, W; Collins, C E; Sun, M

2017-09-12

Portion size education tools, aids and interventions can be effective in helping prevent weight gain. However consumers have difficulties in estimating food portion sizes and are confused by inconsistencies in measurement units and terminologies currently used. Visual cues are an important mediator of portion size estimation, but standardized measurement units are required. In the current study, we present a new food volume estimation tool and test the ability of young adults to accurately quantify food volumes. The International Food Unit™ (IFU™) is a 4x4x4 cm cube (64cm 3 ), subdivided into eight 2 cm sub-cubes for estimating smaller food volumes. Compared with currently used measures such as cups and spoons, the IFU™ standardizes estimation of food volumes with metric measures. The IFU™ design is based on binary dimensional increments and the cubic shape facilitates portion size education and training, memory and recall, and computer processing which is binary in nature. The performance of the IFU™ was tested in a randomized between-subject experiment (n = 128 adults, 66 men) that estimated volumes of 17 foods using four methods; the IFU™ cube, a deformable modelling clay cube, a household measuring cup or no aid (weight estimation). Estimation errors were compared between groups using Kruskall-Wallis tests and post-hoc comparisons. Estimation errors differed significantly between groups (H(3) = 28.48, p studies should investigate whether the IFU™ can facilitate portion size training and whether portion size education using the IFU™ is effective and sustainable without the aid. A 3-dimensional IFU™ could serve as a reference object for estimating food volume.

Billboard and its role in the marketing strategy of small and medium-sized enterprises

OpenAIRE

Mikolajová, Kamila

2013-01-01

The main objective of this work was to clarify the role billboard in the marketing strategy of small and medium-sized enterprise. The theoretical part deals with marketing and commercial communications, their mixes and process of creation. This work also analyzes the billboard as one of the types of outdoor advertising. It provides a detailed look at its advantages, disadvantages, characteristics that should be considered when choosing media. It also provides guidance on how it should look li...

Riverine based eco-tourism: Trinity River non-market benefits estimates

Science.gov (United States)

Douglas, A.J.; Taylor, J.G.

1998-01-01

California's Central Valley Project (CVP) was approved by voters in a statewide referendum in 1933. CVP referendum approval initiated funding for construction of important water development projects that had far reaching effects on regional water supplies. The construction of Trinity Dam in 1963 and the subsequent transbasin diversion of Trinity River flow was one of several CVP projects that had noteworthy adverse environmental and regional economic impacts. The Trinity River is the largest tributary of the Klamath River, and has its headwaters in the Trinity Alps of north-central California. After the construction of Trinity Dam in 1963, 90% of the Trinity River flow at Lewiston was moved to the Sacramento River via the Clear Creek Tunnel. Before 1963, the Trinity River was a major recreation resource of Northern California. The loss of streamflow has had a marked adverse impact on Trinity River-related recreation activities and the size and robustness of Trinity River salmon, steelhead, shad, and sturgeon runs. Trinity River water produces hydropower during its transit via Bureau of Reclamation canals and pumps to the northern San Joaquin Valley, where it is used for irrigated agriculture. The benefits provided by Trinity River instream flow-related environmental amenities were estimated with the travel cost method (TCM). Trinity River non-market benefits are about $406 million per annum, while the social cost of sending water down the Trinity River ranges from $17 to $42 million per annum, depending on the exact flow. We also discuss the relative magnitude of Trinity River survey data contingent value method (CVM) benefits estimates.

Estimation of Tooth Size Discrepancies among Different Malocclusion Groups

OpenAIRE

Hasija, Narender; Bala, Madhu; Goyal, Virender

2014-01-01

ABSTRACT Regards and Tribute: Late Dr Narender Hasija was a mentor and visionary in the light of knowledge and experience. We pay our regards with deepest gratitude to the departed soul to rest in peace. Bolton’s ratios help in estimating overbite, overjet relationships, the effects of contemplated extractions on posterior occlusion, incisor relationships and identification of occlusal misfit produced by tooth size discrepancies. Aim: To determine any difference in tooth size discrepancy in a...

Sample size for estimation of the Pearson correlation coefficient in cherry tomato tests

Directory of Open Access Journals (Sweden)

Bruno Giacomini Sari

2017-09-01

Full Text Available ABSTRACT: The aim of this study was to determine the required sample size for estimation of the Pearson coefficient of correlation between cherry tomato variables. Two uniformity tests were set up in a protected environment in the spring/summer of 2014. The observed variables in each plant were mean fruit length, mean fruit width, mean fruit weight, number of bunches, number of fruits per bunch, number of fruits, and total weight of fruits, with calculation of the Pearson correlation matrix between them. Sixty eight sample sizes were planned for one greenhouse and 48 for another, with the initial sample size of 10 plants, and the others were obtained by adding five plants. For each planned sample size, 3000 estimates of the Pearson correlation coefficient were obtained through bootstrap re-samplings with replacement. The sample size for each correlation coefficient was determined when the 95% confidence interval amplitude value was less than or equal to 0.4. Obtaining estimates of the Pearson correlation coefficient with high precision is difficult for parameters with a weak linear relation. Accordingly, a larger sample size is necessary to estimate them. Linear relations involving variables dealing with size and number of fruits per plant have less precision. To estimate the coefficient of correlation between productivity variables of cherry tomato, with a confidence interval of 95% equal to 0.4, it is necessary to sample 275 plants in a 250m² greenhouse, and 200 plants in a 200m² greenhouse.

Impact of Base Functional Component Types on Software Functional Size based Effort Estimation

OpenAIRE

Gencel, Cigdem; Buglione, Luigi

2008-01-01

Software effort estimation is still a significant challenge for software management. Although Functional Size Measurement (FSM) methods have been standardized and have become widely used by the software organizations, the relationship between functional size and development effort still needs further investigation. Most of the studies focus on the project cost drivers and consider total software functional size as the primary input to estimation models. In this study, we investigate whether u...

Penetration of small and medium sized food companies on foreign markets

Directory of Open Access Journals (Sweden)

Ladislav Mura

2010-01-01

Full Text Available In the world the interconnection of national economies and internationalization of economic processes occur. In turbulent changing business environment only those companies that understand the current trends in global economy may survive, develop and prosper. Therefore, the issue of internationalization for most companies becomes to be more important and the process of in­ter­na­tio­na­li­za­tion is the way how to stand this increasingly competitive environment. In presented contribution, the attention is paid to issues of internationalization of Slovak food industry enterprises such as their way of business internationalization, percentage share of foreign - trading activities on overall business activity, company evaluation of business internationalization or barriers of foreign markets pe­ne­tra­tion that researched companies have to deal with. Small and medium-sized enterprises (SMEs are the engine of the Slovak economy, generator of development, innovation, growth and they employ more than 60% of employees. Almost all businesses operating in agri-food complex have character of small and medium enterprises. The results of carried research have shown that small and medium-sized companies are considered to be successful in operation on foreign markets in surrounding European countries.

Estimating the size of non-observed economy in Croatia using the MIMIC approach

Directory of Open Access Journals (Sweden)

Vjekoslav Klarić

2011-03-01

Full Text Available This paper gives a quick overview of the approaches that have been used in the research of shadow economy, starting with the definitions of the terms “shadow economy” and “non-observed economy”, with the accent on the ISTAT/Eurostat framework. Several methods for estimating the size of the shadow economy and the non-observed economy are then presented. The emphasis is placed on the MIMIC approach, one of the methods used to estimate the size of the nonobserved economy. After a glance at the theory behind it, the MIMIC model is then applied to the Croatian economy. Considering the described characteristics of different methods, a previous estimate of the size of the non-observed economy in Croatia is chosen to provide benchmark values for the MIMIC model. Using those, the estimates of the size of non-observed economy in Croatia during the period 1998-2009 are obtained.

Estimating population size of Saddle-billed Storks Ephippiorhynchus ...

African Journals Online (AJOL)

The aim of this study was to estimate the population size within associated confidence limits using a modified mark–recapture field method. The vehicle survey, conducted shortly after rainfall in the area, did not produce results with known precision under these conditions. A repeat of this census in spring, after the peak ...

Shear-wave elastography contributes to accurate tumour size estimation when assessing small breast cancers

International Nuclear Information System (INIS)

Mullen, R.; Thompson, J.M.; Moussa, O.; Vinnicombe, S.; Evans, A.

2014-01-01

Aim: To assess whether the size of peritumoural stiffness (PTS) on shear-wave elastography (SWE) for small primary breast cancers (≤15 mm) was associated with size discrepancies between grey-scale ultrasound (GSUS) and final histological size and whether the addition of PTS size to GSUS size might result in more accurate tumour size estimation when compared to final histological size. Materials and methods: A retrospective analysis of 86 consecutive patients between August 2011 and February 2013 who underwent breast-conserving surgery for tumours of size ≤15 mm at ultrasound was carried out. The size of PTS stiffness was compared to mean GSUS size, mean histological size, and the extent of size discrepancy between GSUS and histology. PTS size and GSUS were combined and compared to the final histological size. Results: PTS of >3 mm was associated with a larger mean final histological size (16 versus 11.3 mm, p < 0.001). PTS size of >3 mm was associated with a higher frequency of underestimation of final histological size by GSUS of >5 mm (63% versus 18%, p < 0.001). The combination of PTS and GSUS size led to accurate estimation of the final histological size (p = 0.03). The size of PTS was not associated with margin involvement (p = 0.27). Conclusion: PTS extending beyond 3 mm from the grey-scale abnormality is significantly associated with underestimation of tumour size of >5 mm for small invasive breast cancers. Taking into account the size of PTS also led to accurate estimation of the final histological size. Further studies are required to assess the relationship of the extent of SWE stiffness and margin status. - Highlights: • Peritumoural stiffness of greater than 3 mm was associated with larger tumour size. • Underestimation of tumour size by ultrasound was associated with peri-tumoural stiffness size. • Combining peri-tumoural stiffness size to ultrasound produced accurate tumour size estimation

Automated nodule location and size estimation using a multi-scale Laplacian of Gaussian filtering approach.

Science.gov (United States)

Jirapatnakul, Artit C; Fotin, Sergei V; Reeves, Anthony P; Biancardi, Alberto M; Yankelevitz, David F; Henschke, Claudia I

2009-01-01

Estimation of nodule location and size is an important pre-processing step in some nodule segmentation algorithms to determine the size and location of the region of interest. Ideally, such estimation methods will consistently find the same nodule location regardless of where the the seed point (provided either manually or by a nodule detection algorithm) is placed relative to the "true" center of the nodule, and the size should be a reasonable estimate of the true nodule size. We developed a method that estimates nodule location and size using multi-scale Laplacian of Gaussian (LoG) filtering. Nodule candidates near a given seed point are found by searching for blob-like regions with high filter response. The candidates are then pruned according to filter response and location, and the remaining candidates are sorted by size and the largest candidate selected. This method was compared to a previously published template-based method. The methods were evaluated on the basis of stability of the estimated nodule location to changes in the initial seed point and how well the size estimates agreed with volumes determined by a semi-automated nodule segmentation method. The LoG method exhibited better stability to changes in the seed point, with 93% of nodules having the same estimated location even when the seed point was altered, compared to only 52% of nodules for the template-based method. Both methods also showed good agreement with sizes determined by a nodule segmentation method, with an average relative size difference of 5% and -5% for the LoG and template-based methods respectively.

Estimating fair-market value for hydrocarbon producing properties

International Nuclear Information System (INIS)

Garb, F.A.

1996-01-01

The generally accepted appraisal methods used to evaluate hydrocarbon properties and prospects were described. Fair-market-value (FMV) estimates have been used in the petroleum industry in attempts to protect a purchaser against an unwise acquisition, or conversely, to establish a just price to compensate a seller. Four methods were identified for determining FMV for hydrocarbon producing properties. They are: (1) comparative sales, (2) rule of thumb, (3) income forecast, and (4) replacement cost. The differences between oil and gas FMV and real estate FMV were explained

A Heuristic Probabilistic Approach to Estimating Size-Dependent Mobility of Nonuniform Sediment

Science.gov (United States)

Woldegiorgis, B. T.; Wu, F. C.; van Griensven, A.; Bauwens, W.

2017-12-01

Simulating the mechanism of bed sediment mobility is essential for modelling sediment dynamics. Despite the fact that many studies are carried out on this subject, they use complex mathematical formulations that are computationally expensive, and are often not easy for implementation. In order to present a simple and computationally efficient complement to detailed sediment mobility models, we developed a heuristic probabilistic approach to estimating the size-dependent mobilities of nonuniform sediment based on the pre- and post-entrainment particle size distributions (PSDs), assuming that the PSDs are lognormally distributed. The approach fits a lognormal probability density function (PDF) to the pre-entrainment PSD of bed sediment and uses the threshold particle size of incipient motion and the concept of sediment mixture to estimate the PSDs of the entrained sediment and post-entrainment bed sediment. The new approach is simple in physical sense and significantly reduces the complexity and computation time and resource required by detailed sediment mobility models. It is calibrated and validated with laboratory and field data by comparing to the size-dependent mobilities predicted with the existing empirical lognormal cumulative distribution function (CDF) approach. The novel features of the current approach are: (1) separating the entrained and non-entrained sediments by a threshold particle size, which is a modified critical particle size of incipient motion by accounting for the mixed-size effects, and (2) using the mixture-based pre- and post-entrainment PSDs to provide a continuous estimate of the size-dependent sediment mobility.

Competitive helping increases with the size of biological markets and invades defection.

Science.gov (United States)

Barclay, Pat

2011-07-21

Cooperation between unrelated individuals remains a puzzle in evolutionary biology. Recent work indicates that partner choice can select for high levels of helping. More generally, helping can be seen as but one strategy used to compete for partners within a broader biological market, yet giving within such markets has received little mathematical investigation. In the present model, individuals help others to attract attention from them and thus receive a larger share of any help actively or passively provided by those others. The evolutionarily stable level of helping increases with the size of the biological market and the degree of partner choice. Furthermore, if individuals passively produce some no-cost help to partners, competitive helping can then invade populations of non-helpers because helpers directly benefit from increasing their access to potential partners. This framework of competitive helping demonstrates how high helping can be achieved and why different populations may differ in helping levels. Copyright © 2011 Elsevier Ltd. All rights reserved.

The discrepancy between emotional vs. rational estimates of body size, actual size, and ideal body ratings: theoretical and clinical implications.

Science.gov (United States)

Thompson, J K; Dolce, J J

1989-05-01

Thirty-two asymptomatic college females were assessed on multiple aspects of body image. Subjects' estimation of the size of three body sites (waist, hips, thighs) was affected by instructional protocol. Emotional ratings, based on how they "felt" about their body, elicited ratings that were larger than actual and ideal size measures. Size ratings based on rational instructions were no different from actual sizes, but were larger than ideal ratings. There were no differences between actual and ideal sizes. The results are discussed with regard to methodological issues involved in body image research. In addition, a working hypothesis that differentiates affective/emotional from cognitive/rational aspects of body size estimation is offered to complement current theories of body image. Implications of the findings for the understanding of body image and its relationship to eating disorders are discussed.

Using the ''Epiquant'' automatic analyzer for quantitative estimation of grain size

Energy Technology Data Exchange (ETDEWEB)

Tsivirko, E I; Ulitenko, A N; Stetsenko, I A; Burova, N M [Zaporozhskij Mashinostroitel' nyj Inst. (Ukrainian SSR)

1979-01-01

Application possibility of the ''Epiquant'' automatic analyzer to estimate qualitatively austenite grain in the 18Kh2N4VA steel has been investigated. Austenite grain has been clarified using the methods of cementation, oxidation and etching of the grain boundaries. Average linear size of grain at the length of 15 mm has been determined according to the total length of grain intersection line and the number of intersections at the boundaries. It is shown that the ''Epiquant'' analyzer ensures quantitative estimation of austenite grain size with relative error of 2-4 %.

Estimating Most Productive Scale Size in Data Envelopment Analysis with Integer Value Data

Science.gov (United States)

Dwi Sari, Yunita; Angria S, Layla; Efendi, Syahril; Zarlis, Muhammad

2018-01-01

The most productive scale size (MPSS) is a measurement that states how resources should be organized and utilized to achieve optimal results. The most productive scale size (MPSS) can be used as a benchmark for the success of an industry or company in producing goods or services. To estimate the most productive scale size (MPSS), each decision making unit (DMU) should pay attention the level of input-output efficiency, by data envelopment analysis (DEA) method decision making unit (DMU) can identify units used as references that can help to find the cause and solution from inefficiencies can optimize productivity that main advantage in managerial applications. Therefore, data envelopment analysis (DEA) is chosen to estimating most productive scale size (MPSS) that will focus on the input of integer value data with the CCR model and the BCC model. The purpose of this research is to find the best solution for estimating most productive scale size (MPSS) with input of integer value data in data envelopment analysis (DEA) method.

Estimation of the size of the female sex worker population in Rwanda using three different methods.

Science.gov (United States)

Mutagoma, Mwumvaneza; Kayitesi, Catherine; Gwiza, Aimé; Ruton, Hinda; Koleros, Andrew; Gupta, Neil; Balisanga, Helene; Riedel, David J; Nsanzimana, Sabin

2015-10-01

HIV prevalence is disproportionately high among female sex workers compared to the general population. Many African countries lack useful data on the size of female sex worker populations to inform national HIV programmes. A female sex worker size estimation exercise using three different venue-based methodologies was conducted among female sex workers in all provinces of Rwanda in August 2010. The female sex worker national population size was estimated using capture-recapture and enumeration methods, and the multiplier method was used to estimate the size of the female sex worker population in Kigali. A structured questionnaire was also used to supplement the data. The estimated number of female sex workers by the capture-recapture method was 3205 (95% confidence interval: 2998-3412). The female sex worker size was estimated at 3348 using the enumeration method. In Kigali, the female sex worker size was estimated at 2253 (95% confidence interval: 1916-2524) using the multiplier method. Nearly 80% of all female sex workers in Rwanda were found to be based in the capital, Kigali. This study provided a first-time estimate of the female sex worker population size in Rwanda using capture-recapture, enumeration, and multiplier methods. The capture-recapture and enumeration methods provided similar estimates of female sex worker in Rwanda. Combination of such size estimation methods is feasible and productive in low-resource settings and should be considered vital to inform national HIV programmes. © The Author(s) 2015.

Marketing and SMEs: Can an Organization of Any Size Use Marketing Plans?

OpenAIRE

Marjanova Jovanov, Tamara

2012-01-01

This paper is provoked from the ongoing condition of under – or misuse of marketing in SME, regarding the poor understanding of the benefits of marketing planning and the fact that marketing is often seen as a function of the business, rather than as its guiding philosophy. The research does not state that business success is not impossible in the absence of marketing planning, but it does argue that marketing plans can effectively and efficiently be used in SMEs as well as in ...

Monte Carlo-based tail exponent estimator

Science.gov (United States)

Barunik, Jozef; Vacha, Lukas

2010-11-01

In this paper we propose a new approach to estimation of the tail exponent in financial stock markets. We begin the study with the finite sample behavior of the Hill estimator under α-stable distributions. Using large Monte Carlo simulations, we show that the Hill estimator overestimates the true tail exponent and can hardly be used on samples with small length. Utilizing our results, we introduce a Monte Carlo-based method of estimation for the tail exponent. Our proposed method is not sensitive to the choice of tail size and works well also on small data samples. The new estimator also gives unbiased results with symmetrical confidence intervals. Finally, we demonstrate the power of our estimator on the international world stock market indices. On the two separate periods of 2002-2005 and 2006-2009, we estimate the tail exponent.

High-temperature gas reactor (HTGR) market assessment, synthetic fuels analysis

International Nuclear Information System (INIS)

1980-08-01

This study is an update of assessments made in TRW's October 1979 assessment of overall high-temperature gas-cooled reactor (HTGR) markets in the future synfuels industry (1985 to 2020). Three additional synfuels processes were assessed. Revised synfuel production forecasts were used. General environmental impacts were assessed. Additional market barriers, such as labor and materials, were researched. Market share estimates were used to consider the percent of markets applicable to the reference HTGR size plant. Eleven HTGR plants under nominal conditions and two under pessimistic assumptions are estimated for selection by 2020. No new HTGR markets were identified in the three additional synfuels processes studied. This reduction in TRW's earlier estimate is a result of later availability of HTGR's (commercial operation in 2008) and delayed build up in the total synfuels estimated markets. Also, a latest date for HTGR capture of a synfuels market could not be established because total markets continue to grow through 2020. If the nominal HTGR synfuels market is realized, just under one million tons of sulfur dioxide effluents and just over one million tons of nitrous oxide effluents will be avoided by 2020. Major barriers to a large synfuels industry discussed in this study include labor, materials, financing, siting, and licensing. Use of the HTGR intensifies these barriers

Estimation of Tooth Size Discrepancies among Different Malocclusion Groups.

Science.gov (United States)

Hasija, Narender; Bala, Madhu; Goyal, Virender

2014-05-01

Regards and Tribute: Late Dr Narender Hasija was a mentor and visionary in the light of knowledge and experience. We pay our regards with deepest gratitude to the departed soul to rest in peace. Bolton's ratios help in estimating overbite, overjet relationships, the effects of contemplated extractions on posterior occlusion, incisor relationships and identification of occlusal misfit produced by tooth size discrepancies. To determine any difference in tooth size discrepancy in anterior as well as overall ratio in different malocclusions and comparison with Bolton's study. After measuring the teeth on all 100 patients, Bolton's analysis was performed. Results were compared with Bolton's means and standard deviations. The results were also subjected to statistical analysis. Results show that the mean and standard deviations of ideal occlusion cases are comparable with those Bolton but, when the mean and standard deviation of malocclusion groups are compared with those of Bolton, the values of standard deviation are higher, though the mean is comparable. How to cite this article: Hasija N, Bala M, Goyal V. Estimation of Tooth Size Discrepancies among Different Malocclusion Groups. Int J Clin Pediatr Dent 2014;7(2):82-85.

Estimating population sizes for elusive animals: the forest elephants of Kakum National Park, Ghana.

Science.gov (United States)

Eggert, L S; Eggert, J A; Woodruff, D S

2003-06-01

African forest elephants are difficult to observe in the dense vegetation, and previous studies have relied upon indirect methods to estimate population sizes. Using multilocus genotyping of noninvasively collected samples, we performed a genetic survey of the forest elephant population at Kakum National Park, Ghana. We estimated population size, sex ratio and genetic variability from our data, then combined this information with field observations to divide the population into age groups. Our population size estimate was very close to that obtained using dung counts, the most commonly used indirect method of estimating the population sizes of forest elephant populations. As their habitat is fragmented by expanding human populations, management will be increasingly important to the persistence of forest elephant populations. The data that can be obtained from noninvasively collected samples will help managers plan for the conservation of this keystone species.

Estimating zonal electricity supply curves in transmission-constrained electricity markets

International Nuclear Information System (INIS)

Sahraei-Ardakani, Mostafa; Blumsack, Seth; Kleit, Andrew

2015-01-01

Many important electricity policy initiatives would directly affect the operation of electric power networks. This paper develops a method for estimating short-run zonal supply curves in transmission-constrained electricity markets that can be implemented quickly by policy analysts with training in statistical methods and with publicly available data. Our model enables analysis of distributional impacts of policies affecting operation of electric power grid. The method uses fuel prices and zonal electric loads to determine piecewise supply curves, identifying zonal electricity price and marginal fuel. We illustrate our methodology by estimating zonal impacts of Pennsylvania's Act 129, an energy efficiency and conservation policy. For most utilities in Pennsylvania, Act 129 would reduce the influence of natural gas on electricity price formation and increase the influence of coal. The total resulted savings would be around 267 million dollars, 82 percent of which would be enjoyed by the customers in Pennsylvania. We also analyze the impacts of imposing a $35/ton tax on carbon dioxide emissions. Our results show that the policy would increase the average prices in PJM by 47–89 percent under different fuel price scenarios in the short run, and would lead to short-run interfuel substitution between natural gas and coal. - Highlights: • We develop a method to estimate of zonal supply curves in electricity markets. • The model estimates zonal electricity prices and zonal fuel utilization. • The model implicitly captures the average impacts of transmission constraints. • Using the method, we project supply curves for the seventeen utility zones of PJM. • We use the estimated supply curves to study the impacts of Pennsylvania's Act 129 and a carbon tax of $35 per ton

Testing Black Market vs. Official PPP: A Pooled Mean Group Estimation Approach

OpenAIRE

Goswami, Gour Gobinda; Hossain, Mohammad Zariab

2013-01-01

Testing purchasing power parity (PPP) using black market exchange rate data has gained popularity in recent times. It is claimed that black market exchange rate data more often support the PPP than the official exchange rate data. In this study, to assess both the long run stability of exchange rate and the short run dynamics, we employ Pooled Mean Group (PMG) Estimation developed by Pesaran et al. (1999) on eight groups of countries based on different criteria. Using the famous Reinhart and ...

Estimation of sample size and testing power (Part 3).

Science.gov (United States)

Hu, Liang-ping; Bao, Xiao-lei; Guan, Xue; Zhou, Shi-guo

2011-12-01

This article introduces the definition and sample size estimation of three special tests (namely, non-inferiority test, equivalence test and superiority test) for qualitative data with the design of one factor with two levels having a binary response variable. Non-inferiority test refers to the research design of which the objective is to verify that the efficacy of the experimental drug is not clinically inferior to that of the positive control drug. Equivalence test refers to the research design of which the objective is to verify that the experimental drug and the control drug have clinically equivalent efficacy. Superiority test refers to the research design of which the objective is to verify that the efficacy of the experimental drug is clinically superior to that of the control drug. By specific examples, this article introduces formulas of sample size estimation for the three special tests, and their SAS realization in detail.

Gas marketing: Does size equal survival?

International Nuclear Information System (INIS)

Katz, M.G.

1996-01-01

The thought is enough to make many homeowners cringe: competing natural gas marketers calling them at home in the evening, pushing their brands and services much like AT and T, MCI and Sprint hawk long-distance telephone service today. Another thought is enough to make many gas marketers cringe: a half-dozen or fewer giant mega-marketers selling virtually all the natural gas in the US, and they and their company are not among them. Yet both thoughts are likely to become realities, say many in the natural gas industry. If so, each would represent an intriguing turn of events for the newest segment of the industry, one that barely existed 10 or 15 years ago. The paper discusses the recent history of the gas marketing sector, the changes taking place in the industry, and the biggest problem--the lack of a uniform electronic standard or bulletin board system for dispatching, nominating, and monitoring gas purchase as they move across the country

Coopetition Effect Determinants: Competitor’s Size, Geographical Scope, Market and Technological Positions

Directory of Open Access Journals (Sweden)

Cygler Joanna

2015-12-01

Full Text Available Background and Goal: The article is aimed at conducting an empirical analysis of the value and significance of coopetitors’ attributes thanks to which coopetition, which is a combination of cooperation and competition between competitors, generates a substantial corporate profit. Four major competitors’ attributes have been analysed: its size, geographical scope, market and technological position. The research also includes the Porter’s value chain.

Short Communication Estimation of size at first maturity in two South ...

African Journals Online (AJOL)

Short Communication Estimation of size at first maturity in two South African coral species. ... African Journal of Marine Science ... PH Montoya-Maya, AHH Macdonald, MH Schleyer ... to differentiate juveniles from adult sizes of corals, an important factor for assessing the condition of scleractinian communities in reefs. Here ...

THE INFLUENCE OF CONDITIONS OF THE STOCK MARKET AND MONETARY POLICY ON THE BEHAVIOROF RISK INDICATORS SIZE, BOOK-TO-MARKET RATIO AND MOMENTUM, ON THE BRAZILIAN STOCK MARKET

Directory of Open Access Journals (Sweden)

Adriano Mussa

2011-04-01

Full Text Available Last years, empirical tests of APT (Arbitrage Pricing Theory models have been intensified on the national and international literature, mainly using firm´s characteristics to construct risk factors in addition to the market beta. The Fama-French 3-factors model and the Carhart 4-factors model are two samples intensively tested of this type of models, with evidences of relative success. On this scenario, it is important to deepen the studies of the factor´s behavior that compose these models. Following the way of international researches, the purpose of this article is to investigate the behavior of the factors: size, book-to-market ratio and momentum, on the Brazilian stock market, in conditions of i up and down markets ii expansive and restrictive monetary policy. The sample was composed by all stocks listed on BOVESPA, from June of 1995 to June of 2007. The methodology was the same used by Fama & French (1993 to construct the portfolios and risk factors. The results indicated that the stock market and monetary environment influence the regularities in the factor´s behavior, on the Brazilian Stock markets.

Estimated spatial requirements of the medium- to large-sized ...

African Journals Online (AJOL)

Conservation planning in the Cape Floristic Region (CFR) of South Africa, a recognised world plant diversity hotspot, required information on the estimated spatial requirements of selected medium- to large-sized mammals within each of 102 Broad Habitat Units (BHUs) delineated according to key biophysical parameters.

Estimation of particle size distribution of nanoparticles from electrical ...

Indian Academy of Sciences (India)

... blockade (CB) phenomena of electrical conduction through atiny nanoparticle. Considering the ZnO nanocomposites to be spherical, Coulomb-blockade model of quantum dot isapplied here. The size distribution of particle is estimated from that model and compared with the results obtainedfrom AFM and XRD analyses.

Gluttonous predators: how to estimate prey size when there are too many prey

Directory of Open Access Journals (Sweden)

MS. Araújo

Full Text Available Prey size is an important factor in food consumption. In studies of feeding ecology, prey items are usually measured individually using calipers or ocular micrometers. Among amphibians and reptiles, there are species that feed on large numbers of small prey items (e.g. ants, termites. This high intake makes it difficult to estimate prey size consumed by these animals. We addressed this problem by developing and evaluating a procedure for subsampling the stomach contents of such predators in order to estimate prey size. Specifically, we developed a protocol based on a bootstrap procedure to obtain a subsample with a precision error of at the most 5%, with a confidence level of at least 95%. This guideline should reduce the sampling effort and facilitate future studies on the feeding habits of amphibians and reptiles, and also provide a means of obtaining precise estimates of prey size.

