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Sample records for general concept items

  1. A survey of anatomical items relevant to the practice of rheumatology: upper extremity, head, neck, spine, and general concepts.

    Science.gov (United States)

    Villaseñor-Ovies, Pablo; Navarro-Zarza, José Eduardo; Saavedra, Miguel Ángel; Hernández-Díaz, Cristina; Canoso, Juan J; Biundo, Joseph J; Kalish, Robert A; de Toro Santos, Francisco Javier; McGonagle, Dennis; Carette, Simon; Alvarez-Nemegyei, José

    2016-12-01

    This study aimed to identify the anatomical items of the upper extremity and spine that are potentially relevant to the practice of rheumatology. Ten rheumatologists interested in clinical anatomy who published, taught, and/or participated as active members of Clinical Anatomy Interest groups (six seniors, four juniors), participated in a one-round relevance Delphi exercise. An initial, 560-item list that included 45 (8.0 %) general concepts items; 138 (24.8 %) hand items; 100 (17.8 %) forearm and elbow items; 147 (26.2 %) shoulder items; and 130 (23.2 %) head, neck, and spine items was compiled by 5 of the participants. Each item was graded for importance with a Likert scale from 1 (not important) to 5 (very important). Thus, scores could range from 10 (1 × 10) to 50 (5 × 10). An item score of ≥40 was considered most relevant to competent practice as a rheumatologist. Mean item Likert scores ranged from 2.2 ± 0.5 to 4.6 ± 0.7. A total of 115 (20.5 %) of the 560 initial items reached relevance. Broken down by categories, this final relevant item list was composed by 7 (6.1 %) general concepts items; 32 (27.8 %) hand items; 20 (17.4 %) forearm and elbow items; 33 (28.7 %) shoulder items; and 23 (17.6 %) head, neck, and spine items. In this Delphi exercise, a group of practicing academic rheumatologists with an interest in clinical anatomy compiled a list of anatomical items that were deemed important to the practice of rheumatology. We suggest these items be considered curricular priorities when training rheumatology fellows in clinical anatomy skills and in programs of continuing rheumatology education.

  2. Item Modeling Concept Based on Multimedia Authoring

    Directory of Open Access Journals (Sweden)

    Janez Stergar

    2008-09-01

    Full Text Available In this paper a modern item design framework for computer based assessment based on Flash authoring environment will be introduced. Question design will be discussed as well as the multimedia authoring environment used for item modeling emphasized. Item type templates are a structured means of collecting and storing item information that can be used to improve the efficiency and security of the innovative item design process. Templates can modernize the item design, enhance and speed up the development process. Along with content creation, multimedia has vast potential for use in innovative testing. The introduced item design template is based on taxonomy of innovative items which have great potential for expanding the content areas and construct coverage of an assessment. The presented item design approach is based on GUI's – one for question design based on implemented item design templates and one for user interaction tracking/retrieval. The concept of user interfaces based on Flash technology will be discussed as well as implementation of the innovative approach of the item design forms with multimedia authoring. Also an innovative method for user interaction storage/retrieval based on PHP extending Flash capabilities in the proposed framework will be introduced.

  3. Item Response Theory: A Basic Concept

    Science.gov (United States)

    Mahmud, Jumailiyah

    2017-01-01

    With the development in computing technology, item response theory (IRT) develops rapidly, and has become a user friendly application in psychometrics world. Limitation in classical theory is one aspect that encourages the use of IRT. In this study, the basic concept of IRT will be discussed. In addition, it will briefly review the ability…

  4. The staging area concept for item control

    International Nuclear Information System (INIS)

    Williams, R.A.

    1984-01-01

    Accounting for special nuclear material contained in fabricated nuclear fuel rod items has been completely automated at the Westinghouse Nuclear Fuel Division facility in Columbia, South Carolina. Experience with the automated system has shown substantial difficulty in maintaining current knowledge of the precise locations of rods pulled out of the ''normal'' processing cycle. This has been resolved by creation of two tightly controlled staging areas for handling and distribution of all ''deviant'' rods by two specially trained expeditors. Thus, coupling automated data collection with centralized expert handling and distribution has created a viable system for control of large numbers of fuel rods in a major fabrication plant

  5. Analyzing force concept inventory with item response theory

    Science.gov (United States)

    Wang, Jing; Bao, Lei

    2010-10-01

    Item response theory is a popular assessment method used in education. It rests on the assumption of a probability framework that relates students' innate ability and their performance on test questions. Item response theory transforms students' raw test scores into a scaled proficiency score, which can be used to compare results obtained with different test questions. The scaled score also addresses the issues of ceiling effects and guessing, which commonly exist in quantitative assessment. We used item response theory to analyze the force concept inventory (FCI). Our results show that item response theory can be useful for analyzing physics concept surveys such as the FCI and produces results about the individual questions and student performance that are beyond the capability of classical statistics. The theory yields detailed measurement parameters regarding the difficulty, discrimination features, and probability of correct guess for each of the FCI questions.

  6. The randomly renewed general item and the randomly inspected item with exponential life distribution

    International Nuclear Information System (INIS)

    Schneeweiss, W.G.

    1979-01-01

    For a randomly renewed item the probability distributions of the time to failure and of the duration of down time and the expectations of these random variables are determined. Moreover, it is shown that the same theory applies to randomly checked items with exponential probability distribution of life such as electronic items. The case of periodic renewals is treated as an example. (orig.) [de

  7. Concept research on general passive system

    International Nuclear Information System (INIS)

    Han Xu; Yang Yanhua; Zheng Mingguang

    2009-01-01

    This paper summarized the current passive techniques used in nuclear power plants. Through classification and analysis, the functional characteristics and inherent identification of passive systems were elucidated. By improving and extending the concept of passive system, the general passive concept was proposed, and space and time relativity was discussed and assumption of general passive system were illustrated. The function of idealized general passive system is equivalent with the current passive system, but the design of idealized general passive system is more flexible. (authors)

  8. Food items and general condition of Hyperopisus bebe occidentalis ...

    African Journals Online (AJOL)

    GREG

    2017-07-20

    Jul 20, 2017 ... Key words: Food items, Hyperopisus bebe occidentalis, Warri River, condition factor. ... Sufficient food intake aids optimal growth in fish, resulting ... It covers a surface area of 255 km2 with ... examination was carried out.

  9. How Does Creating a Concept Map Affect Item-Specific Encoding?

    Science.gov (United States)

    Grimaldi, Phillip J.; Poston, Laurel; Karpicke, Jeffrey D.

    2015-01-01

    Concept mapping has become a popular learning tool. However, the processes underlying the task are poorly understood. In the present study, we examined the effect of creating a concept map on the processing of item-specific information. In 2 experiments, subjects learned categorized or ad hoc word lists by making pleasantness ratings, sorting…

  10. General Atomic's superconducting toroidal field coil concept

    International Nuclear Information System (INIS)

    Alcorn, J.; Purcell, J.

    1978-01-01

    General Atomic's concept for a superconducting toroidal field coil is presented. The concept is generic for large tokamak devices, while a specific design is indicated for a 3.8 meter (major radius) ignition/burn machine. The concept utilizes bath cooled NbTi conductor to generate a peak field of 10 tesla at 4.2 K. The design is simple and straightforward, requires a minimum of developmental effort, and draws extensively upon the perspective of past experience in the design and construction of large superconducting magnets for high energy physics. Thus, the primary emphasis is upon economy, reliability, and expeditious construction scheduling. (author)

  11. Comparing Two Types of Diagnostic Items to Evaluate Understanding of Heat and Temperature Concepts

    Science.gov (United States)

    Chu, Hye-Eun; Chandrasegaran, A. L.; Treagust, David F.

    2018-01-01

    The purpose of this research was to investigate an efficient method to assess year 8 (age 13-14) students' conceptual understanding of heat and temperature concepts. Two different types of instruments were used in this study: Type 1, consisting of multiple-choice items with open-ended justifications; and Type 2, consisting of two-tier…

  12. General mixture item response models with different item response structures: Exposition with an application to Likert scales.

    Science.gov (United States)

    Tijmstra, Jesper; Bolsinova, Maria; Jeon, Minjeong

    2018-01-10

    This article proposes a general mixture item response theory (IRT) framework that allows for classes of persons to differ with respect to the type of processes underlying the item responses. Through the use of mixture models, nonnested IRT models with different structures can be estimated for different classes, and class membership can be estimated for each person in the sample. If researchers are able to provide competing measurement models, this mixture IRT framework may help them deal with some violations of measurement invariance. To illustrate this approach, we consider a two-class mixture model, where a person's responses to Likert-scale items containing a neutral middle category are either modeled using a generalized partial credit model, or through an IRTree model. In the first model, the middle category ("neither agree nor disagree") is taken to be qualitatively similar to the other categories, and is taken to provide information about the person's endorsement. In the second model, the middle category is taken to be qualitatively different and to reflect a nonresponse choice, which is modeled using an additional latent variable that captures a person's willingness to respond. The mixture model is studied using simulation studies and is applied to an empirical example.

  13. A Generalized Logistic Regression Procedure to Detect Differential Item Functioning among Multiple Groups

    Science.gov (United States)

    Magis, David; Raiche, Gilles; Beland, Sebastien; Gerard, Paul

    2011-01-01

    We present an extension of the logistic regression procedure to identify dichotomous differential item functioning (DIF) in the presence of more than two groups of respondents. Starting from the usual framework of a single focal group, we propose a general approach to estimate the item response functions in each group and to test for the presence…

  14. Parent Ratings of ADHD Symptoms: Generalized Partial Credit Model Analysis of Differential Item Functioning across Gender

    Science.gov (United States)

    Gomez, Rapson

    2012-01-01

    Objective: Generalized partial credit model, which is based on item response theory (IRT), was used to test differential item functioning (DIF) for the "Diagnostic and Statistical Manual of Mental Disorders" (4th ed.), inattention (IA), and hyperactivity/impulsivity (HI) symptoms across boys and girls. Method: To accomplish this, parents completed…

  15. A Comparison of Item Exposure Control Procedures with the Generalized Partial Credit Model

    Science.gov (United States)

    Sanchez, Edgar Isaac

    2008-01-01

    To enhance test security of high stakes tests, it is vital to understand the way various exposure control strategies function under various IRT models. To that end the present dissertation focused on the performance of several exposure control strategies under the generalized partial credit model with an item pool of 100 and 200 items. These…

  16. Strategies for Controlling Item Exposure in Computerized Adaptive Testing with the Generalized Partial Credit Model

    Science.gov (United States)

    Davis, Laurie Laughlin

    2004-01-01

    Choosing a strategy for controlling item exposure has become an integral part of test development for computerized adaptive testing (CAT). This study investigated the performance of six procedures for controlling item exposure in a series of simulated CATs under the generalized partial credit model. In addition to a no-exposure control baseline…

  17. Modeling Answer Change Behavior: An Application of a Generalized Item Response Tree Model

    Science.gov (United States)

    Jeon, Minjeong; De Boeck, Paul; van der Linden, Wim

    2017-01-01

    We present a novel application of a generalized item response tree model to investigate test takers' answer change behavior. The model allows us to simultaneously model the observed patterns of the initial and final responses after an answer change as a function of a set of latent traits and item parameters. The proposed application is illustrated…

  18. A hierarchy of distress and invariant item ordering in the General Health Questionnaire-12.

    Science.gov (United States)

    Doyle, F; Watson, R; Morgan, K; McBride, O

    2012-06-01

    Invariant item ordering (IIO) is defined as the extent to which items have the same ordering (in terms of item difficulty/severity - i.e. demonstrating whether items are difficult [rare] or less difficult [common]) for each respondent who completes a scale. IIO is therefore crucial for establishing a scale hierarchy that is replicable across samples, but no research has demonstrated IIO in scales of psychological distress. We aimed to determine if a hierarchy of distress with IIO exists in a large general population sample who completed a scale measuring distress. Data from 4107 participants who completed the 12-item General Health Questionnaire (GHQ-12) from the Northern Ireland Health and Social Wellbeing Survey 2005-6 were analysed. Mokken scaling was used to determine the dimensionality and hierarchy of the GHQ-12, and items were investigated for IIO. All items of the GHQ-12 formed a single, strong unidimensional scale (H=0.58). IIO was found for six of the 12 items (H-trans=0.55), and these symptoms reflected the following hierarchy: anhedonia, concentration, participation, coping, decision-making and worthlessness. The cross-sectional analysis needs replication. The GHQ-12 showed a hierarchy of distress, but IIO is only demonstrated for six of the items, and the scale could therefore be shortened. Adopting brief, hierarchical scales with IIO may be beneficial in both clinical and research contexts. Copyright © 2011 Elsevier B.V. All rights reserved.

  19. The cultural fairness of the 12-item General Health Questionnaire among diverse adolescents.

    Science.gov (United States)

    Bowe, Anica

    2017-01-01

    The 12-item general health questionnaire (GHQ-12) was used in the Longitudinal Study of Young People in England (LSYPE; N = 15,770) to collect measures on adolescent mental health. Given the debate in current literature regarding the dimensionality of the GHQ-12, this study examined the cultural sensitivity of the instrument at the item level for each of the 7 major ethnic groups within the database. This study used a hybrid approach of ordinal logistic regression and item response theory (IRT) to examine the presence of differential item functioning (DIF) on the questionnaire. Results demonstrated that uniform, nonuniform, and overall DIF were present on items between White and Asian adolescents (7 items), White and Black Caribbean adolescents (1 item), and White and Black African adolescents (7 items), however all McFadden's pseudo R² effect size estimates indicated that the DIF was negligible. Overall, there were cumulative small scale level effects for the Mixed/Biracial, Asian, and Black African groups, but in each case the bias was only marginal. Findings demonstrate that the GHQ-12 can be considered culturally sensitive for adolescents from diverse ethnic groups in England, but follow-up studies are necessary. Implications for future education and health policies as well as the use of IR-based approaches for psychological instruments are discussed. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  20. Do Self Concept Tests Test Self Concept? An Evaluation of the Validity of Items on the Piers Harris and Coopersmith Measures.

    Science.gov (United States)

    Lynch, Mervin D.; Chaves, John

    Items from Peirs-Harris and Coopersmith self-concept tests were evaluated against independent measures on three self-constructs, idealized, empathic, and worth. Construct measurements were obtained with the semantic differential and D statistic. Ratings were obtained from 381 children, grades 4-6. For each test, item ratings and construct measures…

  1. CHUVARDINSKY’S ANTIGLACIAL (GENERALIZED GEOLOGICAL CONCEPTION

    Directory of Open Access Journals (Sweden)

    P. K. Skufyin

    2016-12-01

    Full Text Available Based on the analytical study of V. G. Chuvardinsky’s monographs on the revision of the generally accepted glacial theory, the authors of the review concluded that there was convincing evidence of a fault-tectonic origin of ‘ice-exaration’ relief of the Baltic Shield. Developed by Chuvardinsky, a radically new methodology of boulder prospecting of ore deposits not only refuted the old glacial theory, but also led to the discovery of copper-nickel deposits, a new apatite alkaline massif, promising manifestation of copper-nickel ore, platinum group metals, native gold, chromite and other mineral resources. A thorough drilling of ice sheets in Greenland and Antarctica for the international project determined the absence of boulder material over the entire thickness of the ice, only pulverulent and fine particles (mainly volcanic ash were found in the ice. Bottom ice layers are immobilised, their function is preservation of the geological surface. V. G. Chuvardinsky far outstripped western and Russian scientists in the field of Earth Sciences. His field studies on the Baltic Shield not only refuted the mighty glacial theory, but also created and substantiated a new geological concept instead. Professor V. Z. Negrutsa was quite right when he wrote in his review on Chuvardinsky’s work (journal Geomorfologiya, 2003, no. 1, ‘Evidence of Chuvardinsky about tectonic origin of geological and geomorphological features traditionally associated with the Quaternary glaciation is so obvious and reproducible both by field observations and by geological modeling that is presented irrefutable and undeniable in its essence’. In general, assessing the scientific significance of V. G. Chuvardinsky’s works, it can be stated that his work would have done honour to research institutes of geological and geographical orientation according to the level of study of the geological material and the value of his field studies. His books present the material for

  2. Determination of a Differential Item Functioning Procedure Using the Hierarchical Generalized Linear Model

    Directory of Open Access Journals (Sweden)

    Tülin Acar

    2012-01-01

    Full Text Available The aim of this research is to compare the result of the differential item functioning (DIF determining with hierarchical generalized linear model (HGLM technique and the results of the DIF determining with logistic regression (LR and item response theory–likelihood ratio (IRT-LR techniques on the test items. For this reason, first in this research, it is determined whether the students encounter DIF with HGLM, LR, and IRT-LR techniques according to socioeconomic status (SES, in the Turkish, Social Sciences, and Science subtest items of the Secondary School Institutions Examination. When inspecting the correlations among the techniques in terms of determining the items having DIF, it was discovered that there was significant correlation between the results of IRT-LR and LR techniques in all subtests; merely in Science subtest, the results of the correlation between HGLM and IRT-LR techniques were found significant. DIF applications can be made on test items with other DIF analysis techniques that were not taken to the scope of this research. The analysis results, which were determined by using the DIF techniques in different sample sizes, can be compared.

  3. Generalized Habituation of Concept Stimuli in Toddlers

    Science.gov (United States)

    Faulkender, Patricia J.; And Others

    1974-01-01

    An evaluation of selective generalization of habituation on the basis of meaningful categories of stimuli. Also explored are the sex differences in conceptual generalization of habituation. Subjects were 36 toddlers with a mean age of 40 months. (SDH)

  4. The KBS concepts - General outline, present study

    International Nuclear Information System (INIS)

    Pusch, R.

    1980-01-01

    The Swedish KBS 2 concept, which concerns spent, unreprocessed reactor fuel, implies the use of an 'engineered' barrier of highly compacted Na bentonite for isolating metal canisters with the wastes from the surrounding rock. The isolating power of a barrier of this kind will be so great that it will probably be suggested for other radioactive wastes as well

  5. Health state evaluation of an item: A general framework and graphical representation

    International Nuclear Information System (INIS)

    Jiang, R.; Jardine, A.K.S.

    2008-01-01

    This paper presents a general theoretical framework to evaluate the health state of an item based on condition monitoring information. The item's health state is defined in terms of its relative health level and overall health level. The former is evaluated based on the relative magnitude of the composite covariate and the latter is evaluated using a fractile life of the residual life distribution at the decision instant. In addition, a method is developed to graphically represent the degradation model, failure threshold model, and the observation history of the composite covariate. As a result, the health state of the monitored item can be intuitively presented and the evaluated result can be subsequently used in a condition-based maintenance optimization decision model, which is amenable to computer modeling. A numerical example is included to illustrate the proposed approach and its appropriateness

  6. Development and evaluation of a thermochemistry concept inventory for college-level general chemistry

    Science.gov (United States)

    Wren, David A.

    The research presented in this dissertation culminated in a 10-item Thermochemistry Concept Inventory (TCI). The development of the TCI can be divided into two main phases: qualitative studies and quantitative studies. Both phases focused on the primary stakeholders of the TCI, college-level general chemistry instructors and students. Each phase was designed to collect evidence for the validity of the interpretations and uses of TCI testing data. A central use of TCI testing data is to identify student conceptual misunderstandings, which are represented as incorrect options of multiple-choice TCI items. Therefore, quantitative and qualitative studies focused heavily on collecting evidence at the item-level, where important interpretations may be made by TCI users. Qualitative studies included student interviews (N = 28) and online expert surveys (N = 30). Think-aloud student interviews (N = 12) were used to identify conceptual misunderstandings used by students. Novice response process validity interviews (N = 16) helped provide information on how students interpreted and answered TCI items and were the basis of item revisions. Practicing general chemistry instructors (N = 18), or experts, defined boundaries of thermochemistry content included on the TCI. Once TCI items were in the later stages of development, an online version of the TCI was used in expert response process validity survey (N = 12), to provide expert feedback on item content, format and consensus of the correct answer for each item. Quantitative studies included three phases: beta testing of TCI items (N = 280), pilot testing of the a 12-item TCI (N = 485), and a large data collection using a 10-item TCI ( N = 1331). In addition to traditional classical test theory analysis, Rasch model analysis was also used for evaluation of testing data at the test and item level. The TCI was administered in both formative assessment (beta and pilot testing) and summative assessment (large data collection), with

  7. Basic general concepts in the network analysis

    Directory of Open Access Journals (Sweden)

    Boja Nicolae

    2004-01-01

    Full Text Available This survey is concerned oneself with the study of those types of material networks which can be met both in civil engineering and also in electrotechnics, in mechanics, or in hydrotechnics, and of which behavior lead to linear problems, solvable by means of Finite Element Method and adequate algorithms. Here, it is presented a unitary theory of networks met in the domains mentioned above and this one is illustrated with examples for the structural networks in civil engineering, electric circuits, and water supply networks, but also planar or spatial mechanisms can be comprised in this theory. The attention is focused to make evident the essential proper- ties and concepts in the network analysis, which differentiate the networks under force from other types of material networks. To such a network a planar, connected, and directed or undirected graph is associated, and with some vector fields on the vertex set this graph is endowed. .

  8. Predictive validity of the Work Ability Index and its individual items in the general population.

    Science.gov (United States)

    Lundin, Andreas; Leijon, Ola; Vaez, Marjan; Hallgren, Mats; Torgén, Margareta

    2017-06-01

    This study assesses the predictive ability of the full Work Ability Index (WAI) as well as its individual items in the general population. The Work, Health and Retirement Study (WHRS) is a stratified random national sample of 25-75-year-olds living in Sweden in 2000 that received a postal questionnaire ( n = 6637, response rate = 53%). Current and subsequent sickness absence was obtained from registers. The ability of the WAI to predict long-term sickness absence (LTSA; ⩾ 90 consecutive days) during a period of four years was analysed by logistic regression, from which the Area Under the Receiver Operating Characteristic curve (AUC) was computed. There were 313 incident LTSA cases among 1786 employed individuals. The full WAI had acceptable ability to predict LTSA during the 4-year follow-up (AUC = 0.79; 95% CI 0.76 to 0.82). Individual items were less stable in their predictive ability. However, three of the individual items: current work ability compared with lifetime best, estimated work impairment due to diseases, and number of diagnosed current diseases, exceeded AUC > 0.70. Excluding the WAI item on number of days on sickness absence did not result in an inferior predictive ability of the WAI. The full WAI has acceptable predictive validity, and is superior to its individual items. For public health surveys, three items may be suitable proxies of the full WAI; current work ability compared with lifetime best, estimated work impairment due to diseases, and number of current diseases diagnosed by a physician.

  9. Development of Test Items Related to Selected Concepts Within the Scheme the Particle Nature of Matter.

    Science.gov (United States)

    Doran, Rodney L.; Pella, Milton O.

    The purpose of this study was to develop tests items with a minimum reading demand for use with pupils at grade levels two through six. An item was judged to be acceptable if the item satisfied at least four of six criteria. Approximately 250 students in grades 2-6 participated in the study. Half of the students were given instruction to develop…

  10. Discrete expansions of continuum functions. General concepts

    International Nuclear Information System (INIS)

    Bang, J.; Ershov, S.N.; Gareev, F.A.; Kazacha, G.S.

    1979-01-01

    Different discrete expansions of the continuum wave functions are considered: pole expansion (according to the Mittag-Lefler theorem), Weinberg states. The general property of these groups of states is their completeness in the finite region of space. They satisfy the Schroedinger type equations and are matched with free solutions of the Schroedinger equation at the boundary. Convergence of expansions for the S matrix, the Green functions and the continuous-spectrum wave functions is studied. A new group of states possessing the best convergence is introduced

  11. TAX AUDIT AS A SEPARATE ITEM IN THE SYSTEM OF GENERAL AUDIT

    Directory of Open Access Journals (Sweden)

    Aleksey F. Akhmetshin

    2014-01-01

    Full Text Available The article describes General concepts of the audit, the purpose and the essence of the tax audit, determines the methods of calculation of the tax burden, describes the ratio of the total and tax audit. Comparative analysis with the purpose of definition of tax audit as a separate element of the system of General audit is given. Conclusion about expediency of holding events for tax audit for the purpose of reduction of tax risks of economic entities is made.

  12. Attitude Counts: Self-Concept and Success in General Chemistry

    Science.gov (United States)

    Lewis, Scott E.; Shaw, Janet L.; Heitz, Judith O.; Webster, Gail H.

    2009-06-01

    General chemistry is a required first step for students who wish to pursue a career in science or health professions. The course often has low rates of student success and as a result serves as a gateway limiting access to science fields. This study seeks to better understand factors that are related to student success in general chemistry by focusing on the affective domain, in this case students' self-concept, or self-evaluation of ability as it pertains to a specific field of study. First, a profile of students' self-concept in the general chemistry setting is created. Next, the relationship between self-concept and success in the course is investigated, including examining the role of self-concept after taking into account a cognitive measure (SAT scores). This study is unique in that evidence is found for the impact of self-concept after taking into account a cognitive measure. Finally, the effect of a semester-long, inquiry-oriented learning environment on students' self-concept is described. Suggested interventions to improve student self-concept are also discussed.