A comparison study of size-specific dose estimate calculation methods

Energy Technology Data Exchange (ETDEWEB)

Parikh, Roshni A. [Rainbow Babies and Children' s Hospital, University Hospitals Cleveland Medical Center, Case Western Reserve University School of Medicine, Department of Radiology, Cleveland, OH (United States); University of Michigan Health System, Department of Radiology, Ann Arbor, MI (United States); Wien, Michael A.; Jordan, David W.; Ciancibello, Leslie; Berlin, Sheila C. [Rainbow Babies and Children' s Hospital, University Hospitals Cleveland Medical Center, Case Western Reserve University School of Medicine, Department of Radiology, Cleveland, OH (United States); Novak, Ronald D. [Rainbow Babies and Children' s Hospital, University Hospitals Cleveland Medical Center, Case Western Reserve University School of Medicine, Department of Radiology, Cleveland, OH (United States); Rebecca D. Considine Research Institute, Children' s Hospital Medical Center of Akron, Center for Mitochondrial Medicine Research, Akron, OH (United States); Klahr, Paul [CT Clinical Science, Philips Healthcare, Highland Heights, OH (United States); Soriano, Stephanie [Rainbow Babies and Children' s Hospital, University Hospitals Cleveland Medical Center, Case Western Reserve University School of Medicine, Department of Radiology, Cleveland, OH (United States); University of Washington, Department of Radiology, Seattle, WA (United States)

2018-01-15

The size-specific dose estimate (SSDE) has emerged as an improved metric for use by medical physicists and radiologists for estimating individual patient dose. Several methods of calculating SSDE have been described, ranging from patient thickness or attenuation-based (automated and manual) measurements to weight-based techniques. To compare the accuracy of thickness vs. weight measurement of body size to allow for the calculation of the size-specific dose estimate (SSDE) in pediatric body CT. We retrospectively identified 109 pediatric body CT examinations for SSDE calculation. We examined two automated methods measuring a series of level-specific diameters of the patient's body: method A used the effective diameter and method B used the water-equivalent diameter. Two manual methods measured patient diameter at two predetermined levels: the superior endplate of L2, where body width is typically most thin, and the superior femoral head or iliac crest (for scans that did not include the pelvis), where body width is typically most thick; method C averaged lateral measurements at these two levels from the CT projection scan, and method D averaged lateral and anteroposterior measurements at the same two levels from the axial CT images. Finally, we used body weight to characterize patient size, method E, and compared this with the various other measurement methods. Methods were compared across the entire population as well as by subgroup based on body width. Concordance correlation (ρ{sub c}) between each of the SSDE calculation methods (methods A-E) was greater than 0.92 across the entire population, although the range was wider when analyzed by subgroup (0.42-0.99). When we compared each SSDE measurement method with CTDI{sub vol,} there was poor correlation, ρ{sub c}<0.77, with percentage differences between 20.8% and 51.0%. Automated computer algorithms are accurate and efficient in the calculation of SSDE. Manual methods based on patient thickness provide

Sample size estimation and sampling techniques for selecting a representative sample

Directory of Open Access Journals (Sweden)

Aamir Omair

2014-01-01

Full Text Available Introduction: The purpose of this article is to provide a general understanding of the concepts of sampling as applied to health-related research. Sample Size Estimation: It is important to select a representative sample in quantitative research in order to be able to generalize the results to the target population. The sample should be of the required sample size and must be selected using an appropriate probability sampling technique. There are many hidden biases which can adversely affect the outcome of the study. Important factors to consider for estimating the sample size include the size of the study population, confidence level, expected proportion of the outcome variable (for categorical variables/standard deviation of the outcome variable (for numerical variables, and the required precision (margin of accuracy from the study. The more the precision required, the greater is the required sample size. Sampling Techniques: The probability sampling techniques applied for health related research include simple random sampling, systematic random sampling, stratified random sampling, cluster sampling, and multistage sampling. These are more recommended than the nonprobability sampling techniques, because the results of the study can be generalized to the target population.

Effects of sample size on estimates of population growth rates calculated with matrix models.

Directory of Open Access Journals (Sweden)

Ian J Fiske

Full Text Available BACKGROUND: Matrix models are widely used to study the dynamics and demography of populations. An important but overlooked issue is how the number of individuals sampled influences estimates of the population growth rate (lambda calculated with matrix models. Even unbiased estimates of vital rates do not ensure unbiased estimates of lambda-Jensen's Inequality implies that even when the estimates of the vital rates are accurate, small sample sizes lead to biased estimates of lambda due to increased sampling variance. We investigated if sampling variability and the distribution of sampling effort among size classes lead to biases in estimates of lambda. METHODOLOGY/PRINCIPAL FINDINGS: Using data from a long-term field study of plant demography, we simulated the effects of sampling variance by drawing vital rates and calculating lambda for increasingly larger populations drawn from a total population of 3842 plants. We then compared these estimates of lambda with those based on the entire population and calculated the resulting bias. Finally, we conducted a review of the literature to determine the sample sizes typically used when parameterizing matrix models used to study plant demography. CONCLUSIONS/SIGNIFICANCE: We found significant bias at small sample sizes when survival was low (survival = 0.5, and that sampling with a more-realistic inverse J-shaped population structure exacerbated this bias. However our simulations also demonstrate that these biases rapidly become negligible with increasing sample sizes or as survival increases. For many of the sample sizes used in demographic studies, matrix models are probably robust to the biases resulting from sampling variance of vital rates. However, this conclusion may depend on the structure of populations or the distribution of sampling effort in ways that are unexplored. We suggest more intensive sampling of populations when individual survival is low and greater sampling of stages with high

Effects of sample size on estimates of population growth rates calculated with matrix models.

Science.gov (United States)

Fiske, Ian J; Bruna, Emilio M; Bolker, Benjamin M

2008-08-28

Matrix models are widely used to study the dynamics and demography of populations. An important but overlooked issue is how the number of individuals sampled influences estimates of the population growth rate (lambda) calculated with matrix models. Even unbiased estimates of vital rates do not ensure unbiased estimates of lambda-Jensen's Inequality implies that even when the estimates of the vital rates are accurate, small sample sizes lead to biased estimates of lambda due to increased sampling variance. We investigated if sampling variability and the distribution of sampling effort among size classes lead to biases in estimates of lambda. Using data from a long-term field study of plant demography, we simulated the effects of sampling variance by drawing vital rates and calculating lambda for increasingly larger populations drawn from a total population of 3842 plants. We then compared these estimates of lambda with those based on the entire population and calculated the resulting bias. Finally, we conducted a review of the literature to determine the sample sizes typically used when parameterizing matrix models used to study plant demography. We found significant bias at small sample sizes when survival was low (survival = 0.5), and that sampling with a more-realistic inverse J-shaped population structure exacerbated this bias. However our simulations also demonstrate that these biases rapidly become negligible with increasing sample sizes or as survival increases. For many of the sample sizes used in demographic studies, matrix models are probably robust to the biases resulting from sampling variance of vital rates. However, this conclusion may depend on the structure of populations or the distribution of sampling effort in ways that are unexplored. We suggest more intensive sampling of populations when individual survival is low and greater sampling of stages with high elasticities.

Sampling strategies for estimating brook trout effective population size

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Andrew R. Whiteley; Jason A. Coombs; Mark Hudy; Zachary Robinson; Keith H. Nislow; Benjamin H. Letcher

2012-01-01

The influence of sampling strategy on estimates of effective population size (Ne) from single-sample genetic methods has not been rigorously examined, though these methods are increasingly used. For headwater salmonids, spatially close kin association among age-0 individuals suggests that sampling strategy (number of individuals and location from...

Market structure and competition in the healthcare industry : Results from a transition economy.

Science.gov (United States)

Lábaj, Martin; Silanič, Peter; Weiss, Christoph; Yontcheva, Biliana

2018-02-14

The present paper provides first empirical evidence on the relationship between market size and the number of firms in the healthcare industry for a transition economy. We estimate market-size thresholds required to support different numbers of suppliers (firms) for three occupations in the healthcare industry in a large number of distinct geographic markets in Slovakia, taking into account the spatial interaction between local markets. The empirical analysis is carried out for three time periods (1995, 2001 and 2010) which characterise different stages of the transition process. Our results suggest that the relationship between market size and the number of firms differs both across industries and across periods. In particular, we find that pharmacies, as the only completely liberalised market in our dataset, experience the largest change in competitive behaviour during the transition process. Furthermore, we find evidence for correlation in entry decisions across administrative borders, suggesting that future market analysis should aim to capture these regional effects.

Volatility measurement with directional change in Chinese stock market: Statistical property and investment strategy

Science.gov (United States)

Ma, Junjun; Xiong, Xiong; He, Feng; Zhang, Wei

2017-04-01

The stock price fluctuation is studied in this paper with intrinsic time perspective. The event, directional change (DC) or overshoot, are considered as time scale of price time series. With this directional change law, its corresponding statistical properties and parameter estimation is tested in Chinese stock market. Furthermore, a directional change trading strategy is proposed for invest in the market portfolio in Chinese stock market, and both in-sample and out-of-sample performance are compared among the different method of model parameter estimation. We conclude that DC method can capture important fluctuations in Chinese stock market and gain profit due to the statistical property that average upturn overshoot size is bigger than average downturn directional change size. The optimal parameter of DC method is not fixed and we obtained 1.8% annual excess return with this DC-based trading strategy.

Market Size and Innovation: Effects of Medicare Part D on Pharmaceutical Research and Development.

Science.gov (United States)

Blume-Kohout, Margaret E; Sood, Neeraj

2013-01-01

Recent evidence suggests that Medicare Part D increased prescription drug use among seniors, and increased pharmaceutical firms' revenues from sales. Previous studies also indicate that increases in market size induce pharmaceutical innovation. This paper assesses the impact of the Medicare Part D legislation on pharmaceutical research and development (R&D), using time-series data on the number of drugs entering preclinical and clinical development by therapeutic class and phase. We find that the passage and implementation of Medicare Part D is associated with significant increases in pharmaceutical R&D for therapeutic classes with higher Medicare market share.

Bound on the estimation grid size for sparse reconstruction in direction of arrival estimation

NARCIS (Netherlands)

Coutiño Minguez, M.A.; Pribic, R; Leus, G.J.T.

2016-01-01

A bound for sparse reconstruction involving both the signal-to-noise ratio (SNR) and the estimation grid size is presented. The bound is illustrated for the case of a uniform linear array (ULA). By reducing the number of possible sparse vectors present in the feasible set of a constrained ℓ1-norm

Reliability of fish size estimates obtained from multibeam imaging sonar

Science.gov (United States)

Hightower, Joseph E.; Magowan, Kevin J.; Brown, Lori M.; Fox, Dewayne A.

2013-01-01

Multibeam imaging sonars have considerable potential for use in fisheries surveys because the video-like images are easy to interpret, and they contain information about fish size, shape, and swimming behavior, as well as characteristics of occupied habitats. We examined images obtained using a dual-frequency identification sonar (DIDSON) multibeam sonar for Atlantic sturgeon Acipenser oxyrinchus oxyrinchus, striped bass Morone saxatilis, white perch M. americana, and channel catfish Ictalurus punctatus of known size (20–141 cm) to determine the reliability of length estimates. For ranges up to 11 m, percent measurement error (sonar estimate – total length)/total length × 100 varied by species but was not related to the fish's range or aspect angle (orientation relative to the sonar beam). Least-square mean percent error was significantly different from 0.0 for Atlantic sturgeon (x̄  =  −8.34, SE  =  2.39) and white perch (x̄  = 14.48, SE  =  3.99) but not striped bass (x̄  =  3.71, SE  =  2.58) or channel catfish (x̄  = 3.97, SE  =  5.16). Underestimating lengths of Atlantic sturgeon may be due to difficulty in detecting the snout or the longer dorsal lobe of the heterocercal tail. White perch was the smallest species tested, and it had the largest percent measurement errors (both positive and negative) and the lowest percentage of images classified as good or acceptable. Automated length estimates for the four species using Echoview software varied with position in the view-field. Estimates tended to be low at more extreme azimuthal angles (fish's angle off-axis within the view-field), but mean and maximum estimates were highly correlated with total length. Software estimates also were biased by fish images partially outside the view-field and when acoustic crosstalk occurred (when a fish perpendicular to the sonar and at relatively close range is detected in the side lobes of adjacent beams). These sources of

Size, Book-to-Market Ratio and Relativity of Accounting Information Value: Empirical Research on the Chinese Listed Company

Science.gov (United States)

Yu, Jing; Cheng, Siwei; Xu, Bin

Recently there are many literatures studying the effect of factors such as size or book-market ratio on fluctuation of accounting earnings, stock price or earnings respectively, but so far their affection on accounting information value relativity has been scarcely addressed. This paper presents the detail analyses of their effect of the two factors to the relativity of accounting information value respectively by taking Shanghai and Shenzhen stock markets as sample. And the analyses supports the following two hypotheses, (1) The relativity of accounting information value of big size corporation is more than that of small size corporation. (2) The relativity of accounting information value of low B/M ratio corporation is more than that of low B/M ratio corporation.

Correlates of in-store promotions for beer: differential effects of market and product characteristics.

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Bray, Jeremy W; Loomis, Brett; Engelen, Mark

2007-03-01

We estimated the strength and direction of the association between product characteristics (beer type, package size, and brand name) and market-area socioeconomic characteristics, and promoted sales of beer in grocery stores. Supermarket scanner data from 64 market areas across the United States over 5 years were used to estimate regression models of the share of beer sales that are promoted, controlling for beer price, packaging, and type; and for market-level age, race/ethnicity, income, unemployment rate, and percentage of the population living in an alcohol control state. Large-volume units, such as 144-oz and 288-oz packages, are more likely to be promoted than smaller package sizes. Malt-liquor beverages are less likely to be promoted than non-malt-liquor beverages. Age, race/ethnicity, income, and geographic location of the market area are not significantly related to promoted beer sales. Marketing research has shown that in-store merchandising and promotions can substantially increase beer sales and that purchasing large package sizes may increase total consumption. Our results suggest that high levels of promoted sales for large-volume beer packages may result in increased beer consumption.

EXPLAINING CORPORATE STRUCTURE:THE MD MATRIX, PRODUCT DIFFERENTIATION AND SIZE OF MARKET

OpenAIRE

Alessandro Sembenelli; Laura Rondi; Stephen W. Davies

1995-01-01

Conventional explanations of diversification and multinationality both point to the existence of intangible assets as a driving force. Using a new database of leading EU firms in 100 NACE 3-digit industries, we devise a classificatory scheme which allows us to analyze multinationality and diversification jointly. We find that product differentiation and home market primary industry size constraints impact differently on different types of diversified firms. For instance, it appears that the c...

Towards the Estimation of an Efficient Benchmark Portfolio: The Case of Croatian Emerging Market

Directory of Open Access Journals (Sweden)

Dolinar Denis

2017-04-01

Full Text Available The fact that cap-weighted indices provide an inefficient risk-return trade-off is well known today. Various research approaches evolved suggesting alternative to cap-weighting in an effort to come up with a more efficient market index benchmark. In this paper we aim to use such an approach and focus on the Croatian capital market. We apply statistical shrinkage method suggested by Ledoit and Wolf (2004 to estimate the covariance matrix and follow the work of Amenc et al. (2011 to obtain estimates of expected returns that rely on risk-return trade-off. Empirical findings for the proposed portfolio optimization include out-of-sample and robustness testing. This way we compare the performance of the capital-weighted benchmark to the alternative and ensure that consistency is achieved in different volatility environments. Research findings do not seem to support relevant research results for the developed markets but rather complement earlier research (Zoričić et al., 2014.

Formative evaluation of a mobile liquid portion size estimation interface for people with varying literacy skills.

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Chaudry, Beenish Moalla; Connelly, Kay; Siek, Katie A; Welch, Janet L

2013-12-01

Chronically ill people, especially those with low literacy skills, often have difficulty estimating portion sizes of liquids to help them stay within their recommended fluid limits. There is a plethora of mobile applications that can help people monitor their nutritional intake but unfortunately these applications require the user to have high literacy and numeracy skills for portion size recording. In this paper, we present two studies in which the low- and the high-fidelity versions of a portion size estimation interface, designed using the cognitive strategies adults employ for portion size estimation during diet recall studies, was evaluated by a chronically ill population with varying literacy skills. The low fidelity interface was evaluated by ten patients who were all able to accurately estimate portion sizes of various liquids with the interface. Eighteen participants did an in situ evaluation of the high-fidelity version incorporated in a diet and fluid monitoring mobile application for 6 weeks. Although the accuracy of the estimation cannot be confirmed in the second study but the participants who actively interacted with the interface showed better health outcomes by the end of the study. Based on these findings, we provide recommendations for designing the next iteration of an accurate and low literacy-accessible liquid portion size estimation mobile interface.

Hospital prices and market structure in the hospital and insurance industries.

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Moriya, Asako S; Vogt, William B; Gaynor, Martin

2010-10-01

There has been substantial consolidation among health insurers and hospitals, recently, raising questions about the effects of this consolidation on the exercise of market power. We analyze the relationship between insurer and hospital market concentration and the prices of hospital services. We use a national US dataset containing transaction prices for health care services for over 11 million privately insured Americans. Using three years of panel data, we estimate how insurer and hospital market concentration are related to hospital prices, while controlling for unobserved market effects. We find that increases in insurance market concentration are significantly associated with decreases in hospital prices, whereas increases in hospital concentration are non-significantly associated with increases in prices. A hypothetical merger between two of five equally sized insurers is estimated to decrease hospital prices by 6.7%.

Estimation of a simple agent-based model of financial markets: An application to Australian stock and foreign exchange data

Science.gov (United States)

Alfarano, Simone; Lux, Thomas; Wagner, Friedrich

2006-10-01

Following Alfarano et al. [Estimation of agent-based models: the case of an asymmetric herding model, Comput. Econ. 26 (2005) 19-49; Excess volatility and herding in an artificial financial market: analytical approach and estimation, in: W. Franz, H. Ramser, M. Stadler (Eds.), Funktionsfähigkeit und Stabilität von Finanzmärkten, Mohr Siebeck, Tübingen, 2005, pp. 241-254], we consider a simple agent-based model of a highly stylized financial market. The model takes Kirman's ant process [A. Kirman, Epidemics of opinion and speculative bubbles in financial markets, in: M.P. Taylor (Ed.), Money and Financial Markets, Blackwell, Cambridge, 1991, pp. 354-368; A. Kirman, Ants, rationality, and recruitment, Q. J. Econ. 108 (1993) 137-156] of mimetic contagion as its starting point, but allows for asymmetry in the attractiveness of both groups. Embedding the contagion process into a standard asset-pricing framework, and identifying the abstract groups of the herding model as chartists and fundamentalist traders, a market with periodic bubbles and bursts is obtained. Taking stock of the availability of a closed-form solution for the stationary distribution of returns for this model, we can estimate its parameters via maximum likelihood. Expanding our earlier work, this paper presents pertinent estimates for the Australian dollar/US dollar exchange rate and the Australian stock market index. As it turns out, our model indicates dominance of fundamentalist behavior in both the stock and foreign exchange market.

Food photography II: use of food photographs for estimating portion size and the nutrient content of meals.

Science.gov (United States)

Nelson, M; Atkinson, M; Darbyshire, S

1996-07-01

The aim of the present study was to determine the errors in the conceptualization of portion size using photographs. Male and female volunteers aged 18-90 years (n 136) from a wide variety of social and occupational backgrounds completed 602 assessments of portion size in relation to food photographs. Subjects served themselves between four and six foods at one meal (breakfast, lunch or dinner). Portion sizes were weighed by the investigators at the time of serving, and any waste was weighed at the end of the meal. Within 5 min of the end of the meal, subjects were shown photographs depicting each of the foods just consumed. For each food there were eight photographs showing portion sizes in equal increments from the 5th to the 95th centile of the distribution of portion weights observed in The Dietary and Nutritional Survey of British Adults (Gregory et al. 1990). Subjects were asked to indicate on a visual analogue scale the size of the portion consumed in relation to the eight photographs. The nutrient contents of meals were estimated from food composition tables. There were large variations in the estimation of portion sizes from photographs. Butter and margarine portion sizes tended to be substantially overestimated. In general, small portion sizes tended to be overestimated, and large portion sizes underestimated. Older subjects overestimated portion size more often than younger subjects. Excluding butter and margarine, the nutrient content of meals based on estimated portion sizes was on average within +/- 7% of the nutrient content based on the amounts consumed, except for vitamin C (21% overestimate), and for subjects over 65 years (15-20% overestimate for energy and fat). In subjects whose BMI was less than 25 kg/m2, the energy and fat contents of meals calculated from food composition tables and based on estimated portion size (excluding butter and margarine) were 5-10% greater than the nutrient content calculated using actual portion size, but for those

Why liquid displacement methods are sometimes wrong in estimating the pore-size distribution

NARCIS (Netherlands)

Gijsbertsen-Abrahamse, A.J.; Boom, R.M.; Padt, van der A.

2004-01-01

The liquid displacement method is a commonly used method to determine the pore size distribution of micro- and ultrafiltration membranes. One of the assumptions for the calculation of the pore sizes is that the pores are parallel and thus are not interconnected. To show that the estimated pore size

ON ESTIMATION AND HYPOTHESIS TESTING OF THE GRAIN SIZE DISTRIBUTION BY THE SALTYKOV METHOD

Directory of Open Access Journals (Sweden)

Yuri Gulbin

2011-05-01

Full Text Available The paper considers the problem of validity of unfolding the grain size distribution with the back-substitution method. Due to the ill-conditioned nature of unfolding matrices, it is necessary to evaluate the accuracy and precision of parameter estimation and to verify the possibility of expected grain size distribution testing on the basis of intersection size histogram data. In order to review these questions, the computer modeling was used to compare size distributions obtained stereologically with those possessed by three-dimensional model aggregates of grains with a specified shape and random size. Results of simulations are reported and ways of improving the conventional stereological techniques are suggested. It is shown that new improvements in estimating and testing procedures enable grain size distributions to be unfolded more efficiently.

Biomagnification and tissue distribution of perfluoroalkyl substances (PFASs) in market-size rainbow trout (Oncorhynchus mykiss).

Science.gov (United States)

Goeritz, Ina; Falk, Sandy; Stahl, Thorsten; Schäfers, Christoph; Schlechtriem, Christian

2013-09-01

The present study investigated the biomagnification potential as well as the substance and tissue-specific distribution of perfluoroalkyl substances (PFASs) in market-size rainbow trout (Oncorhynchus mykiss). Rainbow trout with an average body weight of 314 ± 21 g were exposed to perfluorobutane sulfonate (PFBS), perfluorohexane sulfonate (PFHxS), perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), and perfluorononanoic acid (PFNA) in the diet for 28 d. The accumulation phase was followed by a 28-d depuration phase, in which the test animals were fed with nonspiked trout feed. On days 0, 7, 14, 28, 31, 35, 42, and 56 of the present study, fish were sampled from the test basin for PFAS analysis. Biomagnification factors (BMFs) for all test compounds were determined based on a kinetic approach. Distribution factors were calculated for each test compound to illustrate the disposition of PFASs in rainbow trout after 28 d of exposure. Dietary exposure of market-size rainbow trout to PFASs did not result in biomagnification; BMF values were calculated as 0.42 for PFOS, >0.23 for PFNA, >0.18 for PFHxS, >0.04 for PFOA, and >0.02 for PFBS, which are below the biomagnification threshold of 1. Liver, blood, kidney, and skin were identified as the main target tissues for PFASs in market-size rainbow trout. Evidence was shown that despite relative low PFAS contamination, the edible parts of the fish (the fillet and skin) can significantly contribute to the whole-body burden. Copyright © 2013 SETAC.

[Calculating the optimum size of a hemodialysis unit based on infrastructure potential].

Science.gov (United States)

Avila-Palomares, Paula; López-Cervantes, Malaquías; Durán-Arenas, Luis

2010-01-01

To estimate the optimum size for hemodialysis units to maximize production given capital constraints. A national study in Mexico was conducted in 2009. Three possible methods for estimating a units optimum size were analyzed: hemodialysis services production under monopolistic market, under a perfect competitive market and production maximization given capital constraints. The third method was considered best based on the assumptions made in this paper; an optimal size unit should have 16 dialyzers (15 active and one back up dialyzer) and a purifier system able to supply all. It also requires one nephrologist, five nurses per shift, considering four shifts per day. Empirical evidence shows serious inefficiencies in the operation of units throughout the country. Most units fail to maximize production due to not fully utilizing equipment and personnel, particularly their water purifier potential which happens to be the most expensive asset for these units.

IMPACT OF LIQUIDITY AND SIZE PREMIUM ON EQUITY PRICE FORMATION IN SERBIA

OpenAIRE

Jelena Minović; Boško Živković

2012-01-01

The goal of this paper is to examine the impact of an overall market factor, the factor related to the firm size, the factor related to the ratio of book to market value of companies, and the factor of liquidity risk on expected asset returns in the Serbian market. For this market we estimated different factor models: Capital Asset Pricing Model (CAPM by Sharpe, 1964), Fama-French (FF) model (1992, 1993), Liquidity-augmented CAPM (LCAPM) by Liu (2006), and combination LCAPM with FF factors. W...

Accounting for One-Group Clustering in Effect-Size Estimation

Science.gov (United States)

Citkowicz, Martyna; Hedges, Larry V.

2013-01-01

In some instances, intentionally or not, study designs are such that there is clustering in one group but not in the other. This paper describes methods for computing effect size estimates and their variances when there is clustering in only one group and the analysis has not taken that clustering into account. The authors provide the effect size…

NDE errors and their propagation in sizing and growth estimates

International Nuclear Information System (INIS)

Horn, D.; Obrutsky, L.; Lakhan, R.

2009-01-01

The accuracy attributed to eddy current flaw sizing determines the amount of conservativism required in setting tube-plugging limits. Several sources of error contribute to the uncertainty of the measurements, and the way in which these errors propagate and interact affects the overall accuracy of the flaw size and flaw growth estimates. An example of this calculation is the determination of an upper limit on flaw growth over one operating period, based on the difference between two measurements. Signal-to-signal comparison involves a variety of human, instrumental, and environmental error sources; of these, some propagate additively and some multiplicatively. In a difference calculation, specific errors in the first measurement may be correlated with the corresponding errors in the second; others may be independent. Each of the error sources needs to be identified and quantified individually, as does its distribution in the field data. A mathematical framework for the propagation of the errors can then be used to assess the sensitivity of the overall uncertainty to each individual error component. This paper quantifies error sources affecting eddy current sizing estimates and presents analytical expressions developed for their effect on depth estimates. A simple case study is used to model the analysis process. For each error source, the distribution of the field data was assessed and propagated through the analytical expressions. While the sizing error obtained was consistent with earlier estimates and with deviations from ultrasonic depth measurements, the error on growth was calculated as significantly smaller than that obtained assuming uncorrelated errors. An interesting result of the sensitivity analysis in the present case study is the quantification of the error reduction available from post-measurement compensation of magnetite effects. With the absolute and difference error equations, variance-covariance matrices, and partial derivatives developed in

Market skewness risk and the cross section of stock returns

DEFF Research Database (Denmark)

Chang, B.Y.; Christoffersen, Peter; Jacobs, K.

2013-01-01

The cross section of stock returns has substantial exposure to risk captured by higher moments of market returns. We estimate these moments from daily Standard & Poor's 500 index option data. The resulting time series of factors are genuinely conditional and forward-looking. Stocks with high...... exposure to innovations in implied market skewness exhibit low returns on average. The results are robust to various permutations of the empirical setup. The market skewness risk premium is statistically and economically significant and cannot be explained by other common risk factors such as the market...... excess return or the size, book-to-market, momentum, and market volatility factors, or by firm characteristics....

Estimating attractiveness for abuse of a not-yet-marketed "abuse-deterrent" prescription opioid formulation.

Science.gov (United States)

Butler, Stephen F; Black, Ryan; Grimes Serrano, Jill M; Folensbee, Lesley; Chang, Alan; Katz, Nathaniel

2010-01-01

The present study builds on research to model abusers' perceptions of particular analgesics' attractiveness for abuse and extends these methods to derive an estimate of attractiveness for abuse of a not-yet-marketed abuse-deterrent formulation (ADF) of a prescription opioid (Remoxy), Pain Therapeutics, Inc., San Mateo, CA, and King Pharmaceuticals, Inc., Bristol, TN). In a previous study, the Opioid Attractiveness Technology Scaling (OATS) method identified, from a drug abuser's point of view, the particular features of a prescription opioid relevant to its attractiveness for recreational use. A second online sample rated the extent to which these features applied to particular products they had actually used/abused. These data were used to model the abusers' overall preference for prescription opioids they had used/abused. In the present study, this method was applied to a not-yet-marketed ADF using substance abuse counselors as proxies for prescription opioid abusers. Thirty-eight counselors were given materials describing the new ADF along with four known products. Thirty-two counselors demonstrated sufficient agreement with abusers' ratings of the overall attractiveness of these drugs. The overall model yielded a significant pseudo R(2) of 0.15 (P marketing estimates of attractiveness for abuse of not-yet-marketed ADFs.

Size estimates of nobel gas clusters by Rayleigh scattering experiments

Institute of Scientific and Technical Information of China (English)

Pinpin Zhu (朱频频); Guoquan Ni (倪国权); Zhizhan Xu (徐至展)

2003-01-01

Noble gases (argon, krypton, and xenon) are puffed into vacuum through a nozzle to produce clusters for studying laser-cluster interactions. Good estimates of the average size of the argon, krypton and xenon clusters are made by carrying out a series of Rayleigh scattering experiments. In the experiments, we have found that the scattered signal intensity varied greatly with the opening area of the pulsed valve. A new method is put forward to choose the appropriate scattered signal and measure the size of Kr cluster.