  13. Can tDCS enhance item-specific effects and generalization after linguistically motivated aphasia therapy for verbs?

    NARCIS (Netherlands)

    de Aguiar, Vania; Bastiaanse, Roelien; Capasso, Rita; Gandolfi, Marialuisa; Smania, Nicola; Rossi, Giorgio; Miceli, Gabriele

    2015-01-01

    Background: Aphasia therapy focusing on abstract properties of language promotes both item-specific effects and generalization to untreated materials. Neuromodulation with transcranial Direct Current Stimulation (tDCS) has been shown to enhance item-specific improvement, but its potential to enhance

  14. A Comparison of Item Selection Techniques and Exposure Control Mechanisms in CATs Using the Generalized Partial Credit Model.

    Science.gov (United States)

    Pastor, Dena A.; Dodd, Barbara G.; Chang, Hua-Hua

    2002-01-01

    Studied the impact of using five different exposure control algorithms in two sizes of item pool calibrated using the generalized partial credit model. Simulation results show that the a-stratified design, in comparison to a no-exposure control condition, could be used to reduce item exposure and overlap and increase pool use, while degrading…

  15. A Study of Reverse-Worded Matched Item Pairs Using the Generalized Partial Credit and Nominal Response Models

    Science.gov (United States)

    Matlock Cole, Ki Lynn; Turner, Ronna C.; Gitchel, W. Dent

    2018-01-01

    The generalized partial credit model (GPCM) is often used for polytomous data; however, the nominal response model (NRM) allows for the investigation of how adjacent categories may discriminate differently when items are positively or negatively worded. Ten items from three different self-reported scales were used (anxiety, depression, and…

  16. An inventory model for generalized weibull deteriorating items with price dependent demand and permissible delay in payments under inflation

    Directory of Open Access Journals (Sweden)

    S.P.Singh

    2015-09-01

    Full Text Available This paper derives an inventory model is developed for items that deteriorates at a generalized Weibull distributed rate when demand for the items is dependent on the selling price. Shortages are not allowed and price inflation is taken into consideration over finite planning horizon. A brief analysis of the cost involved is carried out by theoretical analysis.

  17. Reliability of the Core Items in the General Social Survey: Estimates from the Three-Wave Panels, 2006–2014

    Directory of Open Access Journals (Sweden)

    Michael Hout

    2016-11-01

    Full Text Available We used standard and multilevel models to assess the reliability of core items in the General Social Survey panel studies spanning 2006 to 2014. Most of the 293 core items scored well on the measure of reliability: 62 items (21 percent had reliability measures greater than 0.85; another 71 (24 percent had reliability measures between 0.70 and 0.85. Objective items, especially facts about demography and religion, were generally more reliable than subjective items. The economic recession of 2007–2009, the slow recovery afterward, and the election of Barack Obama in 2008 altered the social context in ways that may look like unreliability of items. For example, unemployment status, hours worked, and weeks worked have lower reliability than most work-related items, reflecting the consequences of the recession on the facts of peoples lives. Items regarding racial and gender discrimination and racial stereotypes scored as particularly unreliable, accounting for most of the 15 items with reliability coefficients less than 0.40. Our results allow scholars to more easily take measurement reliability into consideration in their own research, while also highlighting the limitations of these approaches.

  18. Concepts and recent advances in generalized information measures and statistics

    CERN Document Server

    Kowalski, Andres M

    2013-01-01

    Since the introduction of the information measure widely known as Shannon entropy, quantifiers based on information theory and concepts such as entropic forms and statistical complexities have proven to be useful in diverse scientific research fields. This book contains introductory tutorials suitable for the general reader, together with chapters dedicated to the basic concepts of the most frequently employed information measures or quantifiers and their recent applications to different areas, including physics, biology, medicine, economics, communication and social sciences. As these quantif

  19. Bayesian inference in an item response theory model with a generalized student t link function

    Science.gov (United States)

    Azevedo, Caio L. N.; Migon, Helio S.

    2012-10-01

    In this paper we introduce a new item response theory (IRT) model with a generalized Student t-link function with unknown degrees of freedom (df), named generalized t-link (GtL) IRT model. In this model we consider only the difficulty parameter in the item response function. GtL is an alternative to the two parameter logit and probit models, since the degrees of freedom (df) play a similar role to the discrimination parameter. However, the behavior of the curves of the GtL is different from those of the two parameter models and the usual Student t link, since in GtL the curve obtained from different df's can cross the probit curves in more than one latent trait level. The GtL model has similar proprieties to the generalized linear mixed models, such as the existence of sufficient statistics and easy parameter interpretation. Also, many techniques of parameter estimation, model fit assessment and residual analysis developed for that models can be used for the GtL model. We develop fully Bayesian estimation and model fit assessment tools through a Metropolis-Hastings step within Gibbs sampling algorithm. We consider a prior sensitivity choice concerning the degrees of freedom. The simulation study indicates that the algorithm recovers all parameters properly. In addition, some Bayesian model fit assessment tools are considered. Finally, a real data set is analyzed using our approach and other usual models. The results indicate that our model fits the data better than the two parameter models.

  20. Measuring social science concepts in pharmacy education research: From definition to item analysis of self-report instruments.

    Science.gov (United States)

    Cor, M Ken

    Interpreting results from quantitative research can be difficult when measures of concepts are constructed poorly, something that can limit measurement validity. Social science steps for defining concepts, guidelines for limiting construct-irrelevant variance when writing self-report questions, and techniques for conducting basic item analysis are reviewed to inform the design of instruments to measure social science concepts in pharmacy education research. Based on a review of the literature, four main recommendations emerge: These include: (1) employ a systematic process of conceptualization to derive nominal definitions; (2) write exact and detailed operational definitions for each concept, (3) when creating self-report questionnaires, write statements and select scales to avoid introducing construct-irrelevant variance (CIV); and (4) use basic item analysis results to inform instrument revision. Employing recommendations that emerge from this review will strengthen arguments to support measurement validity which in turn will support the defensibility of study finding interpretations. An example from pharmacy education research is used to contextualize the concepts introduced. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. A sharp image or a sharp knife: norms for the modality-exclusivity of 774 concept-property items.

    Science.gov (United States)

    van Dantzig, Saskia; Cowell, Rosemary A; Zeelenberg, René; Pecher, Diane

    2011-03-01

    According to recent embodied cognition theories, mental concepts are represented by modality-specific sensory-motor systems. Much of the evidence for modality-specificity in conceptual processing comes from the property-verification task. When applying this and other tasks, it is important to select items based on their modality-exclusivity. We collected modality ratings for a set of 387 properties, each of which was paired with two different concepts, yielding a total of 774 concept-property items. For each item, participants rated the degree to which the property could be experienced through five perceptual modalities (vision, audition, touch, smell, and taste). Based on these ratings, we computed a measure of modality exclusivity, the degree to which a property is perceived exclusively through one sensory modality. In this paper, we briefly sketch the theoretical background of conceptual knowledge, discuss the use of the property-verification task in cognitive research, provide our norms and statistics, and validate the norms in a memory experiment. We conclude that our norms are important for researchers studying modality-specific effects in conceptual processing.

  2. The 7-item generalized anxiety disorder scale as a tool for measuring generalized anxiety in multiple sclerosis.

    Science.gov (United States)

    Terrill, Alexandra L; Hartoonian, Narineh; Beier, Meghan; Salem, Rana; Alschuler, Kevin

    2015-01-01

    Generalized anxiety disorder (GAD) is common in multiple sclerosis (MS) but understudied. Reliable and valid measures are needed to advance clinical care and expand research in this area. The objectives of this study were to examine the psychometric properties of the 7-item Generalized Anxiety Disorder Scale (GAD-7) in individuals with MS and to analyze correlates of GAD. Participants (N = 513) completed the anxiety module of the Patient Health Questionnaire (GAD-7). To evaluate psychometric properties of the GAD-7, the sample was randomly split to conduct exploratory and confirmatory factor analyses. Based on the exploratory factor analysis, a one-factor structure was specified for the confirmatory factor analysis, which showed excellent global fit to the data (χ(2) 12 = 15.17, P = .23, comparative fit index = 0.99, root mean square error of approximation = 0.03, standardized root mean square residual = 0.03). The Cronbach alpha (0.75) indicated acceptable internal consistency for the scale. Furthermore, the GAD-7 was highly correlated with the Hospital Anxiety and Depression Scale-Anxiety (r = 0.70). Age and duration of MS were both negatively associated with GAD. Higher GAD-7 scores were observed in women and individuals with secondary progressive MS. Individuals with higher GAD-7 scores also endorsed more depressive symptoms. These findings support the reliability and internal validity of the GAD-7 for use in MS. Correlational analyses revealed important relationships with demographics, disease course, and depressive symptoms, which suggest the need for further anxiety research.

  3. Psychometric analysis of the Generalized Anxiety Disorder scale (GAD-7) in primary care using modern item response theory.

    Science.gov (United States)

    Jordan, Pascal; Shedden-Mora, Meike C; Löwe, Bernd

    2017-01-01

    The Generalized Anxiety Disorder scale (GAD-7) is one of the most frequently used diagnostic self-report scales for screening, diagnosis and severity assessment of anxiety disorder. Its psychometric properties from the view of the Item Response Theory paradigm have rarely been investigated. We aimed to close this gap by analyzing the GAD-7 within a large sample of primary care patients with respect to its psychometric properties and its implications for scoring using Item Response Theory. Robust, nonparametric statistics were used to check unidimensionality of the GAD-7. A graded response model was fitted using a Bayesian approach. The model fit was evaluated using posterior predictive p-values, item information functions were derived and optimal predictions of anxiety were calculated. The sample included N = 3404 primary care patients (60% female; mean age, 52,2; standard deviation 19.2) The analysis indicated no deviations of the GAD-7 scale from unidimensionality and a decent fit of a graded response model. The commonly suggested ultra-brief measure consisting of the first two items, the GAD-2, was supported by item information analysis. The first four items discriminated better than the last three items with respect to latent anxiety. The information provided by the first four items should be weighted more heavily. Moreover, estimates corresponding to low to moderate levels of anxiety show greater variability. The psychometric validity of the GAD-2 was supported by our analysis.

  4. Number-concept acquisition and general vocabulary development.

    Science.gov (United States)

    Negen, James; Sarnecka, Barbara W

    2012-11-01

    How is number-concept acquisition related to overall language development? Experiments 1 and 2 measured number-word knowledge and general vocabulary in a total of 59 children, ages 30-60 months. A strong correlation was found between number-word knowledge and vocabulary, independent of the child's age, contrary to previous results (D. Ansari et al., 2003). This result calls into question arguments that (a) the number-concept creation process is scaffolded mainly by visuo-spatial development and (b) that language only becomes integrated after the concepts are created (D. Ansari et al., 2003). Instead, this may suggest that having a larger nominal vocabulary helps children learn number words. Experiment 3 shows that the differences with previous results are likely due to changes in how the data were analyzed. © 2012 The Authors. Child Development © 2012 Society for Research in Child Development, Inc.

  5. [The concept of health in the General Health Law (1986)].

    Science.gov (United States)

    Peral, D

    1993-01-01

    The 1986 "Le General de Sanidad" (Sanitary General Regulations) has been studied using the method of the "Topología del Discurso" in order to elucidate what are the thoughts of the lawmakers. The law protects not only the population of catastrophes as it happened with the choleric epidemic of the XIX century, but considers a new concept a sanitary wealth should be provided to the individuals. Together with this new concept there are new ones such as equality and universalization of the sanitary assistence that would be keys of the aim of the lawmakers: to coordinate all the State resources in the reform of the spanish sanity. This includes the integration of the Universities. This can help in the understanding of the dificulties in the development and aplication of the Law present reality.

  6. Nanomedicine concepts in the general medical curriculum: initiating a discussion.

    Science.gov (United States)

    Sweeney, Aldrin E

    2015-01-01

    Various applications of nanoscale science to the field of medicine have resulted in the ongoing development of the subfield of nanomedicine. Within the past several years, there has been a concurrent proliferation of academic journals, textbooks, and other professional literature addressing fundamental basic science research and seminal clinical developments in nanomedicine. Additionally, there is now broad consensus among medical researchers and practitioners that along with personalized medicine and regenerative medicine, nanomedicine is likely to revolutionize our definitions of what constitutes human disease and its treatment. In light of these developments, incorporation of key nanomedicine concepts into the general medical curriculum ought to be considered. Here, I offer for consideration five key nanomedicine concepts, along with suggestions regarding the manner in which they might be incorporated effectively into the general medical curriculum. Related curricular issues and implications for medical education also are presented.

  7. The 12-item General Health Questionnaire (GHQ-12: translation and validation study of the Iranian version

    Directory of Open Access Journals (Sweden)

    Garmaroudi Gholamreza

    2003-11-01

    Full Text Available Abstract Background The objective of this study was to translate and to test the reliability and validity of the 12-item General Health Questionnaire (GHQ-12 in Iran. Methods Using a standard 'forward-backward' translation procedure, the English language version of the questionnaire was translated into Persian (Iranian language. Then a sample of young people aged 18 to 25 years old completed the questionnaire. In addition, a short questionnaire containing demographic questions and a single measure of global quality of life was administered. To test reliability the internal consistency was assessed by Cronbach's alpha coefficient. Validity was performed using convergent validity. Finally, the factor structure of the questionnaire was extracted by performing principal component analysis using oblique factor solution. Results In all 748 young people entered into the study. The mean age of respondents was 21.1 (SD = 2.1 years. Employing the recommended method of scoring (ranging from 0 to 12, the mean GHQ score was 3.7 (SD = 3.5. Reliability analysis showed satisfactory result (Cronbach's alpha coefficient = 0.87. Convergent validity indicated a significant negative correlation between the GHQ-12 and global quality of life scores as expected (r = -0.56, P Conclusion The study findings showed that the Iranian version of the GHQ-12 has a good structural characteristic and is a reliable and valid instrument that can be used for measuring psychological well being in Iran.

  8. Maladaptive Behaviours Associated with Generalized Anxiety Disorder: An Item Response Theory Analysis.

    Science.gov (United States)

    Mahoney, Alison E J; Hobbs, Megan J; Newby, Jill M; Williams, Alishia D; Andrews, Gavin

    2018-03-19

    Cognitive models of generalized anxiety disorder (GAD) suggest that maladaptive behaviours may contribute to the maintenance of the disorder; however, little research has concentrated on identifying and measuring these behaviours. To address this gap, the Worry Behaviors Inventory (WBI) was developed and has been evaluated within a classical test theory (CTT) approach. As CTT is limited in several important respects, this study examined the psychometric properties of the WBI using an Item Response Theory approach. A large sample of adults commencing treatment for their symptoms of GAD (n = 537) completed the WBI in addition to measures of GAD and depression symptom severity. Patients with a probable diagnosis of GAD typically engaged in four or five maladaptive behaviours most or all of the time in an attempt to prevent, control or avoid worrying about everyday concerns. The two-factor structure of the WBI was confirmed, and the WBI scales demonstrated good reliability across a broad range of the respective scales. Together with previous findings, our results suggested that hypervigilance and checking behaviours, as well as avoidance of saying or doing things that are worrisome, were the most relevant maladaptive behaviours associated with GAD, and discriminated well between adults with low, moderate and high degrees of the respective WBI scales. Our results support the importance of maladaptive behaviours to GAD and the utility of the WBI to index these behaviours. Ramifications for the classification, theoretical conceptualization and treatment of GAD are discussed.

  9. How to Reason with Economic Concepts: Cognitive Process of Japanese Undergraduate Students Solving Test Items

    Science.gov (United States)

    Asano, Tadayoshi; Yamaoka, Michio

    2015-01-01

    The authors administered a Japanese version of the Test of Understanding in College Economics, the fourth edition (TUCE-4) to assess the economic literacy of Japanese undergraduate students in 2006 and 2009. These two test results were combined to investigate students' cognitive process or reasoning with specific economic concepts and principles…

  10. Nanomedicine concepts in the general medical curriculum: initiating a discussion

    Directory of Open Access Journals (Sweden)

    Sweeney AE

    2015-12-01

    Full Text Available Aldrin E Sweeney Center for Teaching & Learning, Ross University School of Medicine, Roseau, Commonwealth of Dominica Abstract: Various applications of nanoscale science to the field of medicine have resulted in the ongoing development of the subfield of nanomedicine. Within the past several years, there has been a concurrent proliferation of academic journals, textbooks, and other professional literature addressing fundamental basic science research and seminal clinical developments in nanomedicine. Additionally, there is now broad consensus among medical researchers and practitioners that along with personalized medicine and regenerative medicine, nanomedicine is likely to revolutionize our definitions of what constitutes human disease and its treatment. In light of these developments, incorporation of key nanomedicine concepts into the general medical curriculum ought to be considered. Here, I offer for consideration five key nanomedicine concepts, along with suggestions regarding the manner in which they might be incorporated effectively into the general medical curriculum. Related curricular issues and implications for medical education also are presented. Keywords: medical education, basic science, teaching, learning, assessment, nanoscience curriculum, nanomedicine concepts

  11. Screening instruments for a population of older adults: The 10-item Kessler Psychological Distress Scale (K10) and the 7-item Generalized Anxiety Disorder Scale (GAD-7).

    Science.gov (United States)

    Vasiliadis, Helen-Maria; Chudzinski, Veronica; Gontijo-Guerra, Samantha; Préville, Michel

    2015-07-30

    Screening tools that appropriately detect older adults' mental disorders are of great public health importance. The present study aimed to establish cutoff scores for the 10-item Kessler Psychological Distress (K10) and the 7-item Generalized Anxiety Disorder (GAD-7) scales when screening for depression and anxiety. We used data from participants (n = 1811) in the Enquête sur la Santé des Aînés-Service study. Depression and anxiety were measured using DSM-V and DSM-IV criteria. Receiver operating characteristic (ROC) curve analysis provided an area under the curve (AUC) of 0.767 and 0.833 for minor and for major depression when using K10. A cutoff of 19 was found to balance sensitivity (0.794) and specificity (0.664) for minor depression, whereas a cutoff of 23 was found to balance sensitivity (0.692) and specificity (0.811) for major depression. When screening for an anxiety with GAD-7, ROC analysis yielded an AUC of 0.695; a cutoff of 5 was found to balance sensitivity (0.709) and specificity (0.568). No significant differences were found between subgroups of age and gender. Both K10 and GAD-7 were able to discriminate between cases and non-cases when screening for depression and anxiety in an older adult population of primary care service users. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  12. Volume 42, Issue5 (May 2005)Articles in the Current Issue:Developmental growth in students' concept of energy: Analysis of selected items from the TIMSS database

    Science.gov (United States)

    Liu, Xiufeng; McKeough, Anne

    2005-05-01

    The aim of this study was to develop a model of students' energy concept development. Applying Case's (1985, 1992) structural theory of cognitive development, we hypothesized that students' concept of energy undergoes a series of transitions, corresponding to systematic increases in working memory capacity. The US national sample from the Third International Mathematics and Science Study (TIMSS) database was used to test our hypothesis. Items relevant to the energy concept in the TIMSS test booklets for three populations were identified. Item difficulty from Rasch modeling was used to test the hypothesized developmental sequence, and percentage of students' correct responses was used to test the correspondence between students' age/grade level and level of the energy concepts. The analysis supported our hypothesized sequence of energy concept development and suggested mixed effects of maturation and schooling on energy concept development. Further, the results suggest that curriculum and instruction design take into consideration the developmental progression of students' concept of energy.

  13. Examining the Factor Structure and Discriminant Validity of the 12-Item General Health Questionnaire (GHQ-12) Among Spanish Postpartum Women

    Science.gov (United States)

    Aguado, Jaume; Campbell, Alistair; Ascaso, Carlos; Navarro, Purificacion; Garcia-Esteve, Lluisa; Luciano, Juan V.

    2012-01-01

    In this study, the authors tested alternative factor models of the 12-item General Health Questionnaire (GHQ-12) in a sample of Spanish postpartum women, using confirmatory factor analysis. The authors report the results of modeling three different methods for scoring the GHQ-12 using estimation methods recommended for categorical and binary data.…

  14. Hybrid-source impedance network and its generalized cascading concepts

    DEFF Research Database (Denmark)

    Li, Ding; Gao, Feng; Loh, Poh Chiang

    2009-01-01

    Hybrid-source impedance networks have attracted attention among researchers because of their flexibility in performing buck-boost energy conversion. To date, three distinct types of impedance networks can be summarized for implementing voltage-type inverters, with another three types summarized...... for current-type inverters. These impedance networks can in principle be combined into a single generic network entity, before generalized cascading concepts are proposed for connecting multiple of them together to form energy converters with a higher output voltage gain and other unique advantages...

  15. Examining item content and structure in health status and health outcomes instruments: toward the development of a grammar for better understanding of the concepts being measured.

    Science.gov (United States)

    Erickson, Pennifer; Willke, Richard J

    2013-06-01

    Health outcomes instruments assess diverse health concepts. Although item-level concepts are considered fundamental elements, the field lacks structures for evaluating and organizing them for decision making. This article proposes a grammar using item stems, response options, and recall periods to systematically identify item-level concepts. The grammar uses "core concept," "evaluative component," and "recall period" as intuitive terms for communicating with stakeholders. Better characterization of concepts is necessary for classifying instrument content and linking it to treatment benefit. Items in 2 generic and 21 disease-specific instruments were evaluated to develop and illustrate the use of the grammar. Concepts were assigned International Classification of Functioning, Disability and Health codes for exploring the value that the grammar and a classification system add to the understanding of content across instruments. The 23 instruments include many core concepts; emotional function is the only concept assessed in all instruments. Concepts in disease-specific instruments show obvious patterns; for example, arthritis instruments focus on physical function. The majority of instruments used the same response options across all items, with five-point scales being the most common. Most instruments used one recall period for all items. Shorter recall periods were used for conditions associated with "flares," such as chronic obstructive pulmonary disease and "skin disease." Every diagnosis, however, showed variation across instruments in the recall period used. This analysis indicates the proposed grammar's potential for discerning the conceptual content within and between health outcomes instruments and illustrates its value for improving communication between stakeholders and for making decisions related to treatment benefit. Copyright © 2013 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

  16. A more general model for testing measurement invariance and differential item functioning.

    Science.gov (United States)

    Bauer, Daniel J

    2017-09-01

    The evaluation of measurement invariance is an important step in establishing the validity and comparability of measurements across individuals. Most commonly, measurement invariance has been examined using 1 of 2 primary latent variable modeling approaches: the multiple groups model or the multiple-indicator multiple-cause (MIMIC) model. Both approaches offer opportunities to detect differential item functioning within multi-item scales, and thereby to test measurement invariance, but both approaches also have significant limitations. The multiple groups model allows 1 to examine the invariance of all model parameters but only across levels of a single categorical individual difference variable (e.g., ethnicity). In contrast, the MIMIC model permits both categorical and continuous individual difference variables (e.g., sex and age) but permits only a subset of the model parameters to vary as a function of these characteristics. The current article argues that moderated nonlinear factor analysis (MNLFA) constitutes an alternative, more flexible model for evaluating measurement invariance and differential item functioning. We show that the MNLFA subsumes and combines the strengths of the multiple group and MIMIC models, allowing for a full and simultaneous assessment of measurement invariance and differential item functioning across multiple categorical and/or continuous individual difference variables. The relationships between the MNLFA model and the multiple groups and MIMIC models are shown mathematically and via an empirical demonstration. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  17. Toward semantic interoperability in home health care: formally representing OASIS items for integration into a concept-oriented terminology.

    Science.gov (United States)

    Choi, Jeungok; Jenkins, Melinda L; Cimino, James J; White, Thomas M; Bakken, Suzanne

    2005-01-01

    The authors aimed to (1) formally represent OASIS-B1 concepts using the Logical Observation Identifiers, Names, and Codes (LOINC) semantic structure; (2) demonstrate integration of OASIS-B1 concepts into a concept-oriented terminology, the Medical Entities Dictionary (MED); (3) examine potential hierarchical structures within LOINC among OASIS-B1 and other nursing terms; and (4) illustrate a Web-based implementation for OASIS-B1 data entry using Dialogix, a software tool with a set of functions that supports complex data entry. Two hundred nine OASIS-B1 items were dissected into the six elements of the LOINC semantic structure and then integrated into the MED hierarchy. Each OASIS-B1 term was matched to LOINC-coded nursing terms, Home Health Care Classification, the Omaha System, and the Sign and Symptom Check-List for Persons with HIV, and the extent of the match was judged based on a scale of 0 (no match) to 4 (exact match). OASIS-B1 terms were implemented as a Web-based survey using Dialogix. Of 209 terms, 204 were successfully dissected into the elements of the LOINC semantics structure and integrated into the MED with minor revisions of MED semantics. One hundred fifty-one OASIS-B1 terms were mapped to one or more of the LOINC-coded nursing terms. The LOINC semantic structure offers a standard way to add home health care data to a comprehensive patient record to facilitate data sharing for monitoring outcomes across sites and to further terminology management, decision support, and accurate information retrieval for evidence-based practice. The cross-mapping results support the possibility of a hierarchical structure of the OASIS-B1 concepts within nursing terminologies in the LOINC database.