The Exempt Market in Canada: Empirics, Observations and Recommendations

Directory of Open Access Journals (Sweden)

Vijay Jog

2015-03-01

Full Text Available There is a massive and vital capital market at work in Canada — possibly bigger than rough estimates have so far suggested — and it is one for which several market regulators are preparing new rules. Yet the remarkable thing is how little we know about it. Data about the so-called exempt market are so lacking that were regulators in Ontario and the other provinces contemplating new exempt-market regulations to proceed, they would be creating policies based on anecdotal, incomplete and, potentially, incorrect evidence. Even estimating the size of the Canadian exempt market has been an inexact science, given the incomplete data, but we can estimate that it provides in excess of $100 billion in gross capital flow every year, and that amount continues to grow. While it may be natural to assume that the exempt market is used primarily by small and medium-sized enterprises, it seems it is primarily used by the financial services industry. These institutions appear to rely on the exempt market to raise potentially short-term debt capital relatively free of particularly burdensome information-disclosure requirements. Unfortunately, we are forced to rely here again on deductions based on limited evidence: So incomplete are the data about the exempt market that we lack even complete information on the type of issuers, investors and securities, or the volume and duration of the securities and the level of redemptions. The exempt market exists for important reasons: it is a way out of the regulatory conundrum, wherein the regulator’s mandate to protect investors, through significant requirements for information disclosure, can put too large a burden on certain issuers. That is why it is essential that any new regulations are developed using a thorough understanding of how it operates. Yet the reality is that it is impossible to evaluate how individual investors and small firms are using the exempt market, or their experience in it. This is

Estimation of the ancestral effective population sizes of African great apes under different selection regimes.

Science.gov (United States)

Schrago, Carlos G

2014-08-01

Reliable estimates of ancestral effective population sizes are necessary to unveil the population-level phenomena that shaped the phylogeny and molecular evolution of the African great apes. Although several methods have previously been applied to infer ancestral effective population sizes, an analysis of the influence of the selective regime on the estimates of ancestral demography has not been thoroughly conducted. In this study, three independent data sets under different selective regimes were used were composed to tackle this issue. The results showed that selection had a significant impact on the estimates of ancestral effective population sizes of the African great apes. The inference of the ancestral demography of African great apes was affected by the selection regime. The effects, however, were not homogeneous along the ancestral populations of great apes. The effective population size of the ancestor of humans and chimpanzees was more impacted by the selection regime when compared to the same parameter in the ancestor of humans, chimpanzees and gorillas. Because the selection regime influenced the estimates of ancestral effective population size, it is reasonable to assume that a portion of the discrepancy found in previous studies that inferred the ancestral effective population size may be attributable to the differential action of selection on the genes sampled.

Estimation of body-size traits by photogrammetry in large mammals to inform conservation.

Science.gov (United States)

Berger, Joel

2012-10-01

Photography, including remote imagery and camera traps, has contributed substantially to conservation. However, the potential to use photography to understand demography and inform policy is limited. To have practical value, remote assessments must be reasonably accurate and widely deployable. Prior efforts to develop noninvasive methods of estimating trait size have been motivated by a desire to answer evolutionary questions, measure physiological growth, or, in the case of illegal trade, assess economics of horn sizes; but rarely have such methods been directed at conservation. Here I demonstrate a simple, noninvasive photographic technique and address how knowledge of values of individual-specific metrics bears on conservation policy. I used 10 years of data on juvenile moose (Alces alces) to examine whether body size and probability of survival are positively correlated in cold climates. I investigated whether the presence of mothers improved juvenile survival. The posited latter relation is relevant to policy because harvest of adult females has been permitted in some Canadian and American jurisdictions under the assumption that probability of survival of young is independent of maternal presence. The accuracy of estimates of head sizes made from photographs exceeded 98%. The estimates revealed that overwinter juvenile survival had no relation to the juvenile's estimated mass (p < 0.64) and was more strongly associated with maternal presence (p < 0.02) than winter snow depth (p < 0.18). These findings highlight the effects on survival of a social dynamic (the mother-young association) rather than body size and suggest a change in harvest policy will increase survival. Furthermore, photographic imaging of growth of individual juvenile muskoxen (Ovibos moschatus) over 3 Arctic winters revealed annual variability in size, which supports the idea that noninvasive monitoring may allow one to detect how some environmental conditions ultimately affect body growth. �

Marginal cost and congestion in the Italian electricity market: An indirect estimation approach

International Nuclear Information System (INIS)

Bigerna, Simona; Andrea Bollino, Carlo; Polinori, Paolo

2015-01-01

In this paper we construct an indirect measure of the supply marginal cost function for the main generators from the observed bid data in the Italian electricity market in the period 2004–2007. We compute the residual demand function for each generator, taking explicitly into account the issue of transmission line congestion. This procedure allows recovering correct zonal Lerner index and the implied measure of the marginal cost function. We find evidence of a stable U-shaped marginal cost function for three main Italian generators, but a flat function for ENEL, the former national monopolist. The policy relevance of our approach lies in the possibility to offer some empirical knowledge of the marginal cost function of each generator to the regulator to design appropriate policy measures geared to the promotion of competitive market conditions. We propose a new market surveillance mechanism, which is based on the principle of sanctioning excessive deviations from the estimated measure of the marginal cost function presented in this work. -- Highlights: •We construct an indirect measure of the supply marginal cost function. •We compute the residual demand function taking into account transmission line congestion. •We find a general evidence of a stable U-shaped marginal cost function for Italian generators. •We find flat marginal cost function for the former national monopolist. •We use excessive deviations from estimated marginal cost function as a new market surveillance mechanism

Portfolio Value at Risk Estimate for Crude Oil Markets: A Multivariate Wavelet Denoising Approach

Directory of Open Access Journals (Sweden)

Kin Keung Lai

2012-04-01

Full Text Available In the increasingly globalized economy these days, the major crude oil markets worldwide are seeing higher level of integration, which results in higher level of dependency and transmission of risks among different markets. Thus the risk of the typical multi-asset crude oil portfolio is influenced by dynamic correlation among different assets, which has both normal and transient behaviors. This paper proposes a novel multivariate wavelet denoising based approach for estimating Portfolio Value at Risk (PVaR. The multivariate wavelet analysis is introduced to analyze the multi-scale behaviors of the correlation among different markets and the portfolio volatility behavior in the higher dimensional time scale domain. The heterogeneous data and noise behavior are addressed in the proposed multi-scale denoising based PVaR estimation algorithm, which also incorporatesthe mainstream time series to address other well known data features such as autocorrelation and volatility clustering. Empirical studies suggest that the proposed algorithm outperforms the benchmark ExponentialWeighted Moving Average (EWMA and DCC-GARCH model, in terms of conventional performance evaluation criteria for the model reliability.

Effects of social organization, trap arrangement and density, sampling scale, and population density on bias in population size estimation using some common mark-recapture estimators.

Directory of Open Access Journals (Sweden)

Manan Gupta

Full Text Available Mark-recapture estimators are commonly used for population size estimation, and typically yield unbiased estimates for most solitary species with low to moderate home range sizes. However, these methods assume independence of captures among individuals, an assumption that is clearly violated in social species that show fission-fusion dynamics, such as the Asian elephant. In the specific case of Asian elephants, doubts have been raised about the accuracy of population size estimates. More importantly, the potential problem for the use of mark-recapture methods posed by social organization in general has not been systematically addressed. We developed an individual-based simulation framework to systematically examine the potential effects of type of social organization, as well as other factors such as trap density and arrangement, spatial scale of sampling, and population density, on bias in population sizes estimated by POPAN, Robust Design, and Robust Design with detection heterogeneity. In the present study, we ran simulations with biological, demographic and ecological parameters relevant to Asian elephant populations, but the simulation framework is easily extended to address questions relevant to other social species. We collected capture history data from the simulations, and used those data to test for bias in population size estimation. Social organization significantly affected bias in most analyses, but the effect sizes were variable, depending on other factors. Social organization tended to introduce large bias when trap arrangement was uniform and sampling effort was low. POPAN clearly outperformed the two Robust Design models we tested, yielding close to zero bias if traps were arranged at random in the study area, and when population density and trap density were not too low. Social organization did not have a major effect on bias for these parameter combinations at which POPAN gave more or less unbiased population size estimates

Marketing to the Bottom of the Pyramid and subsistence markets – A research agenda

Directory of Open Access Journals (Sweden)

Avinash G. Mulky

2011-01-01

Full Text Available The concepts of Bottom of the Pyramid (BOP and subsistence markets have attracted substantial academic and managerial attention in recent years. The BOP thesis states that there are opportunities for multinational companies to achieve significant revenues and profitability by designing and implementing marketing programs aimed at people who occupy the lowest tier in the world’s economic pyramid. The number of people in this segment has been estimated to be between 2.7 billion and 4 billion. This paper reviews the academic literature on BOP and subsistence markets and identifies important issues related to marketing to these consumers. The review is based on journal articles that have appeared in peer-reviewed journals and on case studies published by reputed academic institutions. The literature review first identifies a number of business issues like size of BOP market, motivations for undertaking BOP initiatives, ethics and linkages. Then specific marketing issues related to the BOP segment such as consumer analysis, company analysis, collaborators, competition and context, segmentation and positioning and issues relating to marketing program design and implementation are analyzed. Based on this analysis, the paper develops a research agenda for future research on BOP and subsistence markets.

7 CFR 51.344 - Size.

Science.gov (United States)

2010-01-01

... the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE REGULATIONS AND STANDARDS UNDER THE AGRICULTURAL MARKETING ACT OF 1946... Standards for Grades of Apples for Processing Size § 51.344 Size. (a) The minimum and maximum sizes or range...

Size matters: Exploring the importance of vessel characteristics to inform estimates of shipping emissions

International Nuclear Information System (INIS)

Walsh, Conor; Bows, Alice

2012-01-01

Highlights: ► Ship emission baselines can be used to inform studies but require prior knowledge. ► Region specific conditions alter average shipping emission factors. ► Region specific conditions are clearer when individual callings are examined. ► Relationship between ship size and emissions frustrates estimating mean emissions. -- Abstract: The decarbonisation agenda is placing increasing pressure on retailers to directly and indirectly influence greenhouse gas emissions associated with full supply chains. Transportation by sea is an important and significant element of these supply chains, yet the emissions associated with shipping, particularly international shipping, are often poorly accounted for. The magnitude of emissions embodied in a product is directly related to the distances involved in globalised product chains, where shipping can represent the most emission intensive stage per tonne of goods transported. Specifically, limited choice of ship type and size within assessment tools negates a fair estimate of product chain emissions. To address this, the correlation between ship emissions and size is quantified for a sample of United Kingdom (UK) port callings to estimate typical UK emission factors by ship type and size and to determine how well existing global data and available databases represent UK shipping activity. The results highlight that although ship type is a crucial determinant of emissions, vessel size is also important, particularly for smaller ships where the variance in emission factors is greatest. Existing, globally averaged data correlating ship size with emissions agree well with the UK data. However, the relatively higher proportion of smaller ships satisfying a UK demand for short sea shipping results in a skew towards higher typical emission factors, principally within the general cargo, product and chemical tanker categories. This bias is most visible when emissions per individual ship calling are estimated. Incorporating

Estimating the Grain Size Distribution of Mars based on Fragmentation Theory and Observations

Science.gov (United States)

Charalambous, C.; Pike, W. T.; Golombek, M.

2017-12-01

We present here a fundamental extension to the fragmentation theory [1] which yields estimates of the distribution of particle sizes of a planetary surface. The model is valid within the size regimes of surfaces whose genesis is best reflected by the evolution of fragmentation phenomena governed by either the process of meteoritic impacts, or by a mixture with aeolian transportation at the smaller sizes. The key parameter of the model, the regolith maturity index, can be estimated as an average of that observed at a local site using cratering size-frequency measurements, orbital and surface image-detected rock counts and observations of sub-mm particles at landing sites. Through validation of ground truth from previous landed missions, the basis of this approach has been used at the InSight landing ellipse on Mars to extrapolate rock size distributions in HiRISE images down to 5 cm rock size, both to determine the landing safety risk and the subsequent probability of obstruction by a rock of the deployed heat flow mole down to 3-5 m depth [2]. Here we focus on a continuous extrapolation down to 600 µm coarse sand particles, the upper size limit that may be present through aeolian processes [3]. The parameters of the model are first derived for the fragmentation process that has produced the observable rocks via meteorite impacts over time, and therefore extrapolation into a size regime that is affected by aeolian processes has limited justification without further refinement. Incorporating thermal inertia estimates, size distributions observed by the Spirit and Opportunity Microscopic Imager [4] and Atomic Force and Optical Microscopy from the Phoenix Lander [5], the model's parameters in combination with synthesis methods are quantitatively refined further to allow transition within the aeolian transportation size regime. In addition, due to the nature of the model emerging in fractional mass abundance, the percentage of material by volume or mass that resides

Revealing life-history traits by contrasting genetic estimations with predictions of effective population size.

Science.gov (United States)

Greenbaum, Gili; Renan, Sharon; Templeton, Alan R; Bouskila, Amos; Saltz, David; Rubenstein, Daniel I; Bar-David, Shirli

2017-12-22

Effective population size, a central concept in conservation biology, is now routinely estimated from genetic surveys and can also be theoretically predicted from demographic, life-history, and mating-system data. By evaluating the consistency of theoretical predictions with empirically estimated effective size, insights can be gained regarding life-history characteristics and the relative impact of different life-history traits on genetic drift. These insights can be used to design and inform management strategies aimed at increasing effective population size. We demonstrated this approach by addressing the conservation of a reintroduced population of Asiatic wild ass (Equus hemionus). We estimated the variance effective size (N ev ) from genetic data (N ev =24.3) and formulated predictions for the impacts on N ev of demography, polygyny, female variance in lifetime reproductive success (RS), and heritability of female RS. By contrasting the genetic estimation with theoretical predictions, we found that polygyny was the strongest factor affecting genetic drift because only when accounting for polygyny were predictions consistent with the genetically measured N ev . The comparison of effective-size estimation and predictions indicated that 10.6% of the males mated per generation when heritability of female RS was unaccounted for (polygyny responsible for 81% decrease in N ev ) and 19.5% mated when female RS was accounted for (polygyny responsible for 67% decrease in N ev ). Heritability of female RS also affected N ev ; hf2=0.91 (heritability responsible for 41% decrease in N ev ). The low effective size is of concern, and we suggest that management actions focus on factors identified as strongly affecting Nev, namely, increasing the availability of artificial water sources to increase number of dominant males contributing to the gene pool. This approach, evaluating life-history hypotheses in light of their impact on effective population size, and contrasting

Estimating the size of non-observed economy in Croatia using the MIMIC approach

OpenAIRE

Vjekoslav Klaric

2011-01-01

This paper gives a quick overview of the approaches that have been used in the research of shadow economy, starting with the defi nitions of the terms “shadow economy” and “non-observed economy”, with the accent on the ISTAT/Eurostat framework. Several methods for estimating the size of the shadow economy and the non-observed economy are then presented. The emphasis is placed on the MIMIC approach, one of the methods used to estimate the size of the nonobserved economy. After a glance at the ...

APPLICATION OF FUZZY LOGIC BASED APPAREL SIZE FINDER IN ONLINE MARKETING

Directory of Open Access Journals (Sweden)

DEMIR Murat

2017-05-01

Full Text Available The emergence of online retailing has been one of the most significant developments in business history. Altough proportion of apparel sales in online retailing also has been shown rapid increase, there are some significant barriers to overcome for expanding this market share. It is seen in literature that there are many researchers point out that finding right size apparel is the one of the most significant problems in online retailing. There are many study to solve this problem but still there is not an exact solution yet. Creating 3D avatars for virtual try on or scanning body measurements of consumers have been used to solved this problem but any study has not come up with a reliable solution. In this study, a fuzzy logic based apparel size finder website is proposed. The benefits and working princible of this website are also explained. In this website, both of consumers and retailers can create a profile page for sharing products or following each other. Once consumers follow a profile of retailer, they can see the right size of any shared apparel. On the other hand, retailers can also directly send message to certain users for certain size apparel. This system brings advantages for both parties. Consumers can reach the correct size of apparel and retailers can reach to target customer. It is assumed that creating website alike this or application of existing online retailers will help to reduce return in apparel online retailing as well as it may help to expand online retailing.

Market segmentation of mobile communications in SEE region

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Domazet Anto

2006-01-01

Full Text Available In the focus of all activities are customers of mobile services on mobile communications market. As the basis of telecommunication network and services development, as also for creating an optimal marketing-mix from mobile operators' side, we have investigated the needs, motivations and customer behavior and have made analysis mobile communication customers on the SEE Region market. The aim of this analysis is identification of the regional segments and following their growth, size and profitability. At the end, we have contributed the suggestions for creating the marketing-mix using a strategy of marketing differentiation, which implicit optimal combination of all marketing-mix elements for each regional segment separately. For identified segments we have set up an estimation model of significant key factors on the particular segments, because of more efficient creation of marketing instruments.

Modeling grain-size dependent bias in estimating forest area: a regional application

Science.gov (United States)

Daolan Zheng; Linda S. Heath; Mark J. Ducey

2008-01-01

A better understanding of scaling-up effects on estimating important landscape characteristics (e.g. forest percentage) is critical for improving ecological applications over large areas. This study illustrated effects of changing grain sizes on regional forest estimates in Minnesota, Wisconsin, and Michigan of the USA using 30-m land-cover maps (1992 and 2001)...

Population size estimation of men who have sex with men through the network scale-up method in Japan.

Directory of Open Access Journals (Sweden)

Satoshi Ezoe

Full Text Available BACKGROUND: Men who have sex with men (MSM are one of the groups most at risk for HIV infection in Japan. However, size estimates of MSM populations have not been conducted with sufficient frequency and rigor because of the difficulty, high cost and stigma associated with reaching such populations. This study examined an innovative and simple method for estimating the size of the MSM population in Japan. We combined an internet survey with the network scale-up method, a social network method for estimating the size of hard-to-reach populations, for the first time in Japan. METHODS AND FINDINGS: An internet survey was conducted among 1,500 internet users who registered with a nationwide internet-research agency. The survey participants were asked how many members of particular groups with known population sizes (firepersons, police officers, and military personnel they knew as acquaintances. The participants were also asked to identify the number of their acquaintances whom they understood to be MSM. Using these survey results with the network scale-up method, the personal network size and MSM population size were estimated. The personal network size was estimated to be 363.5 regardless of the sex of the acquaintances and 174.0 for only male acquaintances. The estimated MSM prevalence among the total male population in Japan was 0.0402% without adjustment, and 2.87% after adjusting for the transmission error of MSM. CONCLUSIONS: The estimated personal network size and MSM prevalence seen in this study were comparable to those from previous survey results based on the direct-estimation method. Estimating population sizes through combining an internet survey with the network scale-up method appeared to be an effective method from the perspectives of rapidity, simplicity, and low cost as compared with more-conventional methods.

Benefits and challenges of using social media in marketing strategy:investigating small- and medium-sized companies in the Oulu region

OpenAIRE

Orajärvi, P. (Paavo)

2016-01-01

Abstract This thesis explains what social media marketing is as a phenomenon and what kind of roles it can fill in a company’s overall marketing strategies. The thesis also provides very practical information on how small/medium-sized companies can use social media channels in their daily marketing activities. This has been achieved through a literature review on the topic supported by an empirical multi-case study. The mot...

Estimation of mean grain size of seafloor sediments using neural network

Digital Repository Service at National Institute of Oceanography (India)

De, C.; Chakraborty, B.

The feasibility of an artificial neural network based approach is investigated to estimate the values of mean grain size of seafloor sediments using four dominant echo features, extracted from acoustic backscatter data. The acoustic backscatter data...

Is the market size hypothesis relevant for Botswana? Vector error correction framework

Directory of Open Access Journals (Sweden)

Kunofiwa Tsaurai

2015-10-01

Full Text Available The current study investigated the relevancy of the market size hypothesis of FDI in Botswana in Botswana using the VECM approach with data ranging from 1975 to 2013. The study used FDI net inflows (% of GDP as a measure of FDI and GDP per capita as a proxy of market size. The findings of the study are threefold: (1 observed that there exists a long run uni-directional causality relationship running from GDP per capita to FDI in Botswana, (2 there is no long run causality running from FDI to GDP per capita in Botswana between 1975 and 2013 and (3 failed to establish any short run causality either from GDP per capita to FDI or from FDI to GDP per capita in Botswana. Although, GDP per capita of Botswana was a conditional characteristic that attracted FDI, Botswana did not economically benefit from FDI net inflows during the period from 1975 to 2013. The findings defied the theory that mentions that FDI brings into the host country an improvement of human capital development and technology improvement among other advantages which boost economic growth. Possibly, there are other host country characteristics that Botswana needs to address if it hopes to benefit from FDI. The current study recommends further research to find out which are the other conditional characteristics that Botswana authorities need to put in place in ensure that FDI inflows is translated into economic benefits for the country

Estimating the size of the homeless population in Budapest, Hungary

NARCIS (Netherlands)

David, B; Snijders, TAB

In this study we try to estimate the size of the homeless population in Budapest by using two - non-standard - sampling methods: snowball sampling and capture-recapture method. Using two methods and three different data sets we are able to compare the methods as well as the results, and we also

State of the art in the estimation of energy prices in the spot market

International Nuclear Information System (INIS)

Botero B, Sergio; Cano C, Jovan A

2007-01-01

Since the start energy markets deregulation in the world, several spot market (short term) price prediction methods have been developed? this article identifies and compares the main methods of prediction used in Colombia and other international markets. With this review it is possible to determine the state of the knowledge in the specific subject and then to look for the development of new forecasting techniques that can contribute to the solution of this problem. The prediction horizon is something that must be taken into account in the review of the several techniques, given that both the magnitude of the final model of estimation, and the time series treatment type, depend on this horizon.

Transmission Bottleneck Size Estimation from Pathogen Deep-Sequencing Data, with an Application to Human Influenza A Virus.

Science.gov (United States)

Sobel Leonard, Ashley; Weissman, Daniel B; Greenbaum, Benjamin; Ghedin, Elodie; Koelle, Katia

2017-07-15

The bottleneck governing infectious disease transmission describes the size of the pathogen population transferred from the donor to the recipient host. Accurate quantification of the bottleneck size is particularly important for rapidly evolving pathogens such as influenza virus, as narrow bottlenecks reduce the amount of transferred viral genetic diversity and, thus, may decrease the rate of viral adaptation. Previous studies have estimated bottleneck sizes governing viral transmission by using statistical analyses of variants identified in pathogen sequencing data. These analyses, however, did not account for variant calling thresholds and stochastic viral replication dynamics within recipient hosts. Because these factors can skew bottleneck size estimates, we introduce a new method for inferring bottleneck sizes that accounts for these factors. Through the use of a simulated data set, we first show that our method, based on beta-binomial sampling, accurately recovers transmission bottleneck sizes, whereas other methods fail to do so. We then apply our method to a data set of influenza A virus (IAV) infections for which viral deep-sequencing data from transmission pairs are available. We find that the IAV transmission bottleneck size estimates in this study are highly variable across transmission pairs, while the mean bottleneck size of 196 virions is consistent with a previous estimate for this data set. Furthermore, regression analysis shows a positive association between estimated bottleneck size and donor infection severity, as measured by temperature. These results support findings from experimental transmission studies showing that bottleneck sizes across transmission events can be variable and influenced in part by epidemiological factors. IMPORTANCE The transmission bottleneck size describes the size of the pathogen population transferred from the donor to the recipient host and may affect the rate of pathogen adaptation within host populations. Recent

Participation of smaller size renewable generation in the electricity market trade in UK: Analyses and approaches

DEFF Research Database (Denmark)

Romanovsky, G.; Xydis, G.; Mutale, J.

2011-01-01

a number of specific historical, technical and economic reasons that significantly influenced the ability of the smaller size RES/DG to participate in the electricity market and in provision of balancing services in accordance with the UK National Grid requirements. This paper discusses some perspectives...

Hospital and Health Insurance Markets Concentration and Inpatient Hospital Transaction Prices in the U.S. Health Care Market.

Science.gov (United States)

Dauda, Seidu

2018-04-01

To examine the effects of hospital and insurer markets concentration on transaction prices for inpatient hospital services. Measures of hospital and insurer markets concentration derived from American Hospital Association and HealthLeaders-InterStudy data are linked to 2005-2008 inpatient administrative data from Truven Health MarketScan Databases. Uses a reduced-form price equation, controlling for cost and demand shifters and accounting for possible endogeneity of market concentration using instrumental variables (IV) technique. The findings suggest that greater hospital concentration raises prices, whereas greater insurer concentration depresses prices. A hypothetical merger between two of five equally sized hospitals is estimated to increase hospital prices by about 9 percent (p costs. © Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

The Effect of Childhood Family Size on Fertility in Adulthood: New Evidence From IV Estimation.

Science.gov (United States)

Cools, Sara; Kaldager Hart, Rannveig

2017-02-01

Although fertility is positively correlated across generations, the causal effect of children's experience with larger sibships on their own fertility in adulthood is poorly understood. With the sex composition of the two firstborn children as an instrumental variable, we estimate the effect of sibship size on adult fertility using high-quality data from Norwegian administrative registers. Our study sample is all firstborns or second-borns during the 1960s in Norwegian families with at least two children (approximately 110,000 men and 104,000 women). An additional sibling has a positive effect on male fertility, mainly causing them to have three children themselves, but has a negative effect on female fertility at the same margin. Investigation into mediators reveals that mothers of girls shift relatively less time from market to family work when an additional child is born. We speculate that this scarcity in parents' time makes girls aware of the strains of life in large families, leading them to limit their own number of children in adulthood.

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.

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.

Results and evaluation of a survey to estimate Pacific walrus population size, 2006

Science.gov (United States)

Speckman, Suzann G.; Chernook, Vladimir I.; Burn, Douglas M.; Udevitz, Mark S.; Kochnev, Anatoly A.; Vasilev, Alexander; Jay, Chadwick V.; Lisovsky, Alexander; Fischbach, Anthony S.; Benter, R. Bradley

2011-01-01

In spring 2006, we conducted a collaborative U.S.-Russia survey to estimate abundance of the Pacific walrus (Odobenus rosmarus divergens). The Bering Sea was partitioned into survey blocks, and a systematic random sample of transects within a subset of the blocks was surveyed with airborne thermal scanners using standard strip-transect methodology. Counts of walruses in photographed groups were used to model the relation between thermal signatures and the number of walruses in groups, which was used to estimate the number of walruses in groups that were detected by the scanner but not photographed. We also modeled the probability of thermally detecting various-sized walrus groups to estimate the number of walruses in groups undetected by the scanner. We used data from radio-tagged walruses to adjust on-ice estimates to account for walruses in the water during the survey. The estimated area of available habitat averaged 668,000 km2 and the area of surveyed blocks was 318,204 km2. The number of Pacific walruses within the surveyed area was estimated at 129,000 with 95% confidence limits of 55,000 to 507,000 individuals. This value can be used by managers as a minimum estimate of the total population size.

Implicit price of mussel characteristics in the auction market

DEFF Research Database (Denmark)

Nguyen, Thong Tien

2012-01-01

This study explores desired and undesired characteristics of mussels in wholesale market by applying hedonic price analysis. Transaction data in auction market in Yerseke, the Netherlands, was used to estimate linear and semi-log price models. Meat content and size count, which are measured...... of raw mussels are significant discounting factors on the price. The study also investigates the impact of farming locations and seasons on the price and the price trend during the period of 2002–2009....

Specific activity of uranium and thorium in marketable rock phosphate as a function of particle size

Energy Technology Data Exchange (ETDEWEB)

Metzger, R; McKlveen, J W [Arizona State Univ., Tempe (USA); Jenkins, R [Phillip Morris Research Center, Richmond, VA (USA); McDowell, W J [Oak Ridge National Lab., TN (USA)

1980-07-01

Marketable rock phosphate fertilizer from Florida was classified into seven particle size fractions ranging from 149 ..mu..m to less than 0.5 ..mu..m using a Bahco Microparticle Classifier and air elutriation. The resulting size fractions were assayed for U and /sup 230/Th by solvent extraction and liquid scintillation ..cap alpha..-spectroscopy. Results indicated that the specific activity of U and /sup 230/Th increased with decreasing particle size. Maximum activities of 110 pCi/g U and 50 pCi/g /sup 230/Th were found in particles less than 1.0 ..mu..m in aerodynamic diameter. Qualitative emission spectrographic analysis of the fractions revealed that the concentrations of Al, Cu, Mg, Na, Ti and Zn also increased with decreasing particle size.

Optimal capacity and buffer size estimation under Generalized Markov Fluids Models and QoS parameters

International Nuclear Information System (INIS)

Bavio, José; Marrón, Beatriz

2014-01-01

Quality of service (QoS) for internet traffic management requires good traffic models and good estimation of sharing network resource. A link of a network processes all traffic and it is designed with certain capacity C and buffer size B. A Generalized Markov Fluid model (GMFM), introduced by Marrón (2011), is assumed for the sources because describes in a versatile way the traffic, allows estimation based on traffic traces, and also consistent effective bandwidth estimation can be done. QoS, interpreted as buffer overflow probability, can be estimated for GMFM through the effective bandwidth estimation and solving the optimization problem presented in Courcoubetis (2002), the so call inf-sup formulas. In this work we implement a code to solve the inf-sup problem and other optimization related with it, that allow us to do traffic engineering in links of data networks to calculate both, minimum capacity required when QoS and buffer size are given or minimum buffer size required when QoS and capacity are given

Replicon sizes in mammalian cells as estimated by an x-ray plus bromodeoxyuridine photolysis method

International Nuclear Information System (INIS)

Kapp, L.N.; Painter, R.B.

1978-01-01

A new method is described for estimating replicon sizes in mammalian cells. Cultures were pulse labeled with [ 3 H]thymidine ([ 3 H]TdR) and bromodeoxyuridine (BrDUrd) for up to 1 h. The lengths of the resulting labeled regions of DNA, L/sub obs/, were estimated by a technique wherein the change in molecular weight of nascent DNA strands, induced by 313 nm light, is measured by velocity sedimentation in alkaline sucrose gradients. If cells are exposed to 1,000 rads of x rays immediately before pulse labeling, initiation of replicon operation is blocked, although chain elongation proceeds almost normally. Under these conditions L/sub obs/ continues to increase only until operating replicons have completed their replication. This value for L/sub obs/ then remains constant as long as the block to initiation remains and represents an estimate for the average size of replicons operating in the cells before x irradiation. For human diploid fibroblasts and human HeLa cells this estimated average size is approximately 17 μM, whereas for Chinese hamster ovary cells, the average replicon size is about 42 μM

Estimation of sample size and testing power (part 6).