  18. A General Bayesian Network Approach to Analyzing Online Game Item Values and Its Influence on Consumer Satisfaction and Purchase Intention

    Science.gov (United States)

    Lee, Kun Chang; Park, Bong-Won

    Many online game users purchase game items with which to play free-to-play games. Because of a lack of research into which there is no specified framework for categorizing the values of game items, this study proposes four types of online game item values based on an analysis of literature regarding online game characteristics. It then proposes to investigate how online game users perceive satisfaction and purchase intention from the proposed four types of online game item values. Though regression analysis has been used frequently to answer this kind of research question, we propose a new approach, a General Bayesian Network (GBN), which can be performed in an understandable way without sacrificing predictive accuracy. Conventional techniques, such as regression analysis, do not provide significant explanation for this kind of problem because they are fixed to a linear structure and are limited in explaining why customers are likely to purchase game items and if they are satisfied with their purchases. In contrast, the proposed GBN provides a flexible underlying structure based on questionnaire survey data and offers robust decision support on this kind of research question by identifying its causal relationships. To illustrate the validity of GBN in solving the research question in this study, 327 valid questionnaires were analyzed using GBN with what-if and goal-seeking approaches. The experimental results were promising and meaningful in comparison with regression analysis results.

  19. An evaluation of computerized adaptive testing for general psychological distress: combining GHQ-12 and Affectometer-2 in an item bank for public mental health research.

    Science.gov (United States)

    Stochl, Jan; Böhnke, Jan R; Pickett, Kate E; Croudace, Tim J

    2016-05-20

    Recent developments in psychometric modeling and technology allow pooling well-validated items from existing instruments into larger item banks and their deployment through methods of computerized adaptive testing (CAT). Use of item response theory-based bifactor methods and integrative data analysis overcomes barriers in cross-instrument comparison. This paper presents the joint calibration of an item bank for researchers keen to investigate population variations in general psychological distress (GPD). Multidimensional item response theory was used on existing health survey data from the Scottish Health Education Population Survey (n = 766) to calibrate an item bank consisting of pooled items from the short common mental disorder screen (GHQ-12) and the Affectometer-2 (a measure of "general happiness"). Computer simulation was used to evaluate usefulness and efficacy of its adaptive administration. A bifactor model capturing variation across a continuum of population distress (while controlling for artefacts due to item wording) was supported. The numbers of items for different required reliabilities in adaptive administration demonstrated promising efficacy of the proposed item bank. Psychometric modeling of the common dimension captured by more than one instrument offers the potential of adaptive testing for GPD using individually sequenced combinations of existing survey items. The potential for linking other item sets with alternative candidate measures of positive mental health is discussed since an optimal item bank may require even more items than these.

  20. General Business Model Patterns for Local Energy Management Concepts

    Energy Technology Data Exchange (ETDEWEB)

    Facchinetti, Emanuele, E-mail: emanuele.facchinetti@hslu.ch; Sulzer, Sabine [Lucerne Competence Center for Energy Research, Lucerne University of Applied Science and Arts, Horw (Switzerland)

    2016-03-03

    The transition toward a more sustainable global energy system, significantly relying on renewable energies and decentralized energy systems, requires a deep reorganization of the energy sector. The way how energy services are generated, delivered, and traded is expected to be very different in the coming years. Business model innovation is recognized as a key driver for the successful implementation of the energy turnaround. This work contributes to this topic by introducing a heuristic methodology easing the identification of general business model patterns best suited for Local Energy Management concepts such as Energy Hubs. A conceptual framework characterizing the Local Energy Management business model solution space is developed. Three reference business model patterns providing orientation across the defined solution space are identified, analyzed, and compared. Through a market review, a number of successfully implemented innovative business models have been analyzed and allocated within the defined solution space. The outcomes of this work offer to potential stakeholders a starting point and guidelines for the business model innovation process, as well as insights for policy makers on challenges and opportunities related to Local Energy Management concepts.

  1. The Concept of General Relativity is not Related to Reality

    Science.gov (United States)

    Kotas, Ronald

    2015-04-01

    The concept of general relativity is not related to reality. It is not real or factual Science. GR cannot account for objects falling to earth or for the weight of objects sitting on the earth. The Cavendish demonstration showing the attraction between two masses at right angles to earth's gravity, is not explained by GR. No one can prove the existence of ``space fabric.'' The concept of ``space time'' effects causing gravitational attraction between masses is wrong. Conservation law of energy - momentum does not exist in GR. LIGO fails in detecting ``gravity waves'' because there is no ``space fabric'' to transmit them. The Gravity B Probe data manipulated to show some effects, is not proof of ``space fabric.'' It is Nuclear Quantum Gravitation that provides clear definitive explanation of Gravity and Gravitation. It is harmonious with Newtonian and Quantum Mechanics, and Scientific Logic. Nuclear Quantum Gravitation has 10 clear, Scientific proofs and 21 more good indications. With this theory the Physical Forces are Unified. See: OBSCURANTISM ON EINSTEIN GRAVITATION? http://www.santilli-foundation.org/inconsistencies-gravitation.php and Einstein's Theory of Relativity versus Classical Mechanics, by Paul Marmet http://www.newtonphysics.on.ca/einstein/

  2. General Business Model Patterns for Local Energy Management Concepts

    International Nuclear Information System (INIS)

    Facchinetti, Emanuele; Sulzer, Sabine

    2016-01-01

    The transition toward a more sustainable global energy system, significantly relying on renewable energies and decentralized energy systems, requires a deep reorganization of the energy sector. The way how energy services are generated, delivered, and traded is expected to be very different in the coming years. Business model innovation is recognized as a key driver for the successful implementation of the energy turnaround. This work contributes to this topic by introducing a heuristic methodology easing the identification of general business model patterns best suited for Local Energy Management concepts such as Energy Hubs. A conceptual framework characterizing the Local Energy Management business model solution space is developed. Three reference business model patterns providing orientation across the defined solution space are identified, analyzed, and compared. Through a market review, a number of successfully implemented innovative business models have been analyzed and allocated within the defined solution space. The outcomes of this work offer to potential stakeholders a starting point and guidelines for the business model innovation process, as well as insights for policy makers on challenges and opportunities related to Local Energy Management concepts.

  3. Comparative phylogeography: concepts, methods and general patterns in neotropical birds

    International Nuclear Information System (INIS)

    Arbelaez Cortes, Enrique

    2012-01-01

    Understanding the patterns and processes involved in intraspecific lineages diversification in time and space is the aim of phylogeography. The comparison of those phylogeographic patterns among co-distributed species shows insights of a community history. Here I review the concepts and methodologies of comparative phylogeography, an active research field that has heterogeneous analytical methods. In order to present a framework for phylogeography in the neotropics, I comment the general phylogeographic patterns of the birds from this region. this review is based on more than 100 studies conducted during the last 25 years and indicate that despite different co-distributed species seem to share some points in their phylogeographic pattern they have idiosyncratic aspects, indicating an unique history for each one.

  4. Yarbus's Conceptions on the General Mechanisms of Color Perception.

    Science.gov (United States)

    Nikolaev, Petr P; Rozhkova, Galina I

    2015-01-01

    In the last series of papers published during 1975 to 1980, Alfred Yarbus tried to formulate general conceptions concerning the basic principles of retinal image processing in the human visual system. The original ideas of Yarbus were based on the results of his numerous and various experiments carried out with extraordinary inventiveness and great skill. Being concentrated primarily on the problems of color vision, Alfred Yarbus dreamed of elaborating a comprehensive model that would simulate visual information processing at the monocular precognitive level in the visual system of humans with normal trichromatic color perception. In this article, the most important of Yarbus' experimental paradigms, findings, statements, and conclusions are systematized and considered in relation to the classical theories of color perception and, in particular, fundamental theses of the Nyberg school. The perceptual model developed by Alfred Yarbus remained incomplete. Nevertheless, it is already evident that some intrinsic contradictions make it inadequate in terms of comprehensive modeling. However, certain partial advantages deserve more thorough appreciation and further investigation. © The Author(s) 2015.

  5. Binomial test models and item difficulty

    NARCIS (Netherlands)

    van der Linden, Willem J.

    1979-01-01

    In choosing a binomial test model, it is important to know exactly what conditions are imposed on item difficulty. In this paper these conditions are examined for both a deterministic and a stochastic conception of item responses. It appears that they are more restrictive than is generally

  6. A Bivariate Generalized Linear Item Response Theory Modeling Framework to the Analysis of Responses and Response Times.

    Science.gov (United States)

    Molenaar, Dylan; Tuerlinckx, Francis; van der Maas, Han L J

    2015-01-01

    A generalized linear modeling framework to the analysis of responses and response times is outlined. In this framework, referred to as bivariate generalized linear item response theory (B-GLIRT), separate generalized linear measurement models are specified for the responses and the response times that are subsequently linked by cross-relations. The cross-relations can take various forms. Here, we focus on cross-relations with a linear or interaction term for ability tests, and cross-relations with a curvilinear term for personality tests. In addition, we discuss how popular existing models from the psychometric literature are special cases in the B-GLIRT framework depending on restrictions in the cross-relation. This allows us to compare existing models conceptually and empirically. We discuss various extensions of the traditional models motivated by practical problems. We also illustrate the applicability of our approach using various real data examples, including data on personality and cognitive ability.

  7. Psychometrical Assessment and Item Analysis of the General Health Questionnaire in Victims of Terrorism

    Science.gov (United States)

    Delgado-Gomez, David; Lopez-Castroman, Jorge; de Leon-Martinez, Victoria; Baca-Garcia, Enrique; Cabanas-Arrate, Maria Luisa; Sanchez-Gonzalez, Antonio; Aguado, David

    2013-01-01

    There is a need to assess the psychiatric morbidity that appears as a consequence of terrorist attacks. The General Health Questionnaire (GHQ) has been used to this end, but its psychometric properties have never been evaluated in a population affected by terrorism. A sample of 891 participants included 162 direct victims of terrorist attacks and…

  8. Student Conceptions about Energy Transformations: Progression from General Chemistry to Biochemistry

    Science.gov (United States)

    Wolfson, Adele J.; Rowland, Susan L.; Lawrie, Gwendolyn A.; Wright, Anthony H.

    2014-01-01

    Students commencing studies in biochemistry must transfer and build on concepts they learned in chemistry and biology classes. It is well established, however, that students have difficulties in transferring critical concepts from general chemistry courses; one key concept is "energy." Most previous work on students' conception of energy…

  9. U.S. Army Concept of Operations and Standard Operating Procedure for Acquisition Program Managers Using Item Unique Identification

    Science.gov (United States)

    2017-09-01

    a pop up screen will ask to file save as Figure 88. the form on my documents or desktop . Source: Department of the Army (n.d.-e...77 Open the form from desktop or mydocuments in Adobe Acrobat...policy was published as Army Directive 2016–21 in May 2016. Army items requiring serial number management will require IUID. This includes items

  10. Generalization of the Lord-Wingersky Algorithm to Computing the Distribution of Summed Test Scores Based on Real-Number Item Scores

    Science.gov (United States)

    Kim, Seonghoon

    2013-01-01

    With known item response theory (IRT) item parameters, Lord and Wingersky provided a recursive algorithm for computing the conditional frequency distribution of number-correct test scores, given proficiency. This article presents a generalized algorithm for computing the conditional distribution of summed test scores involving real-number item…

  11. A Study of General Education Astronomy Students' Understandings of Cosmology. Part III. Evaluating Four Conceptual Cosmology Surveys: An Item Response Theory Approach

    Science.gov (United States)

    Wallace, Colin S.; Prather, Edward E.; Duncan, Douglas K.

    2012-01-01

    This is the third of five papers detailing our national study of general education astronomy students' conceptual and reasoning difficulties with cosmology. In this paper, we use item response theory to analyze students' responses to three out of the four conceptual cosmology surveys we developed. The specific item response theory model we use is…

  12. Concept development of X-ray mass thickness detection for irradiated items upon electron beam irradiation processing

    Science.gov (United States)

    Qin, Huaili; Yang, Guang; Kuang, Shan; Wang, Qiang; Liu, Jingjing; Zhang, Xiaomin; Li, Cancan; Han, Zhiwei; Li, Yuanjing

    2018-02-01

    The present project will adopt the principle and technology of X-ray imaging to quickly measure the mass thickness (wherein the mass thickness of the item =density of the item × thickness of the item) of the irradiated items and thus to determine whether the packaging size and inside location of the item will meet the requirements for treating thickness upon electron beam irradiation processing. The development of algorithm of X-ray mass thickness detector as well as the prediction of dose distribution have been completed. The development of the algorithm was based on the X-ray attenuation. 4 standard modules, Al sheet, Al ladders, PMMA sheet and PMMA ladders, were selected for the algorithm development. The algorithm was optimized until the error between tested mass thickness and standard mass thickness was less than 5%. Dose distribution of all energy (1-10 MeV) for each mass thickness was obtained using Monte-carlo method and used for the analysis of dose distribution, which provides the information of whether the item will be penetrated or not, as well as the Max. dose, Min. dose and DUR of the whole item.

  13. General concept of a remote multipurpose vehicle for nuclear applications

    International Nuclear Information System (INIS)

    Devresse, M.; Costa, L.; DeBuck, F.

    1984-01-01

    A remotely operated autonomous system is presently developed for inspection and intervention inside the reactor building of nuclear power plants. The vehicle is also suitable for other nuclear and non-nuclear energy related task areas where inspection and intervention operations are taking place in hazardous environment. The goal of this remote robot is to significantly reduce personnel exposure to radiation or other risks. The system consists of five major items: an autonomous motorized carrier, two slave manipulators mounted on an interface structure, optical and environmental sensors, the digital electronic control and communication module, the man-machine interface. Main design and performance characteristics of the system are described as well as a description of the evaluation and test program

  14. The Self-Education Concept: General Notions and Structure

    Directory of Open Access Journals (Sweden)

    I. F. Medvedev

    2012-01-01

    Full Text Available The paper is devoted to the developing approach to students’ training based on the concept of self-education. The aim of the study is defined as developing the theoretical basis for self-education at Higher School. The initial research positions are derived from the methodology approach; the terminology analysis is being applied for defining the conceptual field of the research; the systematic approach gives the ground for the integral consideration of the self-education issue. The author specifies the categories and attributes of the self-education concept, its methodology basis, as well as the essence and practical conclusions, including the didactic conformities, principles and method requirements. The content of the concept in question substantiates organizational methodic arrangements of educational process including the complex of procedures for working out the normative documents, planning and organizing students’ self-educational activity, application of modern educational technologies. The re- search findings can be used by scientists, lectures, teaching staff and post-graduates in the process of implementing the innovation education technologies at Higher School. 

  15. Generalization of information-based concepts in forecast verification

    Science.gov (United States)

    Tödter, J.; Ahrens, B.

    2012-04-01

    This work deals with information-theoretical methods in probabilistic forecast verification. Recent findings concerning the Ignorance Score are shortly reviewed, then the generalization to continuous forecasts is shown. For ensemble forecasts, the presented measures can be calculated exactly. The Brier Score (BS) and its generalizations to the multi-categorical Ranked Probability Score (RPS) and to the Continuous Ranked Probability Score (CRPS) are the prominent verification measures for probabilistic forecasts. Particularly, their decompositions into measures quantifying the reliability, resolution and uncertainty of the forecasts are attractive. Information theory sets up the natural framework for forecast verification. Recently, it has been shown that the BS is a second-order approximation of the information-based Ignorance Score (IGN), which also contains easily interpretable components and can also be generalized to a ranked version (RIGN). Here, the IGN, its generalizations and decompositions are systematically discussed in analogy to the variants of the BS. Additionally, a Continuous Ranked IGN (CRIGN) is introduced in analogy to the CRPS. The applicability and usefulness of the conceptually appealing CRIGN is illustrated, together with an algorithm to evaluate its components reliability, resolution, and uncertainty for ensemble-generated forecasts. This is also directly applicable to the more traditional CRPS.

  16. Boundary curves of individual items in the distribution of total depressive symptom scores approximate an exponential pattern in a general population.

    Science.gov (United States)

    Tomitaka, Shinichiro; Kawasaki, Yohei; Ide, Kazuki; Akutagawa, Maiko; Yamada, Hiroshi; Furukawa, Toshiaki A; Ono, Yutaka

    2016-01-01

    Previously, we proposed a model for ordinal scale scoring in which individual thresholds for each item constitute a distribution by each item. This lead us to hypothesize that the boundary curves of each depressive symptom score in the distribution of total depressive symptom scores follow a common mathematical model, which is expressed as the product of the frequency of the total depressive symptom scores and the probability of the cumulative distribution function of each item threshold. To verify this hypothesis, we investigated the boundary curves of the distribution of total depressive symptom scores in a general population. Data collected from 21,040 subjects who had completed the Center for Epidemiologic Studies Depression Scale (CES-D) questionnaire as part of a national Japanese survey were analyzed. The CES-D consists of 20 items (16 negative items and four positive items). The boundary curves of adjacent item scores in the distribution of total depressive symptom scores for the 16 negative items were analyzed using log-normal scales and curve fitting. The boundary curves of adjacent item scores for a given symptom approximated a common linear pattern on a log normal scale. Curve fitting showed that an exponential fit had a markedly higher coefficient of determination than either linear or quadratic fits. With negative affect items, the gap between the total score curve and boundary curve continuously increased with increasing total depressive symptom scores on a log-normal scale, whereas the boundary curves of positive affect items, which are not considered manifest variables of the latent trait, did not exhibit such increases in this gap. The results of the present study support the hypothesis that the boundary curves of each depressive symptom score in the distribution of total depressive symptom scores commonly follow the predicted mathematical model, which was verified to approximate an exponential mathematical pattern.

  17. Boundary curves of individual items in the distribution of total depressive symptom scores approximate an exponential pattern in a general population

    Directory of Open Access Journals (Sweden)

    Shinichiro Tomitaka

    2016-10-01

    Full Text Available Background Previously, we proposed a model for ordinal scale scoring in which individual thresholds for each item constitute a distribution by each item. This lead us to hypothesize that the boundary curves of each depressive symptom score in the distribution of total depressive symptom scores follow a common mathematical model, which is expressed as the product of the frequency of the total depressive symptom scores and the probability of the cumulative distribution function of each item threshold. To verify this hypothesis, we investigated the boundary curves of the distribution of total depressive symptom scores in a general population. Methods Data collected from 21,040 subjects who had completed the Center for Epidemiologic Studies Depression Scale (CES-D questionnaire as part of a national Japanese survey were analyzed. The CES-D consists of 20 items (16 negative items and four positive items. The boundary curves of adjacent item scores in the distribution of total depressive symptom scores for the 16 negative items were analyzed using log-normal scales and curve fitting. Results The boundary curves of adjacent item scores for a given symptom approximated a common linear pattern on a log normal scale. Curve fitting showed that an exponential fit had a markedly higher coefficient of determination than either linear or quadratic fits. With negative affect items, the gap between the total score curve and boundary curve continuously increased with increasing total depressive symptom scores on a log-normal scale, whereas the boundary curves of positive affect items, which are not considered manifest variables of the latent trait, did not exhibit such increases in this gap. Discussion The results of the present study support the hypothesis that the boundary curves of each depressive symptom score in the distribution of total depressive symptom scores commonly follow the predicted mathematical model, which was verified to approximate an

  18. Bell's inequalities from the field concept in general relativity

    International Nuclear Information System (INIS)

    Sachs, M.

    1980-01-01

    A nonlinear field theory of matter, based axiomatically on general relativity, has an asymptotic, low-energy limit that predicts the outcome of experimental tests of Bell's inequalities. The inequalities should follow if spin-correlated, spin-1/2 particles, observed in coincidence, were a spacelike distance apart; they should be violated if they were separated by timelike distances. The experiment at timelike separations, for scattered protons observed in coincidence, was carried out by Lahemi-Rachti and Mittig and, thus far, agrees with this theory. Extension of the low-energy pp scattering experiment to observations at spacelike distances is suggested, with the prediction that agreement should be obtained with Bell's inequalities there. (author)

  19. Approaches to Macroevolution: 1. General Concepts and Origin of Variation.

    Science.gov (United States)

    Jablonski, David

    2017-01-01

    . The temporal and spatial patterns of the origins of evolutionary novelties are a challenge to macroevolutionary theory; individual events can be described retrospectively, but a general model relating development, genetics, and ecology is needed. An accompanying paper (Jablonski in Evol Biol 2017) reviews diversity dynamics and the sorting of variation, with some general conclusions.

  20. 100-point scale evaluating job satisfaction and the results of the 12-item General Health Questionnaire in occupational workers.

    Science.gov (United States)

    Kawada, Tomoyuki; Yamada, Natsuki

    2012-01-01

    Job satisfaction is an important factor in the occupational lives of workers. In this study, the relationship between one-dimensional scale of job satisfaction and psychological wellbeing was evaluated. A total of 1,742 workers (1,191 men and 551 women) participated. 100-point scale evaluating job satisfaction (0 [extremely dissatisfied] to 100 [extremely satisfied]) and the General Health Questionnaire, 12-item version (GHQ-12) evaluating psychological wellbeing were used. A multiple regression analysis was then used, controlling for gender and age. The change in the GHQ-12 and job satisfaction scores after a two-year interval was also evaluated. The mean age for the subjects was 42.2 years for the men and 36.2 years for the women. The GHQ-12 and job satisfaction scores were significantly correlated in each generation. The partial correlation coefficients between the changes in the two variables, controlling for age, were -0.395 for men and -0.435 for women (pjob satisfaction score was associated with the GHQ-12 results (pjob satisfaction, was significantly associated with psychological wellbeing as judged using the GHQ-12.

  1. No Retrieval-Induced Forgetting Using Item-Specific Independent Cues: Evidence against a General Inhibitory Account

    Science.gov (United States)

    Camp, Gino; Pecher, Diane; Schmidt, Henk G.

    2007-01-01

    Retrieval practice with particular items from memory can impair the recall of related items on a later memory test. This retrieval-induced forgetting effect has been ascribed to inhibitory processes (M. C. Anderson & B. A. Spellman, 1995). A critical finding that distinguishes inhibitory from interference explanations is that forgetting is found…

  2. Using the LOINC Semantic Structure to Integrate Community-based Survey Items into a Concept-based Enterprise Data Dictionary to Support Comparative Effectiveness Research.

    Science.gov (United States)

    Co, Manuel C; Boden-Albala, Bernadette; Quarles, Leigh; Wilcox, Adam; Bakken, Suzanne

    2012-01-01

    In designing informatics infrastructure to support comparative effectiveness research (CER), it is necessary to implement approaches for integrating heterogeneous data sources such as clinical data typically stored in clinical data warehouses and those that are normally stored in separate research databases. One strategy to support this integration is the use of a concept-oriented data dictionary with a set of semantic terminology models. The aim of this paper is to illustrate the use of the semantic structure of Clinical LOINC (Logical Observation Identifiers, Names, and Codes) in integrating community-based survey items into the Medical Entities Dictionary (MED) to support the integration of survey data with clinical data for CER studies.

  3. Resolution of a cosmological paradox using concepts from general relativity theory

    International Nuclear Information System (INIS)

    Silverman, A.N.

    1986-01-01

    According to the big bang theory, the universe began about 15 billion years ago and has been continually expanding ever since. If certain elementary physical concepts are naively applied to this cosmological theory, it can lead to a paradox in which distant astronomical objects seem to have lain at distances from the Earth larger than the possible size of the universe. The paradox is resolved by using concepts from general relativity theory. These concepts may appear startling to some readers

  4. Disparity between General Symptom Relief and Remission Criteria in the Positive and Negative Syndrome Scale (PANSS): A Post-treatment Bifactor Item Response Theory Model.