Science.gov (United States)

Hu, Liang-ping; Bao, Xiao-lei; Guan, Xue; Zhou, Shi-guo

2012-03-01

The design of one factor with k levels (k ≥ 3) refers to the research that only involves one experimental factor with k levels (k ≥ 3), and there is no arrangement for other important non-experimental factors. This paper introduces the estimation of sample size and testing power for quantitative data and qualitative data having a binary response variable with the design of one factor with k levels (k ≥ 3).

Wind farm production cost: Optimum turbine size and farm capacity in the actual market

Energy Technology Data Exchange (ETDEWEB)

Laali, A.R.; Meyer, J.L.; Bellot, C. [Electricite de France, Chatou (France); Louche, A. [Espace de Recherche, Ajaccio (France)

1996-12-31

Several studies are undertaken in R&D Division of EDF in collaboration with ERASME association in order to have a good knowledge of the wind energy production costs. These studies are performed in the framework of a wind energy monitoring project and concern the influence of a few parameters like wind farm capacity, turbine size and wind speed on production costs, through an analysis of the actual market trend. Some 50 manufacturers and 140 different kind of wind turbines are considered for this study. The minimum production cost is situated at 800/900 kW wind turbine rated power. This point will probably move to more important powers in the future. This study is valid only for average conditions and some special parameters like particular climate conditions or lack of infrastructure for a special site the could modify the results shown on the curves. The variety of wind turbines (rated power as a function of rotor diameter, height and specific rated power) in the actual market is analyzed. A brief analysis of the market trend is also performed. 7 refs., 7 figs.

A study on the effect of size and ratio of book value to market value on excessive return

Directory of Open Access Journals (Sweden)

Seyed Mohsen Tabatabaei Mozdabadi

2012-09-01

Full Text Available Stock market plays an important role on demonstrating economy direction and it provides good opportunities for people who wish to purchase a small portion of different firms' shares. In this paper, we propose an empirical study to measure the impact of the market size and the ratio of book value on market value on excessive return. The study gathers the necessary information from some of active stock shares traded on Tehran Stock Exchange over the period of 2010-2011. The proposed model of this paper uses linear regression analysis to investigate the relationship between the excessive return and other factors. The study divides the information into seven equal groups and fits the regression model using ordinary least square technique. The results indicate that there is a negative relationship between size and excessive return and a positive relationship between the ratio of BV/MV and excessive return. Although the results of both tests are positive, we have to be more cautious about what have reported on the second hypothesis.

Impact of Formal Financial Market Participation on Farm Size and Expenditure on Variable Farm Inputs: The Case of Maize Farmers in Ghana

OpenAIRE

Awunyo-Vitor, Dadson; Al-Hassan, Ramatu M.; Sarpong, Daniel B.

2014-01-01

The study examined maize farmers’ participation in the formal financial market and its impact on farm size and expenditure on variable farm inputs. A multistage sampling method was used in selecting 595 maize farmers from the seven districts in Ashanti and Brong Ahafo Regions of Ghana. A structured questionnaire and interview schedule were used to elicit information from the respondents. The impact of formal financial market participation on farm size and expenditure on variable inputs was es...

[What determines the market shares of the health funds in Israeli localities?].

Science.gov (United States)

Shmueli, Amir; Engelcin-Nissan, Esti

2011-08-01

Four health funds operate nationally in Israel, but their local market shares vary dramatically across localities. To identify the main localities' characteristics which affect the size of the market shares of the various health funds. A total of 60 Localities with more than 20,000 inhabitants were chosen. The following Localities' characteristics were retrieved for the year 2004: the market shares of the four health funds, average income, standardized mortality ratio (SMR), periphery index, the age structure, the distance from the nearest general hospital, the share of Arab population, and size. Four market share equations were estimated using SURE (seemingly unrelated regressions estimation), allowing for inter-equation correlations. The results show that the market shares of the different health funds are affected by different factors. Clalit Health Services' (CHS) share increases with the distance from Tel Aviv and SMR, and decreases with the level of mean income and the distance from the nearest CHS hospital. Leumit's market share increases only with the distance from a CHS's hospital. The market share of Maccabi Healthcare Services is higher in central localities, Jewish localities, small cities and further away from a non-CHS hospital. Meuhedet's market share is higher in big cities, rich and healthy localities, and in Localities which are further away from CHS's hospitals. These findings indicate that the presence of the health funds in different Localities varies according to the Localities' characteristics. There appears to be a market segmentation and "specialization" of certain health funds in specific populations, and of the other health funds in the rest of the population.

Modeling of magnetic fields on a cylindrical surface and associated parameter estimation for development of a size sensor

International Nuclear Information System (INIS)

Zhang, Song; Rajamani, Rajesh

2016-01-01

This paper develops analytical sensing principles for estimation of circumferential size of a cylindrical surface using magnetic sensors. An electromagnet and magnetic sensors are used on a wearable band for measurement of leg size. In order to enable robust size estimation during rough real-world use of the wearable band, three estimation algorithms are developed based on models of the magnetic field variation over a cylindrical surface. The magnetic field models developed include those for a dipole and for a uniformly magnetized cylinder. The estimation algorithms used include a linear regression equation, an extended Kalman filter and an unscented Kalman filter. Experimental laboratory tests show that the size sensor in general performs accurately, yielding sub-millimeter estimation errors. The unscented Kalman filter yields the best performance that is robust to bias and misalignment errors. The size sensor developed herein can be used for monitoring swelling due to fluid accumulation in the lower leg and a number of other biomedical applications. (paper)

Market Survey Turkey. Electricity Market

International Nuclear Information System (INIS)

2008-12-01

The present market survey presents the Turkish power market and derives business opportunities and prospects for Dutch trade and industry. This market survey has been carried out for the following four, from time to time overlapping, sectors that have been identified by EVD as potential opportunities for Dutch small and medium-sized enterprises (SME): renewable energy, energy efficiency, electricity generation, electricity distribution

The Role and Importance of the Lease Towards the Farms’ Size Increase

Directory of Open Access Journals (Sweden)

Gabriel Popescu

2007-01-01

Full Text Available The lease reactivation, within the agrarian relations, at year 1994, was considered as a "normal economic phenomenon". The rent, as a price of the land lease, should equal gratify the interest of those two marketer partners, land owner and leaseholder. The estimations prove the restrictive character of the lease for owner of the land, not through the hectare's quantum, but through the total income size gained by the family, as a result of the farm low size, or of the plot of land gave to lease. The lease as a landed market's action has demonstrated its role within the agriculture farm size increase, merely through the restrictive manufactures factors character at the renters, which has substituted to the households.

A mixed latent class Markov approach for estimating labour market mobility with multiple indicators and retrospective interrogation

NARCIS (Netherlands)

Bassi, Francesca; Croon, M.A.; Vidotto, D.

Measurement errors can induce bias in the estimation of transitions, leading to erroneous conclusions about labour market dynamics. Traditional literature on gross flows estimation is based on the assumption that measurement errors are uncorrelated over time. This assumption is not realistic in many

Background parenchymal enhancement in breast MRIs of breast cancer patients: Impact on tumor size estimation

International Nuclear Information System (INIS)

Baek, Ji Eun; Kim, Sung Hun; Lee, Ah Won

2014-01-01

Objective: To evaluate whether the degree of background parenchymal enhancement affects the accuracy of tumor size estimation based on breast MRI. Methods: Three hundred and twenty-two patients who had known breast cancer and underwent breast MRIs were recruited in our study. The total number of breast cancer cases was 339. All images were assessed retrospectively for the level of background parenchymal enhancement based on the BI-RADS criteria. Maximal lesion diameters were measured on the MRIs, and tumor types (mass vs. non-mass) were assessed. Tumor size differences between the MRI-based estimates and estimates based on pathological examinations were analyzed. The relationship between accuracy and tumor types and clinicopathologic features were also evaluated. Results: The cases included minimal (47.5%), mild (28.9%), moderate (12.4%) and marked background parenchymal enhancement (11.2%). The tumors of patients with minimal or mild background parenchymal enhancement were more accurately estimated than those of patients with moderate or marked enhancement (72.1% vs. 56.8%; p = 0.003). The tumors of women with mass type lesions were significantly more accurately estimated than those of the women with non-mass type lesions (81.6% vs. 28.6%; p < 0.001). The tumor of women negative for HER2 was more accurately estimated than those of women positive for HER2 (72.2% vs. 51.6%; p = 0.047). Conclusion: Moderate and marked background parenchymal enhancement is related to the inaccurate estimation of tumor size based on MRI. Non-mass type breast cancer and HER2-positive breast cancer are other factors that may cause inaccurate assessment of tumor size

Estimating the accuracy of optic nerve sheath diameter measurement using a pocket-sized, handheld ultrasound on a simulation model.

Science.gov (United States)

Johnson, Garrett G R J; Zeiler, Frederick A; Unger, Bertram; Hansen, Gregory; Karakitsos, Dimitrios; Gillman, Lawrence M

2016-12-01

Ultrasound measurement of optic nerve sheath diameter (ONSD) appears to be a promising, rapid, non-invasive bedside tool for identification of elevated intra-cranial pressure. With improvements in ultrasound technology, machines are becoming smaller; however, it is unclear if these ultra-portable handheld units have the resolution to make these measurements precisely. In this study, we estimate the accuracy of ONSD measurement in a pocket-sized ultrasound unit. Utilizing a locally developed, previously validated model of the eye, ONSD was measured by two expert observers, three times with two machines and on five models with different optic nerve sheath sizes. A pocket ultrasound (Vscan, GE Healthcare) and a standard portable ultrasound (M-Turbo, SonoSite) were used to measure the models. Data was analyzed by Bland-Altman plot and intra-class correlation coefficient (ICC). The ICC between raters for the SonoSite was 0.878, and for the Vscan was 0.826. The between-machine agreement ICC was 0.752. Bland-Altman agreement analysis between the two ultrasound methods showed an even spread across the range of sheath sizes, and that the Vscan tended to read on average 0.33 mm higher than the SonoSite for each measurement, with a standard deviation of 0.65 mm. Accurate ONSD measurement may be possible utilizing pocket-sized, handheld ultrasound devices despite their small screen size, lower resolution, and lower probe frequencies. Further study in human subjects is warranted for all newer handheld ultrasound models as they become available on the market.

Study on The Volatility Spillover Effect Between The Second Board Market And The Small and Medium -sized Board Market in China%我国创业板市场与中小板市场间的波动溢出效应研究

Institute of Scientific and Technical Information of China (English)

耿庆峰

2013-01-01

基于MVGARCH-BEKK模型对创业板市场与中小板市场间的波动溢出效应进行研究，研究结果表明：创业板市场存在波动的集聚性和持久性，中小板市场不存在波动的集聚性，但存在波动的持久性；创业板市场与中小板市场间存在波动溢出效应，但创业板市场对中小板市场的波动持久性影响显著，中小板市场对创业板市场的波动集聚性影响显著；创业板市场与中小板市场间的波动溢出效应程度均不大，但中小板市场对创业板市场的波动溢出效应程度要大于创业板市场对中小板市场的波动溢出效应程度，表明老市场向新兴市场的信息流动量较大。%Based on the MVGARCH-BEKK model ,this paper empirically analyzes the volatility spillover effect between growth enterprise market and small and medium -sized market.The evidence shows that there are volatili-ty clustering and persistence in growth enterprise market , whille, only volatility persistence has been found in small and medium-sized market.The volatility spillover effect between gorwth enterprise market and small and medium-sized market has been found ,but the volatility persistence from growth enterprise market to small and medium -sized market is significant , while, the volatility clustering from small and medium -sized market to growth enter-prise market is significant.The volatility spillover effect between growth enterprise market and small and medium -sized market is small , and the degree of the volatility spillover effect from small and medium -sized market to growth enterprise market is smaller ,whant means that there are much more information flow from old capital market to emerging market .

A model to estimate the size of nanoparticle agglomerates in gas−solid fluidized beds

Energy Technology Data Exchange (ETDEWEB)

Martín, Lilian de, E-mail: L.DeMartinMonton@tudelft.nl; Ommen, J. Ruud van [Delft University of Technology, Department of Chemical Engineering (Netherlands)

2013-11-15

The estimation of nanoparticle agglomerates’ size in fluidized beds remains an open challenge, mainly due to the difficulty of characterizing the inter-agglomerate van der Waals force. The current approach is to describe micron-sized nanoparticle agglomerates as micron-sized particles with 0.1–0.2-μm asperities. This simplification does not capture the influence of the particle size on the van der Waals attraction between agglomerates. In this paper, we propose a new description where the agglomerates are micron-sized particles with nanoparticles on the surface, acting as asperities. As opposed to previous models, here the van der Waals force between agglomerates decreases with an increase in the particle size. We have also included an additional force due to the hydrogen bond formation between the surfaces of hydrophilic and dry nanoparticles. The average size of the fluidized agglomerates has been estimated equating the attractive force obtained from this method to the weight of the individual agglomerates. The results have been compared to 54 experimental values, most of them collected from the literature. Our model approximates without a systematic error the size of most of the nanopowders, both in conventional and centrifugal fluidized beds, outperforming current models. Although simple, the model is able to capture the influence of the nanoparticle size, particle density, and Hamaker coefficient on the inter-agglomerate forces.

A model to estimate the size of nanoparticle agglomerates in gas−solid fluidized beds

International Nuclear Information System (INIS)

Martín, Lilian de; Ommen, J. Ruud van

2013-01-01

The estimation of nanoparticle agglomerates’ size in fluidized beds remains an open challenge, mainly due to the difficulty of characterizing the inter-agglomerate van der Waals force. The current approach is to describe micron-sized nanoparticle agglomerates as micron-sized particles with 0.1–0.2-μm asperities. This simplification does not capture the influence of the particle size on the van der Waals attraction between agglomerates. In this paper, we propose a new description where the agglomerates are micron-sized particles with nanoparticles on the surface, acting as asperities. As opposed to previous models, here the van der Waals force between agglomerates decreases with an increase in the particle size. We have also included an additional force due to the hydrogen bond formation between the surfaces of hydrophilic and dry nanoparticles. The average size of the fluidized agglomerates has been estimated equating the attractive force obtained from this method to the weight of the individual agglomerates. The results have been compared to 54 experimental values, most of them collected from the literature. Our model approximates without a systematic error the size of most of the nanopowders, both in conventional and centrifugal fluidized beds, outperforming current models. Although simple, the model is able to capture the influence of the nanoparticle size, particle density, and Hamaker coefficient on the inter-agglomerate forces

Facility and market factors affecting transitions from nursing home to community.

Science.gov (United States)

Arling, Greg; Abrahamson, Kathleen A; Cooke, Valerie; Kane, Robert L; Lewis, Teresa

2011-09-01

Research into nursing home transitions has given limited attention to the facility or community contexts. To identify facility and market factors affecting transitions of nursing home residents back to the community. Multilevel models were used to estimate effects of facility and market factors on facility-level community discharge rates after controlling for resident demographic, health, and functional conditions. Facility discharge rates were adjusted using Empirical Bayes estimation. Annual cohort of first-time admissions (N=24,648) to 378 Minnesota nursing facilities in 75 nursing home markets from July 2005 to June 2006. Community discharge within 90 days of admission; facility occupancy, payer mix, ownership, case-mix acuity, size, admissions from hospitals, nurse staffing level, and proportion of admissions preferring or having support to return to the community; and nursing market population size, average occupancy, market concentration, and availability of home and community-based services. Rates of community discharge (Empirical Bayes residual) were highest in facilities with more residents preferring community discharge, more Medicare days, higher nurse staffing levels, and higher occupancy. In addition, facilities had higher community discharge rates if they were located in markets with a greater ratio of home and community-based services recipients to nursing home residents and with larger populations. State Medicaid programs should undertake system-level interventions that encourage nursing facilities to reduce unused bed capacity, balance the mix of payers, invest in nurse staffing, and take other steps to promote community discharges. In addition, states should increase home and community-based services, particularly in markets with low community discharge rates.

Sample size methods for estimating HIV incidence from cross-sectional surveys.

Science.gov (United States)

Konikoff, Jacob; Brookmeyer, Ron

2015-12-01

Understanding HIV incidence, the rate at which new infections occur in populations, is critical for tracking and surveillance of the epidemic. In this article, we derive methods for determining sample sizes for cross-sectional surveys to estimate incidence with sufficient precision. We further show how to specify sample sizes for two successive cross-sectional surveys to detect changes in incidence with adequate power. In these surveys biomarkers such as CD4 cell count, viral load, and recently developed serological assays are used to determine which individuals are in an early disease stage of infection. The total number of individuals in this stage, divided by the number of people who are uninfected, is used to approximate the incidence rate. Our methods account for uncertainty in the durations of time spent in the biomarker defined early disease stage. We find that failure to account for this uncertainty when designing surveys can lead to imprecise estimates of incidence and underpowered studies. We evaluated our sample size methods in simulations and found that they performed well in a variety of underlying epidemics. Code for implementing our methods in R is available with this article at the Biometrics website on Wiley Online Library. © 2015, The International Biometric Society.

Inbound Marketing - the most important digital marketing strategy

OpenAIRE

PATRUTIU-BALTES Loredana

2017-01-01

Digital marketing has a major importance in the marketing strategy of any company regardless of sector, size or country of origin. Thus, more than ever, in order to remain competitive, companies are forced to exploit this form of marketing, which essentially can bring huge benefits at low costs. The main form of digital marketing is the inbound marketing, which represents an organic marketing form, based on the close relationship ...

Marketing research of the chocolate market in Macedonia

Directory of Open Access Journals (Sweden)

Jovanov-Marjanova Tamara

2012-01-01

Full Text Available The consumer market in Macedonia and the chocolate market in particular, are overtaken from many foreign brands. The domestic companies, disregarding their size, are losing market share to the competitors with stronger strategies. This paper shows the existing weaknesses in the current strategies of the domestic companies through case study of the 2 largest confectionery producers in Macedonia on one side, and discovers the consumer behavior and preferences toward FMCG and chocolate through market research and analysis of a purposive statistical sample of 300 consumers on the other. The applied research techniques for the need of the consumer research were questionnaires and in depth interviews with the firms' managers. The analysis clearly indicates that with the adequate market research, i.e. implementation of the market research models and techniques a basis for competitive and successful marketing strategy can be created, not only by large corporations, but by individuals/owners of small and medium sized companies as well.

THE STRATEGIC RESPONSE OF SMALL AND MEDIUM-SIZED ENTERPRISE SECTOR FIRMS TO THE SINGLE EUROPEAN MARKET - A COMPARATIVE STUDY

OpenAIRE

BRICKAU, RALF ALEXANDER

1994-01-01

The creation of the post-1992 European Single Market represents a significant change in the business environment confronting firms throughout Europe. Although there is an extensive source of literature available on appropriate strategic responses to the Single Market, very few of these writings contain guidance specifically related to the situation facing small and medium- sized enterprises (SMEs). The objectives of this study are i) to determine important veu-iables which m...

Problems of Transition from a Planned to a Market Economy

OpenAIRE

Krelle, Wilhelm

2000-01-01

The paper shows that a transition from a planned to a market economy implies an important change of the structure of production, i. e. a reallocation of resources which takes time and induces sufferings for some people. These sufferings may be reduced by subsidization of some sectors, with some negative effects on GDP and growth if subsidization exceeds a certain size. The time tillthe economy in transition reaches an ``old" market economy (asymptotically or totally) is estimated by different...

Estimating a reasonable patient panel size for primary care physicians with team-based task delegation.

Science.gov (United States)

Altschuler, Justin; Margolius, David; Bodenheimer, Thomas; Grumbach, Kevin

2012-01-01

PURPOSE Primary care faces the dilemma of excessive patient panel sizes in an environment of a primary care physician shortage. We aimed to estimate primary care panel sizes under different models of task delegation to nonphysician members of the primary care team. METHODS We used published estimates of the time it takes for a primary care physician to provide preventive, chronic, and acute care for a panel of 2,500 patients, and modeled how panel sizes would change if portions of preventive and chronic care services were delegated to nonphysician team members. RESULTS Using 3 assumptions about the degree of task delegation that could be achieved (77%, 60%, and 50% of preventive care, and 47%, 30%, and 25% of chronic care), we estimated that a primary care team could reasonably care for a panel of 1,947, 1,523, or 1,387 patients. CONCLUSIONS If portions of preventive and chronic care services are delegated to nonphysician team members, primary care practices can provide recommended preventive and chronic care with panel sizes that are achievable with the available primary care workforce.

COMMODITY MARKET MATH MODELS

Directory of Open Access Journals (Sweden)

Boris V. Mednikov

2015-01-01

Full Text Available The article describes enterprise mathmodels, its interactions with environment in commodity market and quantitativeconditions for its success and the crisis in such kind of interaction. Showed: the number of commodity market successfulparticipants should be certain, regardless of market size; any size commodity market, including monopolistic, is assuccessful as producers’ average activity dynamics is balanced with consumers’average activity dynamics.

B-graph sampling to estimate the size of a hidden population

NARCIS (Netherlands)

Spreen, M.; Bogaerts, S.

2015-01-01

Link-tracing designs are often used to estimate the size of hidden populations by utilizing the relational links between their members. A major problem in studies of hidden populations is the lack of a convenient sampling frame. The most frequently applied design in studies of hidden populations is

Forecasting the U.S. market for windpower

International Nuclear Information System (INIS)

Hoffman, G.; Garges, K.

1996-01-01

Projections to the middle of the next century indicate that future wind-electricity is likely to cost from 5.5 to 7.7 cents per kWh, and that its US market share may be around 4 to 5% of the total. Wind-turbines produce electricity cheaper than nuclear powerplants and may soon become competitive with fossil-fueled generators. As wind's clear superiority to nuclear accelerates, utilities may need new marketability assessments: this one is based on their own criterion, namely the outlook for the cost of electricity (CoE) to the customer. The study compiled others' estimates for distant-future wind-CoE (WCoE) and fossil-CoE (FCoE), and a way of forecasting wind-electricity market size 50 years hence

Market power in electricity markets: Beyond concentration measures

International Nuclear Information System (INIS)

Borenstein, S.; Bushnell, J.; Knittel, C.R.

1999-01-01

The wave of electricity market restructuring both within the US and abroad has brought the issue of horizontal market power to the forefront of energy policy. Traditionally, estimation and prediction of market power has relied heavily on concentration measures. In this paper, the authors discuss the weaknesses of concentration measures as a viable measure of market power in the electricity industry, and they propose an alternative method based on market simulations that take advantage of existing plant level data. The authors discuss results from previous studies they have performed, and present new results that allow for the detection of threshold demand levels where market power is likely to be a problem. In addition, the authors analyze the impact of that recent divestitures in the California electricity market will have on estimated market power. They close with a discussion of the policy implications of the results

Evaluation of a low-head recirculating aquaculture system used for rearing Florida pompano to market size

Science.gov (United States)

A low-head recirculating aquaculture system (RAS) was evaluated for the production Florida pompano Trachinotus carolinus from juvenile to market size. The RAS consisted of three dual-drain, 3-m diameter culture tanks of 7.8 m3 volume each, two 0.7-m3 moving bed bioreactors filled 67% with K1 kaldnes...

Market Orientation and Business Performance: a Study of Interrelationships and Effects in a Small sized Hotels within Lagos State Metropolis

Directory of Open Access Journals (Sweden)

P.K.A. Ladipo

2016-12-01

Full Text Available The relationship between market orientation and business performance has been a subject of debate in marketing literature. To date, there is no consensus opinion and empirical study in the context of small sized-hotels in Nigeria is scanty. This study examines the relationship between market orientation and business performance. Cross-sectional survey research design was adopted. Questionnaire was used to obtained data from 300 employees of the selected hotels within Lagos metropolis. Data collected were analyzed using correlation and regression analysis. The results suggest that only customer orientation is significantly contributing to the performance of the small sized hotel operators. Specifically, both competitor orientation and inter-functional coordination, though practiced by the hotels are not significantly linked to its performance. Furthermore, the study discovered that market orientation practices significantly influence business performance of the selected hotels. Based on the findings, the study concludes that hotel operators need market orientation practices to enhance their performance. Hence, market orientation will continue to be a vital strategy not only in improving firm’s understanding of customers’ and competitors, but to enhance synergy across the organization. From the preceding conclusion, the study recommends that hotel operators should commit substantial resources and effort in cultivating a customer oriented culture, and transmit it across the organization to create strategic alignment. Furthermore, the competitive environment should be closely monitored to identify profitable business opportunity and threats that could affect their growth and sustainability.

Estimation of LOCA break size using cascaded Fuzzy neural networks

Energy Technology Data Exchange (ETDEWEB)

Choi, Geon Pil; Yoo, Kwae Hwan; Back, Ju Hyun; Na, Man Gyun [Dept. of Nuclear Engineering, Chosun University, Gwangju (Korea, Republic of)

2017-04-15

Operators of nuclear power plants may not be equipped with sufficient information during a loss-of-coolant accident (LOCA), which can be fatal, or they may not have sufficient time to analyze the information they do have, even if this information is adequate. It is not easy to predict the progression of LOCAs in nuclear power plants. Therefore, accurate information on the LOCA break position and size should be provided to efficiently manage the accident. In this paper, the LOCA break size is predicted using a cascaded fuzzy neural network (CFNN) model. The input data of the CFNN model are the time-integrated values of each measurement signal for an initial short-time interval after a reactor scram. The training of the CFNN model is accomplished by a hybrid method combined with a genetic algorithm and a least squares method. As a result, LOCA break size is estimated exactly by the proposed CFNN model.

Estimating the non-market costs and benefits of native woodland restoration using the contingent valuation method.

OpenAIRE

MacMillan, Douglas C.; Duff, Elizabeth I.

1998-01-01

The restoration of native forests is an important priority for forestry and conservation organizations in the United Kingdom. The economic case for public sector support for native woodland restoration in the United Kingdom rests almost entirely on the provision of non-market benefits related to wildlife, landscape and recreational opportunities. This paper describes a discrete choice contingent valuation (CV) to estimate the value of the non-market benefits of restoring two native pinewood f...

Optically-derived estimates of phytoplankton size class and taxonomic group biomass in the Eastern Subarctic Pacific Ocean

Science.gov (United States)

Zeng, Chen; Rosengard, Sarah Z.; Burt, William; Peña, M. Angelica; Nemcek, Nina; Zeng, Tao; Arrigo, Kevin R.; Tortell, Philippe D.

2018-06-01

We evaluate several algorithms for the estimation of phytoplankton size class (PSC) and functional type (PFT) biomass from ship-based optical measurements in the Subarctic Northeast Pacific Ocean. Using underway measurements of particulate absorption and backscatter in surface waters, we derived estimates of PSC/PFT based on chlorophyll-a concentrations (Chl-a), particulate absorption spectra and the wavelength dependence of particulate backscatter. Optically-derived [Chl-a] and phytoplankton absorption measurements were validated against discrete calibration samples, while the derived PSC/PFT estimates were validated using size-fractionated Chl-a measurements and HPLC analysis of diagnostic photosynthetic pigments (DPA). Our results showflo that PSC/PFT algorithms based on [Chl-a] and particulate absorption spectra performed significantly better than the backscatter slope approach. These two more successful algorithms yielded estimates of phytoplankton size classes that agreed well with HPLC-derived DPA estimates (RMSE = 12.9%, and 16.6%, respectively) across a range of hydrographic and productivity regimes. Moreover, the [Chl-a] algorithm produced PSC estimates that agreed well with size-fractionated [Chl-a] measurements, and estimates of the biomass of specific phytoplankton groups that were consistent with values derived from HPLC. Based on these results, we suggest that simple [Chl-a] measurements should be more fully exploited to improve the classification of phytoplankton assemblages in the Northeast Pacific Ocean.

Conditional CAPM: Time-varying Betas in the Brazilian Market

Directory of Open Access Journals (Sweden)

Frances Fischberg Blank

2014-10-01

Full Text Available The conditional CAPM is characterized by time-varying market beta. Based on state-space models approach, beta behavior can be modeled as a stochastic process dependent on conditioning variables related to business cycle and estimated using Kalman filter. This paper studies alternative models for portfolios sorted by size and book-to-market ratio in the Brazilian stock market and compares their adjustment to data. Asset pricing tests based on time-series and cross-sectional approaches are also implemented. A random walk process combined with conditioning variables is the preferred model, reducing pricing errors compared to unconditional CAPM, but the errors are still significant. Cross-sectional test show that book-to-market ratio becomes less relevant, but past returns still capture cross-section variation

Solution to marketing; Marketing solution

Energy Technology Data Exchange (ETDEWEB)

Takahashi, Y.; Fukushima, T.; Kanezuka, A. [Fuji Electric Co. Ltd., Tokyo (Japan)

2000-05-10

Fuji Electric in cooperation with Citation Japan Co., Ltd. and Asahi Arthur Andersen Limited has developed the 'marketing analysis support system' which supports the integrated analysis of evaluation factors of various dimensions and efficient commodity development and demand estimation in the enterprise. With this system, more precise marketing analysis and estimation are made possible by analyzing a commodity into evaluation factors from psychological and physical points of view and further making various multivariate analyses. (author)

Beak measurements of octopus ( Octopus variabilis) in Jiaozhou Bay and their use in size and biomass estimation

Science.gov (United States)

Xue, Ying; Ren, Yiping; Meng, Wenrong; Li, Long; Mao, Xia; Han, Dongyan; Ma, Qiuyun

2013-09-01

Cephalopods play key roles in global marine ecosystems as both predators and preys. Regressive estimation of original size and weight of cephalopod from beak measurements is a powerful tool of interrogating the feeding ecology of predators at higher trophic levels. In this study, regressive relationships among beak measurements and body length and weight were determined for an octopus species ( Octopus variabilis), an important endemic cephalopod species in the northwest Pacific Ocean. A total of 193 individuals (63 males and 130 females) were collected at a monthly interval from Jiaozhou Bay, China. Regressive relationships among 6 beak measurements (upper hood length, UHL; upper crest length, UCL; lower hood length, LHL; lower crest length, LCL; and upper and lower beak weights) and mantle length (ML), total length (TL) and body weight (W) were determined. Results showed that the relationships between beak size and TL and beak size and ML were linearly regressive, while those between beak size and W fitted a power function model. LHL and UCL were the most useful measurements for estimating the size and biomass of O. variabilis. The relationships among beak measurements and body length (either ML or TL) were not significantly different between two sexes; while those among several beak measurements (UHL, LHL and LBW) and body weight (W) were sexually different. Since male individuals of this species have a slightly greater body weight distribution than female individuals, the body weight was not an appropriate measurement for estimating size and biomass, especially when the sex of individuals in the stomachs of predators was unknown. These relationships provided essential information for future use in size and biomass estimation of O. variabilis, as well as the estimation of predator/prey size ratios in the diet of top predators.