    Science.gov (United States)

    Anderson, Ariana E; Reise, Steven P; Marder, Stephen R; Mansolf, Maxwell; Han, Carol; Bilder, Robert M

    2017-12-01

    Objective: Total scale scores derived by summing ratings from the 30-item PANSS are commonly used in clinical trial research to measure overall symptom severity, and percentage reductions in the total scores are sometimes used to document the efficacy of treatment. Acknowledging that some patients may have substantial changes in PANSS total scores but still be sufficiently symptomatic to warrant diagnosis, ratings on a subset of 8 items, referred to here as the "Remission set," are sometimes used to determine if patients' symptoms no longer satisfy diagnostic criteria. An unanswered question remains: is the goal of treatment better conceptualized as reduction in overall symptom severity, or reduction in symptoms below the threshold for diagnosis? We evaluated the psychometric properties of PANSS total scores, to assess whether having low symptom severity post-treatment is equivalent to attaining Remission. Design: We applied a bifactor item response theory (IRT) model to post-treatment PANSS ratings of 3,647 subjects diagnosed with schizophrenia assessed at the termination of 11 clinical trials. The bifactor model specified one general dimension to reflect overall symptom severity, and five domain-specific dimensions. We assessed how PANSS item discrimination and information parameters varied across the range of overall symptom severity (θ), with a special focus on low levels of symptoms (i.e., θexpected PANSS item score of 1.83, a rating between "Absent" and "Minimal" for a PANSS symptom. Results: The application of the bifactor IRT model revealed: (1) 88% of total score variation was attributable to variation in general symptom severity, and only 8% reflected secondary domain factors. This implies that a general factor may provide a good indicator of symptom severity, and that interpretation is not overly complicated by multidimensionality; (2) Post-treatment, 534 individuals (about 15% of the whole sample) scored in the "Relief" range of general symptom

  5. The 6-Item Cognitive Impairment Test as a bedside screening for dementia in general hospital patients: results of the General Hospital Study (GHoSt).

    Science.gov (United States)

    Hessler, Johannes Baltasar; Schäufele, Martina; Hendlmeier, Ingrid; Nora Junge, Magdalena; Leonhardt, Sarah; Weber, Joshua; Bickel, Horst

    2017-07-01

    The objective of this study was to examine the psychometric quality of the 6-Item Cognitive Impairment Test (6CIT) as a bedside screening for the detection of dementia in general hospital patients. Participants (N = 1,440) were inpatients aged ≥65 of 33 randomly selected general hospitals in Southern Germany. The 6CIT was conducted at bedside, and dementia was diagnosed according to DSM-IV. Nursing staff was asked to rate the patients' cognitive status, and previous diagnoses of dementia were extracted from medical records. Completion rates and validity statistics were calculated. Two-hundred seventy patients had dementia. Cases with delirium but no dementia were excluded. Feasibility was 97.9% and 83.3% for patients without and with dementia, respectively, and decreased from moderate (93.8%) to severe dementia (53%). The area under the curve of the 6CIT was 0.98. Sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were calculated for the cutoffs 7/8 (0.96, 0.82, 0.85, 0.52, 0.99) and 10/11 (0.88, 0.95, 0.94, 0.76, 0.98). The nurse ratings and medical records information had lower validity statistics. Logistic regression analyses revealed that the 6CIT statistically significantly provided information above nurse ratings and medical records. Twenty-five and 37 additional patients were correctly classified by the 7/8 and 10/11 cutoffs, respectively. The 6CIT is a feasible and valid screening tool for the detection of dementia in older general hospital patients. The 6CIT outperformed the nurse ratings of cognitive status and dementia diagnoses from medical records, suggesting that standardized screening may have benefits with regard to case finding. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  6. A sharp image or a sharp knife: Norms for the modality-exclusivity of 774 concept-property items

    NARCIS (Netherlands)

    S. van Dantzig (Saskia); R.A. Cowell (Rosemary A.); R. Zeelenberg (René); D. Pecher (Diane)

    2011-01-01

    textabstractAccording to recent embodied cognition theories, mental concepts are represented by modality-specific sensory-motor systems. Much of the evidence for modality-specificity in conceptual processing comes from the property-verification task. When applying this and other tasks, it is

  7. The Nature of Living Systems: An Exposition of the Basic Concepts in General Systems Theory.

    Science.gov (United States)

    Miller, James G.

    General systems theory is a set of related definitions, assumptions, and propositions which deal with reality as an integrated hierarchy of organizations of matter and energy. In this paper, the author defines the concepts of space, time, matter, energy, and information in terms of their meaning in general systems theory. He defines a system as a…

  8. A possible generalization of the concept of symmetry in analytical mechanics

    International Nuclear Information System (INIS)

    Grigore, D.R.

    1987-09-01

    A theorem of Lee Hwa Chung suggests a possible generalization of the symmetry concept in classical mechanics. It is shown that the theory of Konstant-Souriau-Kirillov can be adapted to this more general case. The theory is illustrated with a number of exaples.(author)

  9. Abstract memory representations in the ventromedial prefrontal cortex and hippocampus support concept generalization.

    Science.gov (United States)

    Bowman, Caitlin R; Zeithamova, Dagmar

    2018-02-07

    Memory function involves both the ability to remember details of individual experiences and the ability to link information across events to create new knowledge. Prior research has identified the ventromedial prefrontal cortex (VMPFC) and the hippocampus as important for integrating across events in service of generalization in episodic memory. The degree to which these memory integration mechanisms contribute to other forms of generalization, such as concept learning, is unclear. The present study used a concept-learning task in humans (both sexes) coupled with model-based fMRI to test whether VMPFC and hippocampus contribute to concept generalization, and whether they do so by maintaining specific category exemplars or abstract category representations. Two formal categorization models were fit to individual subject data: a prototype model that posits abstract category representations and an exemplar model that posits category representations based on individual category members. Latent variables from each of these models were entered into neuroimaging analyses to determine whether VMPFC and the hippocampus track prototype or exemplar information during concept generalization. Behavioral model fits indicated that almost three quarters of the subjects relied on prototype information when making judgments about new category members. Paralleling prototype dominance in behavior, correlates of the prototype model were identified in VMPFC and the anterior hippocampus with no significant exemplar correlates. These results indicate that the VMPFC and portions of the hippocampus play a broad role in memory generalization and that they do so by representing abstract information integrated from multiple events. SIGNIFICANCE STATEMENT Whether people represent concepts as a set of individual category members or by deriving generalized concept representations abstracted across exemplars has been debated. In episodic memory, generalized memory representations have been shown

  10. Are reflective models appropriate for very short scales? Proofs of concept of formative models using the Ten-Item Personality Inventory.

    Science.gov (United States)

    Myszkowski, Nils; Storme, Martin; Tavani, Jean-Louis

    2018-04-27

    Because of their length and objective of broad content coverage, very short scales can show limited internal consistency and structural validity. We argue that it is because their objectives may be better aligned with formative investigations than with reflective measurement methods that capitalize on content overlap. As proofs of concept of formative investigations of short scales, we investigate the Ten Item Personality Inventory (TIPI). In Study 1, we administered the TIPI and the Big Five Inventory (BFI) to 938 adults, and fitted a formative Multiple Indicator Multiple Causes model, which consisted of the TIPI items forming 5 latent variables, which in turn predicted the 5 BFI scores. These results were replicated in Study 2, on a sample of 759 adults, with, this time, the Revised NEO Personality Inventory (NEO-PI-R) as the external criterion. The models fit the data adequately, and moderate to strong significant effects (.37<|β|<.69, all p<.001) of all 5 latent formative variables on their corresponding BFI and NEOPI-R scores were observed. This study presents a formative approach that we propose to be more consistent with the aims of scales with broad content and short length like the TIPI. This article is protected by copyright. All rights reserved. © 2018 Wiley Periodicals, Inc.

  11. The Implementation of Physics Problem Solving Strategy Combined with Concept Map in General Physics Course

    Science.gov (United States)

    Hidayati, H.; Ramli, R.

    2018-04-01

    This paper aims to provide a description of the implementation of Physic Problem Solving strategy combined with concept maps in General Physics learning at Department of Physics, Universitas Negeri Padang. Action research has been conducted in two cycles where each end of the cycle is reflected and improved for the next cycle. Implementation of Physics Problem Solving strategy combined with concept map can increase student activity in solving general physics problem with an average increase of 15% and can improve student learning outcomes from 42,7 in the cycle I become 62,7 in cycle II in general physics at the Universitas Negeri Padang. In the future, the implementation of Physic Problem Solving strategy combined with concept maps will need to be considered in Physics courses.

  12. The dynamics of generalization: From fuzzy linguistic statements to concepts and constructs

    Energy Technology Data Exchange (ETDEWEB)

    Kohout, L.J. [Florida State Univ., Tallahassee, FL (United States)

    1996-12-31

    Because of the importance of generalization, it is rather surprising that one finds less information in the literature on the nature and character of the process of generalization than one would expect. Some attention is paid to the mechanism of generalization in philosophy, artificial intelligence and cognitive science. In the AI literature, the notion of generalization appears most frequently in connection with learning. Learning through description generalization or specialization is usually performed in one of the following ways: (i) general-to-specific way (G-S), (ii) specific-to-general way (S-G). In S-G approaches the aim is to find a minimal general description that includes all the possible instances of some concept in the knowledge or data base without including any negative instances. So, the S-G approach leads to the set of concept descriptors that are more general than the input set from which it is derived. Problem that any universal generalization must face is the problem of exceptions. In logic, one way of handling exceptions is non-monotonic reasoning. Another example of an AI device that can generalize is a Neural Network (NN) used for classification of patterns. Advantages and disadvantages of this approach will be discussed.

  13. Investigating domain-general short-term memory for order versus specific item memory in developmental dyslexia

    OpenAIRE

    Hachmann, Wibke Maria

    2012-01-01

    Recent findings suggest that people with dyslexia experience difficulties with the learning of serial order information during the transition from short- to long-term memory. At the same time, models of short-term memory increasingly incorporate a distinction of order and item processing. This work aims to investigate whether serial order processing deficiencies in dyslexia can be traced back to a selective impairment of short-term memory for serial order, and whether this impairment also aff...

  14. Self-esteem, general and sexual self-concepts in blind people.

    Science.gov (United States)

    Salehi, Mehrdad; Azarbayejani, Abas; Shafiei, Katayoun; Ziaei, Tayebe; Shayegh, Bahar

    2015-10-01

    People with visual disability have lower self-esteem and social skills than sighted people. This study was designed to describe self-esteem and general and sexual self-concepts in blind people. This was a cross-sectional study, conducted in the Isfahan University of Medical Sciences in 2013-2014. In this study, 138 visually impaired people participated from Isfahan Province Welfare Organization and were interviewed for measuring of self-esteem and self-concept using Eysenck self-esteem and Rogers' self-concept questionnaires. The correlation between above two variables was measured using Statistical Package for the Social Sciences (SPSS) software by Pearson correlation test. Mean [± standard deviation (SD)] age of patients was 30.9 ± 8 years. The mean (±SD) of general self-concept score was 11 ± 5.83. The mean (±SD) of self-esteem score was 16.62 ± 2.85. Pearson correlation results showed a significant positive correlation between self-esteem and general self-concept (r = 0.19, P = 0.025). The mean of sexual self-concept scores in five subscales (sexual anxiety, sexual self-efficacy, sexual self-esteem, sexual fear, and sexual depression) were correspondingly 11 ± 4.41, 19.53 ± 4.53, 12.96 ± 4.19, 13.48 ± 1.76, and 5.38 ± 2.36. Self-esteem and self-concept had significant positive correlation with sexual anxiety (r = 0.49; P Self-esteem and self-concept had significant correlation with sexual anxiety and sexual fear; and negative correlation with sexual self-efficacy and sexual-esteem.

  15. What We Don't Test: What an Analysis of Unreleased ACS Exam Items Reveals about Content Coverage in General Chemistry Assessments

    Science.gov (United States)

    Reed, Jessica J.; Villafan~e, Sachel M.; Raker, Jeffrey R.; Holme, Thomas A.; Murphy, Kristen L.

    2017-01-01

    General chemistry courses are often the foundation for the study of other science disciplines and upper-level chemistry concepts. Students who take introductory chemistry courses are more often from health and science-related fields than chemistry. As such, the content taught and assessed in general chemistry courses is envisioned as building…

  16. Basic concepts in the management of heart failure in general clinical ...

    African Journals Online (AJOL)

    Basic concepts in the management of heart failure in general clinical practice. KO Ogunyankin. Abstract. No Abstract. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT · AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors ...

  17. Conceptions of the Nature of Science--Are They General or Context Specific?

    Science.gov (United States)

    Urhahne, Detlef; Kremer, Kerstin; Mayer, Juergen

    2011-01-01

    The study investigates the relationship between general and context-specific conceptions of the nature of science (NOS). The categorization scheme by Osborne et al. (J Res Sci Teach 40:692-720, "2003") served as the theoretical framework of the study. In the category "nature of scientific knowledge", the certainty, development, simplicity,…

  18. Longitudinal Factor Structure of General Self-Concept and Locus of Control among High School Students

    Science.gov (United States)

    Wang, Ze; Su, Ihui

    2013-01-01

    This study examined the longitudinal factor structure of general self-concept and locus of control among high school students over a 4-year period, with data from the National Educational Longitudinal Study of 1988. Measurement invariance was tested over time and across gender and ethnic groups; second-order piecewise latent growth models were…

  19. First-Year Cadets' Conceptions of General Education Writing at a Senior Military College

    Science.gov (United States)

    Rifenburg, J. Michael; Forester, Brian

    2018-01-01

    This study investigates conceptions first-year cadets at a US senior military college bring to general education writing courses, often termed first-year composition (FYC). Using a mixed methods research design, we received survey responses from 122 cadets and conducted semi-structured in-person interviews with four first-year cadets. Our data…

  20. Evidence of the Generalization and Construct Representation Inferences for the "GRE"® Revised General Test Sentence Equivalence Item Type. ETS GRE® Board Research Report. ETS GRE®-17-02. ETS Research Report. RR-17-05

    Science.gov (United States)

    Bejar, Isaac I.; Deane, Paul D.; Flor, Michael; Chen, Jing

    2017-01-01

    The report is the first systematic evaluation of the sentence equivalence item type introduced by the "GRE"® revised General Test. We adopt a validity framework to guide our investigation based on Kane's approach to validation whereby a hierarchy of inferences that should be documented to support score meaning and interpretation is…

  1. On-Demand Testing and Maintaining Standards for General Qualifications in the UK Using Item Response Theory: Possibilities and Challenges

    Science.gov (United States)

    He, Qingping

    2012-01-01

    Background: Although on-demand testing is being increasingly used in many areas of assessment, it has not been adopted in high stakes examinations like the General Certificate of Secondary Education (GCSE) and General Certificate of Education Advanced level (GCE A level) offered by awarding organisations (AOs) in the UK. One of the major issues…

  2. Multidimensional Generalized Functions in Aeroacoustics and Fluid Mechanics. Part 1; Basic Concepts and Operations

    Science.gov (United States)

    Farassat, Fereidoun; Myers, Michael K.

    2011-01-01

    This paper is the first part of a three part tutorial on multidimensional generalized functions (GFs) and their applications in aeroacoustics and fluid mechanics. The subject is highly fascinating and essential in many areas of science and, in particular, wave propagation problems. In this tutorial, we strive to present rigorously and clearly the basic concepts and the tools that are needed to use GFs in applications effectively and with ease. We give many examples to help the readers in understanding the mathematical ideas presented here. The first part of the tutorial is on the basic concepts of GFs. Here we define GFs, their properties and some common operations on them. We define the important concept of generalized differentiation and then give some interesting elementary and advanced examples on Green's functions and wave propagation problems. Here, the analytic power of GFs in applications is demonstrated with ease and elegance. Part 2 of this tutorial is on the diverse applications of generalized derivatives (GDs). Part 3 is on generalized Fourier transformations and some more advanced topics. One goal of writing this tutorial is to convince readers that, because of their powerful operational properties, GFs are absolutely essential and useful in engineering and physics, particularly in aeroacoustics and fluid mechanics.

  3. General concept of a gas engine for a hybrid vehicle, operating on methanol dissociation products

    International Nuclear Information System (INIS)

    Tartakovsky, L.; Aleinikov, Y.; Fainberg, V.; Garbar, A.; Gutman, M.; Hetsroni, G.; Schindler, Y.; Zvirin, Y.

    1998-01-01

    The paper presents a general concept of a hybrid propulsion system, based on an SI internal combustion engine fueled by methanol dissociation products (MDP). The proposed hybrid propulsion scheme is a series hybrid, which allows the engine to be operated in an on-off mode at constant optimal regime. The engine is fed by gaseous products of methanol dissociation (mainly hydrogen and carbon monoxide) emerging from an on-board catalytic reformer. The general scheme and base operation features of the propulsion system are described. The benefits that may be achieved by combining the well-known idea of on-board methanol dissociation with the hybrid vehicle concept are discussed. The proposed scheme is compared with those of systems operating on gasoline, liquid methanol, hydrogen and also with the multi-regime (not hybrid) engine fed by MDP

  4. Distributing learning over time: the spacing effect in children's acquisition and generalization of science concepts.

    Science.gov (United States)

    Vlach, Haley A; Sandhofer, Catherine M

    2012-01-01

    The spacing effect describes the robust finding that long-term learning is promoted when learning events are spaced out in time rather than presented in immediate succession. Studies of the spacing effect have focused on memory processes rather than for other types of learning, such as the acquisition and generalization of new concepts. In this study, early elementary school children (5- to 7-year-olds; N = 36) were presented with science lessons on 1 of 3 schedules: massed, clumped, and spaced. The results revealed that spacing lessons out in time resulted in higher generalization performance for both simple and complex concepts. Spaced learning schedules promote several types of learning, strengthening the implications of the spacing effect for educational practices and curriculum. © 2012 The Authors. Child Development © 2012 Society for Research in Child Development, Inc.

  5. Estimated general population control limits for unitary agents in drinking water, milk, soil, and unprocessed food items

    Energy Technology Data Exchange (ETDEWEB)

    Watson, A.P.; Adams, J.D.; Cerar, R.J.; Hess, T.L.; Kistner, S.L.; Leffingwell, S.S.; MacIntosh, R.G.; Ward, J.R.

    1992-01-01

    In the event of an unplanned release of chemical agent during any stage of the Chemical Stockpile Disposal Program (CSDP), the potential exists for contamination of drinking water, forage crops, grains, garden produce, and livestock. Persistent agents such as VX or sulfur mustard pose the greatest human health concern for reentry. This White Paper has been prepared to provide technical bases for these decisions by developing working estimates of agent control limits in selected environmental media considered principal sources of potential human exposure. To date, control limits for public exposure to unitary agents have been established for atmospheric concentrations only. The current analysis builds on previous work to calculate working estimates of control limits for ingestion and dermal exposure to potentially contaminated drinking water, milk, soil, and unprocessed food items such as garden produce. Information characterizing agent desorption from, and detection on or in, contaminated porous media are presently too developed to permit reasonable estimation of dermal exposure from this source. Thus, dermal contact with potentially contaminated porous surfaces is not considered in this document.

  6. Generalization of risk concept in case risk components depend on time

    International Nuclear Information System (INIS)

    Volkov, Yu.V.

    2006-01-01

    Ratios of risk assessments vs. nuclear technologies objects have been obtained for cases when that kind of risk components as accident probability and the consequent damage depend on time. Such generalization of risk concept ensures new possibilities for performing the probabilistic safety analysis which have been demonstrated with simple models in the present paper. As an example safety of radioactive storage with one-component activity has been analyzed with a very simple model [ru

  7. A Rejoinder to Mackintosh and some Remarks on the Concept of General Intelligence

    OpenAIRE

    Heene, Moritz

    2008-01-01

    In 2000 Nicholas J. Mackintosh (2000) published an article in "Nature" referring to the concept of general intelligence ("g") claiming that there is clear empirical evidence for the existence of the g factor and psychologists are "united in their support of g". Surprisingly, his view remained yet unchallenged although this issue is by no means as clear-cut as Mackintosh argues. Let us therefore attempt to clarify some common but unfortunately major misconceptions about g, which Mackintosh, fo...

  8. A Rejoinder to Mackintosh and some Remarks on the Concept of General Intelligence

    OpenAIRE

    Heene, Moritz

    2017-01-01

    In 2000 Nicholas J. Mackintosh (2000) published an article in Nature referring to the concept of general intelligence (“g”) claiming that there is clear empirical evidence for the existence of the g factor and psychologists are “...united in their support of g”. Surprisingly, his view remained yet unchallenged although this issue is by no means as clear-cut as Mackintosh argues. Let us therefore attempt to clarify some common but unfortunately major misconceptions about g, which Mackintosh, f...

  9. General formulation of standard model the standard model is in need of new concepts

    International Nuclear Information System (INIS)

    Khodjaev, L.Sh.

    2001-01-01

    The phenomenological basis for formulation of the Standard Model has been reviewed. The Standard Model based on the fundamental postulates has been formulated. The concept of the fundamental symmetries has been introduced: To look for not fundamental particles but fundamental symmetries. By searching of more general theory it is natural to search first of all global symmetries and than to learn consequence connected with the localisation of this global symmetries like wise of the standard Model

  10. Self-esteem, general and sexual self-concepts in blind people

    OpenAIRE

    Salehi, Mehrdad; Azarbayejani, Abas; Shafiei, Katayoun; Ziaei, Tayebe; Shayegh, Bahar

    2015-01-01

    Background: People with visual disability have lower self-esteem and social skills than sighted people. This study was designed to describe self-esteem and general and sexual self-concepts in blind people. Materials and Methods: This was a cross-sectional study, conducted in the Isfahan University of Medical Sciences in 2013-2014. In this study, 138 visually impaired people participated from Isfahan Province Welfare Organization and were interviewed for measuring of self-esteem and self-conce...

  11. Sustainable refurbishment of exterior walls and building facades. Final report, Part B - General refurbishment concepts

    Energy Technology Data Exchange (ETDEWEB)

    Vares, S.; Pulakka, S.; Toratti, T. [and others

    2012-11-01

    This report is the second part of the final report of Sustainable refurbishment of building facades and exterior walls (SUSREF). SUSREF project was a collaborative (small/medium size) research project within the 7th Framework Programme of the Commission and it was financed under the theme Environment (including climate change) (Grant agreement no. 226858). The project started in October 1st 2009 and ended in April 30th 2012. The project included 11 partners from five countries. SUSREF developed sustainable concepts and technologies for the refurbishment of building facades and external walls. This report together with SUSREF Final report Part B and SUSREF Final Report Part C introduce the main results of the project. Part A focuses on methodological issues. The descriptions of the concepts and the assessment results of the developed concepts are presented in SUSREF Final report part B (generic concepts) and SUSREF Final report Part C (SME concepts). The following list shows the sustainability assessment criteria defined by the SUSREF project. These are Durability; Impact on energy demand for heating; Impact on energy demand for cooling; Impact on renewable energy use potential; Impact on daylight; Environmental impact of manufacture and maintenance; Indoor air quality and acoustics; Structural stability; Fire safety; Aesthetic quality; Effect on cultural heritage; Life cycle costs; Need for care and maintenance; Disturbance to the tenants and to the site; Buildability. This report presents sustainability assessment results of general refurbishment concepts and gives recommendations on the basis of the results. The report covers the following refurbishment cases - External insulation - Internal insulation - Cavity wall insulation - Replacement Insulation during renovation.

  12. ABOUT THE GENERAL CONCEPT OF THE UNIVERSAL STORAGE SYSTEM AND PRACTICE-ORIENTED DATA PROCESSING

    Directory of Open Access Journals (Sweden)

    L. V. Rudikova

    2017-01-01

    Full Text Available Approaches evolution and concept of data accumulation in warehouse and subsequent Data Mining use is perspective due to the fact that, Belarusian segment of the same IT-developments is organizing. The article describes the general concept for creation a system of storage and practice-oriented data analysis, based on the data warehousing technology. The main aspect in universal system design on storage layer and working with data is approach uses extended data warehouse, based on universal platform of stored data, which grants access to storage and subsequent data analysis different structure and subject domains have compound’s points (nodes and extended functional with data structure choice option for data storage and subsequent intrasystem integration. Describe the universal system general architecture of storage and analysis practice-oriented data, structural elements. Main components of universal system for storage and processing practice-oriented data are: online data sources, ETL-process, data warehouse, subsystem of analysis, users. An important place in the system is analytical processing of data, information search, document’s storage and providing a software interface for accessing the functionality of the system from the outside. An universal system based on describing concept will allow collection information of different subject domains, get analytical summaries, do data processing and apply appropriate Data Mining methods and algorithms.

  13. Artificial General Intelligence: Concept, State of the Art, and Future Prospects

    Science.gov (United States)

    Goertzel, Ben

    2014-12-01

    In recent years broad community of researchers has emerged, focusing on the original ambitious goals of the AI field - the creation and study of software or hardware systems with general intelligence comparable to, and ultimately perhaps greater than, that of human beings. This paper surveys this diverse community and its progress. Approaches to defining the concept of Artificial General Intelligence (AGI) are reviewed including mathematical formalisms, engineering, and biology inspired perspectives. The spectrum of designs for AGI systems includes systems with symbolic, emergentist, hybrid and universalist characteristics. Metrics for general intelligence are evaluated, with a conclusion that, although metrics for assessing the achievement of human-level AGI may be relatively straightforward (e.g. the Turing Test, or a robot that can graduate from elementary school or university), metrics for assessing partial progress remain more controversial and problematic.

  14. Lessons learned from Fukushima Daiichi nuclear power plant accident: efficient education items of radiation safety for general public.

    Science.gov (United States)

    Ohno, K; Endo, K

    2015-07-01

    The Fukushima Daiichi nuclear power plant (FNP-1) accident, while as tragic as the tsunami, was a man-made disaster created by the ignorance of the effects of radiation and radioactive materials. Therefore, it is important that all specialists in radiation protection in medicine sympathize with the anxiety of the general public regarding the harmful effects of radiation and advise people accordingly. All questions and answers were collected related to inquiries from the general public that were posted to reliable websites, including those of the government and radiation-related organizations, from March 2011 to November 2012. The questions were summarized and classified by similarity of content. (1) The total number of questions is 372. The content was broadly classified into three categories: inquiries for radiation-related knowledge and about health effects and foods. The questions asked to obtain radiation-related knowledge were the most common, accounting for 38 %. Thirty-six percentage of the questions were related to health effects, and 26 % involved foods, whereas 18 % of the questions were related to children and pregnancy. (2) The change over time was investigated in 290 questions for which the time of inquiry was known. Directly after the earthquake, the questions were primarily from people seeking radiation-related knowledge. Later, questions related to health effects increased. The anxiety experienced by residents following the nuclear accident was caused primarily by insufficient knowledge related to radiation, concerns about health effects and uncertainties about food and water safety. The development of educational materials focusing on such content will be important for risk communication with the general public in countries with nuclear power plants. Physicians and medical physicist should possess the ability to respond to questions such as these and should continue with medical examinations and treatments in a safe and appropriate manner. © The

  15. Lessons learned from Fukushima Daiichi nuclear power plant accident: efficient education items of radiation safety for general public

    International Nuclear Information System (INIS)

    Ohno, K.; Endo, K.

    2015-01-01

    The Fukushima Daiichi nuclear power plant (FNP-1) accident, while as tragic as the tsunami, was a man-made disaster created by the ignorance of the effects of radiation and radioactive materials. Therefore, it is important that all specialists in radiation protection in medicine sympathize with the anxiety of the general public regarding the harmful effects of radiation and advise people accordingly. All questions and answers were collected related to inquiries from the general public that were posted to reliable web sites, including those of the government and radiation-related organizations, from March 2011 to November 2012. The questions were summarized and classified by similarity of content. (1) The total number of questions is 372. The content was broadly classified into three categories: inquiries for radiation-related knowledge and about health effects and foods. The questions asked to obtain radiation-related knowledge were the most common, accounting for 38 %. Thirty-six percentage of the questions were related to health effects, and 26 % involved foods, whereas 18 % of the questions were related to children and pregnancy. (2) The change over time was investigated in 290 questions for which the time of inquiry was known. Directly after the earthquake, the questions were primarily from people seeking radiation-related knowledge. Later, questions related to health effects increased. The anxiety experienced by residents following the nuclear accident was caused primarily by insufficient knowledge related to radiation, concerns about health effects and uncertainties about food and water safety. The development of educational materials focusing on such content will be important for risk communication with the general public in countries with nuclear power plants. Physicians and medical physicist should possess the ability to respond to questions such as these and should continue with medical examinations and treatments in a safe and appropriate manner

  16. Quality of life in the Danish general population--normative data and validity of WHOQOL-BREF using Rasch and item response theory models

    DEFF Research Database (Denmark)

    Noerholm, V; Groenvold, M; Watt, T

    2004-01-01

    BACKGROUND: The main objective of this study was to investigate the construct validity of the WHOQOL-BREF by use of Rasch and Item Response Theory models and to examine the stability of the model across high/low scoring individuals, gender, education, and depressive illness. Furthermore......, the objective of the study was to estimate the reference data for the quality of life questionnaire WHOQOL-BREF in the general Danish population and in subgroups defined by age, gender, and education. METHODS: Mail-out-mail-back questionnaires were sent to a randomly selected sample of the Danish general...... population. The response rate was 68.5%, and the sample reported here contained 1101 respondents: 578 women and 519 men (four respondents did not indicate their genders). RESULTS: Each of the four domains of the WHOQOL-BREF scale fitted a two-parameter IRT model, but did not fit the Rasch model. Due...

  17. Microbial contaminants isolated from items and work surfaces in the post- operative ward at Kawolo general hospital, Uganda.

    Science.gov (United States)

    Sserwadda, Ivan; Lukenge, Mathew; Mwambi, Bashir; Mboowa, Gerald; Walusimbi, Apollo; Segujja, Farouk

    2018-02-06

    Nosocomial infections are a major setback in the healthcare delivery system especially in developing countries due to the limited resources. The roles played by medical care equipment and work surfaces in the transmission of such organisms have inevitably contributed to the elevated mortality, morbidity and antibiotic resistances. A total 138 samples were collected during the study from Kawolo general hospital. Swab samples were collected from various work surfaces and fomites which consisted of; beds, sink taps, infusion stands, switches, work tables and scissors. Cultures were done and the susceptibility patterns of the isolates were determined using Kirby Bauer disc diffusion method. Data was analyzed using Stata 13 and Microsoft Excel 2013 packages. A total of 44.2% (61/138) of the collected swab specimens represented the overall bacterial contamination of the sampled articles. Staphylococcus aureus and Klebsiella pneumoniae accounted for the highest bacterial contaminants constituting of 75.4% (46/61) and 11.5% (7/61) respectively. Infusion stands and patient beds were found to have the highest bacterial contamination levels both constituting 19.67% (12/61). The highest degree of transmission of organisms to patients was found to be statistically significant for patient beds with OR: 20.1 and P-value 8X10 - 4 . Vancomycin, ceftriaxone and ciprofloxacin were the most effective antibiotics with 100%, 80% and 80% sensitivity patterns among the isolates respectively. Multi-drug resistant (MDR) Staphylococcus aureus accounted for 52% (24/46) with 4% (1/24) classified as a possible extensively drug resistant (XDR) whereas Gram negative isolates had 27% (4/15) MDR strains out of which 50%(2/4) were classified as possible pan-drug resistant (PDR). The high prevalence of bacterial contaminants in the hospital work environment is an indicator of poor or ineffective decontamination. The study findings reiterate the necessity to formulate drug usage policies and re

  18. Generalizing ecological site concepts of the Colorado Plateau for landscape-level applications

    Science.gov (United States)

    Duniway, Michael C.; Nauman, Travis; Johanson, Jamin K.; Green, Shane; Miller, Mark E.; Bestelmeyer, Brandon T.

    2016-01-01

    Numerous ecological site descriptions in the southern Utah portion of the Colorado Plateau can be difficult to navigate, so we held a workshop aimed at adding value and functionality to the current ecological site system.We created new groups of ecological sites and drafted state-and-transition models for these new groups.We were able to distill the current large number of ecological sites in the study area (ca. 150) into eight ecological site groups that capture important variability in ecosystem dynamics.Several inventory and monitoring programs and landscape scale planning actions will likely benefit from more generalized ecological site group concepts.

  19. Why do participants initiate free recall of short lists of words with the first list item? Toward a general episodic memory explanation.

    Science.gov (United States)

    Spurgeon, Jessica; Ward, Geoff; Matthews, William J

    2014-11-01

    Participants who are presented with a short list of words for immediate free recall (IFR) show a strong tendency to initiate their recall with the 1st list item and then proceed in forward serial order. We report 2 experiments that examined whether this tendency was underpinned by a short-term memory store, of the type that is argued by some to underpin recency effects in IFR. In Experiment 1, we presented 3 groups of participants with lists of between 2 and 12 words for IFR, delayed free recall, and continuous-distractor free recall. The to-be-remembered words were simultaneously spoken and presented visually, and the distractor task involved silently solving a series of self-paced, visually presented mathematical equations (e.g., 3 + 2 + 4 = ?). The tendency to initiate recall at the start of short lists was greatest in IFR but was also present in the 2 other recall conditions. This finding was replicated in Experiment 2, where the to-be-remembered items were presented visually in silence and the participants spoke aloud their answers to computer-paced mathematical equations. Our results necessitate that a short-term buffer cannot be fully responsible for the tendency to initiate recall from the beginning of a short list; rather, they suggest that the tendency represents a general property of episodic memory that occurs across a range of time scales. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  20. ALERT. Adverse late effects of cancer treatment. Vol. 1. General concepts and specific precepts

    Energy Technology Data Exchange (ETDEWEB)

    Rubin, Philip; Constine, Louis S. [Univ. Rochester Medical Center, NY (United States). Dept. of Radiation Oncology; Marks, Lawrence B. (ed.) [Univ. North Carolina and Lineberger, Comprehensive Cancer Center, Chapel Hill, NC (United States). Dept. of Radiation Oncology

    2014-09-01

    Considers in detail the general concepts and principles relevant to the adverse late effects of cancer treatment. Explains the molecular, cytologic and histopathologic events that lead to altered physiologic and metabolic functions and their clinical manifestations. Includes chapters on legal issues, economic aspects, nursing, psychological issues and quality of life. The literature on the late effects of cancer treatment is widely scattered in different journals since all major organ systems are affected and management is based on a variety of medical and surgical treatments. The aim of ALERT - Adverse Late Effects of Cancer Treatment is to offer a coherent multidisciplinary approach to the care of cancer survivors. The central paradigm is that cytotoxic multimodal therapy results in a perpetual cascade of events that affects each major organ system differently and is expressed continually over time. Essentially, radiation and chemotherapy are intense biologic modifiers that allow for cancer cure and cancer survivorship but accelerate senescence of normal tissues and increase the incidence of age-related diseases and second malignant tumors. Volume 1 of this two-volume work focuses on the general concepts and principles relevant to late effects and on the dynamic interplay of molecular, cytologic and histopathologic events that lead to altered physiologic and metabolic functions and their clinical manifestations. Chapters are also included on legal issues, economic aspects, nursing, psychological issues and quality of life.

  1. ALERT. Adverse late effects of cancer treatment. Vol. 1. General concepts and specific precepts

    International Nuclear Information System (INIS)

    Rubin, Philip; Constine, Louis S.; Marks, Lawrence B.

    2014-01-01

    Considers in detail the general concepts and principles relevant to the adverse late effects of cancer treatment. Explains the molecular, cytologic and histopathologic events that lead to altered physiologic and metabolic functions and their clinical manifestations. Includes chapters on legal issues, economic aspects, nursing, psychological issues and quality of life. The literature on the late effects of cancer treatment is widely scattered in different journals since all major organ systems are affected and management is based on a variety of medical and surgical treatments. The aim of ALERT - Adverse Late Effects of Cancer Treatment is to offer a coherent multidisciplinary approach to the care of cancer survivors. The central paradigm is that cytotoxic multimodal therapy results in a perpetual cascade of events that affects each major organ system differently and is expressed continually over time. Essentially, radiation and chemotherapy are intense biologic modifiers that allow for cancer cure and cancer survivorship but accelerate senescence of normal tissues and increase the incidence of age-related diseases and second malignant tumors. Volume 1 of this two-volume work focuses on the general concepts and principles relevant to late effects and on the dynamic interplay of molecular, cytologic and histopathologic events that lead to altered physiologic and metabolic functions and their clinical manifestations. Chapters are also included on legal issues, economic aspects, nursing, psychological issues and quality of life.

  2. Item validity vs. item discrimination index: a redundancy?

    Science.gov (United States)

    Panjaitan, R. L.; Irawati, R.; Sujana, A.; Hanifah, N.; Djuanda, D.

    2018-03-01

    In several literatures about evaluation and test analysis, it is common to find that there are calculations of item validity as well as item discrimination index (D) with different formula for each. Meanwhile, other resources said that item discrimination index could be obtained by calculating the correlation between the testee’s score in a particular item and the testee’s score on the overall test, which is actually the same concept as item validity. Some research reports, especially undergraduate theses tend to include both item validity and item discrimination index in the instrument analysis. It seems that these concepts might overlap for both reflect the test quality on measuring the examinees’ ability. In this paper, examples of some results of data processing on item validity and item discrimination index were compared. It would be discussed whether item validity and item discrimination index can be represented by one of them only or it should be better to present both calculations for simple test analysis, especially in undergraduate theses where test analyses were included.

  3. General practitioners' and district nurses' conceptions of the encounter with obese patients in primary health care

    Directory of Open Access Journals (Sweden)

    Rasmussen Finn

    2011-02-01

    Full Text Available Abstract Background Primary health care specialists have a key role in the management of obesity. Through understanding how they conceive the encounter with patients with obesity, treatment may be improved. The aim of this study was thus to explore general practitioners' and district nurses' conceptions of encountering patients with obesity in primary health care. Method Data were collected through semi-structured interviews, and analysed using a phenomenographic approach. The participants were 10 general practitioners (6 women, 4 men and 10 district nurses (7 women, 3 men from 19 primary health care centres within a well-defined area of Sweden. Results Five descriptive categories were identified: Adequate primary health care, Promoting lifestyle change, Need for competency, Adherence to new habits and Understanding patient attitudes. All participants, independent of gender and profession, were represented in the descriptive categories. Some profession and gender differences were, however, found in the underlying conceptions. The general staff view was that obesity had to be prioritised. However, there was also the contradictory view that obesity is not a disease and therefore not the responsibility of primary health care. Despite this, staff conceived it as important that patients were met with respect and that individual solutions were provided which could be adhered to step-by-step by the patient. Patient attitudes, such as motivation to change, evasive behaviour, too much trust in care and lack of self-confidence, were, however, conceived as major barriers to a fruitful encounter. Conclusions Findings from this study indicate that there is a need for development and organisation of weight management in primary health care. Raising awareness of staff's negative views of patient attitudes is important since it is likely that it affects the patient-staff relationship and staff's treatment efforts. More research is also needed on gender and

  4. Parallel Evolution in Science: The Historical Roots and Central Concepts of General Systems Theory; and "General Systems Theory,""Modern Organizational Theory," and Organizational Communication.

    Science.gov (United States)

    Lederman, Linda Costigan; Rogers, Don

    The two papers in this document focus on general systems theory. In her paper, Linda Lederman discusses the emergence and evolution of general systems theory, defines its central concepts, and draws some conclusions regarding the nature of the theory and its value as an epistemology. Don Rogers, in his paper, relates some of the important features…

  5. Boundary curves of individual items in the distribution of total depressive symptom scores approximate an exponential pattern in a general population

    OpenAIRE

    Tomitaka, Shinichiro; Kawasaki, Yohei; Ide, Kazuki; Akutagawa, Maiko; Yamada, Hiroshi; Furukawa, Toshiaki A.; Ono, Yutaka

    2016-01-01

    [Background]Previously, we proposed a model for ordinal scale scoring in which individual thresholds for each item constitute a distribution by each item. This lead us to hypothesize that the boundary curves of each depressive symptom score in the distribution of total depressive symptom scores follow a common mathematical model, which is expressed as the product of the frequency of the total depressive symptom scores and the probability of the cumulative distribution function of each item th...

  6. Relationship of sexual assault with self-concept and general health in victims referred to forensic Center in Ahvaz city.

    Science.gov (United States)

    Alboebadi, F; Afshari, P; Jamshidi, F; Poor, Rm; Cheraghi, M

    We aimed to study the relationship of sexual assault with self-concept and the general health of the victims referred to forensics in Ahvaz city (Iran). It was a cross-sectional descriptive and analytical study that was designed by two groups as case and control which has done on 128 subjects. Sixty-four rape victims who were referred to the forensic center, considered as case group and in control group, 64 people who were being referred to health clinics in Ahvaz city. The data were collected through Rogers's standard self-concept and general health questionnaires. Questionnaires were filled in self-completion way. Data had entered and analyzed by using SPSS software (version 22). A level of significance was less than 0.05. The average score of self-concept in the case group was 14.97 ±4.78 and in control group was 6.08 ±2.9. Average score of general health of the case and control groups, respectively, were 51.09 ±18.07 and 16.92 ±12.79. A significant statistical difference between the average score of self-concept, social functioning, physical and general health components in the groups was observed. More negative self-concept and vulnerable general health was observed in the rape victims group than in the control group. Providing counseling and health services and family and social support of these victims can be effective in their general health promotion.

  7. A Framework for Seismic Design of Items in Safety-Critical Facilities for Implementing a Risk-Informed Defense-in-Depth-Based Concept

    Directory of Open Access Journals (Sweden)

    Tatsuya Itoi

    2017-05-01

    Full Text Available Recently, especially after the 2011 off the Pacific coast of Tohoku earthquake and the Fukushima Daiichi nuclear power plant accident, the need for treating residual risks and cliff-edge effects in safety-critical facilities has been widely recognized as an extremely important issue. In this article, the sophistication of seismic designs in safety-critical facilities is discussed from the viewpoint of mitigating the consequences of accidents, such as the avoidance of cliff-edge effects. For this purpose, the implementation of a risk-informed defense-in-depth-based framework is proposed in this study. A basic framework that utilizes diversity in the dynamic characteristics of items and also provides additional seismic margin to items important for safety when needed is proposed to prevent common cause failure and to avoid cliff-edge effects as far as practicable. The proposed method is demonstrated to be effective using an example calculation.

  8. Glucose intolerance and General Health Questionnaire 12-item version scores of male two-shift workers stratified by precariousness of work.

    Science.gov (United States)

    Kawada, Tomoyuki

    2016-01-01

    This study examined the relationship between precariousness of work, glucose intolerance and psychological wellbeing for male workers, stratified by age. I recruited 2542 manufacturing two-shift workers, aged from 35 to 54 years. Glucose intolerance was defined as fasting plasma glucose of ≥100mg/dL or current medication of diabetes mellitus. The rating scale of General Health Questionnaire 12-item version (GHQ-12) was used for evaluating psychological well-being. There was a significant increase in the prevalence of glucose intolerance by aging in permanent workers. In addition, the prevalence of glucose intolerance except 30s and the prevalence of positive GHQ-12 scores except 50s of permanent workers were both significantly higher than that of temporary workers in each age class. Temporary workers in this study sign contracts for 3 years, and heather worker's effect, compared with permanent workers, would be reflected in this study. Copyright © 2015 Diabetes India. Published by Elsevier Ltd. All rights reserved.

  9. Letter dated 18 October 1999 from the Permanent Representative of China to the United Nations addressed to the Secretary-General. Uphold the ABM Treaty, push forward nuclear disarmament process and promote international peace and security. General Assembly. 54. session. First Committee. Agenda item 76. General and complete disarmament

    International Nuclear Information System (INIS)

    1999-01-01

    The document reproduces the text of the letter dated 18 October 1999 sent to the Secretary-General by the Permanent Representative of China to the United Nations in connection with the agenda item 76 (General and complete disarmament) of the 54th session of the General Assembly, First Committee. The letter expresses the position of the Chinese delegation concerning the proposed amendment of the Anti-Ballistic Missile Treaty (ABM Treaty)

  10. A clinical trial design using the concept of proportional time using the generalized gamma ratio distribution.

    Science.gov (United States)

    Phadnis, Milind A; Wetmore, James B; Mayo, Matthew S

    2017-11-20

    Traditional methods of sample size and power calculations in clinical trials with a time-to-event end point are based on the logrank test (and its variations), Cox proportional hazards (PH) assumption, or comparison of means of 2 exponential distributions. Of these, sample size calculation based on PH assumption is likely the most common and allows adjusting for the effect of one or more covariates. However, when designing a trial, there are situations when the assumption of PH may not be appropriate. Additionally, when it is known that there is a rapid decline in the survival curve for a control group, such as from previously conducted observational studies, a design based on the PH assumption may confer only a minor statistical improvement for the treatment group that is neither clinically nor practically meaningful. For such scenarios, a clinical trial design that focuses on improvement in patient longevity is proposed, based on the concept of proportional time using the generalized gamma ratio distribution. Simulations are conducted to evaluate the performance of the proportional time method and to identify the situations in which such a design will be beneficial as compared to the standard design using a PH assumption, piecewise exponential hazards assumption, and specific cases of a cure rate model. A practical example in which hemorrhagic stroke patients are randomized to 1 of 2 arms in a putative clinical trial demonstrates the usefulness of this approach by drastically reducing the number of patients needed for study enrollment. Copyright © 2017 John Wiley & Sons, Ltd.

  11. [ISO 15189 accreditation in clinical microbiology laboratory: general concepts and the status in our laboratory].

    Science.gov (United States)

    Akyar, Işin

    2009-10-01

    One important trend in the laboratory profession and quality management is the global convergence of laboratory operations. The goal of an accredited medical laboratory is to continue "offering useful laboratory service for diagnosis and treatment of the patients and also aid to the health of the nation". An accredited clinical laboratory is managed by a quality control system, it is competent technically and the laboratory service meets the needs of all its patients and physicians by taking the responsibility of all the medical tests and therapies. For this purpose, ISO 15189 international standard has been prepared by 2003. ISO 15189 standard is originated from the arrangement of ISO 17025 and ISO 9001:2000 standards. Many countries such as England, Germany, France, Canada and Australia have preferred ISO 15189 as their own laboratory accreditation programme, meeting all the requirements of their medical laboratories. The accreditation performance of a clinical microbiology laboratory is mainly based on five essential points; preanalytical, analytical, postanalytical, quality control programmes (internal, external, interlaboratory) and audits (internal, external). In this review article, general concepts on ISO 15189 accreditation standards for the clinical microbiology laboratories have been summarized and the status of a private laboratory (Acibadem LabMed, Istanbul) in Turkey has been discussed.

  12. The General Adaptation Syndrome: A Foundation for the Concept of Periodization.

    Science.gov (United States)

    Cunanan, Aaron J; DeWeese, Brad H; Wagle, John P; Carroll, Kevin M; Sausaman, Robert; Hornsby, W Guy; Haff, G Gregory; Triplett, N Travis; Pierce, Kyle C; Stone, Michael H

    2018-04-01

    Recent reviews have attempted to refute the efficacy of applying Selye's general adaptation syndrome (GAS) as a conceptual framework for the training process. Furthermore, the criticisms involved are regularly used as the basis for arguments against the periodization of training. However, these perspectives fail to consider the entirety of Selye's work, the evolution of his model, and the broad applications he proposed. While it is reasonable to critically evaluate any paradigm, critics of the GAS have yet to dismantle the link between stress and adaptation. Disturbance to the state of an organism is the driving force for biological adaptation, which is the central thesis of the GAS model and the primary basis for its application to the athlete's training process. Despite its imprecisions, the GAS has proven to be an instructive framework for understanding the mechanistic process of providing a training stimulus to induce specific adaptations that result in functional enhancements. Pioneers of modern periodization have used the GAS as a framework for the management of stress and fatigue to direct adaptation during sports training. Updates to the periodization concept have retained its founding constructs while explicitly calling for scientifically based, evidence-driven practice suited to the individual. Thus, the purpose of this review is to provide greater clarity on how the GAS serves as an appropriate mechanistic model to conceptualize the periodization of training.

  13. Generalized concepts for measures in case of nuclear and radiological emergencies; Generalisierte Konzepte fuer Massnahmen bei nuklearen und radiologischen Notfaellen

    Energy Technology Data Exchange (ETDEWEB)

    Sogalla, Martin; Buettner, Uwe; Schnadt, Horst

    2015-05-15

    In the frame of the project 3610S60014 GRS has developed a generalized concept of measures for an improved availability of support and information systems for emergency purposes and the planning of press and public relations that shall be applicable for the complete spectrum of nuclear end radiological emergencies. The concept allows the derivation of criteria and clear procedures for the situation evaluation and decision making. The project is aimed to integrate all available measure concepts from external emergency preparedness, prevention of ABD hazards and specific nuclear emergency plans.

  14. Determination Motive through the Prism of the General Concept of the Motives of Human Behaviour

    Science.gov (United States)

    Veresha, Roman V.

    2016-01-01

    This research studies the problems of defining the concept of motive of crime in terms of the psychological concept of motives of human behavior. The purpose of this research is to define the motive of crime (which is yet undefined in spite of the longstanding existence of criminology) and to improve existing scientific theories regarding the…

  15. Effects of Students' Pre- and Post-Laboratory Concept Maps on Students' Attitudes toward Chemistry Laboratory in University General Chemistry

    Science.gov (United States)

    Kilic, Ziya; Kaya, Osman Nafiz; Dogan, Alev

    2004-01-01

    The purpose of this study was to investigate the effects of scientific discussions based on student-constructed pre- and post-laboratory concept maps on students' attitudes toward chemistry laboratory in the university general chemistry. As part of instruction, during the first four laboratory sessions, students were taught how to construct and…

  16. General concepts of ventricular function, Myocardial perfusion, and exercise physiology relevant to nuclear cardiology

    International Nuclear Information System (INIS)

    Kronenberg, M.W.; Becker, L.C.