Identifying grain-size dependent errors on global forest area estimates and carbon studies

Science.gov (United States)

Daolan Zheng; Linda S. Heath; Mark J. Ducey

2008-01-01

Satellite-derived coarse-resolution data are typically used for conducting global analyses. But the forest areas estimated from coarse-resolution maps (e.g., 1 km) inevitably differ from a corresponding fine-resolution map (such as a 30-m map) that would be closer to ground truth. A better understanding of changes in grain size on area estimation will improve our...

Content marketing - the fundamental tool of digital marketing

OpenAIRE

Loredana PATRUTIU BALTES

2015-01-01

In the era of digitalization, the importance of digital marketing has increased from one year to another as part of the marketing strategy practiced by organizations of any type and any size. Given that digital marketing requires the existence of a content marketing, the success or the failure of the company’s online communication depends to a significant extent on the quality of its content marketing. In this context, besides promoting a high quality of the content marketing, ...

Determining an Estimate of an Equivalence Relation for Moderate and Large Sized Sets

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Leszek Klukowski

2017-01-01

Full Text Available This paper presents two approaches to determining estimates of an equivalence relation on the basis of pairwise comparisons with random errors. Obtaining such an estimate requires the solution of a discrete programming problem which minimizes the sum of the differences between the form of the relation and the comparisons. The problem is NP hard and can be solved with the use of exact algorithms for sets of moderate size, i.e. about 50 elements. In the case of larger sets, i.e. at least 200 comparisons for each element, it is necessary to apply heuristic algorithms. The paper presents results (a statistical preprocessing, which enable us to determine the optimal or a near-optimal solution with acceptable computational cost. They include: the development of a statistical procedure producing comparisons with low probabilities of errors and a heuristic algorithm based on such comparisons. The proposed approach guarantees the applicability of such estimators for any size of set. (original abstract

Characterization of spherical core–shell particles by static light scattering. Estimation of the core- and particle-size distributions

International Nuclear Information System (INIS)

Clementi, Luis A.; Vega, Jorge R.; Gugliotta, Luis M.; Quirantes, Arturo

2012-01-01

A numerical method is proposed for the characterization of core–shell spherical particles from static light scattering (SLS) measurements. The method is able to estimate the core size distribution (CSD) and the particle size distribution (PSD), through the following two-step procedure: (i) the estimation of the bivariate core–particle size distribution (C–PSD), by solving a linear ill-conditioned inverse problem through a generalized Tikhonov regularization strategy, and (ii) the calculation of the CSD and the PSD from the estimated C–PSD. First, the method was evaluated on the basis of several simulated examples, with polystyrene–poly(methyl methacrylate) core–shell particles of different CSDs and PSDs. Then, two samples of hematite–Yttrium basic carbonate core–shell particles were successfully characterized. In all analyzed examples, acceptable estimates of the PSD and the average diameter of the CSD were obtained. Based on the single-scattering Mie theory, the proposed method is an effective tool for characterizing core–shell colloidal particles larger than their Rayleigh limits without requiring any a-priori assumption on the shapes of the size distributions. Under such conditions, the PSDs can always be adequately estimated, while acceptable CSD estimates are obtained when the core/shell particles exhibit either a high optical contrast, or a moderate optical contrast but with a high ‘average core diameter’/‘average particle diameter’ ratio. -- Highlights: ► Particles with core–shell morphology are characterized by static light scattering. ► Core size distribution and particle size distribution are successfully estimated. ► Simulated and experimental examples are used to validate the numerical method. ► The positive effect of a large core/shell optical contrast is investigated. ► No a-priori assumption on the shapes of the size distributions is required.

Estimating population size of a nocturnal burrow-nesting seabird using acoustic monitoring and habitat mapping

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Steffen Oppel

2014-04-01

Full Text Available Population size assessments for nocturnal burrow-nesting seabirds are logistically challenging because these species are active in colonies only during darkness and often nest on remote islands where manual inspections of breeding burrows are not feasible. Many seabird species are highly vocal, and recent technological innovations now make it possible to record and quantify vocal activity in seabird colonies. Here we test the hypothesis that remotely recorded vocal activity in Cory’s shearwater (Calonectris borealis breeding colonies in the North Atlantic increases with nest density, and combined this relationship with cliff habitat mapping to estimate the population size of Cory’s shearwaters on the island of Corvo (Azores. We deployed acoustic recording devices in 9 Cory’s shearwater colonies of known size to establish a relationship between vocal activity and local nest density (slope = 1.07, R2 = 0.86, p < 0.001. We used this relationship to predict the nest density in various cliff habitat types and produced a habitat map of breeding cliffs to extrapolate nest density around the island of Corvo. The mean predicted nest density on Corvo ranged from 6.6 (2.1–16.2 to 27.8 (19.5–36.4 nests/ha. Extrapolation of habitat-specific nest densities across the cliff area of Corvo resulted in an estimate of 6326 Cory’s shearwater nests (95% confidence interval: 3735–10,524. This population size estimate is similar to previous assessments, but is too imprecise to detect moderate changes in population size over time. While estimating absolute population size from acoustic recordings may not be sufficiently precise, the strong positive relationship that we found between local nest density and recorded calling rate indicates that passive acoustic monitoring may be useful to document relative changes in seabird populations over time.

Stock Market Integration Measurement: Investigation of Malaysia and Singapore Stock Markets

OpenAIRE

B. K. Yeoh; Z. Arsad; C. W. Hooy

2010-01-01

This paper tests the level of market integration between Malaysia and Singapore stock markets with the world market. Kalman Filter (KF) methodology is used on the International Capital Asset Pricing Model (ICAPM) and the pricing errors estimated within the framework of ICAPM are used as a measure of market integration or segmentation. The advantage of the KF technique is that it allows for time-varying coefficients in estimating ICAPM and hence able to capture the varying degree of market int...

Relative efficiency of unequal versus equal cluster sizes in cluster randomized trials using generalized estimating equation models.

Science.gov (United States)

Liu, Jingxia; Colditz, Graham A

2018-05-01

There is growing interest in conducting cluster randomized trials (CRTs). For simplicity in sample size calculation, the cluster sizes are assumed to be identical across all clusters. However, equal cluster sizes are not guaranteed in practice. Therefore, the relative efficiency (RE) of unequal versus equal cluster sizes has been investigated when testing the treatment effect. One of the most important approaches to analyze a set of correlated data is the generalized estimating equation (GEE) proposed by Liang and Zeger, in which the "working correlation structure" is introduced and the association pattern depends on a vector of association parameters denoted by ρ. In this paper, we utilize GEE models to test the treatment effect in a two-group comparison for continuous, binary, or count data in CRTs. The variances of the estimator of the treatment effect are derived for the different types of outcome. RE is defined as the ratio of variance of the estimator of the treatment effect for equal to unequal cluster sizes. We discuss a commonly used structure in CRTs-exchangeable, and derive the simpler formula of RE with continuous, binary, and count outcomes. Finally, REs are investigated for several scenarios of cluster size distributions through simulation studies. We propose an adjusted sample size due to efficiency loss. Additionally, we also propose an optimal sample size estimation based on the GEE models under a fixed budget for known and unknown association parameter (ρ) in the working correlation structure within the cluster. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Effects of LiDAR point density, sampling size and height threshold on estimation accuracy of crop biophysical parameters.

Science.gov (United States)

Luo, Shezhou; Chen, Jing M; Wang, Cheng; Xi, Xiaohuan; Zeng, Hongcheng; Peng, Dailiang; Li, Dong

2016-05-30

Vegetation leaf area index (LAI), height, and aboveground biomass are key biophysical parameters. Corn is an important and globally distributed crop, and reliable estimations of these parameters are essential for corn yield forecasting, health monitoring and ecosystem modeling. Light Detection and Ranging (LiDAR) is considered an effective technology for estimating vegetation biophysical parameters. However, the estimation accuracies of these parameters are affected by multiple factors. In this study, we first estimated corn LAI, height and biomass (R2 = 0.80, 0.874 and 0.838, respectively) using the original LiDAR data (7.32 points/m2), and the results showed that LiDAR data could accurately estimate these biophysical parameters. Second, comprehensive research was conducted on the effects of LiDAR point density, sampling size and height threshold on the estimation accuracy of LAI, height and biomass. Our findings indicated that LiDAR point density had an important effect on the estimation accuracy for vegetation biophysical parameters, however, high point density did not always produce highly accurate estimates, and reduced point density could deliver reasonable estimation results. Furthermore, the results showed that sampling size and height threshold were additional key factors that affect the estimation accuracy of biophysical parameters. Therefore, the optimal sampling size and the height threshold should be determined to improve the estimation accuracy of biophysical parameters. Our results also implied that a higher LiDAR point density, larger sampling size and height threshold were required to obtain accurate corn LAI estimation when compared with height and biomass estimations. In general, our results provide valuable guidance for LiDAR data acquisition and estimation of vegetation biophysical parameters using LiDAR data.

RELATIONSHIP DERIVATIVES FINANCIAL MARKETS, MONEY AND STOCK MARKETS AS A SUBSYSTEM OF FINANCIAL MARKET

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Yulia Yelnikova

2016-11-01

Full Text Available Under conditions of intensive strengthening of globalization of world financial markets and deepening of the crisis, the main source of which are financial markets, financial derivatives market is rapidly developing. In such circumstances, we observe very active growing demand for tools, the main purpose of which is to reduce the financial risk – derivatives. Outlined trend has also involved Ukraine. In this connection, there is an objective need to develop estimate the interconnection of the money and stock markets and derivatives market. It should be kept in mind that achieving the outlined goal is possible only under condition of the full understanding of the scientific and methodological principles of the development of these markets. Purpose is to estimate the interconnection of the money and stock markets and derivatives market by building a mathematical model of system of structural equations that will promote the compilation of scientifically based program of derivatives market. Methodology. By using methods of economic-mathematical modelling were estimated the degree of influence of studied markets factors on financial derivatives market development and by changing this or that factor were predicted future trends of its operations. Results of the survey showed the current state and problems of derivatives market functioning. At the same time, our study allowed us to talk, that factors of the money and stock markets have a different impact on the derivatives market. So, the majority of money market factors have a reverse influence on the development of derivatives market. Instead, the stock market has a direct influence. Practical implications. The proposed scientific and methodical approach to evaluating the impact of factors on the derivatives market allows: influenced by different factors; to conduct a qualitative interpretation of the quantitative changes in the level of market development; to form a complete system of state

Power and sample-size estimation for microbiome studies using pairwise distances and PERMANOVA.

Science.gov (United States)

Kelly, Brendan J; Gross, Robert; Bittinger, Kyle; Sherrill-Mix, Scott; Lewis, James D; Collman, Ronald G; Bushman, Frederic D; Li, Hongzhe

2015-08-01

The variation in community composition between microbiome samples, termed beta diversity, can be measured by pairwise distance based on either presence-absence or quantitative species abundance data. PERMANOVA, a permutation-based extension of multivariate analysis of variance to a matrix of pairwise distances, partitions within-group and between-group distances to permit assessment of the effect of an exposure or intervention (grouping factor) upon the sampled microbiome. Within-group distance and exposure/intervention effect size must be accurately modeled to estimate statistical power for a microbiome study that will be analyzed with pairwise distances and PERMANOVA. We present a framework for PERMANOVA power estimation tailored to marker-gene microbiome studies that will be analyzed by pairwise distances, which includes: (i) a novel method for distance matrix simulation that permits modeling of within-group pairwise distances according to pre-specified population parameters; (ii) a method to incorporate effects of different sizes within the simulated distance matrix; (iii) a simulation-based method for estimating PERMANOVA power from simulated distance matrices; and (iv) an R statistical software package that implements the above. Matrices of pairwise distances can be efficiently simulated to satisfy the triangle inequality and incorporate group-level effects, which are quantified by the adjusted coefficient of determination, omega-squared (ω2). From simulated distance matrices, available PERMANOVA power or necessary sample size can be estimated for a planned microbiome study. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Understanding Market Size and Reporting Gaps for Paediatric TB in Indonesia, Nigeria and Pakistan: Supporting Improved Treatment of Childhood TB in the Advent of New Medicines.

Science.gov (United States)

Coghlan, Renia; Gardiner, Elizabeth; Amanullah, Farhana; Ihekweazu, Chikwe; Triasih, Rina; Grzemska, Malgorzata; Sismanidis, Charalambos

2015-01-01

We sought to understand gaps in reporting childhood TB cases among public and private sector health facilities (dubbed "non-NTP" facilities) outside the network of national TB control programmes, and the resulting impact of under-reporting on estimates of paediatric disease burden and market demand for new medicines. Exploratory assessments were carried out in Indonesia, Nigeria and Pakistan, reaching a range of facility types in two selected areas of each country. Record reviews and interviews of healthcare providers were carried out to assess numbers of unreported paediatric TB cases, diagnostic pathways followed and treatment regimens prescribed. A total of 985 unreported diagnosed paediatric TB cases were identified over a three month period in 2013 in Indonesia from 64 facilities, 463 in Pakistan from 35 facilities and 24 in Nigeria from 20 facilities. These represent an absolute additional annualised yield to 2013 notifications reported to WHO of 15% for Indonesia, 2% for Nigeria and 7% for Pakistan. Only 12% of all facilities provided age and sex-disaggregated data. Findings highlight the challenges of confirming childhood TB. Diagnosis patterns in Nigeria highlight a very low suspicion for childhood TB. Providers note the need for paediatric medicines aligned to WHO recommendations. This study emphasises the impact of incomplete reporting on the estimation of disease burden and potential market size of paediatric TB medicines. Further studies on "hubs" (facilities treating large numbers of childhood TB cases) will improve our understanding of the epidemic, support introduction efforts for new treatments and better measure markets for new paediatric medicines.

Do small labor market entry cohorts reduce unemployment?

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Alfred Garloff

2013-09-01

Full Text Available BACKGROUND Germany, like many OECD countries, faces a shift in the age composition of its population,and will face an even more drastic demographic change in the years ahead. From a theoretical point of view, decreasing cohort sizes may on the one hand reduce unemployment due to inverse cohort crowding or, on the other hand, increase unemploymentif companies reduce jobs disproportionately. Consequently, the actual effect of cohort shrinkage on employment and unemployment is an empirical question. OBJECTIVE We quantitatively assess the relationship between (unemployment and cohort sizes. METHODS We analyze a long panel of population and labor-market data for Western German labor market regions. We isolate the direct, statistical effect of aging in a decomposition approach and estimate the overall effect by regression. In this context, we account for the likely endogeneity of cohort size due to migration of the young workforce across regions using lagged births as instrument. RESULTS The direct effect of the age composition of the labor force on unemployment is negligible.In contrast, the elasticities of unemployment and employment with regard to the labor-market entry cohort's size are significantly positive or negative, respectively. The causal effect indicates an over-elastic reaction by unemployment. CONCLUSIONS Our results provide good news for the Western German labor market: small entry cohorts are indeed likely to decrease the overall unemployment rate and thus to improve the situation of job seekers. Accordingly, we find the employment rate is positively affected by a decrease in the youth proportion.

Integrating citizen-science data with movement models to estimate the size of a migratory golden eagle population

Science.gov (United States)

Andrew J. Dennhardt; Adam E. Duerr; David Brandes; Todd E. Katzner

2015-01-01

Estimating population size is fundamental to conservation and management. Population size is typically estimated using survey data, computer models, or both. Some of the most extensive and often least expensive survey data are those collected by citizen-scientists. A challenge to citizen-scientists is that the vagility of many organisms can complicate data collection....

Population size estimation in Yellowstone wolves with error-prone noninvasive microsatellite genotypes.

Science.gov (United States)

Creel, Scott; Spong, Goran; Sands, Jennifer L; Rotella, Jay; Zeigle, Janet; Joe, Lawrence; Murphy, Kerry M; Smith, Douglas

2003-07-01

Determining population sizes can be difficult, but is essential for conservation. By counting distinct microsatellite genotypes, DNA from noninvasive samples (hair, faeces) allows estimation of population size. Problems arise because genotypes from noninvasive samples are error-prone, but genotyping errors can be reduced by multiple polymerase chain reaction (PCR). For faecal genotypes from wolves in Yellowstone National Park, error rates varied substantially among samples, often above the 'worst-case threshold' suggested by simulation. Consequently, a substantial proportion of multilocus genotypes held one or more errors, despite multiple PCR. These genotyping errors created several genotypes per individual and caused overestimation (up to 5.5-fold) of population size. We propose a 'matching approach' to eliminate this overestimation bias.

Market assessment of tuberculosis diagnostics in Brazil in 2012.

Science.gov (United States)

2014-01-01

Improved diagnostics for the diagnosis of tuberculosis (TB) are urgently needed. However, test developers and investors require market size data to support new product development. This study assessed the served available market for TB diagnostics in Brazil in 2012 and the market segmentation in the public and private sectors. Data were collected on test volumes done in the public and private sectors for the diagnosis of latent and active TB, drug susceptibility testing and treatment follow-up. Tests included were tuberculin skin tests, interferon-gamma releases assays, smear microscopy, solid and liquid cultures, nucleic acid amplification tests and phenotypic drug susceptibility tests. The data were collected by means of an electronic survey via the Brazilian State laboratories and from sales information provided by manufacturers. Test costs for the public sector were calculated using a components approach, while costs for the private sector were based on prices paid by patients. The overall market value (expenditure) for the entire country was calculated using the public sector test costs. During 2012, an estimated total of 2.4 million TB diagnostic tests were done in Brazil, resulting in an estimated overall market value of USD 17.2 million. The public sector accounted for 91% of the test volumes and 88% of the market value. Smear microscopy was the most commonly test (n = 1.3 million; 55% of total) at an estimated value of USD 3.7 million. Culture overall (n = 302,761) represented 13% of test volumes and 40% (USD 6.9 million) of the market value. On average, USD 208 was spent on TB diagnostics for every notified TB patient in Brazil, in 2012. The TB diagnostics market value in Brazil in 2012 was over USD 17 million. These study results will help test developers to understand the current and potential market for replacement or add-on diagnostic technologies.

Harem: Hardwood lumber remanufacturing program for maxmizing value based on size, grade and current market prices

Science.gov (United States)

C.J. Schwehm; P. Klinkhachorn; Charles W. McMillin; Henry A. Huber

1990-01-01

This paper describes an expert system computer program which will determine the optimum way to edge and trim a hardwood board so as to yield the highest dollar value based on the grade, size of each board, and current market prices. The program uses the Automated Hardwood Lumber Grading Program written by Klinkhachorn, et al. for determining the grade of each board...

Using Diffraction Tomography to Estimate Marine Animal Size

Science.gov (United States)

Jaffe, J. S.; Roberts, P.

In this article we consider the development of acoustic methods which have the potential to size marine animals. The proposed technique uses scattered sound in order to invert for both animal size and shape. The technique uses the Distorted Wave Born Approximation (DWBA) in order to model sound scattered from these organisms. The use of the DWBA also provides a valuable context for formulating data analysis techniques in order to invert for parameters of the animal. Although 3-dimensional observations can be obtained from a complete set of views, due to the difficulty of collecting full 3-dimensional scatter, it is useful to simplify the inversion by approximating the animal by a few parameters. Here, the animals are modeled as 3-dimensional ellipsoids. This reduces the complexity of the problem to a determination of the 3 semi axes for the x, y and z dimensions from just a few radial spokes through the 3-dimensional Fourier Transform. In order to test the idea, simulated scatter data is taken from a 3-dimensional model of a marine animal and the resultant data are inverted in order to estimate animal shape

Estimating sample size for landscape-scale mark-recapture studies of North American migratory tree bats

Science.gov (United States)

Ellison, Laura E.; Lukacs, Paul M.

2014-01-01

Concern for migratory tree-roosting bats in North America has grown because of possible population declines from wind energy development. This concern has driven interest in estimating population-level changes. Mark-recapture methodology is one possible analytical framework for assessing bat population changes, but sample size requirements to produce reliable estimates have not been estimated. To illustrate the sample sizes necessary for a mark-recapture-based monitoring program we conducted power analyses using a statistical model that allows reencounters of live and dead marked individuals. We ran 1,000 simulations for each of five broad sample size categories in a Burnham joint model, and then compared the proportion of simulations in which 95% confidence intervals overlapped between and among years for a 4-year study. Additionally, we conducted sensitivity analyses of sample size to various capture probabilities and recovery probabilities. More than 50,000 individuals per year would need to be captured and released to accurately determine 10% and 15% declines in annual survival. To detect more dramatic declines of 33% or 50% survival over four years, then sample sizes of 25,000 or 10,000 per year, respectively, would be sufficient. Sensitivity analyses reveal that increasing recovery of dead marked individuals may be more valuable than increasing capture probability of marked individuals. Because of the extraordinary effort that would be required, we advise caution should such a mark-recapture effort be initiated because of the difficulty in attaining reliable estimates. We make recommendations for what techniques show the most promise for mark-recapture studies of bats because some techniques violate the assumptions of mark-recapture methodology when used to mark bats.

Bayesian estimation of covariance matrices: Application to market risk management at EDF

International Nuclear Information System (INIS)

Jandrzejewski-Bouriga, M.

2012-01-01

In this thesis, we develop new methods of regularized covariance matrix estimation, under the Bayesian setting. The regularization methodology employed is first related to shrinkage. We investigate a new Bayesian modeling of covariance matrix, based on hierarchical inverse-Wishart distribution, and then derive different estimators under standard loss functions. Comparisons between shrunk and empirical estimators are performed in terms of frequentist performance under different losses. It allows us to highlight the critical importance of the definition of cost function and show the persistent effect of the shrinkage-type prior on inference. In a second time, we consider the problem of covariance matrix estimation in Gaussian graphical models. If the issue is well treated for the decomposable case, it is not the case if you also consider non-decomposable graphs. We then describe a Bayesian and operational methodology to carry out the estimation of covariance matrix of Gaussian graphical models, decomposable or not. This procedure is based on a new and objective method of graphical-model selection, combined with a constrained and regularized estimation of the covariance matrix of the model chosen. The procedures studied effectively manage missing data. These estimation techniques were applied to calculate the covariance matrices involved in the market risk management for portfolios of EDF (Electricity of France), in particular for problems of calculating Value-at-Risk or in Asset Liability Management. (author)

Fair market value

International Nuclear Information System (INIS)

Williams, J.

1991-01-01

This paper presents an examination of fair market value concepts as they pertain to producing petroleum properties. conventional petroleum economic theories of fair market value are examined in light of recent work on the market value of long-life reserves. Their work is expanded to show that sellers rely on comparable sales data for estimating FMV. Both results are used to suggest that current practices over-emphasize the discounted cash flow approach to estimating fair market value

The influence of body size on adult skeletal age estimation methods.

Science.gov (United States)

Merritt, Catherine E

2015-01-01

Accurate age estimations are essential to archaeological and forensic analyses. However, reliability for adult skeletal age estimations is poor, especially for individuals over the age of 40 years. This is the first study to show that body size influences skeletal age estimation. The İşcan et al., Lovejoy et al., Buckberry and Chamberlain, and Suchey-Brooks age methods were tested on 764 adult skeletons from the Hamann-Todd and William Bass Collections. Statures ranged from 1.30 to 1.93 m and body masses ranged from 24.0 to 99.8 kg. Transition analysis was used to evaluate the differences in the age estimations. For all four methods, the smallest individuals have the lowest ages at transition and the largest individuals have the highest ages at transition. Short and light individuals are consistently underaged, while tall and heavy individuals are consistently overaged. When femoral length and femoral head diameter are compared with the log-age model, results show the same trend as the known stature and body mass measurements. The skeletal remains of underweight individuals have fewer age markers while those of obese individuals have increased surface degeneration and osteophytic lipping. Tissue type and mechanical loading have been shown to affect bone turnover rates, and may explain the differing patterns of skeletal aging. From an archaeological perspective, the underaging of light, short individuals suggests the need to revisit the current research consensus on the young mortality rates of past populations. From a forensic perspective, understanding the influence of body size will impact efforts to identify victims of mass disasters, genocides, and homicides. © 2014 Wiley Periodicals, Inc.

Covariate adjustments in randomized controlled trials increased study power and reduced biasedness of effect size estimation.

Science.gov (United States)

Lee, Paul H

2016-08-01

This study aims to show that under several assumptions, in randomized controlled trials (RCTs), unadjusted, crude analysis will underestimate the Cohen's d effect size of the treatment, and an unbiased estimate of effect size can be obtained only by adjusting for all predictors of the outcome. Four simulations were performed to examine the effects of adjustment on the estimated effect size of the treatment and power of the analysis. In addition, we analyzed data from the Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) study (older adults aged 65-94), an RCT with three treatment arms and one control arm. We showed that (1) the number of unadjusted covariates was associated with the effect size of the treatment; (2) the biasedness of effect size estimation was minimized if all covariates were adjusted for; (3) the power of the statistical analysis slightly decreased with the number of adjusted noise variables; and (4) exhaustively searching the covariates and noise variables adjusted for can lead to exaggeration of the true effect size. Analysis of the ACTIVE study data showed that the effect sizes adjusting for covariates of all three treatments were 7.39-24.70% larger than their unadjusted counterparts, whereas the effect size would be elevated by at most 57.92% by exhaustively searching the variables adjusted for. All covariates of the outcome in RCTs should be adjusted for, and if the effect of a particular variable on the outcome is unknown, adjustment will do more good than harm. Copyright © 2016 Elsevier Inc. All rights reserved.

Conditional Relationship Between Beta and Return in the US Stock Market

Directory of Open Access Journals (Sweden)

Bing XIAO

2016-04-01

Full Text Available According to the CAPM, risk is measured by the beta, and the relation between required expected return and beta is linear. This paper examines the conditional relationship between beta and return in the US stock market. The conditional covariances and variances used to estimate beta are modeled as an ARCH process. The beta return relationship is tested upon the sign of the excess market return. The implication of the sign of the excess market return follows Morelli (2011. This study shows the importance of recognizing the sign of the excess market return when testing the beta-return relationship. The approach also allows us to distinguish the size effect and the effect of economic cycles.

Market Microstructure Effects on Firm Default Risk Evaluation

Directory of Open Access Journals (Sweden)

Flavia Barsotti

2016-07-01

Full Text Available Default probability is a fundamental variable determining the credit worthiness of a firm and equity volatility estimation plays a key role in its evaluation. Assuming a structural credit risk modeling approach, we study the impact of choosing different non parametric equity volatility estimators on default probability evaluation, when market microstructure noise is considered. A general stochastic volatility framework with jumps for the underlying asset dynamics is defined inside a Merton-like structural model. To estimate the volatility risk component of a firm we use high-frequency equity data: market microstructure noise is introduced as a direct effect of observing noisy high-frequency equity prices. A Monte Carlo simulation analysis is conducted to (i test the performance of alternative non-parametric equity volatility estimators in their capability of filtering out the microstructure noise and backing out the true unobservable asset volatility; (ii study the effects of different non-parametric estimation techniques on default probability evaluation. The impact of the non-parametric volatility estimators on risk evaluation is not negligible: a sensitivity analysis defined for alternative values of the leverage parameter and average jumps size reveals that the characteristics of the dataset are crucial to determine which is the proper estimator to consider from a credit risk perspective.

Market-based demand forecasting promotes informed strategic financial planning.

Science.gov (United States)

Beech, A J

2001-11-01

Market-based demand forecasting is a method of estimating future demand for a healthcare organization's services by using a broad range of data that describe the nature of demand within the organization's service area. Such data include the primary and secondary service areas, the service-area populations by various demographic groupings, discharge utilization rates, market size, and market share by service line and organizationwide. Based on observable market dynamics, strategic planners can make a variety of explicit assumptions about future trends regarding these data to develop scenarios describing potential future demand. Financial planners then can evaluate each scenario to determine its potential effect on selected financial and operational measures, such as operating margin, days cash on hand, and debt-service coverage, and develop a strategic financial plan that covers a range of contingencies.

Current Size and Remaining Market Potential of the U.S. Energy Service Company Industry

Energy Technology Data Exchange (ETDEWEB)

Stuart, Elizabeth [Ernest Orlando Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Larsen, Peter H. [Ernest Orlando Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Goldman, Charles A. [Ernest Orlando Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Gilligan, Donald [Ernest Orlando Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); National Association of Energy Services Companies

2013-06-27

In this study, we analyze the market size, growth projections and industry trends in the U.S. ESCO industry, drawing on information from interviews with ESCO executives conducted in late 2012. We define ESCOs as energy service companies for whom performance -based contracting is a key business activity; 45 companies met our definition of an ESCO. We were able to interview 35 of these companies, which represents ~78% response rate. The non-respondent ESCOs were small companies in terms of revenue, representing about 2% of industry revenues.