    1988-01-01

    Knowledge of ventricular mechanics, the physiology of the coronary circulation, and exercise physiology is necessary for the accurate interpretation of radionuclide ventriculographic and myocardial perfusion images. This chapter outlines these important basic concepts as applied to the whole heart

  17. Why Do Participants Initiate Free Recall of Short Lists of Words with the First List Item? Toward a General Episodic Memory Explanation

    Science.gov (United States)

    Spurgeon, Jessica; Ward, Geoff; Matthews, William J.

    2014-01-01

    Participants who are presented with a short list of words for immediate free recall (IFR) show a strong tendency to initiate their recall with the 1st list item and then proceed in forward serial order. We report 2 experiments that examined whether this tendency was underpinned by a short-term memory store, of the type that is argued by some to…

  18. A Comparison of Item Selection Procedures Using Different Ability Estimation Methods in Computerized Adaptive Testing Based on the Generalized Partial Credit Model

    Science.gov (United States)

    Ho, Tsung-Han

    2010-01-01

    Computerized adaptive testing (CAT) provides a highly efficient alternative to the paper-and-pencil test. By selecting items that match examinees' ability levels, CAT not only can shorten test length and administration time but it can also increase measurement precision and reduce measurement error. In CAT, maximum information (MI) is the most…

  19. Biomass energy projects in Central and Eastern Europe. General information, favorable concepts and financing possibilities

    International Nuclear Information System (INIS)

    Ellenbroek, R.; Ballard-Tremeer, G.; Koeks, R.; Venendaal, R.

    2000-08-01

    The purpose of this guide is to provide information on the possibilities to invest and carry out biomass energy projects in Central and Eastern Europe. In the first part of the guide background information is given on countries in Central and Eastern Europe, focusing on bio-energy. A few cases are presented to illustrate different biomass energy concepts. Based on economic calculations an indication is given of the feasibility of those concepts. Also the most relevant sources of information are listed. In the second part an overview is given of Dutch, European and international financial tools that can be used in biomass energy projects in Central and Eastern Europe

  20. Smallest detectable change and test-retest reliability of a self-reported outcome measure: Results of the Center for Epidemiologic Studies Depression Scale, General Self-Efficacy Scale, and 12-item General Health Questionnaire.

    Science.gov (United States)

    Ohno, Shotaro; Takahashi, Kana; Inoue, Aimi; Takada, Koki; Ishihara, Yoshiaki; Tanigawa, Masaru; Hirao, Kazuki

    2017-12-01

    This study aims to examine the smallest detectable change (SDC) and test-retest reliability of the Center for Epidemiologic Studies Depression Scale (CES-D), General Self-Efficacy Scale (GSES), and 12-item General Health Questionnaire (GHQ-12). We tested 154 young adults at baseline and 2 weeks later. We calculated the intra-class correlation coefficients (ICCs) for test-retest reliability with a two-way random effects model for agreement. We then calculated the standard error of measurement (SEM) for agreement using the ICC formula. The SEM for agreement was used to calculate SDC values at the individual level (SDC ind ) and group level (SDC group ). The study participants included 137 young adults. The ICCs for all self-reported outcome measurement scales exceeded 0.70. The SEM of CES-D was 3.64, leading to an SDC ind of 10.10 points and SDC group of 0.86 points. The SEM of GSES was 1.56, leading to an SDC ind of 4.33 points and SDC group of 0.37 points. The SEM of GHQ-12 with bimodal scoring was 1.47, leading to an SDC ind of 4.06 points and SDC group of 0.35 points. The SEM of GHQ-12 with Likert scoring was 2.44, leading to an SDC ind of 6.76 points and SDC group of 0.58 points. To confirm that the change was not a result of measurement error, a score of self-reported outcome measurement scales would need to change by an amount greater than these SDC values. This has important implications for clinicians and epidemiologists when assessing outcomes. © 2017 John Wiley & Sons, Ltd.

  1. Buyer social responsibility: a general concept and its implications for marketing management

    NARCIS (Netherlands)

    Ingenbleek, P.T.M.; Meulenberg, M.T.G.; Trijp, van J.C.M.

    2015-01-01

    The inclusion of sustainability concerns in consumer decision-making poses new challenges to marketing. The existing literature contains a variety of concepts and definitions that pertain to social issues in consumption but lacks an overarching conceptualisation of buyer social responsibility (BSR)

  2. Using automatic item generation to create multiple-choice test items.

    Science.gov (United States)

    Gierl, Mark J; Lai, Hollis; Turner, Simon R

    2012-08-01

    Many tests of medical knowledge, from the undergraduate level to the level of certification and licensure, contain multiple-choice items. Although these are efficient in measuring examinees' knowledge and skills across diverse content areas, multiple-choice items are time-consuming and expensive to create. Changes in student assessment brought about by new forms of computer-based testing have created the demand for large numbers of multiple-choice items. Our current approaches to item development cannot meet this demand. We present a methodology for developing multiple-choice items based on automatic item generation (AIG) concepts and procedures. We describe a three-stage approach to AIG and we illustrate this approach by generating multiple-choice items for a medical licensure test in the content area of surgery. To generate multiple-choice items, our method requires a three-stage process. Firstly, a cognitive model is created by content specialists. Secondly, item models are developed using the content from the cognitive model. Thirdly, items are generated from the item models using computer software. Using this methodology, we generated 1248 multiple-choice items from one item model. Automatic item generation is a process that involves using models to generate items using computer technology. With our method, content specialists identify and structure the content for the test items, and computer technology systematically combines the content to generate new test items. By combining these outcomes, items can be generated automatically. © Blackwell Publishing Ltd 2012.

  3. The general concept for a spallation neutron source in the Federal Republic of Germany

    International Nuclear Information System (INIS)

    Bauer, G.S.

    1982-01-01

    In a collaborative effort between the two German nuclear research centres at Karlsruhe and at Juelich, a reference concept for a spallation neutron source has been studied which would be suitable to satisfy the medium term needs in neutrons for fundamental research and to serve a large number of other scientific disciplines as well. The reference facility, consisting of a high power proton linac for 5 mA time average current of 1.1 GeV protons and a rotating lead target with hybrid H 2 O-D 2 O moderators can deliver a thermal neutron flux equivalent to 7 x 10 14 cm -2 s -1 at the beam tube noses. Pulsed operation of the accelerator results in an intensity modulation of this flux at a repitition rate of 100 Hz with a peak flux of 1.3 x 10 16 cm -2 s -1 and a pulse width of 510 μs. Further possible improvements were considered, consisting in the use of uranium as target material and in the addition of a proton pulse compressor to increase the neutron peak flux especially in the epithermal energy range and to provide a time structure suitable for neutrino and muon research. To realize this concept in a fashion compatible with existing constraints while still serving a maximum number of users at the earliest possible date, a staged concept is being considered by KFA Juelich. (orig.) [de

  4. Generalized correlation integral vectors: A distance concept for chaotic dynamical systems

    Energy Technology Data Exchange (ETDEWEB)

    Haario, Heikki, E-mail: heikki.haario@lut.fi [School of Engineering Science, Lappeenranta University of Technology, Lappeenranta (Finland); Kalachev, Leonid, E-mail: KalachevL@mso.umt.edu [Department of Mathematical Sciences, University of Montana, Missoula, Montana 59812-0864 (United States); Hakkarainen, Janne [Earth Observation Unit, Finnish Meteorological Institute, Helsinki (Finland)

    2015-06-15

    Several concepts of fractal dimension have been developed to characterise properties of attractors of chaotic dynamical systems. Numerical approximations of them must be calculated by finite samples of simulated trajectories. In principle, the quantities should not depend on the choice of the trajectory, as long as it provides properly distributed samples of the underlying attractor. In practice, however, the trajectories are sensitive with respect to varying initial values, small changes of the model parameters, to the choice of a solver, numeric tolerances, etc. The purpose of this paper is to present a statistically sound approach to quantify this variability. We modify the concept of correlation integral to produce a vector that summarises the variability at all selected scales. The distribution of this stochastic vector can be estimated, and it provides a statistical distance concept between trajectories. Here, we demonstrate the use of the distance for the purpose of estimating model parameters of a chaotic dynamic model. The methodology is illustrated using computational examples for the Lorenz 63 and Lorenz 95 systems, together with a framework for Markov chain Monte Carlo sampling to produce posterior distributions of model parameters.

  5. Using Differential Item Functioning Procedures to Explore Sources of Item Difficulty and Group Performance Characteristics.

    Science.gov (United States)

    Scheuneman, Janice Dowd; Gerritz, Kalle

    1990-01-01

    Differential item functioning (DIF) methodology for revealing sources of item difficulty and performance characteristics of different groups was explored. A total of 150 Scholastic Aptitude Test items and 132 Graduate Record Examination general test items were analyzed. DIF was evaluated for males and females and Blacks and Whites. (SLD)

  6. Comparative efficacy of the generalized anxiety disorder 7-item scale and the Edinburgh Postnatal Depression Scale as screening tools for generalized anxiety disorder in pregnancy and the postpartum period.

    Science.gov (United States)

    Simpson, William; Glazer, Melanie; Michalski, Natalie; Steiner, Meir; Frey, Benicio N

    2014-08-01

    About 24.1% of pregnant women suffer from at least 1 anxiety disorder, 8.5% of whom suffer specifically from generalized anxiety disorder (GAD). GAD is often associated with major depressive disorder (MDD). During the perinatal period, the presence of physical and somatic symptoms often makes differentiation between depression and anxiety more challenging. To date, no screening tools have been developed to detect GAD in the perinatal population. We investigated the psychometric properties of the GAD 7-item Scale (GAD-7) as a screening tool for GAD in pregnant and postpartum women. Two hundred and forty perinatal women (n = 155 pregnant and n = 85 postpartum) referred for psychiatric consultation were enrolled. On the day of initial assessment, all women completed the GAD-7 and the Edinburgh Postnatal Depression Scale (EPDS). Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition-based diagnoses were made by experienced psychiatrists. Scores from the GAD-7 and EPDS were compared with the clinical diagnoses to evaluate the psychometric properties of the GAD-7 and EPDS when used as a screening tool for GAD. The GAD-7 yielded a sensitivity of 61.3% and specificity of 72.7% at an optimal cut-off score of 13. Compared with the EPDS and the EPDS-3A subscale, the GAD-7 displayed greater accuracy and specificity over a greater range of cut-off scores and more accurately identified GAD in patients with comorbid MDD. Our findings suggest that the GAD-7 represents a clinically useful scale for the detection of GAD in perinatal women.

  7. The principle of general covariance and the principle of equivalence: two distinct concepts

    International Nuclear Information System (INIS)

    Fagundes, H.V.

    It is shown how to construct a theory with general covariance but without the equivalence principle. Such a theory is in disagreement with experiment, but it serves to illustrate the independence of the former principle from the latter one [pt

  8. The generalized Balescu-Lenard collision operator: A unifying concept for tokamak transport

    International Nuclear Information System (INIS)

    Mynick, H.E.

    1987-08-01

    The generalization of the Balescu-Lenard collision operator to its fully electromagnetic counterpart in Kaufman's action-angle formalism is derived and its properties investigated. The general form may be specialized to any particular geometry where the unperturbed particle motion is integrable, and thus includes cylindrical plasmas, inhomogeneous slabs with nonuniform magnetic fields, tokamaks, and the particularly simple geometry of the standard operator as special cases. The general form points to the commonality between axisymmetric, turbulent, and ripple transport, and implies properties (e.g., intrinsic ambipolarity) which should be shared by them, under appropriate conditions. Along with a turbulent ''anomalous diffusion coefficient'' calculated for tokamaks in previous work, an ''anomalous pinch'' term of closely related structure and scaling is also implied by the generalized operator. 20 refs

  9. Acoustic and vibration monitoring systems and its place in the general conception of NPP diagnostics

    International Nuclear Information System (INIS)

    Dmitriev, V.; Kudryavtsev, B.; Morozov, S.; Finkel, B.

    1993-01-01

    Concept of diagnostics as a matter is an identification of defects and malfunctions in operating equipment by analyzing some data containing the information about these defects or malfunctions, but received without their direct observation. The direct observation of some parameters may be impossible in principle (for example, coolant saturation temperature), or because of inaccessibility for its measuring (for example, temperature of fuel elements), or because of the absence of a suitable sensor at a proper place. And, on the contrary, in some cases there is too much information for its simple interpretation. This report describes various monitoring systems of reactor components.Application is made to a pwr type reactor

  10. The concept of "psychosomatic" in general practice. Reflections on body language and a tentative model for understanding.

    Science.gov (United States)

    Mattsson, Bengt; Mattsson, Monica

    2002-09-01

    In medicine, the concept "psychosomatic" indicates both dualism and polarisation. "Could it mean something psychic or is it something somatic?" This artificial dichotomy and body/mind split is not as apparent in general practice as it is in other medical disciplines. In general practice, the prerequisites for a division are overlooked. Following the work of Piaget, the article outlines manifestations of a body/mind unity as exposed in the language. Words and expressions describing the way we move, stand and walk therefore indicate our attitude and state of mind. Our body language conveys a message. The importance of breathing and its relation to our emotions is highlighted. The function of breathing is said to represent a bridge between the conscious and the unconscious--breathing can be controlled by our will, but generally we breathe reflexively. Restricted breathing is not just a mechanical process; it is shown that there is a connection between breathing and our emotions. Finally, a model of the "human organism" is presented linking four concepts, "human activity", "organ functions", "physical body" and "neurophysiological functions". Activities within the different systems are linked and relate to each other. The model supports the necessity to overcome the body/mind split, which is one of the obstacles to the fulfillment of good quality general practice.

  11. General definition of the concept of "sport" as one of the basic constructs of the general theory of physical culture and sports theory

    Directory of Open Access Journals (Sweden)

    Vasil Sutula

    2018-02-01

    Full Text Available Purpose: to reveal modern ideas about the essence of the concept of "sport" and determine its role in the development of the general theory of physical culture and sports theory. Material & Methods: analysis of specialized literature, which highlights various aspects of the development of the field of people's activities related to the use of physical exercises. Results: in today's society there is an objective sphere of human activity related to the use of physical exercises, for which the name in domestic and foreign scientific and social practice is most often used the term "physical culture". Conclusion: the constitutive conditions of the process of developing a general theory of physical culture are singled out, it is shown that sport, as a special socio-cultural phenomenon, is a historically conditioned activity of people associated with the use of physical exercises, aimed at preparing and participating in competitions, as well as individual and socially significant results of such activity.

  12. Representing general theoretical concepts in structural equation models: The role of composite variables

    Science.gov (United States)

    Grace, J.B.; Bollen, K.A.

    2008-01-01

    Structural equation modeling (SEM) holds the promise of providing natural scientists the capacity to evaluate complex multivariate hypotheses about ecological systems. Building on its predecessors, path analysis and factor analysis, SEM allows for the incorporation of both observed and unobserved (latent) variables into theoretically-based probabilistic models. In this paper we discuss the interface between theory and data in SEM and the use of an additional variable type, the composite. In simple terms, composite variables specify the influences of collections of other variables and can be helpful in modeling heterogeneous concepts of the sort commonly of interest to ecologists. While long recognized as a potentially important element of SEM, composite variables have received very limited use, in part because of a lack of theoretical consideration, but also because of difficulties that arise in parameter estimation when using conventional solution procedures. In this paper we present a framework for discussing composites and demonstrate how the use of partially-reduced-form models can help to overcome some of the parameter estimation and evaluation problems associated with models containing composites. Diagnostic procedures for evaluating the most appropriate and effective use of composites are illustrated with an example from the ecological literature. It is argued that an ability to incorporate composite variables into structural equation models may be particularly valuable in the study of natural systems, where concepts are frequently multifaceted and the influence of suites of variables are often of interest. ?? Springer Science+Business Media, LLC 2007.

  13. General practice, primary care, and health service psychology: concepts, competencies, and the Combined-Integrated model.

    Science.gov (United States)

    Schulte, Timothy J; Isley, Elayne; Link, Nancy; Shealy, Craig N; Winfrey, LaPearl Logan

    2004-10-01

    The profession of psychology is being impacted profoundly by broader changes within the national system of health care, as mental and behavioral health services are being recognized as essential components of a comprehensive, preventive, and cost-efficient primary care system. To fully define and embrace this role, the discipline of professional psychology must develop a shared disciplinary identity of health service psychology and a generalized competency-based model for doctoral education and training. This very framework has been adopted by Combined-Integrated (C-I) doctoral programs in professional psychology, which train across the practice areas (clinical, counseling, and school psychology) to provide a general and integrative foundation for their students. Because C-I programs produce general practitioners who are competent to function within a variety of health service settings, this innovative training approach has great potential to educate and train psychologists for a changing health care marketplace. Copyright 2004 Wiley Periodicals, Inc.

  14. NICOLAS MALEBRANCHE: FROM THE THEORY OF “GENERAL WILL” TO THE CONCEPT OF “INCLINATION”

    Directory of Open Access Journals (Sweden)

    CRISTIAN MOISUC

    2014-11-01

    Full Text Available The period between 1670 and 1740 is considered a time of “crisis of Christian rationalism” (A. McKenna or a time of “skepticism” (V.Cousin, since the Christian apologetics, trapped between Protestantism and the Rationalism, are gradually reduced to a row of inefficient and traditional “proofs” for the existence and kindness of God. In 1680, Nicolas Malebranche publishes the Treatise on Nature and Grace, following to explain the way in which God granted His grace to all mankind. In order to fight the skeptical thesis according to which God takes not directly part in this world, Malebranche refers the action of God to the concept of “general/divine will”. If such a theory is useful at a certain metaphysical level in explaining the presence of the evil in the world (God does not create but allows the evil, it raises some anthropological issues, especially concerning the nature of the human free will. If anything in the world emerges as a direct consequence of God’s “general will”, how can be conceived a real free human will? The theory of God’s general will generates an unexpected anthropological consequence (the dissolution of the human free will that Malebranche tries to hide it by inventing the concept of “inclination of the will”: God does not interfere (by causation with the human will, but He influences it (by inclination. Is it philosophically defensible? The aim of the article is to analyze some philosophical and methodological difficulties related to the new Malebranchist concept of “inclination of human will” in order to prove that the passage from the occasionalist theory of general will to an inquiry about the human will is quite problematic.

  15. [Imputing missing data in public health: general concepts and application to dichotomous variables].

    Science.gov (United States)

    Hernández, Gilma; Moriña, David; Navarro, Albert

    The presence of missing data in collected variables is common in health surveys, but the subsequent imputation thereof at the time of analysis is not. Working with imputed data may have certain benefits regarding the precision of the estimators and the unbiased identification of associations between variables. The imputation process is probably still little understood by many non-statisticians, who view this process as highly complex and with an uncertain goal. To clarify these questions, this note aims to provide a straightforward, non-exhaustive overview of the imputation process to enable public health researchers ascertain its strengths. All this in the context of dichotomous variables which are commonplace in public health. To illustrate these concepts, an example in which missing data is handled by means of simple and multiple imputation is introduced. Copyright © 2017 SESPAS. Publicado por Elsevier España, S.L.U. All rights reserved.

  16. Generalization of the Wide-Sense Markov Concept to a Widely Linear Processing

    International Nuclear Information System (INIS)

    Espinosa-Pulido, Juan Antonio; Navarro-Moreno, Jesús; Fernández-Alcalá, Rosa María; Ruiz-Molina, Juan Carlos; Oya-Lechuga, Antonia; Ruiz-Fuentes, Nuria

    2014-01-01

    In this paper we show that the classical definition and the associated characterizations of wide-sense Markov (WSM) signals are not valid for improper complex signals. For that, we propose an extension of the concept of WSM to a widely linear (WL) setting and the study of new characterizations. Specifically, we introduce a new class of signals, called widely linear Markov (WLM) signals, and we analyze some of their properties based either on second-order properties or on state-space models from a WL processing standpoint. The study is performed in both the forwards and backwards directions of time. Thus, we provide two forwards and backwards Markovian representations for WLM signals. Finally, different estimation recursive algorithms are obtained for these models

  17. Factor structure and internal consistency of the 12-item General Health Questionnaire (GHQ-12 and the Subjective Vitality Scale (VS, and the relationship between them: a study from France

    Directory of Open Access Journals (Sweden)

    Ismaïl Amany

    2009-03-01

    Full Text Available Abstract Background The objectives of this study were to test the factor structure and internal consistency of the 12-item General Health Questionnaire (GHQ-12 and the Subjective Vitality Scale (VS in elderly French people, and to test the relationship between these two questionnaires. Methods Using a standard 'forward-backward' translation procedure, the English language versions of the two instruments (i.e. the 12-item General Health Questionnaire and the Subjective Vitality Scale were translated into French. A sample of adults aged 58–72 years then completed both questionnaires. Internal consistency was assessed by Cronbach's alpha coefficient. The factor structures of the two instruments were extracted by confirmatory factor analysis (CFA. Finally, the relationship between the two instruments was assessed by correlation analysis. Results In all, 217 elderly adults participated in the study. The mean age of the respondents was 61.7 (SD = 6.2 years. The mean GHQ-12 score was 17.4 (SD = 8.0, and analysis showed satisfactory internal consistency (Cronbach's alpha coefficient = 0.78. The mean VS score was 22.4 (SD = 7.4 and its internal consistency was found to be good (Cronbach's alpha coefficient = 0.83. While CFA showed that the VS was uni-dimensional, analysis for the GHQ-12 demonstrated a good fit not only to the two-factor model (positive vs. negative items but also to a three-factor model. As expected, there was a strong and significant negative correlation between the GHQ-12 and the VS (r = -0.71, P Conclusion The results showed that the French versions of the 12-item General Health Questionnaire (GHQ-12 and the Subjective Vitality Scale (VS are reliable measures of psychological distress and vitality. They also confirm a significant negative correlation between these two instruments, lending support to their convergent validity in an elderly French population. The findings indicate that both measures have good structural

  18. Description of Allied-General Nuclear Services on-site solid waste storage concepts

    International Nuclear Information System (INIS)

    Sumner, W.B.; Thomas, L.L.

    1979-01-01

    AGNS will divide the majority of the contaminated solid waste generated during reprocessing of commercial spent nuclear reactor fuels into three categories: spent fuel cladding hulls, high-level general process trash (HLGPT) and low-level general process trash (LLGPT). The LLGPT will be stored in cargo containers identical to those used for road, rail, and sea transport. As these cargo containers are filled, they will be covered with earth for protection from natural phenomenon. The cargo containers will be sufficiently monitored to allow detection and recovery of any radionuclides before they reach the environment. The hulls and HLGPT will be stored in caissons within separate engineered soil berms. The caissons will be lined and capped to provide sufficient protection from natural phenomenon. The berms will include impervious clay layers at the bottom to prevent the downward movement of radionuclides and will be provided with sufficient monitoring to allow detection and recovery of radioactivity before it reaches the environment

  19. Struggling for clarity : cultural context, gender and a concept of depression in general practice

    OpenAIRE

    Lehti, Arja

    2009-01-01

    Many depressed patients attend primary health care, and minority-group patients often see general practitioners for depressive symptoms. The diagnosis and classification criteria of depression and guidelines for management are based on symptoms. However,expressions of depression can vary with culture and gender but the diagnostic tools and guidelines are not adapted to gendered or cultural context and have shown to be poorly applicable in clinical practice. The purpose of this thesis was to a...

  20. The diagnostic role of gut feelings in general practice A focus group study of the concept and its determinants

    Directory of Open Access Journals (Sweden)

    van der Weijden Trudy

    2009-02-01

    Full Text Available Abstract Background General practitioners sometimes base clinical decisions on gut feelings alone, even though there is little evidence of their diagnostic and prognostic value in daily practice. Research into these aspects and the use of the concept in medical education require a practical and valid description of gut feelings. The goal of our study was therefore to describe the concept of gut feelings in general practice and to identify their main determinants Methods Qualitative research including 4 focus group discussions. A heterogeneous sample of 28 GPs. Text analysis of the focus group discussions, using a grounded theory approach. Results Gut feelings are familiar to most GPs in the Netherlands and play a substantial role in their everyday routine. The participants distinguished two types of gut feelings, a sense of reassurance and a sense of alarm. In the former case, a GP is sure about prognosis and therapy, although they may not always have a clear diagnosis in mind. A sense of alarm means that a GP has the feeling that something is wrong even though objective arguments are lacking. GPs in the focus groups experienced gut feelings as a compass in situations of uncertainty and the majority of GPs trusted this guide. We identified the main determinants of gut feelings: fitting, alerting and interfering factors, sensation, contextual knowledge, medical education, experience and personality. Conclusion The role of gut feelings in general practice has become much clearer, but we need more research into the contributions of individual determinants and into the test properties of gut feelings to make the concept suitable for medical education.