Tri-spine horseshoe crab, Tachypleus tridentatus (L. in Sabah, Malaysia: the adult body sizes and population estimate

Directory of Open Access Journals (Sweden)

Azwarfarid Manca

2017-09-01

Full Text Available The dwindling number of the tri-spine horseshoe crab, Tachypleus tridentatus has been reported globally and its status in Malaysia is not much known. Study on dimorphism in adult body sizes and population size estimation were conducted using capture–mark–recapture method of adult T. tridentatus in Tawau, Sabah. Camry the estimated population sizes of T. tridentatus ranged from 182 to 1095 with 95% confident limits of 56–42,942 individuals (Schnabel formula. The multivariate discriminant Hotelling’s T2 test verifies the sexual size dimorphism among the adult T. tridentatus with 97.7% separation among sexes (Hotelling’s T2 = 778.49, F = 152.85, p < 0.001 with females being larger and heavier than the male individuals. The number estimated from the study is the first reported for T. tridentatus in Malaysia, particularly in Sabah. Even though this number may slightly overestimate the actual population size in the area owing to the low number of individuals recaptured, for now it could serve as baseline data for horseshoe crab management purpose.

An Introduction to Confidence Intervals for Both Statistical Estimates and Effect Sizes.

Science.gov (United States)

Capraro, Mary Margaret

This paper summarizes methods of estimating confidence intervals, including classical intervals and intervals for effect sizes. The recent American Psychological Association (APA) Task Force on Statistical Inference report suggested that confidence intervals should always be reported, and the fifth edition of the APA "Publication Manual"…

Detecting spatial structures in throughfall data: The effect of extent, sample size, sampling design, and variogram estimation method

Science.gov (United States)

Voss, Sebastian; Zimmermann, Beate; Zimmermann, Alexander

2016-09-01

In the last decades, an increasing number of studies analyzed spatial patterns in throughfall by means of variograms. The estimation of the variogram from sample data requires an appropriate sampling scheme: most importantly, a large sample and a layout of sampling locations that often has to serve both variogram estimation and geostatistical prediction. While some recommendations on these aspects exist, they focus on Gaussian data and high ratios of the variogram range to the extent of the study area. However, many hydrological data, and throughfall data in particular, do not follow a Gaussian distribution. In this study, we examined the effect of extent, sample size, sampling design, and calculation method on variogram estimation of throughfall data. For our investigation, we first generated non-Gaussian random fields based on throughfall data with large outliers. Subsequently, we sampled the fields with three extents (plots with edge lengths of 25 m, 50 m, and 100 m), four common sampling designs (two grid-based layouts, transect and random sampling) and five sample sizes (50, 100, 150, 200, 400). We then estimated the variogram parameters by method-of-moments (non-robust and robust estimators) and residual maximum likelihood. Our key findings are threefold. First, the choice of the extent has a substantial influence on the estimation of the variogram. A comparatively small ratio of the extent to the correlation length is beneficial for variogram estimation. Second, a combination of a minimum sample size of 150, a design that ensures the sampling of small distances and variogram estimation by residual maximum likelihood offers a good compromise between accuracy and efficiency. Third, studies relying on method-of-moments based variogram estimation may have to employ at least 200 sampling points for reliable variogram estimates. These suggested sample sizes exceed the number recommended by studies dealing with Gaussian data by up to 100 %. Given that most previous

Evidence from a Large Sample on the Effects of Group Size and Decision-Making Time on Performance in a Marketing Simulation Game

Science.gov (United States)

Treen, Emily; Atanasova, Christina; Pitt, Leyland; Johnson, Michael

2016-01-01

Marketing instructors using simulation games as a way of inducing some realism into a marketing course are faced with many dilemmas. Two important quandaries are the optimal size of groups and how much of the students' time should ideally be devoted to the game. Using evidence from a very large sample of teams playing a simulation game, the study…

Evaluating the performance of species richness estimators: sensitivity to sample grain size

DEFF Research Database (Denmark)

Hortal, Joaquín; Borges, Paulo A. V.; Gaspar, Clara

2006-01-01

and several recent estimators [proposed by Rosenzweig et al. (Conservation Biology, 2003, 17, 864-874), and Ugland et al. (Journal of Animal Ecology, 2003, 72, 888-897)] performed poorly. 3.  Estimations developed using the smaller grain sizes (pair of traps, traps, records and individuals) presented similar....... Data obtained with standardized sampling of 78 transects in natural forest remnants of five islands were aggregated in seven different grains (i.e. ways of defining a single sample): islands, natural areas, transects, pairs of traps, traps, database records and individuals to assess the effect of using...

Experimental design and estimation of growth rate distributions in size-structured shrimp populations

International Nuclear Information System (INIS)

Banks, H T; Davis, Jimena L; Ernstberger, Stacey L; Hu, Shuhua; Artimovich, Elena; Dhar, Arun K

2009-01-01

We discuss inverse problem results for problems involving the estimation of probability distributions using aggregate data for growth in populations. We begin with a mathematical model describing variability in the early growth process of size-structured shrimp populations and discuss a computational methodology for the design of experiments to validate the model and estimate the growth-rate distributions in shrimp populations. Parameter-estimation findings using experimental data from experiments so designed for shrimp populations cultivated at Advanced BioNutrition Corporation are presented, illustrating the usefulness of mathematical and statistical modeling in understanding the uncertainty in the growth dynamics of such populations

How Big Is It Really? Assessing the Efficacy of Indirect Estimates of Body Size in Asian Elephants.

Directory of Open Access Journals (Sweden)

Simon N Chapman

Full Text Available Information on an organism's body size is pivotal in understanding its life history and fitness, as well as helping inform conservation measures. However, for many species, particularly large-bodied wild animals, taking accurate body size measurements can be a challenge. Various means to estimate body size have been employed, from more direct methods such as using photogrammetry to obtain height or length measurements, to indirect prediction of weight using other body morphometrics or even the size of dung boli. It is often unclear how accurate these measures are because they cannot be compared to objective measures. Here, we investigate how well existing estimation equations predict the actual body weight of Asian elephants Elephas maximus, using body measurements (height, chest girth, length, foot circumference and neck circumference taken directly from a large population of semi-captive animals in Myanmar (n = 404. We then define new and better fitting formulas to predict body weight in Myanmar elephants from these readily available measures. We also investigate whether the important parameters height and chest girth can be estimated from photographs (n = 151. Our results show considerable variation in the ability of existing estimation equations to predict weight, and that the equations proposed in this paper predict weight better in almost all circumstances. We also find that measurements from standardised photographs reflect body height and chest girth after applying minor adjustments. Our results have implications for size estimation of large wild animals in the field, as well as for management in captive settings.

Estimating the transmission potential of supercritical processes based on the final size distribution of minor outbreaks.

Science.gov (United States)

Nishiura, Hiroshi; Yan, Ping; Sleeman, Candace K; Mode, Charles J

2012-02-07

Use of the final size distribution of minor outbreaks for the estimation of the reproduction numbers of supercritical epidemic processes has yet to be considered. We used a branching process model to derive the final size distribution of minor outbreaks, assuming a reproduction number above unity, and applying the method to final size data for pneumonic plague. Pneumonic plague is a rare disease with only one documented major epidemic in a spatially limited setting. Because the final size distribution of a minor outbreak needs to be normalized by the probability of extinction, we assume that the dispersion parameter (k) of the negative-binomial offspring distribution is known, and examine the sensitivity of the reproduction number to variation in dispersion. Assuming a geometric offspring distribution with k=1, the reproduction number was estimated at 1.16 (95% confidence interval: 0.97-1.38). When less dispersed with k=2, the maximum likelihood estimate of the reproduction number was 1.14. These estimates agreed with those published from transmission network analysis, indicating that the human-to-human transmission potential of the pneumonic plague is not very high. Given only minor outbreaks, transmission potential is not sufficiently assessed by directly counting the number of offspring. Since the absence of a major epidemic does not guarantee a subcritical process, the proposed method allows us to conservatively regard epidemic data from minor outbreaks as supercritical, and yield estimates of threshold values above unity. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

E-marketing channels : The digital influence on small sized businesses

OpenAIRE

Lam, Linh

2010-01-01

The inception of e-marketing is from the middle of 1990s. Since then the number of companies who apply it are increasing. E-marketing can bring many advantages for business such as cost effective, worldwide reach and access, time, space, interactivity, value added and competition. The traditional ways of doing e-marketing are still going on. Yet, e-marketing having rising up provides not less convenience for businesses. The cost of conducting business is especially cheaper. It becomes the pro...

Performance and separation occurrence of binary probit regression estimator using maximum likelihood method and Firths approach under different sample size

Science.gov (United States)

Lusiana, Evellin Dewi

2017-12-01

The parameters of binary probit regression model are commonly estimated by using Maximum Likelihood Estimation (MLE) method. However, MLE method has limitation if the binary data contains separation. Separation is the condition where there are one or several independent variables that exactly grouped the categories in binary response. It will result the estimators of MLE method become non-convergent, so that they cannot be used in modeling. One of the effort to resolve the separation is using Firths approach instead. This research has two aims. First, to identify the chance of separation occurrence in binary probit regression model between MLE method and Firths approach. Second, to compare the performance of binary probit regression model estimator that obtained by MLE method and Firths approach using RMSE criteria. Those are performed using simulation method and under different sample size. The results showed that the chance of separation occurrence in MLE method for small sample size is higher than Firths approach. On the other hand, for larger sample size, the probability decreased and relatively identic between MLE method and Firths approach. Meanwhile, Firths estimators have smaller RMSE than MLEs especially for smaller sample sizes. But for larger sample sizes, the RMSEs are not much different. It means that Firths estimators outperformed MLE estimator.

Estimating Total Claim Size in the Auto Insurance Industry: a Comparison between Tweedie and Zero-Adjusted Inverse Gaussian Distribution

Directory of Open Access Journals (Sweden)

Adriana Bruscato Bortoluzzo

2011-01-01

Full Text Available The objective of this article is to estimate insurance claims from an auto dataset using the Tweedie and zero-adjusted inverse Gaussian (ZAIG methods. We identify factors that influence claim size and probability, and compare the results of these methods which both forecast outcomes accurately. Vehicle characteristics like territory, age, origin and type distinctly influence claim size and probability. This distinct impact is not always present in the Tweedie estimated model. Auto insurers should consider estimating total claim size using both the Tweedie and ZAIG methods. This allows for an estimation of confidence interval based on empirical quantiles using bootstrap simulation. Furthermore, the fitted models may be useful in developing a strategy to obtain premium pricing.

New Brunswick Market Design Committee : market design issues paper : choice of market model

International Nuclear Information System (INIS)

2001-01-01

A model for the competitive electricity market in New Brunswick was not specified by the White Paper: New Brunswick Energy Policy, published in March 2001. One of the tasks of the Market Design Committee (MDC) is to select a market model for the province. This report was prepared with this objective in mind. It begins by providing a description of the basic functions that must be performed by any electricity system. Different market models will function differently, and a descriptions of how the functions would be performed under each model is presented. Considering the specific size and geographic location of New Brunswick, a number of actual markets that could be of interest are presented. The various electricity markets normally use one of four market models: vertically integrated monopoly utility, a competitive pool market, a bilateral contract market, and a single-buyer market. The first model was not explained as it represents the existing, non-competitive model whereby the government owns and/or regulates price and investment decision. The case where a market operator receives bids and offers from buyers and sellers and matches them to derive a price and schedule for the spot market is what is called the competitive pool market. When electricity trade takes place through a series of contracts between individual buyers and sellers, it is referred to as a bilateral contract market. Finally, the single-buyer market is defined as a monopoly where the buyer purchases from multiple sellers based on competition amongst them. Different examples are provided of applications of the three markets described in the paper. Both New England and New Zealand were chosen to better illustrate the concepts of a fully competitive pool-based market, as they either have close ties to New Brunswick, or share physical similarities. The single-buyer model is illustrated by the case of Northern Ireland where size is similar. The choices made in Quebec were described in the final

Heterogeneous effects of market integration on subadult body size and nutritional status among the Shuar of Amazonian Ecuador

Science.gov (United States)

Urlacher, Samuel S.; Liebert, Melissa A.; Snodgrass, J. Josh; Blackwell, Aaron D.; Cepon-Robins, Tara J.; Gildner, Theresa E.; Madimenos, Felicia C.; Amir, Dorsa; Bribiescas, Richard G.; Sugiyama, Lawrence S.

2016-01-01

Background Market integration (MI) – increasing production for and consumption from a market-based economy – is drastically altering traditional ways of life and environmental conditions among indigenous Amazonian peoples. The effects of MI on the biology and health of Amazonian children and adolescents, however, remain unclear. Aim This study examines the impact of MI on subadult body size and nutritional status at the population, regional, and household levels among the Shuar of Amazonian Ecuador. Subjects and Methods Anthropometric data were collected between 2005 and 2014 from 2,164 Shuar (age 2-19 years) living in two geographic regions differing in general degree of MI. High-resolution household economic, lifestyle, and dietary data were collected from a subsample of 631 participants. Analyses were performed to investigate relationships between body size and year of data collection, region, and specific aspects of household MI. Results Results from temporal and regional analyses suggest that MI has a significant and overall positive impact on Shuar body size and nutritional status. However, household-level results exhibit nuanced and heterogeneous specific effects of MI underlying these overarching relationships. Conclusion This study provides novel insight into the complex socio-ecological pathways linking MI, physical growth, and health among the Shuar and other indigenous Amazonian populations. PMID:27230632

Market integration and market concentration in horizontally differentiated industries

OpenAIRE

Eckel, Carsten

2001-01-01

This paper derives the impact of market integration on equilibrium firm size and market concentration in horizontally differentiated industries. We show that market concentration (measured by the number of firms) can rise as a consequence of market integration if firms engage in R&D competition. We also demonstrate that whether concentration occurs or not depends on the R&D production function and on consumer preferences. This result implies that the welfare effects of market integration are ...

Estimating the Depth of the Navy Recruiting Market

Science.gov (United States)

2016-09-01

xvi by Potential Rating Index for Zone Improvement Plan Code Markets New Evolution (PRIZM NE) segments and variables based on clustering similar... segment , a total of 66 variables , to the final model. Although NRC does not want to use number of QMA per ZIP code to measure of market potential...9 2. Number of Qualified Military Available by Potential Rating Index for ZIP Code Markets New Evolution Segment Data

Heterogeneous effects of market integration on sub-adult body size and nutritional status among the Shuar of Amazonian Ecuador.

Science.gov (United States)

Urlacher, Samuel S; Liebert, Melissa A; Josh Snodgrass, J; Blackwell, Aaron D; Cepon-Robins, Tara J; Gildner, Theresa E; Madimenos, Felicia C; Amir, Dorsa; Bribiescas, Richard G; Sugiyama, Lawrence S

2016-07-01

Market integration (MI)-increasing production for and consumption from a market-based economy-is drastically altering traditional ways of life and environmental conditions among indigenous Amazonian peoples. The effects of MI on the biology and health of Amazonian children and adolescents, however, remain unclear. This study examines the impact of MI on sub-adult body size and nutritional status at the population, regional and household levels among the Shuar of Amazonian Ecuador. Anthropometric data were collected between 2005-2014 from 2164 Shuar (aged 2-19 years) living in two geographic regions differing in general degree of MI. High-resolution household economic, lifestyle and dietary data were collected from a sub-sample of 631 participants. Analyses were performed to investigate relationships between body size and year of data collection, region and specific aspects of household MI. Results from temporal and regional analyses suggest that MI has a significant and overall positive impact on Shuar body size and nutritional status. However, household-level results exhibit nuanced and heterogeneous specific effects of MI underlying these overarching relationships. This study provides novel insight into the complex socio-ecological pathways linking MI, physical growth and health among the Shuar and other indigenous Amazonian populations.

GUERRILLA MARKETING : A creative marketing method for start-ups

OpenAIRE

Zujewska, Barbara

2014-01-01

The objective of this thesis work was to introduce guerrilla marketing as a valuable marketing method for small and medium size startup companies. The thesis presents the theoretical studies on the subject based on literature and case studies. The practical use of the theory is demonstrated in the marketing plan based on guerrilla marketing approach. The marketing plan was written based on the example of an existing startup company, mCASH. The company is located in Oslo, Norway. The thesis...

Sample size planning for composite reliability coefficients: accuracy in parameter estimation via narrow confidence intervals.

Science.gov (United States)

Terry, Leann; Kelley, Ken

2012-11-01

Composite measures play an important role in psychology and related disciplines. Composite measures almost always have error. Correspondingly, it is important to understand the reliability of the scores from any particular composite measure. However, the point estimates of the reliability of composite measures are fallible and thus all such point estimates should be accompanied by a confidence interval. When confidence intervals are wide, there is much uncertainty in the population value of the reliability coefficient. Given the importance of reporting confidence intervals for estimates of reliability, coupled with the undesirability of wide confidence intervals, we develop methods that allow researchers to plan sample size in order to obtain narrow confidence intervals for population reliability coefficients. We first discuss composite reliability coefficients and then provide a discussion on confidence interval formation for the corresponding population value. Using the accuracy in parameter estimation approach, we develop two methods to obtain accurate estimates of reliability by planning sample size. The first method provides a way to plan sample size so that the expected confidence interval width for the population reliability coefficient is sufficiently narrow. The second method ensures that the confidence interval width will be sufficiently narrow with some desired degree of assurance (e.g., 99% assurance that the 95% confidence interval for the population reliability coefficient will be less than W units wide). The effectiveness of our methods was verified with Monte Carlo simulation studies. We demonstrate how to easily implement the methods with easy-to-use and freely available software. ©2011 The British Psychological Society.

The Cost of Collateralized Borrowing in the Colombian Money Market: Does Connectedness Matter?

OpenAIRE

Constanza Martínez; Carlos León

2014-01-01

Under the view that the market is a weighted and directed network (Barabási, 2003), this document is a first attempt to model the Colombian money market within a spatial econometrics framework. By estimating two standard spatial econometric models, we study the cost of collateralized borrowing (i.e. sell/buy backs) among Colombian financial institutions, and its relationship with the effects induced by traditional variables (leverage, size and borrowing levels), and by spatial variables resul...

Estimating the Open Market Desk's Daily Reaction Function.

OpenAIRE

Feinman, Joshua N

1993-01-01

This paper presents the results of an empirical investigation into the proximate determinants of the Federal Reserve's daily open market operations. Using information available each morning at the Fed conference call, the author models the Open Market Desk's choice of both the quantity and the type of operation, using a friction model for the former and a multinomial logit framework for the latter. Different types of operations are shown to send different signals to the market about the under...

Estimation and control of droplet size and frequency in projected spray mode of a gas metal arc welding (GMAW) process.

Science.gov (United States)

Anzehaee, Mohammad Mousavi; Haeri, Mohammad

2011-07-01

New estimators are designed based on the modified force balance model to estimate the detaching droplet size, detached droplet size, and mean value of droplet detachment frequency in a gas metal arc welding process. The proper droplet size for the process to be in the projected spray transfer mode is determined based on the modified force balance model and the designed estimators. Finally, the droplet size and the melting rate are controlled using two proportional-integral (PI) controllers to achieve high weld quality by retaining the transfer mode and generating appropriate signals as inputs of the weld geometry control loop. Copyright © 2011 ISA. Published by Elsevier Ltd. All rights reserved.

Economics of Swine Marketing in Kafanchan (Katsit)Market, Jama'a ...

African Journals Online (AJOL)

The Gini coefficient was also high (0.53), indicating gross inequality in size distribution and seller concentration, hence oligopoly. Analyses also showed that the market is vertically integrated. Cost of transportation (N100 / animal) was the highest of the marketing services, representing 50.4%. Total cost of marketing ...

Estimates of the Size and Characteristics of the Resident Nonimmigrant Population in the United States: January 2011

Data.gov (United States)

Department of Homeland Security — This report presents estimates of the size and characteristics of the resident nonimmigrant population in the United States. The estimates are daily averages for the...

GONe: Software for estimating effective population size in species with generational overlap

Science.gov (United States)

Coombs, J.A.; Letcher, B.H.; Nislow, K.H.

2012-01-01

GONe is a user-friendly, Windows-based program for estimating effective size (N e) in populations with overlapping generations. It uses the Jorde-Ryman modification to the temporal method to account for age structure in populations. This method requires estimates of age-specific survival and birth rate and allele frequencies measured in two or more consecutive cohorts. Allele frequencies are acquired by reading in genotypic data from files formatted for either GENEPOP or TEMPOFS. For each interval between consecutive cohorts, N e is estimated at each locus and over all loci. Furthermore, N e estimates are output for three different genetic drift estimators (F s, F c and F k). Confidence intervals are derived from a chi-square distribution with degrees of freedom equal to the number of independent alleles. GONe has been validated over a wide range of N e values, and for scenarios where survival and birth rates differ between sexes, sex ratios are unequal and reproductive variances differ. GONe is freely available for download at. ?? 2011 Blackwell Publishing Ltd.

Inbound Marketing - the most important digital marketing strategy

Directory of Open Access Journals (Sweden)

PATRUTIU-BALTES Loredana

2017-01-01

Full Text Available Digital marketing has a major importance in the marketing strategy of any company regardless of sector, size or country of origin. Thus, more than ever, in order to remain competitive, companies are forced to exploit this form of marketing, which essentially can bring huge benefits at low costs. The main form of digital marketing is the inbound marketing, which represents an organic marketing form, based on the close relationship between the company and its prospects or customers, who have expressed their interest in the company’s products voluntarily (based on subscription to newsletters, blog, social networks, etc. and who have been attracted and involved by a high quality of the content marketing.

Estimating Functions of Distributions Defined over Spaces of Unknown Size

Directory of Open Access Journals (Sweden)

David H. Wolpert

2013-10-01

Full Text Available We consider Bayesian estimation of information-theoretic quantities from data, using a Dirichlet prior. Acknowledging the uncertainty of the event space size m and the Dirichlet prior’s concentration parameter c, we treat both as random variables set by a hyperprior. We show that the associated hyperprior, P(c, m, obeys a simple “Irrelevance of Unseen Variables” (IUV desideratum iff P(c, m = P(cP(m. Thus, requiring IUV greatly reduces the number of degrees of freedom of the hyperprior. Some information-theoretic quantities can be expressed multiple ways, in terms of different event spaces, e.g., mutual information. With all hyperpriors (implicitly used in earlier work, different choices of this event space lead to different posterior expected values of these information-theoretic quantities. We show that there is no such dependence on the choice of event space for a hyperprior that obeys IUV. We also derive a result that allows us to exploit IUV to greatly simplify calculations, like the posterior expected mutual information or posterior expected multi-information. We also use computer experiments to favorably compare an IUV-based estimator of entropy to three alternative methods in common use. We end by discussing how seemingly innocuous changes to the formalization of an estimation problem can substantially affect the resultant estimates of posterior expectations.

Use of the superpopulation approach to estimate breeding population size: An example in asynchronously breeding birds

Science.gov (United States)

Williams, K.A.; Frederick, P.C.; Nichols, J.D.

2011-01-01

Many populations of animals are fluid in both space and time, making estimation of numbers difficult. Much attention has been devoted to estimation of bias in detection of animals that are present at the time of survey. However, an equally important problem is estimation of population size when all animals are not present on all survey occasions. Here, we showcase use of the superpopulation approach to capture-recapture modeling for estimating populations where group membership is asynchronous, and where considerable overlap in group membership among sampling occasions may occur. We estimate total population size of long-legged wading bird (Great Egret and White Ibis) breeding colonies from aerial observations of individually identifiable nests at various times in the nesting season. Initiation and termination of nests were analogous to entry and departure from a population. Estimates using the superpopulation approach were 47-382% larger than peak aerial counts of the same colonies. Our results indicate that the use of the superpopulation approach to model nesting asynchrony provides a considerably less biased and more efficient estimate of nesting activity than traditional methods. We suggest that this approach may also be used to derive population estimates in a variety of situations where group membership is fluid. ?? 2011 by the Ecological Society of America.

The Economic Performance and Size of Firms: the Case of Russian Health Resort Market

Directory of Open Access Journals (Sweden)

Nadezda Victorovna Pakhomova

2017-09-01

Full Text Available The article shows how external and internal macro-economic factors (the reduction of real income of the population, the depreciation of the local currency to the US dollar in 2014 -2015, the promotion of Crimea as a direction for health and resort services for Russian citizens impact on the financial and economic indicators of health and resort organizations in Russia during 2012–2015. The calculations based on a variety of Federal Service of State Statistics data demonstrate the positive dynamics of the development of regional markets of health and resort services, due to the regional markets of health and resort services of Krasnodar, Stavropol and Altai regions and due to the inclusion of the Federal District of Crimea within the Russian macroeconomic indicators. The econometric model based on a sample of 272 organizations proves the hypothesis about the more beneficial impact of the changes in macroeconomic factors for large health and resort organizations (with a total annual revenue of 400 million roubles compared with smaller organizations. It is expressed in the growth of sales profitability and annual revenue. The calculations have shown that the organization size as an independent variable in a sample of data related to 2014–2015, increased its positive influence on the dependent variable of annual revenue growth comparing to sampling for 2012–2013. The tough financial constraints in the country trigger the discussion of new opportunities and tools for the development of market conditions, which will stimulate the demand for investment in material and technical base renewal and innovations from the side of large health and resort organizations. In addition to improving the transport accessibility of federal resort regions and measures for promoting and improving the quality of the general health and resort infrastructure, there are discussions to create a favorable competitive environment, improve the public procurement system

Study design and the estimation of the size of key populations at risk of HIV: lessons from Viet Nam.

Science.gov (United States)

Safarnejad, Ali; Groot, Wim; Pavlova, Milena

2018-01-30

Estimation of the size of populations at risk of HIV is a key activity in the surveillance of the HIV epidemic. The existing framework for considering future research needs may provide decision-makers with a basis for a fair process of deciding on the methods of the estimation of the size of key populations at risk of HIV. This study explores the extent to which stakeholders involved with population size estimation agree with this framework, and thus, the study updates the framework. We conducted 16 in-depth interviews with key informants from city and provincial governments, NGOs, research institutes, and the community of people at risk of HIV. Transcripts were analyzed and reviewed for significant statements pertaining to criteria. Variations and agreement around criteria were analyzed, and emerging criteria were validated against the existing framework. Eleven themes emerged which are relevant to the estimation of the size of populations at risk of HIV in Viet Nam. Findings on missing criteria, inclusive participation, community perspectives and conflicting weight and direction of criteria provide insights for an improved framework for the prioritization of population size estimation methods. The findings suggest that the exclusion of community members from decision-making on population size estimation methods in Viet Nam may affect the validity, use, and efficiency of the evidence generated. However, a wider group of decision-makers, including community members among others, may introduce diverse definitions, weight and direction of criteria. Although findings here may not apply to every country with a transitioning economy or to every emerging epidemic, the principles of fair decision-making, value of community participation in decision-making and the expected challenges faced, merit consideration in every situation.

Service marketing

Directory of Open Access Journals (Sweden)

Babić-Hodović Vesna

2002-01-01

Full Text Available Development of postindustrial society and services revolution created numerous changes in size of consumer demand, consumer reaction and priorities. Continuous change on the side of demand and offer must follow changes in marketing orientation. Leader in that change is services marketing which by knowing services range and all the changes builds a new concept called Relationship Marketing.

Estimating organic, local, and other price premiums in the Hawaii fluid milk market.

Science.gov (United States)

Loke, Matthew K; Xu, Xun; Leung, PingSun

2015-04-01

With retail scanner data, we applied hedonic price modeling to explore price premiums for organic, local, and other product attributes of fluid milk in Hawaii. Within the context of revealed preference, this analysis of organic and local attributes, under a single unified framework, is significant, as research in this area is deficient in the existing literature. This paper finds both organic and local attributes delivered price premiums over imported, conventional, whole fluid milk. However, the estimated price premium for organic milk (24.6%) is significantly lower than findings in the existing literature. Likewise, the price premium for the local attribute is estimated at 17.4%, again substantially lower compared with an earlier, stated preference study in Hawaii. Beyond that, we estimated a robust price premium of 19.7% for nutritional benefits claimed. The magnitude of this estimated coefficient reinforces the notion that nutrition information on food is deemed beneficial and valuable. Finally, package size measures the influence of product weight. With each larger package size, the estimate led to a corresponding larger price discount. This result is consistent with the practice of weight discounting that retailers usually offer with fresh packaged food. Additionally, we estimated a fairly high Armington elasticity of substitution, which suggests a relatively high degree of substitution between local and imported fluid milk when their relative price changes. Overall, this study establishes price premiums for organic, local, and nutrition benefits claimed for fluid milk in Hawaii. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Content marketing - the fundamental tool of digital marketing

Directory of Open Access Journals (Sweden)

Loredana PATRUTIU BALTES

2015-12-01

Full Text Available In the era of digitalization, the importance of digital marketing has increased from one year to another as part of the marketing strategy practiced by organizations of any type and any size. Given that digital marketing requires the existence of a content marketing, the success or the failure of the company’s online communication depends to a significant extent on the quality of its content marketing. In this context, besides promoting a high quality of the content marketing, the digital marketers must undertake an analysis of the target in order to adapt their content and to choose the right way of promoting it. This article defines the concept of content marketing and the importance that it has within the marketing policies, as well as the proper means of developing a correct content marketing strategy.

Size and shape of soil humic acids estimated by viscosity and molecular weight.

Science.gov (United States)

Kawahigashi, Masayuki; Sumida, Hiroaki; Yamamoto, Kazuhiko

2005-04-15

Ultrafiltration fractions of three soil humic acids were characterized by viscometry and high performance size-exclusion chromatography (HPSEC) in order to estimate shapes and hydrodynamic sizes. Intrinsic viscosities under given solute/solvent/temperature conditions were obtained by extrapolating the concentration dependence of reduced viscosities to zero concentration. Molecular mass (weight average molecular weight (M (w)) and number average molecular weight (M (n))) and hydrodynamic radius (R(H)) were determined by HPSEC using pullulan as calibrant. Values of M (w) and M (n) ranged from 15 to 118 x 10(3) and from 9 to 50 x 10(3) (g mol(-1)), respectively. Polydispersity, as indicated by M (w)/M (n), increased with increasing filter size from 1.5 to 2.4. The hydrodynamic radii (R(H)) ranged between 2.2 and 6.4 nm. For each humic acid, M (w) and [eta] were related. Mark-Houwink coefficients calculated on the basis of the M (w)-[eta] relationships suggested restricted flexible chains for two of the humic acids and a branched structure for the third humic acid. Those structures probably behave as hydrated sphere colloids in a good solvent. Hydrodynamic radii of fractions calculated from [eta] using Einstein's equation, which is applicable to hydrated sphere colloids, ranged from 2.2 to 7.1 nm. These dimensions are fit to the size of nanospaces on and between clay minerals and micropores in soil particle aggregates. On the other hand, the good agreement of R(H) values obtained by applying Einstein's equation with those directly determined by HPSEC suggests that pullulan is a suitable calibrant for estimation of molecular mass and size of humic acids by HPSEC.

Market structure and market definition: the case of small market banks and thrifts

OpenAIRE

Andrew Cohen

2004-01-01

This paper introduces a simple method to test between two general approaches to defining bank and thrift product markets. I estimate two models that endogenize market structure using data on banks and thrifts from 1,884 rural markets for the year 2000. The first model assumes that banks and thrifts are in "independent product markets," i.e., that bank profitability depends only on competition from other banks and that thrift profitability depends only on competition from other thrifts. An alt...

Body size, skills, and income: evidence from 150,000 teenage siblings.

Science.gov (United States)

Lundborg, Petter; Nystedt, Paul; Rooth, Dan-Olof

2014-10-01

We provide new evidence on the long-run labor market penalty of teenage overweight and obesity using unique and large-scale data on 150,000 male siblings from the Swedish military enlistment. Our empirical analysis provides four important results. First, we provide the first evidence of a large adult male labor market penalty for being overweight or obese as a teenager. Second, we replicate this result using data from the United States and the United Kingdom. Third, we note a strikingly strong within-family relationship between body size and cognitive skills/noncognitive skills. Fourth, a large part of the estimated body-size penalty reflects lower skill acquisition among overweight and obese teenagers. Taken together, these results reinforce the importance of policy combating early-life obesity in order to reduce healthcare expenditures as well as poverty and inequalities later in life.

Estimation of break location and size for loss of coolant accidents using neural networks

International Nuclear Information System (INIS)

Na, Man Gyun; Shin, Sun Ho; Jung, Dong Won; Kim, Soong Pyung; Jeong, Ji Hwan; Lee, Byung Chul

2004-01-01

In this work, a probabilistic neural network (PNN) that has been applied well to the classification problems is used in order to identify the break locations of loss of coolant accidents (LOCA) such as hot-leg, cold-leg and steam generator tubes. Also, a fuzzy neural network (FNN) is designed to estimate the break size. The inputs to PNN and FNN are time-integrated values obtained by integrating measurement signals during a short time interval after reactor scram. An automatic structure constructor for the fuzzy neural network automatically selects the input variables from the time-integrated values of many measured signals, and optimizes the number of rules and its related parameters. It is verified that the proposed algorithm identifies very well the break locations of LOCAs and also, estimate their break size accurately

See food diet? Cultural differences in estimating fullness and intake as a function of plate size.

Science.gov (United States)

Peng, Mei; Adam, Sarah; Hautus, Michael J; Shin, Myoungju; Duizer, Lisa M; Yan, Huiquan

2017-10-01

Previous research has suggested that manipulations of plate size can have a direct impact on perception of food intake, measured by estimated fullness and intake. The present study, involving 570 individuals across Canada, China, Korea, and New Zealand, is the first empirical study to investigate cultural influences on perception of food portion as a function of plate size. The respondents viewed photographs of ten culturally diverse dishes presented on large (27 cm) and small (23 cm) plates, and then rated their estimated usual intake and expected fullness after consuming the dish, using 100-point visual analog scales. The data were analysed with a mixed-model ANCOVA controlling for individual BMI, liking and familiarity of the presented food. The results showed clear cultural differences: (1) manipulations of the plate size had no effect on the expected fullness or the estimated intake of the Chinese and Korean respondents, as opposed to significant effects in Canadians and New Zealanders (p Asian respondents. Overall, these findings, from a cultural perspective, support the notion that estimation of fullness and intake are learned through dining experiences, and highlight the importance of considering eating environments and contexts when assessing individual behaviours relating to food intake. Copyright © 2017 Elsevier Ltd. All rights reserved.

Modelling the PCR amplification process by a size-dependent branching process and estimation of the efficiency

NARCIS (Netherlands)

Lalam, N.; Jacob, C.; Jagers, P.

2004-01-01

We propose a stochastic modelling of the PCR amplification process by a size-dependent branching process starting as a supercritical Bienaymé-Galton-Watson transient phase and then having a saturation near-critical size-dependent phase. This model allows us to estimate the probability of replication

Estimating Effect Sizes and Expected Replication Probabilities from GWAS Summary Statistics

DEFF Research Database (Denmark)

Holland, Dominic; Wang, Yunpeng; Thompson, Wesley K

2016-01-01

Genome-wide Association Studies (GWAS) result in millions of summary statistics ("z-scores") for single nucleotide polymorphism (SNP) associations with phenotypes. These rich datasets afford deep insights into the nature and extent of genetic contributions to complex phenotypes such as psychiatric......-scores, as such knowledge would enhance causal SNP and gene discovery, help elucidate mechanistic pathways, and inform future study design. Here we present a parsimonious methodology for modeling effect sizes and replication probabilities, relying only on summary statistics from GWAS substudies, and a scheme allowing...... for estimating the degree of polygenicity of the phenotype and predicting the proportion of chip heritability explainable by genome-wide significant SNPs in future studies with larger sample sizes. We apply the model to recent GWAS of schizophrenia (N = 82,315) and putamen volume (N = 12,596), with approximately...

Maximum likelihood estimation of finite mixture model for economic data

Science.gov (United States)

Phoong, Seuk-Yen; Ismail, Mohd Tahir

2014-06-01

Finite mixture model is a mixture model with finite-dimension. This models are provides a natural representation of heterogeneity in a finite number of latent classes. In addition, finite mixture models also known as latent class models or unsupervised learning models. Recently, maximum likelihood estimation fitted finite mixture models has greatly drawn statistician's attention. The main reason is because maximum likelihood estimation is a powerful statistical method which provides consistent findings as the sample sizes increases to infinity. Thus, the application of maximum likelihood estimation is used to fit finite mixture model in the present paper in order to explore the relationship between nonlinear economic data. In this paper, a two-component normal mixture model is fitted by maximum likelihood estimation in order to investigate the relationship among stock market price and rubber price for sampled countries. Results described that there is a negative effect among rubber price and stock market price for Malaysia, Thailand, Philippines and Indonesia.

First genome size estimations for some eudicot families and genera

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Garcia, S.

2010-12-01

Full Text Available Genome size diversity in angiosperms varies roughly 2400-fold, although approximately 45% of angiosperm families lack a single genome size estimation, and therefore, this range could be enlarged. To contribute completing family and genera representation, DNA C-Values are here provided for 19 species from 16 eudicot families, including first values for 6 families, 14 genera and 17 species. The sample of species studied is very diverse, including herbs, weeds, vines, shrubs and trees. Data are discussed regarding previous genome size estimates of closely related species or genera, if any, their chromosome number, growth form or invasive behaviour. The present research contributes approximately 1.5% new values for previously unreported angiosperm families, being the current coverage around 55% of angiosperm families, according to the Plant DNA C-Values Database.

La diversidad del tamaño del genoma en angiospermas es muy amplia, siendo el valor más elevado aproximadamente unas 2400 veces superior al más pequeño. Sin embargo, cerca del 45% de las familias no presentan ni una sola estimación, por lo que el rango real podría ser ampliado. Para contribuir a completar la representación de familias y géneros de angiospermas, este estudio contribuye con valores C para 19 especies de 16 familias de eudicoticotiledóneas, incluyendo los primeros valores para 6 familias, 14 géneros y 17 especies. La muestra estudiada es muy diversa, e incluye hierbas, malezas, enredaderas, arbustos y árboles. Se discuten los resultados en función de estimaciones previas del tamaño del genoma de especies o géneros estrechamente relacionados, del número de cromosomas, la forma de crecimiento o el comportamiento invasor de las especies analizadas. El presente estudio contribuye aproximadamente en un 1,5% de nuevos valores para familias de angiospermas no estudiadas previamente, de las que actualmente existe información para el 55%, según la base de datos

Stocking density effects on production characteristics and body composition of market size cobia, Rachycentron canadum, reared in recirculating aquaculture systems

Science.gov (United States)

Production density in excess of a critical threshold can result in a negative relationship between stocking density and fish production. This study was conducted to evaluate production characteristics of juvenile cobia Rachycentron canadum, reared to market size in production-scale recirculating aq...

Growth, characterization and estimation of lattice strain and size in CdS nanoparticles: X-ray peak profile analysis

Science.gov (United States)

Solanki, Rekha Garg; Rajaram, Poolla; Bajpai, P. K.

2018-05-01

This work is based on the growth, characterization and estimation of lattice strain and crystallite size in CdS nanoparticles by X-ray peak profile analysis. The CdS nanoparticles were synthesized by a non-aqueous solvothermal method and were characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), Raman and UV-visible spectroscopy. XRD confirms that the CdS nanoparticles have the hexagonal structure. The Williamson-Hall (W-H) method was used to study the X-ray peak profile analysis. The strain-size plot (SSP) was used to study the individual contributions of crystallite size and lattice strain from the X-rays peaks. The physical parameters such as strain, stress and energy density values were calculated using various models namely, isotropic strain model, anisotropic strain model and uniform deformation energy density model. The particle size was estimated from the TEM images to be in the range of 20-40 nm. The Raman spectrum shows the characteristic optical 1LO and 2LO vibrational modes of CdS. UV-visible absorption studies show that the band gap of the CdS nanoparticles is 2.48 eV. The results show that the crystallite size estimated from Scherrer's formula, W-H plots, SSP and the particle size calculated by TEM images are approximately similar.

Application of Network Scale Up Method in the Estimation of Population Size for Men Who Have Sex with Men in Shanghai, China.

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Jun Wang

Full Text Available Men who have sex with men (MSM are at high risk of HIV infection. For developing proper interventions, it is important to know the size of MSM population. However, size estimation of MSM populations is still a significant public health challenge due to high cost, hard to reach and stigma associated with the population.We aimed to estimate the social network size (c value in general population and the size of MSM population in Shanghai, China by using the net work scale-up method.A multistage random sampling was used to recruit participants aged from 18 to 60 years who had lived in Shanghai for at least 6 months. The "known population method" with adjustment of backward estimation and regression model was applied to estimate the c value. And the MSM population size was further estimated using an adjusted c value taking into account for the transmission effect through social respect level towards MSM.A total of 4017 participants were contacted for an interview, and 3907 participants met the inclusion criterion. The social network size (c value of participants was 236 after adjustment. The estimated size of MSM was 36354 (95% CI: 28489-44219 for the male Shanghaies aged 18 to 60 years, and the proportion of MSM among the total male population aged 18 to 60 years in Shanghai was 0.28%.We employed the network scale-up method and used a wide range of data sources to estimate the size of MSM population in Shanghai, which is useful for HIV prevention and intervention among the target population.

Validation of a food quantification picture book and portion sizes estimation applying perception and memory methods.

Science.gov (United States)

Szenczi-Cseh, J; Horváth, Zs; Ambrus, Á

2017-12-01

We tested the applicability of EPIC-SOFT food picture series used in the context of a Hungarian food consumption survey gathering data for exposure assessment, and investigated errors in food portion estimation resulted from the visual perception and conceptualisation-memory. Sixty-two participants in three age groups (10 to foods. The results were considered acceptable if the relative difference between average estimated and actual weight obtained through the perception method was ≤25%, and the relative standard deviation of the individual weight estimates was food items were rated acceptable. Small portion sizes were tended to be overestimated, large ones were tended to be underestimated. Portions of boiled potato and creamed spinach were all over- and underestimated, respectively. Recalling the portion sizes resulted in overestimation with larger differences (up to 60.7%).

Optimizing CT radiation dose based on patient size and image quality: the size-specific dose estimate method

Energy Technology Data Exchange (ETDEWEB)

Larson, David B. [Stanford University School of Medicine, Department of Radiology, Stanford, CA (United States)

2014-10-15

The principle of ALARA (dose as low as reasonably achievable) calls for dose optimization rather than dose reduction, per se. Optimization of CT radiation dose is accomplished by producing images of acceptable diagnostic image quality using the lowest dose method available. Because it is image quality that constrains the dose, CT dose optimization is primarily a problem of image quality rather than radiation dose. Therefore, the primary focus in CT radiation dose optimization should be on image quality. However, no reliable direct measure of image quality has been developed for routine clinical practice. Until such measures become available, size-specific dose estimates (SSDE) can be used as a reasonable image-quality estimate. The SSDE method of radiation dose optimization for CT abdomen and pelvis consists of plotting SSDE for a sample of examinations as a function of patient size, establishing an SSDE threshold curve based on radiologists' assessment of image quality, and modifying protocols to consistently produce doses that are slightly above the threshold SSDE curve. Challenges in operationalizing CT radiation dose optimization include data gathering and monitoring, managing the complexities of the numerous protocols, scanners and operators, and understanding the relationship of the automated tube current modulation (ATCM) parameters to image quality. Because CT manufacturers currently maintain their ATCM algorithms as secret for proprietary reasons, prospective modeling of SSDE for patient populations is not possible without reverse engineering the ATCM algorithm and, hence, optimization by this method requires a trial-and-error approach. (orig.)

Changes of firm size distribution: The case of Korea

Science.gov (United States)

Kang, Sang Hoon; Jiang, Zhuhua; Cheong, Chongcheul; Yoon, Seong-Min

2011-01-01

In this paper, the distribution and inequality of firm sizes is evaluated for the Korean firms listed on the stock markets. Using the amount of sales, total assets, capital, and the number of employees, respectively, as a proxy for firm sizes, we find that the upper tail of the Korean firm size distribution can be described by power-law distributions rather than lognormal distributions. Then, we estimate the Zipf parameters of the firm sizes and assess the changes in the magnitude of the exponents. The results show that the calculated Zipf exponents over time increased prior to the financial crisis, but decreased after the crisis. This pattern implies that the degree of inequality in Korean firm sizes had severely deepened prior to the crisis, but lessened after the crisis. Overall, the distribution of Korean firm sizes changes over time, and Zipf’s law is not universal but does hold as a special case.

Market potential of small and medium-size nuclear reactors as combined heat and power plants in Europe

International Nuclear Information System (INIS)

Schoen, R.; Hansen, U.; Candeli, R.; Leuchs, D.; Garribba, S.F.; Lefevre, J.C.; Vivante, C.

1987-01-01

A Study has been launched and supported by the Commission of the European Communities to assess the potential market of small and medium size nuclear reactors through EC Countries and to identify those factors which may play a dominant role in this respect. In its first phase, the Study addresses to modular high-temperature gas-cooled reactors that would be installed to produce low-temperature heat and power. Federal Republic of Germany, Italy and France are the countries for which the investigation has been either completed or is under way. The time span of interest is up to the year 2020. Referring to this horizon an appraisal has been made of the number of nuclear units which could come on line to cope with energy demand and their timing. Through the Study a distinction is made between technical potential, economic potential, and effective market potential. It is understood indeed that both economic competitiveness towards other energy sources and institutional or organizational factors may restrict the market which could be covered by this class of nuclear reactors. (author)

Measuring the impact of market coupling on the Italian electricity market

International Nuclear Information System (INIS)

Pellini, Elisabetta

2012-01-01

This paper evaluates the impact on the Italian electricity market of replacing the current explicit auction mechanism with market coupling. Maximising the use of the cross-border interconnection capacity, market coupling increases the level of market integration and facilitates the access to low-cost generation by consumers located in high-cost generation countries. Thus, it is expected that a high-priced area such as Italy could greatly benefit from the introduction of this mechanism. In this paper, the welfare benefits are estimated for 2012 under alternative market scenarios, employing the optimal dispatch model ELFO++. The results of the simulations suggest that the improvement in social surplus is likely to be significant, especially when market fundamentals are tight. - Highlights: ► We study the impact on the Italian electricity market of introducing market coupling. ► We estimate welfare benefits under two market scenarios for 2012. ► Scenarios are simulated using the optimal dispatch model ELFO++. ► Welfare gains range between 33 M€/year and 741 M€/year.

Estimating the size of juvenile fish populations in southeastern coastal-plain estuaries

International Nuclear Information System (INIS)

Kjelson, M.A.

1977-01-01

Understanding the ecological significance of man's activities upon fishery resources requires information on the size of affected fish stocks. The objective of this paper is to provide information to evaluate and plan sampling programs designed to obtain accurate and precise estimates of fish abundance. Nursery habitats, as marsh--tidal creeks and submerged grass beds, offer the optimal conditions for estimating natural mortality rates for young-of-the-year fish in Atlantic and Gulf of Mexico coast estuaries. The area-density method of abundance estimation using quantitative gears is more feasible than either mark-recapture or direct-count techniques. The blockage method provides the most accurate estimates, while encircling devices enable highly mobile species found in open water to be captured. Drop nets and lift nets allow samples to be taken in obstructed sites, but trawls and seines are the most economical gears. Replicate samples are necessary to improve the precision of density estimates, while evaluation and use of gear-catch efficiencies is feasible and required to improve the accuracy of density estimates. Coefficients of variation for replicate trawl samples range from 50 to 150 percent, while catch efficiencies for both trawls and seines for many juvenile fishes range from approximately 30 to 70 percent

Big Data, Computational Science, Economics, Finance, Marketing, Management, and Psychology: Connections

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Chia-Lin Chang

2018-03-01

Full Text Available The paper provides a review of the literature that connects Big Data, Computational Science, Economics, Finance, Marketing, Management, and Psychology, and discusses research issues that are related to the various disciplines. Academics could develop theoretical models and subsequent econometric and statistical models to estimate the parameters in the associated models, as well as conduct simulation to examine whether the estimators in their theories on estimation and hypothesis testing have good size and high power. Thereafter, academics and practitioners could apply theory to analyse some interesting issues in the seven disciplines and cognate areas.

Value Premium and Country Risk as Dimensions to Estimate Conditional Returns: a Study of the Brazilian Market

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Lilian de Castro Medeiros

2015-01-01

Full Text Available Asset pricing is a widely explored theme in the financial literature. Nevertheless, the phenomenon of value premium is still controversial, since although easily detected in developed and emerging markets, little is know about the economic forces that explain its existence. In this context, this article examines value premium in the Brazilian market and investigates the influence of the country risk variable as an additional risk factor for estimating conditional returns in this market not captured by value premium. For that, we employ a five-factor model, formulated by adding the country risk factor to the model of Carhart (1997. We apply the statistical procedure adopted by Fama & French (1993 to the period between 1994 and 2012, with data on nonfinancial companies listed on the BM&FBovespa. The results confirm the existence of value premium in the Brazilian market, and country risk and value premium together are significant factors to explain conditional returns.

Joint inversion of NMR and SIP data to estimate pore size distribution of geomaterials

Science.gov (United States)

Niu, Qifei; Zhang, Chi

2018-03-01

There are growing interests in using geophysical tools to characterize the microstructure of geomaterials because of the non-invasive nature and the applicability in field. In these applications, multiple types of geophysical data sets are usually processed separately, which may be inadequate to constrain the key feature of target variables. Therefore, simultaneous processing of multiple data sets could potentially improve the resolution. In this study, we propose a method to estimate pore size distribution by joint inversion of nuclear magnetic resonance (NMR) T2 relaxation and spectral induced polarization (SIP) spectra. The petrophysical relation between NMR T2 relaxation time and SIP relaxation time is incorporated in a nonlinear least squares problem formulation, which is solved using Gauss-Newton method. The joint inversion scheme is applied to a synthetic sample and a Berea sandstone sample. The jointly estimated pore size distributions are very close to the true model and results from other experimental method. Even when the knowledge of the petrophysical models of the sample is incomplete, the joint inversion can still capture the main features of the pore size distribution of the samples, including the general shape and relative peak positions of the distribution curves. It is also found from the numerical example that the surface relaxivity of the sample could be extracted with the joint inversion of NMR and SIP data if the diffusion coefficient of the ions in the electrical double layer is known. Comparing to individual inversions, the joint inversion could improve the resolution of the estimated pore size distribution because of the addition of extra data sets. The proposed approach might constitute a first step towards a comprehensive joint inversion that can extract the full pore geometry information of a geomaterial from NMR and SIP data.

Sample Size Calculation for Estimating or Testing a Nonzero Squared Multiple Correlation Coefficient

Science.gov (United States)

Krishnamoorthy, K.; Xia, Yanping

2008-01-01

The problems of hypothesis testing and interval estimation of the squared multiple correlation coefficient of a multivariate normal distribution are considered. It is shown that available one-sided tests are uniformly most powerful, and the one-sided confidence intervals are uniformly most accurate. An exact method of calculating sample size to…

Product market integration, tax distortions and public sector size

DEFF Research Database (Denmark)

Andersen, Torben M.; Sørensen, Allan

of product market integration for the public sector are far from straightforward. The reason is gains-from-trade effects which tend to increase the tax base and decrease the opportunity costs of public consumption (marginal utility of private consumption falls). It follows that the retrenchment view...... that product market integration inevitable leads to a downward pressure on public sector activities does not get support in a standard setting. A particularly noteworthy finding is that a country with a large public sector (strong preferences for public consumption) may benefit more by integrating......The implications of product market integration for public sector activities (transfers and public consumption) are considered in a standard setting. The analysis supports that a larger public sector (higher tax rate) tends to increase wages and worsen wage competitiveness. However, the implications...

Effects of insecticide exposure on movement and population size estimates of predatory ground beetles (Coleoptera: Carabidae).

Science.gov (United States)

Prasifka, Jarrad R; Lopez, Miriam D; Hellmich, Richard L; Prasifka, Patricia L

2008-01-01

Estimates of arthropod population size may paradoxically increase following insecticide applications. Research with ground beetles (Coleoptera: Carabidae) suggests that such unusual results reflect increased arthropod movement and capture in traps rather than real changes in population size. However, it is unclear whether direct (hyperactivity) or indirect (prey-mediated) mechanisms produce increased movement. Video tracking of Scarites quadriceps Chaudior indicated that brief exposure to lambda-cyhalothrin or tefluthrin increased total distance moved, maximum velocity and percentage of time moving. Repeated measurements on individual beetles indicated that movement decreased 240 min after initial lambda-cyhalothrin exposure, but increased again following a second exposure, suggesting hyperactivity could lead to increased trap captures in the field. Two field experiments in which ground beetles were collected after lambda-cyhalothrin or permethrin application attempted to detect increases in population size estimates as a result of hyperactivity. Field trials used mark-release-recapture methods in small plots and natural carabid populations in larger plots, but found no significant short-term (<6 day) increases in beetle trap captures. The disagreement between laboratory and field results suggests mechanisms other than hyperactivity may better explain unusual changes in population size estimates. When traps are used as a primary sampling tool, unexpected population-level effects should be interpreted carefully or with additional data less influenced by arthropod activity.

A Mixed-Methods Evaluation of the Choose Less, Weigh Less Portion Size Health Marketing Campaign in Los Angeles County.

Science.gov (United States)

Gase, Lauren N; Barragan, Noel C; Robles, Brenda; Leighs, Michael; Kuo, Tony

2015-01-01

To assess the impact of the Choose Less, Weigh Less portion size health marketing campaign. A mixed-methods, cross-sectional evaluation. A quantitative Internet panel survey was administered through an online sampling vendor and qualitative interviews were conducted by street intercept. The panel survey included 796 participants, weighted to represent Los Angeles County. Street intercept interviews were conducted with 50 other participants. The Choose Less, Weigh Less campaign included print media on transit shelters, bus and rail cars, and billboards; radio and online advertising; and Web site content and social media outreach. The panel survey measured self-reported campaign exposure and outcomes, including knowledge of recommended daily calorie limits, attitudes toward portion sizes, and intent to reduce calories and portion size. Intercept interviews assessed campaign appeal, clarity, and utility. Weighted survey data were analyzed using logistic regression to assess the association between campaign exposure and outcomes. Interview data were analyzed for themes. The campaign reached 19.7% of the Los Angeles County population. Significant differences were seen for 2 of the 10 outcomes assessed. Participants who saw the campaign were more likely than those who did not to report fast-food portion sizes as being too large (adjusted odds ratio [Adj. OR]: 1.89; 95% confidence interval [CI]: 1.16, 3.07) and intention to choose a smaller portion (Adj. OR: 1.99; 95% CI: 1.20, 3.31). Qualitative data revealed three themes about appeal, clarity, and utility. Health marketing efforts targeting portion size can have relatively broad reach and limited but positive impacts on consumer attitudes and intent to select smaller portions.

Highlights of NASA/DOE photovoltaic market assessment visit to Morocco

Science.gov (United States)

1981-01-01

A broad range of agricultural, rural development, and other power applications in various regions of Morocco were examined to determine the potential market for photovoltaic products in Moroccan development. The primary focus of the study was the agriculture sector which accounts for approximately 17% of the country's GNP. The country has a clear need for reliable remote power systems, but does not have the financial resources to invest in the relatively high capital cost PV equipment. A modest potential for PV use was identified in nonagricultural rural services, such as refrigerators for rural clinics and rural radio-telephones. The main potential for PV in Morocco in the next five years lies mainly in the telecommunications sector. Applications include rural TV sets, TV repeater stations, microwave relay stations, and railroad, marine, and airline signalling. Market size estimates were derived from development and expansion plans. At an average customer cost for complete installed systems from $18/Wp to $30/Wp the total potential market value is estimated in the range of $6.6 to $11 million over the 1981-1986 period.

A simple nomogram for sample size for estimating sensitivity and specificity of medical tests

Directory of Open Access Journals (Sweden)

Malhotra Rajeev

2010-01-01

Full Text Available Sensitivity and specificity measure inherent validity of a diagnostic test against a gold standard. Researchers develop new diagnostic methods to reduce the cost, risk, invasiveness, and time. Adequate sample size is a must to precisely estimate the validity of a diagnostic test. In practice, researchers generally decide about the sample size arbitrarily either at their convenience, or from the previous literature. We have devised a simple nomogram that yields statistically valid sample size for anticipated sensitivity or anticipated specificity. MS Excel version 2007 was used to derive the values required to plot the nomogram using varying absolute precision, known prevalence of disease, and 95% confidence level using the formula already available in the literature. The nomogram plot was obtained by suitably arranging the lines and distances to conform to this formula. This nomogram could be easily used to determine the sample size for estimating the sensitivity or specificity of a diagnostic test with required precision and 95% confidence level. Sample size at 90% and 99% confidence level, respectively, can also be obtained by just multiplying 0.70 and 1.75 with the number obtained for the 95% confidence level. A nomogram instantly provides the required number of subjects by just moving the ruler and can be repeatedly used without redoing the calculations. This can also be applied for reverse calculations. This nomogram is not applicable for testing of the hypothesis set-up and is applicable only when both diagnostic test and gold standard results have a dichotomous category.

Volatility transmission and volatility impulse response functions in European electricity forward markets

International Nuclear Information System (INIS)

Le Pen, Yannick; Sevi, Benoit

2008-01-01

Using daily data from March 2001 to June 2005, we estimate a VAR-BEKK model and find evidence of return and volatility spillovers between the German, the Dutch and the British forward electricity markets. We apply Hafner and Herwartz [2006, Journal of International Money and Finance 25, 719-740] Volatility Impulse Response Function(VIRF) to quantify the impact of shock on expected conditional volatility. We observe that a shock has a high positive impact only if its size is large compared to the current level of volatility. The impact of shocks are usually not persistent, which may be an indication of market efficiency. Finally, we estimate the density of the VIRF at different forecast horizon. These fitted distributions are asymmetric and show that extreme events are possible even if their probability is low. These results have interesting implications for market participants whose risk management policy is based on option prices which themselves depend on the volatility level. (authors)

On the evaluation of market power and market dominance-The Nordic electricity market

International Nuclear Information System (INIS)

Hellmer, Stefan; Warell, Linda

2009-01-01

This paper studies different concentration and dominance measures using structural indexes used to initially screen the competitive situation in a market. The Nordic and Swedish electricity markets are used as the empirical cases. Market concentration issues in the Nordic electricity market in general and in Sweden in particular have been, at least in initial screenings, approached by the Herfindahl-Hirschman Index (HHI). This article uses an alternative measure to HHI, which is based on market shares of the two largest firms in the market. The results shows that only the Swedish wholesale market has a firm that can be regarded as dominant, but only during very short periods. The results from a hypothetical merger between the second and third largest company in the Swedish wholesale market shows that when the dominant position of the largest firm is reduced, by increasing the size of the second largest firm, the threshold value indicates that competition actually will increase (contradicting to the HHI).

FAVAR Analysis of Foreign Investment with Capital Market Predictors: Evidence on Nigerian and Selected African Stock Exchanges

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David Umoru

2018-03-01

Full Text Available Econometrically, we analyzed role of selected African stock exchanges in welcoming FDI inflows by estimating time-varying factor augmented vector auto-regression (FAVAR model for 2006:Q1 to 2017:Q4. Our results support FDI being massively influenced by movements in two stock market predictors namely, stock market's size, that is, total market value of stock market's listed shares calculated by multiplying a stock market’s shares listed by current market price of one share and stock market liquidity which is total value of traded shares relative to the size of the economy. By empirical inference, African stock exchanges exhibit inordinate turnover ratio and so these markets are exceedingly liquid. Particularly, transactions at stock exchange are significant indicators for foreign investors and total market value of listed shares in stock markets is linked positively with FDI inflow into Africa. The empirical finding is that viable African stock exchanges are attractive indicator of market concentration and high investment profile in Africa. The study so remarked the requisite to advance the stock exchange in order to boost funds accumulation for investment drive. Also, African governments should project and implement stock market-friendly procedures acceptable to maximize welfares of spillover effects of FDI.

Estimating the production, consumption and export of cannabis: The Dutch case.