  1. Life sciences payload definition and integration study. Volume 3: Preliminary equipment item specification catalog for the carry-on laboratories. [for Spacelab

    Science.gov (United States)

    1974-01-01

    All general purpose equipment items contained in the final carry-on laboratory (COL) design concepts are described in terms of specific requirements identified for COL use, hardware status, and technical parameters such as weight, volume, power, range, and precision. Estimated costs for each item are given, along with projected development times.

  2. APL/MITRA-15, concept of a virtual memory, optimization, generalized arrays

    International Nuclear Information System (INIS)

    Nevians, Jacques

    1975-01-01

    The aim of this work was to implement of an A.P.L. interpreter on a mini computer, specifically on a MITRA 15. Main topics are about dynamic allocation of the memory with a virtual memory system. The original aspect of these two systems is based on the qualities of the language which has permitted a modular and performing programming (allocating function... function of access). A study of the optimization of a certain number of primitives has been undertaken and developed (for example the J-Vectors). Moreover, the notion of structure (generalized arrays) has been introduced by the programming of some new primitives. (author) [fr

  3. A Reliability Generalization Study on the Survey of Perceived Organizational Support: The Effects of Mean Age and Number of Items on Score Reliability

    Science.gov (United States)

    Hellman, Chan M.; Fuqua, Dale R.; Worley, Jody

    2006-01-01

    The Survey of Perceived Organizational Support (SPOS) is a unidimensional measure of the general belief held by an employee that the organization is committed to him or her, values his or her continued membership, and is generally concerned about the employee's well-being. In the interest of efficiency, researchers are often compelled to use a…

  4. An Evaluation of Automatic Control System Concepts for General Aviation Airplanes

    Science.gov (United States)

    Stewart, E. C.

    1990-01-01

    A piloted simulation study of automatic longitudinal control systems for general aviation airplanes has been conducted. These automatic control systems were designed to make the simulated airplane easy to fly for a beginning or infrequent pilot. Different control systems are presented and their characteristics are documented. In a conventional airplane control system each cockpit controller commands combinations of both the airspeed and the vertical speed. The best system in the present study decoupled the airspeed and vertical speed responses to cockpit controller inputs. An important feature of the automatic system was that neither changing flap position nor maneuvering in steeply banked turns affected either the airspeed or the vertical speed. All the pilots who flew the control system simulation were favorably impressed with the very low workload and the excellent handling qualities of the simulated airplane.

  5. Simulation of the preliminary General Electric SP-100 space reactor concept using the ATHENA computer code

    International Nuclear Information System (INIS)

    Fletcher, C.D.

    1986-01-01

    The capability to perform thermal-hydraulic analyses of a space reactor using the ATHENA computer code is demonstrated. The fast reactor, liquid-lithium coolant loops, and lithium-filled heat pipes of the preliminary General electric SP-100 design were modeled with ATHENA. Two demonstration transient calculations were performed simulating accident conditions. Calculated results are available for display using the Nuclear Plant Analyzer color graphics analysis tool in addition to traditional plots. ATHENA-calculated results appear reasonable, both for steady state full power conditions, and for the two transients. This analysis represents the first known transient thermal-hydraulic simulation using an integral space reactor system model incorporating heat pipes. 6 refs., 17 figs., 1 tab

  6. Deposition of additives onto surface of carbon materials by blending method--general conception

    International Nuclear Information System (INIS)

    Przepiorski, Jacek

    2005-01-01

    Carbon fibers loaded with potassium carbonate and with metallic copper were prepared by applying a blending method. Raw isotropic coal pitch was blended with KOH or CuBr 2 and obtained mixtures were subjected to spinning. In this way KOH and copper salt-blended fiber with uniform distribution of potassium and copper were spun. The raw fibers were exposed to stabilization with a mixture of CO 2 and air or air only through heating to 330 deg. C and next to treatment with carbon dioxide or hydrogen at higher temperatures. Electron probe micro-analysis (EPMA) analyses showed presence of potassium carbonate or metallic copper predominantly in peripheral regions of the obtained fibers. Basing on the mechanisms of potassium and copper diffusion over the carbon volume, generalized method for the deposition of additives onto surface of carbon materials is proposed

  7. [Multistep surgery for spondylosyndesis. Treatment concept of destructive spondylodiscitis in patients with reduced general condition].

    Science.gov (United States)

    Isenberg, J; Jubel, A; Hahn, U; Seifert, H; Prokop, A

    2005-02-01

    Retrospective assessment of multistage surgery in the treatment of progressive spondylodiscitis in patients with critical physical status. A total of 34 patients (mean age 58.6 years) with 37 progressive spondylodiscitis foci and destruction of one to three vertebral segments (1.9 mean) were recorded within an 8-year period. Time between first complaints and operative treatment was 3 months (mean). Preoperative health status was critically reduced in 11 patients (ASA IV) and poor general condition (ASA III) was seen in 23 patients when vital indication was seen preoperatively. Considerable systemic disease (n=31), further infection focus (n=18), and nosocomial trauma (n=5) were causally related. Spondylodiscitis was seen more frequently in the lumbar (n=20) and thoracolumbar than in the thoracic (n=10) and cervical spine (n=1). Staphylococcus aureus was detectable from operative specimens and hemoculture in 15 cases, MRSA in 6 of these. In cases of monosegmentary involvement (n=7) ventral debridement, biopsy, and application of antibiotic chains were followed by autologous interbody bone grafting in a second stage operation. In 29 cases with destruction of two (n=27) and three (n=3) segments, posterior instrumentation including laminectomy in 4 patients was completed by anterior debridement and application of antibiotic chains during a first surgical intervention. After stabilization of physical condition and having reached a macroscopically indisputable implant bed, the ventral fusion with autologous interbody bone grafting or cage in combination with a plate or internal fixation system was performed as the last of several surgical steps. No case of perioperative mortality was observed. Intensive care continued 9.1 days and hospitalization 49.5 days (mean). During a 37.6-month follow-up two late recurrences were observed. A multistep surgical procedure under protection of dorsal instrumentation can limit perioperative mortality in patients in critical general

  8. Risk in technical and scientific studies: general introduction to uncertainty management and the concept of risk

    International Nuclear Information System (INIS)

    Apostolakis, G.E.

    2004-01-01

    George Apostolakis (MIT) presented an introduction to the concept of risk and uncertainty management and their use in technical and scientific studies. He noted that Quantitative Risk Assessment (QRA) provides support to the overall treatment of a system as an integrated socio-technical system. Specifically, QRA aims to answer the questions: - What can go wrong (e.g., accident sequences or scenarios)? - How likely are these sequences or scenarios? - What are the consequences of these sequences or scenarios? The Quantitative Risk Assessment deals with two major types of uncertainty. An assessment requires a 'model of the world', and this preferably would be a deterministic model based on underlying processes. In practice, there are uncertainties in this model of the world relating to variability or randomness that cannot be accounted for directly in a deterministic model and that may require a probabilistic or aleatory model. Both deterministic and aleatory models of the world have assumptions and parameters, and there are 'state-of-knowledge' or epistemic uncertainties associated with these. Sensitivity studies or eliciting expert opinion can be used to address the uncertainties in assumptions, and the level of confidence in parameter values can be characterised using probability distributions (pdfs). Overall, the distinction between aleatory and epistemic uncertainties is not always clear, and both can be treated mathematically in the same way. Lessons on safety assessments that can be learnt from experience at nuclear power plants are that beliefs about what is important can be wrong if a risk assessment is not performed. Also, precautionary approaches are not always conservative if failure modes are not identified. Nevertheless, it is important to recognize that uncertainties will remain despite a quantitative risk assessment: e.g., is the scenario list complete, are the models accepted as reasonable, and are parameter probability distributions representative of

  9. Estimated general population control limits for unitary agents in drinking water, milk, soil, and unprocessed food items. For use in reentry decision-making

    Energy Technology Data Exchange (ETDEWEB)

    Watson, A.P.; Adams, J.D.; Cerar, R.J.; Hess, T.L.; Kistner, S.L.; Leffingwell, S.S.; MacIntosh, R.G.; Ward, J.R.

    1992-01-01

    In the event of an unplanned release of chemical agent during any stage of the Chemical Stockpile Disposal Program (CSDP), the potential exists for contamination of drinking water, forage crops, grains, garden produce, and livestock. Persistent agents such as VX or sulfur mustard pose the greatest human health concern for reentry. This White Paper has been prepared to provide technical bases for these decisions by developing working estimates of agent control limits in selected environmental media considered principal sources of potential human exposure. To date, control limits for public exposure to unitary agents have been established for atmospheric concentrations only. The current analysis builds on previous work to calculate working estimates of control limits for ingestion and dermal exposure to potentially contaminated drinking water, milk, soil, and unprocessed food items such as garden produce. Information characterizing agent desorption from, and detection on or in, contaminated porous media are presently too developed to permit reasonable estimation of dermal exposure from this source. Thus, dermal contact with potentially contaminated porous surfaces is not considered in this document.

  10. General Dental Practitioners’ Concept towards Using Radiography and Apex-Locators in Endodontics

    Science.gov (United States)

    Raoof, Maryam; Heidaripour, Maryam; Shahravan, Arash; Haghani, Jahangir; Afkham, Arash; Razifar, Mahsa; Mohammadizadeh, Sakineh

    2014-01-01

    Introduction: Despite being the gold standard as well as a routine technique in endodontics, radiographic working length (WL) determination owns many drawbacks. Electronic apex-locators (EALs) are recommended to complement radiographies. The aim of this study was to evaluate the perceptions of Iranian general dental practitioners (GDPs) towards using radiography and EAL. Methods and Materials: Three hundred and ninety one GDPs attending the 53th Iranian Dental Association Congress completed a questionnaire focusing on the use of radiography and EALs during the various stages of root canal treatment. The data was analyzed with the chi-square test with the level of significance set at 0.05. The results were then calculated as frequencies and percentages. Results: More than half of the GDPs reported using radiographs as the sole method for WL determination. A total of 30.4% of the practitioners were using the combined approach during root canal therapy of a single-rooted tooth, while 38.9% used this method in multi-rooted teeth. Approximately half of the respondents would not order follow-up radiographies after root canal treatment. Conclusion: Radiography continues to be the most common method for WL determination in Iran. PMID:25386209

  11. Simulation Study on the Application of the Generalized Entropy Concept in Artificial Neural Networks

    Directory of Open Access Journals (Sweden)

    Krzysztof Gajowniczek

    2018-04-01

    Full Text Available Artificial neural networks are currently one of the most commonly used classifiers and over the recent years they have been successfully used in many practical applications, including banking and finance, health and medicine, engineering and manufacturing. A large number of error functions have been proposed in the literature to achieve a better predictive power. However, only a few works employ Tsallis statistics, although the method itself has been successfully applied in other machine learning techniques. This paper undertakes the effort to examine the q -generalized function based on Tsallis statistics as an alternative error measure in neural networks. In order to validate different performance aspects of the proposed function and to enable identification of its strengths and weaknesses the extensive simulation was prepared based on the artificial benchmarking dataset. The results indicate that Tsallis entropy error function can be successfully introduced in the neural networks yielding satisfactory results and handling with class imbalance, noise in data or use of non-informative predictors.

  12. Photosynthesis by isolated chloroplasts. IV. General concept and comparison of three photochemical reactions

    Energy Technology Data Exchange (ETDEWEB)

    Arnon, D I; Allen, M B; Whatley, F R

    1956-01-01

    Procedures are described for the preparation of chloroplasts capable of carrying out three photochemical reactions, each representing an increasingly complex phase of photosynthesis: photolysis of water (Hill reaction), esterification of inorganic phosphate into adenosine triphosphate (photosynthetic phosphorylation) and the reduction of carbon dioxide to the level of carbohydrates with a simultaneous evolution of oxygen. The three photochemical reactions were separable by variations in the technique for preparation of chloroplasts and by differential inhibition by several reagents. Inhibition of a more complex phase of photosynthesis does not affect the simpler one which precedes it and, conversely, the inhibition of a simpler phase of photosynthesis is paralleled by an inhibition of the more complex phase which follows. Reversible inhibition of CO/sub 2/ fixation and photosynthetic phosphorylation, but not of photolysis, by sulfhydryl group inhibitors suggests that sulfhydryl compounds (enzymes, cofactors, or both) are involved in phosphorylation and CO/sub 2/ fixation, but not in the primary conversion of light into chemical energy as measured by the Hill reaction. Evidence is presented in support of the conclusion that the synthesis of ATP by green cells occurs at two distinct sites: anaerobically in chloroplasts by photosynthetic phosphorylation, and acrobically in smaller cytoplasmic particles, presumably mitochondria, by oxidative phosphorylation independent of light. A general scheme of photosynthesis by chloroplasts, consistent with these findings, is presented. 44 references, 8 figures, 4 tables.

  13. Developmental Dynamics of General and School-Subject-Specific Components of Academic Self-Concept, Academic Interest, and Academic Anxiety.

    Science.gov (United States)

    Gogol, Katarzyna; Brunner, Martin; Preckel, Franzis; Goetz, Thomas; Martin, Romain

    2016-01-01

    The present study investigated the developmental dynamics of general and subject-specific (i.e., mathematics, French, and German) components of students' academic self-concept, anxiety, and interest. To this end, the authors integrated three lines of research: (a) hierarchical and multidimensional approaches to the conceptualization of each construct, (b) longitudinal analyses of bottom-up and top-down developmental processes across hierarchical levels, and (c) developmental processes across subjects. The data stemmed from two longitudinal large-scale samples (N = 3498 and N = 3863) of students attending Grades 7 and 9 in Luxembourgish schools. Nested-factor models were applied to represent each construct at each grade level. The analyses demonstrated that several characteristics were shared across constructs. All constructs were multidimensional in nature with respect to the different subjects, showed a hierarchical organization with a general component at the apex of the hierarchy, and had a strong separation between the subject-specific components at both grade levels. Further, all constructs showed moderate differential stabilities at both the general (0.42 < r < 0.55) and subject-specific levels (0.45 < r < 0.73). Further, little evidence was found for top-down or bottom-up developmental processes. Rather, general and subject-specific components in Grade 9 proved to be primarily a function of the corresponding components in Grade 7. Finally, change in several subject-specific components could be explained by negative effects across subjects.

  14. Developmental Dynamics of General and School-Subject-Specific Components of Academic Self-Concept, Academic Interest, and Academic Anxiety

    Directory of Open Access Journals (Sweden)

    Katarzyna eGogol

    2016-03-01

    Full Text Available The present study investigated the developmental dynamics of general and subject-specific (i.e., mathematics, French, and German components of students’ academic self-concept, anxiety, and interest. To this end, the authors integrated three lines of research: (a hierarchical and multidimensional approaches to the conceptualization of each construct, (b longitudinal analyses of bottom-up and top-down developmental processes across hierarchical levels, and (c ipsative developmental processes across subjects. The data stemmed from two longitudinal large-scale samples (N = 3,498 and N = 3,863 of students attending Grades 7 and 9 in Luxembourgish schools. Nested-factor models were applied to represent each construct at each grade level. The analyses demonstrated that several characteristics were shared across constructs. All constructs were multidimensional in nature with respect to the different subjects, showed a hierarchical organization with a general component at the apex of the hierarchy, and had a strong separation between the subject-specific components at both grade levels. Further, all constructs showed moderate differential stabilities at both the general (.42 < r < .55 and subject-specific levels (.45 < r < .73. Further, little evidence was found for top-down or bottom-up developmental processes. Rather, general and subject-specific components in Grade 9 proved to be primarily a function of the corresponding components in Grade 7. Finally, change in several subject-specific components could be explained by negative, ipsative effects across subjects.

  15. Developmental Dynamics of General and School-Subject-Specific Components of Academic Self-Concept, Academic Interest, and Academic Anxiety

    Science.gov (United States)

    Gogol, Katarzyna; Brunner, Martin; Preckel, Franzis; Goetz, Thomas; Martin, Romain

    2016-01-01

    The present study investigated the developmental dynamics of general and subject-specific (i.e., mathematics, French, and German) components of students' academic self-concept, anxiety, and interest. To this end, the authors integrated three lines of research: (a) hierarchical and multidimensional approaches to the conceptualization of each construct, (b) longitudinal analyses of bottom-up and top-down developmental processes across hierarchical levels, and (c) developmental processes across subjects. The data stemmed from two longitudinal large-scale samples (N = 3498 and N = 3863) of students attending Grades 7 and 9 in Luxembourgish schools. Nested-factor models were applied to represent each construct at each grade level. The analyses demonstrated that several characteristics were shared across constructs. All constructs were multidimensional in nature with respect to the different subjects, showed a hierarchical organization with a general component at the apex of the hierarchy, and had a strong separation between the subject-specific components at both grade levels. Further, all constructs showed moderate differential stabilities at both the general (0.42 < r < 0.55) and subject-specific levels (0.45 < r < 0.73). Further, little evidence was found for top-down or bottom-up developmental processes. Rather, general and subject-specific components in Grade 9 proved to be primarily a function of the corresponding components in Grade 7. Finally, change in several subject-specific components could be explained by negative effects across subjects. PMID:27014162

  16. Long-Chain Metabolites of Vitamin E: Metabolic Activation as a General Concept for Lipid-Soluble Vitamins?

    Science.gov (United States)

    Schubert, Martin; Kluge, Stefan; Schmölz, Lisa; Wallert, Maria; Galli, Francesco; Birringer, Marc; Lorkowski, Stefan

    2018-01-12

    Vitamins E, A, D and K comprise the class of lipid-soluble vitamins. For vitamins A and D, a metabolic conversion of precursors to active metabolites has already been described. During the metabolism of vitamin E, the long-chain metabolites (LCMs) 13'-hydroxychromanol (13'-OH) and 13'-carboxychromanol (13'-COOH) are formed by oxidative modification of the side-chain. The occurrence of these metabolites in human serum indicates a physiological relevance. Indeed, effects of the LCMs on lipid metabolism, apoptosis, proliferation and inflammatory actions as well as tocopherol and xenobiotic metabolism have been shown. Interestingly, there are several parallels between the actions of the LCMs of vitamin E and the active metabolites of vitamin A and D. The recent findings that the LCMs exert effects different from that of their precursors support their putative role as regulatory metabolites. Hence, it could be proposed that the mode of action of the LCMs might be mediated by a mechanism similar to vitamin A and D metabolites. If the physiological relevance and this concept of action of the LCMs can be confirmed, a general concept of activation of lipid-soluble vitamins via their metabolites might be deduced.

  17. Picture this: The value of multiple visual representations for student learning of quantum concepts in general chemistry

    Science.gov (United States)

    Allen, Emily Christine

    Mental models for scientific learning are often defined as, "cognitive tools situated between experiments and theories" (Duschl & Grandy, 2012). In learning, these cognitive tools are used to not only take in new information, but to help problem solve in new contexts. Nancy Nersessian (2008) describes a mental model as being "[loosely] characterized as a representation of a system with interactive parts with representations of those interactions. Models can be qualitative, quantitative, and/or simulative (mental, physical, computational)" (p. 63). If conceptual parts used by the students in science education are inaccurate, then the resulting model will not be useful. Students in college general chemistry courses are presented with multiple abstract topics and often struggle to fit these parts into complete models. This is especially true for topics that are founded on quantum concepts, such as atomic structure and molecular bonding taught in college general chemistry. The objectives of this study were focused on how students use visual tools introduced during instruction to reason with atomic and molecular structure, what misconceptions may be associated with these visual tools, and how visual modeling skills may be taught to support students' use of visual tools for reasoning. The research questions for this study follow from Gilbert's (2008) theory that experts use multiple representations when reasoning and modeling a system, and Kozma and Russell's (2005) theory of representational competence levels. This study finds that as students developed greater command of their understanding of abstract quantum concepts, they spontaneously provided additional representations to describe their more sophisticated models of atomic and molecular structure during interviews. This suggests that when visual modeling with multiple representations is taught, along with the limitations of the representations, it can assist students in the development of models for reasoning about

  18. International programme on the health effects of the Chernobyl accident. Report by the Director-General. Executive Board 95. session, provisional agenda item 12

    International Nuclear Information System (INIS)

    1994-10-01

    The International Programme on the Health Effects of the Chernobyl Accident (IPHECA) have been initiated in mid-1991 following its endorsement by the Forty-fourth World Health Assembly in resolution WHA44.36. This report by the Director General outlines the progress made in the implementation of the Programme, and summarises the scientific information obtained to date on the health effects and planned future activities. The major projects under the programme include Thyroid project, Hematology project, Dosimetry and Communication Support Services, Brain Damage in utero project and Epidemiological Registry project

  19. Generalized concept for the estimation of body dose for radiation workers exposed to external #betta#-rays

    International Nuclear Information System (INIS)

    Piesch, E.; Boehm, J.; Heinzelmann, M.

    1983-01-01

    In radiation protection monitoring the need exists for an estimation of body dose due to external #betta#-rays, for instance if the #betta#-dose rate at the working area is expected to be high according to the data of source activity or room contamination, the indicated dose values of a personal dosemeter exceed the operational limit for the organ or tissue depth of interest, or a person was exposed to a significant dose. On behalf of the Federal Ministry of the Interior, Federal Republic of Germany, a guideline is now under preparation which offers a standardized concept of the estimation of #betta#-doses in personnel monitoring. The calculation models discussed here will be used as a basis for any case of external #betta#-irradiation where, in connection with the German Radiation Protection Ordinance, the ICRP dose equivalent limits are reached or the dosemeter readings are not representative for an individual exposure. The generalized concept discussed in the paper relates to: the calculation of #betta#-dose on the basis of source activity or spectral particle fluence and takes into account the special cases of point sources, area sources and volume sources; the estimation of body dose on the basis of calculated data or measured results from area or personnel monitoring, taking into account the dose equivalent in different depths of tissue, in particular the dose equivalent to the skin, the lens of the eye and other organs; and finally the estimation of skin dose due to the contamination of the skin surface. Basic reference data are presented in order to estimate the dose equivalent of interest which varies significantly in the #betta#-radiation field as a function of the maximum #betta#-energy, distance to the source, size of the source, activity per area for surface contamination and activity per volume for air contamination

  20. A study of school adjustment, self-concept, self-esteem, general wellbeing and parent child relationship in Juvenile Idiopathic Arthritis.

    Science.gov (United States)

    Yadav, Anita; Yadav, T P

    2013-03-01

    To assess school adjustment, self-concept, self-esteem, general wellbeing and parent-child relationship in children with Juvenile Idiopathic Arthritis (JIA)and to study the correlation of these parameters with chronicity of disease, number of active joints, laboratory parameters of disease activity and JIA subtypes. A total of 64 children (32 cases and 32 controls) were recruited for analysis. Self report questionnaires which included PGI General Wellbeing Measure, Adjustment Inventory for School Students, Parent Child Relationship Scale, Self Esteem Inventory and Self Concept Questionnaires were used to assess all the enrolled subjects. Cases had significantly lower general physical well being (p self-esteem, self-concept, adjustment in school, general wellbeing and evokes disturbed parent-child relationship.

  1. Neosporosis bovina: conceptos generales, inmunidad y perspectivas para la vacunación Bovine neosporosis: general concepts, immunity and perspectives for vaccination

    Directory of Open Access Journals (Sweden)

    D.P. Moore

    2005-12-01

    -abortion can occur. Resistance to the parasite is dependent on T helper cell 1 cytokine responses. This has important repercussions for pregnant female bovine because strong T helper cell 1 cytokine responses are incompatible with successful pregnancy. However, it was demonstrated that chronically infected cows develop immune mechanisms against the abortion caused by a second Neospora-exposure. The comprehension of those mechanisms is needed for the formulation of Neospora-vaccines that prevent bovine neosporosis. General concepts about neosporosis with emphasis in the immune response and perspectives for vaccination are mentioned in the present review.

  2. Overview of Classical Test Theory and Item Response Theory for Quantitative Assessment of Items in Developing Patient-Reported Outcome Measures

    Science.gov (United States)

    Cappelleri, Joseph C.; Lundy, J. Jason; Hays, Ron D.