Science.gov (United States)

van der Giessen, Mark; van Ooyen-Houben, Marianne M J; Moolenaar, Debora E G

2016-05-01

Quantifying an illegal phenomenon like a drug market is inherently complex due to its hidden nature and the limited availability of reliable information. This article presents findings from a recent estimate of the production, consumption and export of Dutch cannabis and discusses the opportunities provided by, and limitations of, mathematical models for estimating the illegal cannabis market. The data collection consisted of a comprehensive literature study, secondary analyses on data from available registrations (2012-2014) and previous studies, and expert opinion. The cannabis market was quantified with several mathematical models. The data analysis included a Monte Carlo simulation to come to a 95% interval estimate (IE) and a sensitivity analysis to identify the most influential indicators. The annual production of Dutch cannabis was estimated to be between 171 and 965tons (95% IE of 271-613tons). The consumption was estimated to be between 28 and 119tons, depending on the inclusion or exclusion of non-residents (95% IE of 51-78tons or 32-49tons respectively). The export was estimated to be between 53 and 937tons (95% IE of 206-549tons or 231-573tons, respectively). Mathematical models are valuable tools for the systematic assessment of the size of illegal markets and determining the uncertainty inherent in the estimates. The estimates required the use of many assumptions and the availability of reliable indicators was limited. This uncertainty is reflected in the wide ranges of the estimates. The estimates are sensitive to 10 of the 45 indicators. These 10 account for 86-93% of the variation found. Further research should focus on improving the variables and the independence of the mathematical models. Copyright © 2016 Elsevier B.V. All rights reserved.

Bias Corrections for Standardized Effect Size Estimates Used with Single-Subject Experimental Designs

Science.gov (United States)

Ugille, Maaike; Moeyaert, Mariola; Beretvas, S. Natasha; Ferron, John M.; Van den Noortgate, Wim

2014-01-01

A multilevel meta-analysis can combine the results of several single-subject experimental design studies. However, the estimated effects are biased if the effect sizes are standardized and the number of measurement occasions is small. In this study, the authors investigated 4 approaches to correct for this bias. First, the standardized effect…

Estimation of effective population size in continuously distributed populations: There goes the neighborhood

Science.gov (United States)

M. C. Neel; K. McKelvey; N. Ryman; M. W. Lloyd; R. Short Bull; F. W. Allendorf; M. K. Schwartz; R. S. Waples

2013-01-01

Use of genetic methods to estimate effective population size (Ne) is rapidly increasing, but all approaches make simplifying assumptions unlikely to be met in real populations. In particular, all assume a single, unstructured population, and none has been evaluated for use with continuously distributed species. We simulated continuous populations with local mating...

Sample size estimation to substantiate freedom from disease for clustered binary data with a specific risk profile

DEFF Research Database (Denmark)

Kostoulas, P.; Nielsen, Søren Saxmose; Browne, W. J.

2013-01-01

and power when applied to these groups. We propose the use of the variance partition coefficient (VPC), which measures the clustering of infection/disease for individuals with a common risk profile. Sample size estimates are obtained separately for those groups that exhibit markedly different heterogeneity......, thus, optimizing resource allocation. A VPC-based predictive simulation method for sample size estimation to substantiate freedom from disease is presented. To illustrate the benefits of the proposed approach we give two examples with the analysis of data from a risk factor study on Mycobacterium avium...

Measuring the Impact of Road Rehabilitation on Spatial Market Efficiency in Maize Markets in Mozambique

DEFF Research Database (Denmark)

Cirera, Xavier; Arndt, Channing

2008-01-01

to the existing literature in three ways. First, a unique data set, where road rehabilitation episodes between market pairs are identified, is developed. Second, special care is devoted to estimation of transaction costs due to the sensitivity of the PBM model to the quality of transaction costs estimates......This article analyzes the impact of road rehabilitation on the spatial market efficiency of maize markets in Mozambique. We estimate a modified version of the Parity Bounds Model (PBM) that allows us to test the impact of road rehabilitation on spatial efficiency. This article seeks to contribute....... Finally, as opposed to most existing literature that focuses on relatively distant markets, the article focuses on spatially closed markets. We find that maize markets tend to be segmented due to high transport costs. Following road rehabilitation, inefficiency and average absolute price differentials...

An empirical typology of energy services based on a well-developed market: France

International Nuclear Information System (INIS)

Duplessis, Bruno; Adnot, Jérôme; Dupont, Maxime; Racapé, François

2012-01-01

The investigation is an attempt to apply a set of consistent and official definitions of energy services (ES), energy efficiency services (EES) and energy performance contracting (EPC) on a well-developed market: France. After defining the historical context of the French market the authors describe the types of offers that are presently made and that fall within the definition of energy services. There are many classic and novel factors for the success of energy services. For instance, the energy services market is now partly structured by the CEE scheme, the French ‘white certificates’ or ‘energy certificates scheme’. Also the grid problems lead to new services. The companies active on the market are described as a result of an empirical survey of ES market in France. This empirical survey of ES market in France includes estimates of the number of companies and of their turnover both for ES and EES. Examples and case studies are developed as a background. - Highlights: ► We apply a consistent and official set of definitions of energy services (ES). ► French ES market is structured by historical ES and shaped by recent evolutions. ► French ES market is now partly structured by white certificates and grid management. ► We describe the companies active on French market through an empirical survey. ► We have estimated French market size (actors and turnover) both for ES and EES.

Body Size Estimation from Early to Middle Childhood: Stability of Underestimation, BMI, and Gender Effects

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Silje Steinsbekk

2017-11-01

Full Text Available Individuals who are overweight are more likely to underestimate their body size than those who are normal weight, and overweight underestimators are less likely to engage in weight loss efforts. Underestimation of body size might represent a barrier to prevention and treatment of overweight; thus insight in how underestimation of body size develops and tracks through the childhood years is needed. The aim of the present study was therefore to examine stability in children’s underestimation of body size, exploring predictors of underestimation over time. The prospective path from underestimation to BMI was also tested. In a Norwegian cohort of 6 year olds, followed up at ages 8 and 10 (analysis sample: n = 793 body size estimation was captured by the Children’s Body Image Scale, height and weight were measured and BMI calculated. Overall, children were more likely to underestimate than overestimate their body size. Individual stability in underestimation was modest, but significant. Higher BMI predicted future underestimation, even when previous underestimation was adjusted for, but there was no evidence for the opposite direction of influence. Boys were more likely than girls to underestimate their body size at ages 8 and 10 (age 8: 38.0% vs. 24.1%; Age 10: 57.9% vs. 30.8% and showed a steeper increase in underestimation with age compared to girls. In conclusion, the majority of 6, 8, and 10-year olds correctly estimate their body size (prevalence ranging from 40 to 70% depending on age and gender, although a substantial portion perceived themselves to be thinner than they actually were. Higher BMI forecasted future underestimation, but underestimation did not increase the risk for excessive weight gain in middle childhood.

Unit size limitations in smaller power systems

International Nuclear Information System (INIS)

McConnach, J.S.

1975-01-01

The developing nations have generally found it an economic necessity to accept the minimum commercial size limit of 600 MWe. Smaller reactor sizes tendered as 'one off' specials carry high specific cost penalties which considerably weaken the competitiveness of nuclear versus conventional thermal plants. The revised IAEA market survey for nuclear power in developing countries (1974 edition) which takes account of the recent heavy escalation in oil prices, indicates a reasonable market for smaller size reactors in the range 150 MWe to 400 MWe, but until this market is approached seriously by manufacturers, the commercial availability and economic viability of smaller size reactors remains uncertain. (orig.) [de

How accurate are adolescents in portion-size estimation using the computer tool young adolescents' nutrition assessment on computer (YANA-C)?

OpenAIRE

Vereecken, Carine; Dohogne, Sophie; Covents, Marc; Maes, Lea

2010-01-01

Computer-administered questionnaires have received increased attention for large-scale population research on nutrition. In Belgium-Flanders, Young Adolescents' Nutrition Assessment on Computer (YANA-C) has been developed. In this tool, standardised photographs are available to assist in portion-size estimation. The purpose of the present study is to assess how accurate adolescents are in estimating portion sizes of food using YANA-C. A convenience sample, aged 11-17 years, estimated the amou...

Interpreting surveys to estimate the size of the monarch butterfly population: Pitfalls and prospects.

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John M Pleasants

Full Text Available To assess the change in the size of the eastern North American monarch butterfly summer population, studies have used long-term data sets of counts of adult butterflies or eggs per milkweed stem. Despite the observed decline in the monarch population as measured at overwintering sites in Mexico, these studies found no decline in summer counts in the Midwest, the core of the summer breeding range, leading to a suggestion that the cause of the monarch population decline is not the loss of Midwest agricultural milkweeds but increased mortality during the fall migration. Using these counts to estimate population size, however, does not account for the shift of monarch activity from agricultural fields to non-agricultural sites over the past 20 years, as a result of the loss of agricultural milkweeds due to the near-ubiquitous use of glyphosate herbicides. We present the counter-hypotheses that the proportion of the monarch population present in non-agricultural habitats, where counts are made, has increased and that counts reflect both population size and the proportion of the population observed. We use data on the historical change in the proportion of milkweeds, and thus monarch activity, in agricultural fields and non-agricultural habitats to show why using counts can produce misleading conclusions about population size. We then separate out the shifting proportion effect from the counts to estimate the population size and show that these corrected summer monarch counts show a decline over time and are correlated with the size of the overwintering population. In addition, we present evidence against the hypothesis of increased mortality during migration. The milkweed limitation hypothesis for monarch decline remains supported and conservation efforts focusing on adding milkweeds to the landscape in the summer breeding region have a sound scientific basis.

Potential Size of and Value Proposition for H2@Scale Concept

Energy Technology Data Exchange (ETDEWEB)

Ruth, Mark F [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Jadun, Paige [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Pivovar, Bryan S [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Elgowainy, Amgad [Argonne National Laboratory

2017-11-09

The H2@Scale concept is focused on developing hydrogen as an energy carrier and using hydrogen's properties to improve the national energy system. Specifically hydrogen has the abilities to (1) supply a clean energy source for industry and transportation and (2) increase the profitability of variable renewable electricity generators such as wind turbines and solar photovoltaic (PV) farms by providing value for otherwise potentially-curtailed electricity. Thus the concept also has the potential to reduce oil dependency by providing a low-carbon fuel for fuel cell electric vehicles (FCEVs), reduce emissions of carbon dioxide and pollutants such as NOx, and support domestic energy production, manufacturing, and U.S. economic competitiveness. The analysis reported here focuses on the potential market size and value proposition for the H2@Scale concept. It involves three analysis phases: 1. Initial phase estimating the technical potential for hydrogen markets and the resources required to meet them; 2. National-scale analysis of the economic potential for hydrogen and the interactions between willingness to pay by hydrogen users and the cost to produce hydrogen from various sources; and 3. In-depth analysis of spatial and economic issues impacting hydrogen production and utilization and the markets. Preliminary analysis of the technical potential indicates that the technical potential for hydrogen use is approximately 60 million metric tons (MMT) annually for light duty FCEVs, heavy duty vehicles, ammonia production, oil refining, biofuel hydrotreating, metals refining, and injection into the natural gas system. The technical potential of utility-scale PV and wind generation independently are much greater than that necessary to produce 60 MMT / year hydrogen. Uranium, natural gas, and coal reserves are each sufficient to produce 60 MMT / year hydrogen in addition to their current uses for decades to centuries. National estimates of the economic potential of

Food photographs in nutritional surveillance: errors in portion size estimation using drawings of bread and photographs of margarine and beverages consumption.

Science.gov (United States)

De Keyzer, Willem; Huybrechts, Inge; De Maeyer, Mieke; Ocké, Marga; Slimani, Nadia; van 't Veer, Pieter; De Henauw, Stefaan

2011-04-01

Food photographs are widely used as instruments to estimate portion sizes of consumed foods. Several food atlases are available, all developed to be used in a specific context and for a given study population. Frequently, food photographs are adopted for use in other studies with a different context or another study population. In the present study, errors in portion size estimation of bread, margarine on bread and beverages by two-dimensional models used in the context of a Belgian food consumption survey are investigated. A sample of 111 men and women (age 45-65 years) were invited for breakfast; two test groups were created. One group was asked to estimate portion sizes of consumed foods using photographs 1-2 d after consumption, and a second group was asked the same after 4 d. Also, real-time assessment of portion sizes using photographs was performed. At the group level, large overestimation of margarine, acceptable underestimation of bread and only small estimation errors for beverages were found. Women tended to have smaller estimation errors for bread and margarine compared with men, while the opposite was found for beverages. Surprisingly, no major difference in estimation error was found after 4 d compared with 1-2 d. Individual estimation errors were large for all foods. The results from the present study suggest that the use of food photographs for portion size estimation of bread and beverages is acceptable for use in nutrition surveys. For photographs of margarine on bread, further validation using smaller amounts corresponding to actual consumption is recommended.

The Potential of the Market for the Kyoto Mechanisms

International Nuclear Information System (INIS)

Zhang, Z.X.

2000-01-01

The Kyoto Protocol is the first international environmental agreement to set legally binding greenhouse gas (GHG) emissions targets and timetables for Annex I countries. It incorporates emissions trading and two project-based flexibility mechanisms, namely joint implementation (JI) and the clean development mechanism (CDM) to help Annex I countries to meet their Kyoto targets at a lower overall cost. The extent to which their compliance cost can be lowered depends on the size of the market for all three flexibility mechanisms under the Protocol. This article estimates the size of such a market and demonstrates that restrictions on the use of flexibility mechanisms not only reduce potential of the Annex I countries' efficiency gains, but are furthermore not beneficial to developing countries since they restrict the total financial flows to developing countries under the CDM. Thus, from the perspective of husbanding the world's limited resources, the fewer the restrictions on the use of flexibility mechanisms, the greater are the gains from their use

Laser photogrammetry improves size and demographic estimates for whale sharks

Science.gov (United States)

Richardson, Anthony J.; Prebble, Clare E.M.; Marshall, Andrea D.; Bennett, Michael B.; Weeks, Scarla J.; Cliff, Geremy; Wintner, Sabine P.; Pierce, Simon J.

2015-01-01

Whale sharks Rhincodon typus are globally threatened, but a lack of biological and demographic information hampers an accurate assessment of their vulnerability to further decline or capacity to recover. We used laser photogrammetry at two aggregation sites to obtain more accurate size estimates of free-swimming whale sharks compared to visual estimates, allowing improved estimates of biological parameters. Individual whale sharks ranged from 432–917 cm total length (TL) (mean ± SD = 673 ± 118.8 cm, N = 122) in southern Mozambique and from 420–990 cm TL (mean ± SD = 641 ± 133 cm, N = 46) in Tanzania. By combining measurements of stranded individuals with photogrammetry measurements of free-swimming sharks, we calculated length at 50% maturity for males in Mozambique at 916 cm TL. Repeat measurements of individual whale sharks measured over periods from 347–1,068 days yielded implausible growth rates, suggesting that the growth increment over this period was not large enough to be detected using laser photogrammetry, and that the method is best applied to estimating growth rates over longer (decadal) time periods. The sex ratio of both populations was biased towards males (74% in Mozambique, 89% in Tanzania), the majority of which were immature (98% in Mozambique, 94% in Tanzania). The population structure for these two aggregations was similar to most other documented whale shark aggregations around the world. Information on small (sharks, mature individuals, and females in this region is lacking, but necessary to inform conservation initiatives for this globally threatened species. PMID:25870776

Has the 2008 financial crisis affected stock market efficiency? The case of Eurozone

Science.gov (United States)

Anagnostidis, P.; Varsakelis, C.; Emmanouilides, C. J.

2016-04-01

In this paper, the impact of the 2008 financial crisis on the weak-form efficiency of twelve Eurozone stock markets is investigated empirically. Efficiency is tested via the Generalized Hurst Exponent method, while dynamic Hurst exponents are estimated by means of the rolling window technique. To account for biases associated with the finite sample size and the leptokurtosis of the financial data, the statistical significance of the Hurst exponent estimates is assessed through a series of Monte-Carlo simulations drawn from the class of α-stable distributions. According to our results, the 2008 crisis has adversely affected stock price efficiency in most of the Eurozone capital markets, leading to the emergence of significant mean-reverting patterns in stock price movements.

SpotCaliper: fast wavelet-based spot detection with accurate size estimation.

Science.gov (United States)

Püspöki, Zsuzsanna; Sage, Daniel; Ward, John Paul; Unser, Michael

2016-04-15

SpotCaliper is a novel wavelet-based image-analysis software providing a fast automatic detection scheme for circular patterns (spots), combined with the precise estimation of their size. It is implemented as an ImageJ plugin with a friendly user interface. The user is allowed to edit the results by modifying the measurements (in a semi-automated way), extract data for further analysis. The fine tuning of the detections includes the possibility of adjusting or removing the original detections, as well as adding further spots. The main advantage of the software is its ability to capture the size of spots in a fast and accurate way. http://bigwww.epfl.ch/algorithms/spotcaliper/ zsuzsanna.puspoki@epfl.ch Supplementary data are available at Bioinformatics online. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

THE ESTIMATION OF INFLUENCE OF OUT-OF-BALANCE INTANGIBLE ASSETS ON THE ENTERPRISE MARKET VALUE

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Y. Melnyk

2017-12-01

Full Text Available The aim of this article is investigation of the factors of influence of out-of-balance intangible assetsand other non-monetary factors on the general market value of the enterprises of small, middle-sized and bigbusiness with the aim of providing their competitiveness, further development and giving the possibility ofmanaging the enterprise cost in the market. The investigation showed that the degree of influence of the latent non-monetary factors, including out-of-balance intangible assets can be much more essential than influence of balance intangible assets and other assets of the enterprise. Carrying out of the investigation allowed us to determine optimal methodological approaches y of determining the enterprise cost taking intoaccount out-of-balance intangible assets. The methodology has a number of indisputable advantages, whichcan be leveled only during carrying out the further investigations.

MARKET DECISION PREFERENCES OF DAIRY FARMERS TOWARDS TRADITIONAL AND MODERN CHANNELS OF MILK MARKETING: AN EVIDENCE FROM PUNJAB PROVINCE OF PAKISTAN

Directory of Open Access Journals (Sweden)

Mazhir Nadeem Ishaq

2017-07-01

Full Text Available This study was specifically conducted in the four districts of Punjab province of Pakistan. The principal objective was to identify major explanatory variables that might influence dairy farmers’ market participation decisions regarding the selection of traditional and modern channels of milk marketing. Data was collected from field survey and the sample size comprised of 320 dairy farmers, randomly selected from study area. Multinomial logit model was used an econometric tool to estimate the impacts of fourteen independent variables on the dependent variable (selection of milk marketing channel. Model results showed that eight factors like gender, old aged farmers, long distance between dairy farm and urban market, easy milk selling at door step, advance cash payment, lack of quality inspection, strong social relationship with milk collectors, and better milk price were important predictors influencing milk producers to choose traditional channels for the sale of their milk produce. Impacts of these variables were significant at 5% of significance level except long distance which was significant at 1%. Conversely to this, fourfactors such as high education level of dairy farmers, large herd size, provision of extension services, and purchase of evening milk were motivating dairy farmers to sell milk through modern channels. Traditional milk channels were preferred by majority of milk producers but these channels were lacking in delivering the quality milk to consumers. Policy implication for sustainable milk marketing might be the provision of dairy advisory services, advance payment framework, improving logistic infrastructure, and enforcement of milk quality inspection could ensure milk safety along sustainable milk supply.

U.S. Energy Service Company Industry: Market Size and Project Performance from 1990-2008

Energy Technology Data Exchange (ETDEWEB)

Larsen, Peter; Goldman, Charles; Satchwell, Andrew

2012-08-21

The U.S. energy service company (ESCO) industry is an example of a private sector business model where energy savings are delivered to customers primarily through the use of performance-based contracts. This study was conceived as a snapshot of the ESCO industry prior to the economic slowdown and the introduction of federal stimulus funding mandated by enactment of the American Recovery and Reinvestment Act of 2009 (ARRA). This study utilizes two parallel analytic approaches to characterize ESCO industry and market trends in the U.S.: (1) a ?top-down? approach involving a survey of individual ESCOs to estimate aggregate industry activity and (2) a ?bottom-up? analysis of a database of ~;;3,250 projects (representing over $8B in project investment) that reports market trends including installed EE retrofit strategies, project installation costs and savings, project payback times, and benefit-cost ratios over time. Despite the onset of a severe economic recession, the U.S. ESCO industry managed to grow at about 7percent per year between 2006 and 2008. ESCO industry revenues were about $4.1 billion in 2008 and ESCOs anticipate accelerated growth through 2011 (25percent per year). We found that 2,484 ESCO projects in our database generated ~;;$4.0 billion ($2009) in net, direct economic benefits to their customers. We estimate that the ESCO project database includes about 20percent of all U.S. ESCO market activity from 1990-2008. Assuming the net benefits per project are comparable for ESCO projects that are not included in the LBNL database, this would suggest that the ESCO industry has generated ~;;$23 billion in net direct economic benefits for customers at projects installed between 1990 and 2008. There is empirical evidence confirming that the industry is evolving by installing more comprehensive and complex measures?including onsite generation and measures to address deferred maintenance?but this evolution has significant implications for customer project

Estimating Stocks Return with Decomposition of the Book-to-Market Ratio: Evidences from Bovespa

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Juliano Ribeiro de Almeida

2010-12-01

Full Text Available The book-to-market (BM ratio differs across stocks because to differences in expected cashflows and expected returns. The central hypothesis is that the evolution of BM, in terms of past changes in price and book equity, contains information about future cashflows that can be used to improve estimates of expected returns. This article used a database of Economática to extract a sample of non-financial companies shares listed on BOVESPA and test this hypothesis. The estimated regressions were performed monthly during the period July 1996 to June 2008. Both for large and mid caps as for small caps, the results do not favor this hypothesis and show that only the most recent BM is important to predict the assets returns. Furthermore, stock issues and repurchases are also related to future cashflows and it is expected to improve estimates of expected returns. However, the results provide no evidence favoring that.

RELATIONSHIP DERIVATIVES FINANCIAL MARKETS, MONEY AND STOCK MARKETS AS A SUBSYSTEM OF FINANCIAL MARKET

OpenAIRE

Yulia Yelnikova

2016-01-01

Under conditions of intensive strengthening of globalization of world financial markets and deepening of the crisis, the main source of which are financial markets, financial derivatives market is rapidly developing. In such circumstances, we observe very active growing demand for tools, the main purpose of which is to reduce the financial risk – derivatives. Outlined trend has also involved Ukraine. In this connection, there is an objective need to develop estimate the interconnection of the...

Quantitative testing of the methodology for genome size estimation in plants using flow cytometry: a case study of the Primulina genus

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Jing eWang

2015-05-01

Full Text Available Flow cytometry (FCM is a commonly used method for estimating genome size in many organisms. The use of flow cytometry in plants is influenced by endogenous fluorescence inhibitors and may cause an inaccurate estimation of genome size; thus, falsifying the relationship between genome size and phenotypic traits/ecological performance. Quantitative optimization of FCM methodology minimizes such errors, yet there are few studies detailing this methodology. We selected the genus Primulina, one of the most representative and diverse genera of the Old World Gesneriaceae, to evaluate the methodology effect on determining genome size. Our results showed that buffer choice significantly affected genome size estimation in six out of the eight species examined and altered the 2C-value (DNA content by as much as 21.4%. The staining duration and propidium iodide (PI concentration slightly affected the 2C-value. Our experiments showed better histogram quality when the samples were stained for 40 minutes at a PI concentration of 100 µg ml-1. The quality of the estimates was not improved by one-day incubation in the dark at 4 °C or by centrifugation. Thus, our study determined an optimum protocol for genome size measurement in Primulina: LB01 buffer supplemented with 100 µg ml-1 PI and stained for 40 minutes. This protocol also demonstrated a high universality in other Gesneriaceae genera. We report the genome size of nine Gesneriaceae species for the first time. The results showed substantial genome size variation both within and among the species, with the 2C-value ranging between 1.62 and 2.71 pg. Our study highlights the necessity of optimizing the FCM methodology prior to obtaining reliable genome size estimates in a given taxon.

Direct marketing

Directory of Open Access Journals (Sweden)

Čičić Muris

2002-01-01

Full Text Available Direct Marketing (DM is usually treated as unworthy activity, with actions at the edge of legality and activities minded cheating. Despite obvious problems regarding ethics and privacy threat, DM with its size, importance and role in a concept of integrated marketing communication deserves respect and sufficient analysis and review

Micro Mobility Marketing

DEFF Research Database (Denmark)

Hosbond, Jens Henrik; Skov, Mikael B.

2008-01-01

, in our case a medium-sized retail supermarket. Two prototypes based on push and pull marketing strategies are implemented and evaluated. Taking outset in a synthesis of central issues in contemporary research on mobile marketing, we discuss their role in micro mobility marketing to point to similarities......Mobile marketing refers to marketing of services or goods using mobile technology and mobile marketing holds potentially great economical opportunities. Traditionally, mobile marketing has been viewed as mobility in the large taking place virtually anywhere, anytime. Further, research shows...... considerable number of studies on push-based SMS mobile marketing campaigns. This paper explores a related yet different form of mobile marketing namely micro mobility marketing. Micro mobility marketing denotes mobility in the small, meaning that promotion of goods takes place within a circumscribed location...

Market potential of small and medium-size nuclear reactors as combined heat and power plants in Europe

International Nuclear Information System (INIS)

Candeli, R.; Leuchs, D.; Garribba, S.F.; Hansen, U.; Lefevre, J.C.; Schoen, R.; Vivante, C.

1988-01-01

The preliminary results are presented concerning a study launched by the Commission of the European Communities to assess the potential market of small and medium-size nuclear reactors through EC member countries. The study was aimed at identifying those factors that may have a role in shaping the eventual deployment and diffusion of this class of nuclear reactors. In a first phase, attention focused on modular high-temperature gas-cooled reactors that would be installed to produce low-temperature heat and power. Federal Republic of Germany, Italy and France are the countries for which the investigation has been completed. The time span of interest is up to the year 2020. Referring to this horizon, an appraisal has been made of the number of nuclear units which could come on line to cope with energy demand and their timing. Through the study a distinction is made between technical potential, economic potential, and effective market potential. It is understood indeed that both economic competitiveness towards other energy sources and also institutional or organizational factors may restrict the market which could become accessible and would be covered by the new nuclear plants. (orig.)

Understanding Emerging Market Sovereign Bond Yield Spread: Role of Default and Non-Default Determinants

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Adelia Surya Pratiwi

2015-04-01

Full Text Available This paper is motivated by the fact that emerging market assets size has been expanding and trying to use sovereign debt market as part of capital market as main research focus. It is highlighting the distinction between default and non-default determinants and examining their significance in explaining emerging market sovereign bond yield spread. Using Cross-Sectional Fixed-Effect Panel Estimator, we found that both default (as proxied by Credit Rating and Outlook Index and non-default (as proxied by 3-month Fed Funds Futures determinants has significant explanatory power to sovereign bond yield spread. Extensively, we also found the significance to add volatility of 3-month Fed Funds Futures and Fed Target Rate basis and volatility of advanced stock markets as variables to stand for non-default determinants in the model. The significance of the latter model is strengthened by higher forecasting as well as indicates the significant role of US market to emerging market sovereign bond market.

Gastropod shell size and architecture influence the applicability of methods used to estimate internal volume.

Science.gov (United States)

Ragagnin, Marilia Nagata; Gorman, Daniel; McCarthy, Ian Donald; Sant'Anna, Bruno Sampaio; de Castro, Cláudio Campi; Turra, Alexander

2018-01-11

Obtaining accurate and reproducible estimates of internal shell volume is a vital requirement for studies into the ecology of a range of shell-occupying organisms, including hermit crabs. Shell internal volume is usually estimated by filling the shell cavity with water or sand, however, there has been no systematic assessment of the reliability of these methods and moreover no comparison with modern alternatives, e.g., computed tomography (CT). This study undertakes the first assessment of the measurement reproducibility of three contrasting approaches across a spectrum of shell architectures and sizes. While our results suggested a certain level of variability inherent for all methods, we conclude that a single measure using sand/water is likely to be sufficient for the majority of studies. However, care must be taken as precision may decline with increasing shell size and structural complexity. CT provided less variation between repeat measures but volume estimates were consistently lower compared to sand/water and will need methodological improvements before it can be used as an alternative. CT indicated volume may be also underestimated using sand/water due to the presence of air spaces visible in filled shells scanned by CT. Lastly, we encourage authors to clearly describe how volume estimates were obtained.

Estimating Short run and Long run Coefficients of Fundamentals Factors with Growth and Momentum Factor: Evidence from Emerging Markets

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Adnan Shoaib

2016-12-01

Full Text Available This study examines the long term relationship of risk premium and fundamental factors in emerging stock markets of China, India and Pakistan keeping in view leading contribution of Fama and French (1992 and Carhart (1997 models. Contrary to the macroeconomic multifactor models, this study incorporates firm-specific risk factors related to the market premium; size (SMB, value (HML, momentum (WML and growth (UMD as determinants of risk premium. The firm-specific growth factor is incorporated based on evidence from Ho, Strange, and Piesse (2008 by employing (UMD which is based on assets to market equity of the firm. Sample of 1198 companies from the three emerging markets for the period of 2001-2013 depicts market risk premium as the leading factor affecting risk premium in Indian and the Pakistani markets. Results reveal market momentum being high enough to overestimate coefficients in the short run. However, the relationship is stabilized and adjusted in the long run. Chinese markets, where all the risk factors seem to play their role to determine risk premium, are relatively much stable and grown-up and clearly represent maturity of the Chinese markets. Distinction between the short run and long run might be useful for the investors of the three emerging economies. According to the principle of high risk associated with high returns, small value happens to deliver higher returns with higher volatility. The growth stocks outperform value stocks in these economies.

Plot size recommendations for biomass estimation in a midwestern old-growth forest

Science.gov (United States)

Martin A. Spetich; George R Parker

1998-01-01

The authors examine the relationship between disturbance regime and plot size for woody biomass estimation in a midwestern old-growth deciduous forest from 1926 to 1992. Analysis was done on the core 19.6 ac of a 50.1 ac forest in which every tree 4 in. d.b.h. and greater has been tagged and mapped since 1926. Five windows of time are compared—1926, 1976, 1981, 1986...

A Web-based Simulator for Sample Size and Power Estimation in Animal Carcinogenicity Studies