    2014-01-01

    Introduction The U.S. Food and Drug Administration’s patient-reported outcome (PRO) guidance document defines content validity as “the extent to which the instrument measures the concept of interest” (FDA, 2009, p. 12). “Construct validity is now generally viewed as a unifying form of validity for psychological measurements, subsuming both content and criterion validity” (Strauss & Smith, 2009, p. 7). Hence both qualitative and quantitative information are essential in evaluating the validity of measures. Methods We review classical test theory and item response theory approaches to evaluating PRO measures including frequency of responses to each category of the items in a multi-item scale, the distribution of scale scores, floor and ceiling effects, the relationship between item response options and the total score, and the extent to which hypothesized “difficulty” (severity) order of items is represented by observed responses. Conclusion Classical test theory and item response theory can be useful in providing a quantitative assessment of items and scales during the content validity phase of patient-reported outcome measures. Depending on the particular type of measure and the specific circumstances, either one or both approaches should be considered to help maximize the content validity of PRO measures. PMID:24811753

  3. A study of how precursor key concepts for organic chemistry success are understood by general chemistry students

    Science.gov (United States)

    Meyer, Patrick Gerard

    This study examines college student understanding of key concepts that will support future organic chemistry success as determined by university instructors. During four one-hour individual interviews the sixteen subjects attempted to solve general chemistry problems. A think-aloud protocol was used along with a whiteboard where the students could draw and illustrate their ideas. The protocols for the interviews were adapted from the Covalent Structure and Bonding two-tiered multiple choice diagnostic instrument (Peterson, Treagust, & Garnett, 1989) and augmented by the Geometry and Polarity of Molecules single-tiered multiple choice instrument (Furio & Calatayud, 1996). The interviews were videotaped, transcribed, and coded for analysis to determine the subjects' understanding of the key ideas. The subjects displayed many misconceptions that were summarized into nine assertions about student conceptualization of chemistry. (1) Many students misunderstand the location and nature of intermolecular forces. (2) Some think electronegativity differences among atoms in a molecule are sufficient to make the molecule polar, regardless of spatial arrangement. (3) Most know that higher phase change temperatures imply stronger intermolecular attractions, but many do not understand the difference between covalent molecular and covalent network substances. (4) Many have difficulty deciding whether a molecule is polar or non-polar, often confusing bilateral symmetry with spatial symmetry in all three dimensions. (5) Many cannot reliably draw correct Lewis structures due to carelessness and overuse of flawed algorithms. (6) Many are confused by how electrons can both repel one other and facilitate bonding between atoms via orbitals---this seems oxymoronic to them. (7) Many cannot explain why the atoms of certain elements do not follow the octet rule and some believe the octet rule alone can determine the shape of a molecule. (8) Most do know that electronegativity and polarity

  4. A 67-Item Stress Resilience item bank showing high content validity was developed in a psychosomatic sample.

    Science.gov (United States)

    Obbarius, Nina; Fischer, Felix; Obbarius, Alexander; Nolte, Sandra; Liegl, Gregor; Rose, Matthias

    2018-04-10

    To develop the first item bank to measure Stress Resilience (SR) in clinical populations. Qualitative item development resulted in an initial pool of 131 items covering a broad theoretical SR concept. These items were tested in n=521 patients at a psychosomatic outpatient clinic. Exploratory and Confirmatory Factor Analysis (CFA), as well as other state-of-the-art item analyses and IRT were used for item evaluation and calibration of the final item bank. Out of the initial item pool of 131 items, we excluded 64 items (54 factor loading .3, 2 non-discriminative Item Response Curves, 4 Differential Item Functioning). The final set of 67 items indicated sufficient model fit in CFA and IRT analyses. Additionally, a 10-item short form with high measurement precision (SE≤.32 in a theta range between -1.8 and +1.5) was derived. Both the SR item bank and the SR short form were highly correlated with an existing static legacy tool (Connor-Davidson Resilience Scale). The final SR item bank and 10-item short form showed good psychometric properties. When further validated, they will be ready to be used within a framework of Computer-Adaptive Tests for a comprehensive assessment of the Stress-Construct. Copyright © 2018. Published by Elsevier Inc.

  5. The basics of item response theory using R

    CERN Document Server

    Baker, Frank B

    2017-01-01

    This graduate-level textbook is a tutorial for item response theory that covers both the basics of item response theory and the use of R for preparing graphical presentation in writings about the theory. Item response theory has become one of the most powerful tools used in test construction, yet one of the barriers to learning and applying it is the considerable amount of sophisticated computational effort required to illustrate even the simplest concepts. This text provides the reader access to the basic concepts of item response theory freed of the tedious underlying calculations. It is intended for those who possess limited knowledge of educational measurement and psychometrics. Rather than presenting the full scope of item response theory, this textbook is concise and practical and presents basic concepts without becoming enmeshed in underlying mathematical and computational complexities. Clearly written text and succinct R code allow anyone familiar with statistical concepts to explore and apply item re...

  6. The Electromagnetic Conception of Nature at the Root of the Special and General Relativity Theories and Its Revolutionary Meaning

    Science.gov (United States)

    Giannetto, Enrico R. A.

    2009-01-01

    The revolution in XX century physics, induced by relativity theories, had its roots within the electromagnetic conception of Nature. It was developed through a tradition related to Brunian and Leibnizian physics, to the German "Naturphilosophie" and English XIXth physics. The electromagnetic conception of Nature was in some way realized by the…

  7. Defining According to Its Essence: An Analysis on the Concept of Tong Shi Education (General Education) in the Native Chinese Context

    Science.gov (United States)

    Lu, Yi; Xu, Yuan

    2018-01-01

    The authors review the concept of Tong Shi (Chinese characters omitted) in ancient Chinese philosophical texts, illustrate the Chinese cultural attributes unique to the characters Tong and Shi, and confirm that the name and essence of Tong Shi Education has a clear directivity and irreplaceable coverage to university general education in…

  8. Item response theory - A first approach

    Science.gov (United States)

    Nunes, Sandra; Oliveira, Teresa; Oliveira, Amílcar

    2017-07-01

    The Item Response Theory (IRT) has become one of the most popular scoring frameworks for measurement data, frequently used in computerized adaptive testing, cognitively diagnostic assessment and test equating. According to Andrade et al. (2000), IRT can be defined as a set of mathematical models (Item Response Models - IRM) constructed to represent the probability of an individual giving the right answer to an item of a particular test. The number of Item Responsible Models available to measurement analysis has increased considerably in the last fifteen years due to increasing computer power and due to a demand for accuracy and more meaningful inferences grounded in complex data. The developments in modeling with Item Response Theory were related with developments in estimation theory, most remarkably Bayesian estimation with Markov chain Monte Carlo algorithms (Patz & Junker, 1999). The popularity of Item Response Theory has also implied numerous overviews in books and journals, and many connections between IRT and other statistical estimation procedures, such as factor analysis and structural equation modeling, have been made repeatedly (Van der Lindem & Hambleton, 1997). As stated before the Item Response Theory covers a variety of measurement models, ranging from basic one-dimensional models for dichotomously and polytomously scored items and their multidimensional analogues to models that incorporate information about cognitive sub-processes which influence the overall item response process. The aim of this work is to introduce the main concepts associated with one-dimensional models of Item Response Theory, to specify the logistic models with one, two and three parameters, to discuss some properties of these models and to present the main estimation procedures.

  9. Evolution of a Test Item

    Science.gov (United States)

    Spaan, Mary

    2007-01-01

    This article follows the development of test items (see "Language Assessment Quarterly", Volume 3 Issue 1, pp. 71-79 for the article "Test and Item Specifications Development"), beginning with a review of test and item specifications, then proceeding to writing and editing of items, pretesting and analysis, and finally selection of an item for a…

  10. Dependability of technical items: Problems of standardization

    Science.gov (United States)

    Fedotova, G. A.; Voropai, N. I.; Kovalev, G. F.

    2016-12-01

    This paper is concerned with problems blown up in the development of a new version of the Interstate Standard GOST 27.002 "Industrial product dependability. Terms and definitions". This Standard covers a wide range of technical items and is used in numerous regulations, specifications, standard and technical documentation. A currently available State Standard GOST 27.002-89 was introduced in 1990. Its development involved a participation of scientists and experts from different technical areas, its draft was debated in different audiences and constantly refined, so it was a high quality document. However, after 25 years of its application it's become necessary to develop a new version of the Standard that would reflect the current understanding of industrial dependability, accounting for the changes taking place in Russia in the production, management and development of various technical systems and facilities. The development of a new version of the Standard makes it possible to generalize on a terminological level the knowledge and experience in the area of reliability of technical items, accumulated over a quarter of the century in different industries and reliability research schools, to account for domestic and foreign experience of standardization. Working on the new version of the Standard, we have faced a number of issues and problems on harmonization with the International Standard IEC 60500-192, caused first of all by different approaches to the use of terms and differences in the mentalities of experts from different countries. The paper focuses on the problems related to the chapter "Maintenance, restoration and repair", which caused difficulties for the developers to harmonize term definitions both with experts and the International Standard, which is mainly related to differences between the Russian concept and practice of maintenance and repair and foreign ones.

  11. The Application and Evaluation of a Two-Concept Diagnostic Instrument with Students Entering College General Chemistry

    Science.gov (United States)

    Heredia, Keily; Xu, Xiaoying; Lewis, Jennifer E.

    2012-01-01

    The Particulate Nature of Matter and Chemical Bonding Diagnostic Instrument (Othman J., Treagust D. F. and Chandrasegaran A. L., (2008), "Int. J. Sci. Educ.," 30(11), 1531-1550) is used to investigate college students' understanding of two chemistry concepts: particulate nature of matter and chemical bonding. The instrument, originally…

  12. Introduction to some fundamental concepts of general relativity and to their required use in some modern timekeeping systems

    Science.gov (United States)

    Alley, C. O.

    1982-01-01

    Einstein's theory of gravity as curved space-time is presented. Emphasis is on the physical concepts, using only elementary mathematics. For the slow motions and weak gravitational fields experienced on Earth, the main curvature is that of time, not space. Experiments demonstrating this property are reviewed. The fundamental effects of motion and gravitational potential on clocks in many practical situations are discussed.

  13. Analyzing General Chemistry Texts' Treatment of Rates of Change Concepts in Reaction Kinetics Reveals Missing Conceptual Links

    Science.gov (United States)

    Seethaler, Sherry; Czworkowski, John; Wynn, Lynda

    2018-01-01

    Change over time is a crosscutting theme in the sciences that is pivotal to reaction kinetics, an anchoring concept in undergraduate chemistry, and students' struggles with rates of change are well-documented. Informed by the education scholarship in chemistry, physics, and mathematics, a research team with members from complementary disciplinary…

  14. Questionário de Saúde Geral (QSG-12: o efeito de itens negativos em sua estrutura fatorial General Health Questionnaire (GHQ-12: the effect of negative items in its factorial structure

    Directory of Open Access Journals (Sweden)

    Valdiney V. Gouveia

    2012-02-01

    Full Text Available O Questionário de Saúde Geral (QSG-12 detecta doenças psiquiátricas não severas. Embora comumente tratado como um índice geral, a definição de sua estrutura fatorial suscita debates. Este trabalho objetivou testar tal estrutura, comparando três modelos: dois frequentemente citados na literatura (uni e bifatorial e um terceiro, também unifatorial, que controla o viés de resposta devido à redação dos itens. Participaram 1.180 pessoas (300 estudantes universitários; 311 policiais militares; 274 professores do ensino fundamental; e 295 membros da população em geral, que responderam ao QSG-12 e perguntas demográficas. Análises fatoriais confirmatórias apontaram que a estrutura unifatorial, controlando o efeito dos itens negativos, reuniu os melhores índices de ajuste, excetuando entre os militares. Essa estrutura apresentou consistência interna superior a 0,80 em todos os grupos. Concluiu-se que o QSG-12 é mais adequado como unifatorial, embora se indique a necessidade de estudos futuros com pessoas de profissões e níveis de saúde mental diferentes.The General Health Questionnaire (GHQ-12 detects non severe psychiatric illnesses. Although commonly treated as a general index, the definition of its factorial structure is cause for debate. This study aimed to test this structure comparing three models: two frequently cited in the literature (one- and t bi- factorial and a third, also one-factor, which controls response bias due to the negative wording of items. A total of 1,180 people participated (300 undergraduates, 311 military policemen, 274 elementary school teachers and 295 members of the general population answering the GHQ-12 and demographic questions. Confirmatory factor analyses showed that the one-factor structure, controlling by the wording effect, gathered the best fit indexes, except among the military. This structure showed greater than0.80 reliability in all groups. It was concluded that the one-factor model of

  15. Writing, Evaluating and Assessing Data Response Items in Economics.

    Science.gov (United States)

    Trotman-Dickenson, D. I.

    1989-01-01

    Describes some of the problems in writing data response items in economics for use by A Level and General Certificate of Secondary Education (GCSE) students. Examines the experience of two series of workshops on writing items, evaluating them and assessing responses from schools. Offers suggestions for producing packages of data response items as…

  16. Policy for the treatment of insulting and sensitive lexical items in the ...

    African Journals Online (AJOL)

    Keywords: policy, treatment, insulting lexical items, sensitive lexical items, dictionary, woordeboek van die afrikaanse taal, simplexes, compounds, expressions, general usage criterion, labelling, synonyms, metalanguage, collocations, editorial usage examples, citations, advisors, racist lexical items, neutral lemmas, ...

  17. New Concepts of Quality Assurance in Analytical Chemistry: Will They Influence the Way We Conduct Science in General?

    DEFF Research Database (Denmark)

    Andersen, Jens; Glasdam, Sidsel-Marie; Larsen, Daniel Bo

    2016-01-01

    , but in contemporary science two approaches to the implementation of statistics in decision making are used: 1. Short-term precision and 2. long-term precision. Both approaches are valid and both are described using the same methods of statistics. However, they lead to completely different conclusions and decisions....... Despite good intentions and new concepts, as well as practices and procedures for quality assurance, it is shown by these two examples that these efforts may be inadequate or mislead scientists into making major mistakes in the decision-making process. A set of equations is supplied, which are based......According to the guide Vocabulary in Metrology (VIM3) (JCGM, 2008), the definition of the concepts of trueness and accuracy has been revised, which has an important impact on analytical chemistry. Additionally, Eurachem/CITAC has published a new edition of the guide to Quantifying Uncertainty...

  18. SHIPPING OF RADIOACTIVE ITEMS

    CERN Multimedia

    TIS/RP Group

    2001-01-01

    The TIS-RP group informs users that shipping of small radioactive items is normally guaranteed within 24 hours from the time the material is handed in at the TIS-RP service. This time is imposed by the necessary procedures (identification of the radionuclides, determination of dose rate and massive objects require a longer procedure and will therefore take longer.

  19. Spare Items validation

    International Nuclear Information System (INIS)

    Fernandez Carratala, L.

    1998-01-01

    There is an increasing difficulty for purchasing safety related spare items, with certifications by manufacturers for maintaining the original qualifications of the equipment of destination. The main reasons are, on the top of the logical evolution of technology, applied to the new manufactured components, the quitting of nuclear specific production lines and the evolution of manufacturers quality systems, originally based on nuclear codes and standards, to conventional industry standards. To face this problem, for many years different Dedication processes have been implemented to verify whether a commercial grade element is acceptable to be used in safety related applications. In the same way, due to our particular position regarding the spare part supplies, mainly from markets others than the american, C.N. Trillo has developed a methodology called Spare Items Validation. This methodology, which is originally based on dedication processes, is not a single process but a group of coordinated processes involving engineering, quality and management activities. These are to be performed on the spare item itself, its design control, its fabrication and its supply for allowing its use in destinations with specific requirements. The scope of application is not only focussed on safety related items, but also to complex design, high cost or plant reliability related components. The implementation in C.N. Trillo has been mainly curried out by merging, modifying and making the most of processes and activities which were already being performed in the company. (Author)

  20. Selecting Lower Priced Items.

    Science.gov (United States)

    Kleinert, Harold L.; And Others

    1988-01-01

    A program used to teach moderately to severely mentally handicapped students to select the lower priced items in actual shopping activities is described. Through a five-phase process, students are taught to compare prices themselves as well as take into consideration variations in the sizes of containers and varying product weights. (VW)

  1. The Role of Item Models in Automatic Item Generation

    Science.gov (United States)

    Gierl, Mark J.; Lai, Hollis

    2012-01-01

    Automatic item generation represents a relatively new but rapidly evolving research area where cognitive and psychometric theories are used to produce tests that include items generated using computer technology. Automatic item generation requires two steps. First, test development specialists create item models, which are comparable to templates…

  2. Item information and discrimination functions for trinary PCM items

    NARCIS (Netherlands)

    Akkermans, Wies; Muraki, Eiji

    1997-01-01

    For trinary partial credit items the shape of the item information and the item discrimination function is examined in relation to the item parameters. In particular, it is shown that these functions are unimodal if δ2 – δ1 < 4 ln 2 and bimodal otherwise. The locations and values of the maxima are

  3. Designing a Virtual Item Bank Based on the Techniques of Image Processing

    Science.gov (United States)

    Liao, Wen-Wei; Ho, Rong-Guey

    2011-01-01

    One of the major weaknesses of the item exposure rates of figural items in Intelligence Quotient (IQ) tests lies in its inaccuracies. In this study, a new approach is proposed and a useful test tool known as the Virtual Item Bank (VIB) is introduced. The VIB combine Automatic Item Generation theory and image processing theory with the concepts of…

  4. ANALYSIS OF THE CONCEPT OF THE PRINCIPLES GENERALLY ACCEPTED ACCOUNTING OF UNITED STATES OF AMERICA (FASB RULES)

    OpenAIRE

    Vílchez Olivares, Percy Antonio

    2014-01-01

    The Framework for the preparation and presentation of financial statements is a statement that directs and informs the accounting principles generally accepted in the United States (U.S. GAAP), which in turn is valid in our country, on the application to determine the accounting principles generally accepted in Peru, in its supplementary nature as established by Resolution No. 013-98 Accounting Standards Council, an organ of the Public Accounts of the Nation. The Framework is the backbone of ...

  5. Conception and syllabus on radiochemistry and radioecology principles for general student groups of a university chemical department

    International Nuclear Information System (INIS)

    Bogdanov, R.V.

    1994-01-01

    The problem of basic principles of selecting materials for general courses on diverse subjects in chemical science is discussed. Relying on certain general rules and proceeding from specificity of radiochemistry, the author suggests a variant of syllabus including radiochemical and radioecological blocks intented for 48 academic hours. In methodical respect emphasis is made on theoretical material presentation in close combination with various nuclear methods used in chemical studies. 6 refs., 1 fig

  6. The collaboration of general practitioners and nurses in primary care: a comparative analysis of concepts and practices in Slovenia and Spain.

    Science.gov (United States)

    Hämel, Kerstin; Vössing, Carina

    2017-09-01

    Aim A comparative analysis of concepts and practices of GP-nurse collaborations in primary health centres in Slovenia and Spain. Cross-professional collaboration is considered a key element for providing high-quality comprehensive care by combining the expertise of various professions. In many countries, nurses are also being given new and more extensive responsibilities. Implemented concepts of collaborative care need to be analysed within the context of care concepts, organisational structures, and effective collaboration. Background review of primary care concepts (literature analysis, expert interviews), and evaluation of collaboration in 'best practice' health centres in certain regions of Slovenia and Spain. Qualitative content analysis of expert interviews, presentations, observations, and group discussions with professionals and health centre managers. Findings In Slovenian health centres, the collaboration between GPs and nurses has been strongly shaped by their organisation in separate care units and predominantly case-oriented functions. Conventional power structures between professions hinder effective collaboration. The introduction of a new cross-professional primary care concept has integrated advanced practice nurses into general practice. Conventional hierarchies still exist, but a shared vision of preventive care is gradually strengthening attitudes towards team-oriented care. Formal regulations or incentives for teamwork have yet to be implemented. In Spain, health centres were established along with a team-based care concept that encompasses close physician-nurse collaboration and an autonomous role for nurses in the care process. Nurses collaborate with GPs on more equal terms with conflicts centring on professional disagreements. Team development structures and financial incentives for team achievements have been implemented, encouraging teams to generate their own strategies to improve teamwork. Clearly defined structures, shared visions of

  7. Item Banking with Embedded Standards

    Science.gov (United States)

    MacCann, Robert G.; Stanley, Gordon

    2009-01-01

    An item banking method that does not use Item Response Theory (IRT) is described. This method provides a comparable grading system across schools that would be suitable for low-stakes testing. It uses the Angoff standard-setting method to obtain item ratings that are stored with each item. An example of such a grading system is given, showing how…

  8. Creating a Database for Test Items in National Examinations (pp ...

    African Journals Online (AJOL)

    Nekky Umera

    different programmers create files and application programs over a long period. .... In theory or essay questions, alternative methods of solving problems are explored and ... Unworthy items are those that do not focus on the central concept or.

  9. New decision criteria for selecting delta check methods based on the ratio of the delta difference to the width of the reference range can be generally applicable for each clinical chemistry test item.

    Science.gov (United States)

    Park, Sang Hyuk; Kim, So-Young; Lee, Woochang; Chun, Sail; Min, Won-Ki

    2012-09-01

    Many laboratories use 4 delta check methods: delta difference, delta percent change, rate difference, and rate percent change. However, guidelines regarding decision criteria for selecting delta check methods have not yet been provided. We present new decision criteria for selecting delta check methods for each clinical chemistry test item. We collected 811,920 and 669,750 paired (present and previous) test results for 27 clinical chemistry test items from inpatients and outpatients, respectively. We devised new decision criteria for the selection of delta check methods based on the ratio of the delta difference to the width of the reference range (DD/RR). Delta check methods based on these criteria were compared with those based on the CV% of the absolute delta difference (ADD) as well as those reported in 2 previous studies. The delta check methods suggested by new decision criteria based on the DD/RR ratio corresponded well with those based on the CV% of the ADD except for only 2 items each in inpatients and outpatients. Delta check methods based on the DD/RR ratio also corresponded with those suggested in the 2 previous studies, except for 1 and 7 items in inpatients and outpatients, respectively. The DD/RR method appears to yield more feasible and intuitive selection criteria and can easily explain changes in the results by reflecting both the biological variation of the test item and the clinical characteristics of patients in each laboratory. We suggest this as a measure to determine delta check methods.

  10. Convergent Time-Varying Regression Models for Data Streams: Tracking Concept Drift by the Recursive Parzen-Based Generalized Regression Neural Networks.

    Science.gov (United States)

    Duda, Piotr; Jaworski, Maciej; Rutkowski, Leszek

    2018-03-01

    One of the greatest challenges in data mining is related to processing and analysis of massive data streams. Contrary to traditional static data mining problems, data streams require that each element is processed only once, the amount of allocated memory is constant and the models incorporate changes of investigated streams. A vast majority of available methods have been developed for data stream classification and only a few of them attempted to solve regression problems, using various heuristic approaches. In this paper, we develop mathematically justified regression models working in a time-varying environment. More specifically, we study incremental versions of generalized regression neural networks, called IGRNNs, and we prove their tracking properties - weak (in probability) and strong (with probability one) convergence assuming various concept drift scenarios. First, we present the IGRNNs, based on the Parzen kernels, for modeling stationary systems under nonstationary noise. Next, we extend our approach to modeling time-varying systems under nonstationary noise. We present several types of concept drifts to be handled by our approach in such a way that weak and strong convergence holds under certain conditions. Finally, in the series of simulations, we compare our method with commonly used heuristic approaches, based on forgetting mechanism or sliding windows, to deal with concept drift. Finally, we apply our concept in a real life scenario solving the problem of currency exchange rates prediction.

  11. Concept - or no concept

    DEFF Research Database (Denmark)

    Thorsteinsson, Uffe

    1999-01-01

    Discussion about concept in industrial companies. A method for mapping of managerial concept in specific area is shown......Discussion about concept in industrial companies. A method for mapping of managerial concept in specific area is shown...

  12. Language-related differential item functioning between English and German PROMIS Depression items is negligible.

    Science.gov (United States)

    Fischer, H Felix; Wahl, Inka; Nolte, Sandra; Liegl, Gregor; Brähler, Elmar; Löwe, Bernd; Rose, Matthias

    2017-12-01

    To investigate differential item functioning (DIF) of PROMIS Depression items between US and German samples we compared data from the US PROMIS calibration sample (n = 780), a German general population survey (n = 2,500) and a German clinical sample (n = 621). DIF was assessed in an ordinal logistic regression framework, with 0.02 as criterion for R 2 -change and 0.096 for Raju's non-compensatory DIF. Item parameters were initially fixed to the PROMIS Depression metric; we used plausible values to account for uncertainty in depression estimates. Only four items showed DIF. Accounting for DIF led to negligible effects for the full item bank as well as a post hoc simulated computer-adaptive test (German general population sample was considerably lower compared to the US reference value of 50. Overall, we found little evidence for language DIF between US and German samples, which could be addressed by either replacing the DIF items by items not showing DIF or by scoring the short form in German samples with the corrected item parameters reported. Copyright © 2016 John Wiley & Sons, Ltd.

  13. SHIPPING OF RADIOACTIVE ITEMS

    CERN Multimedia

    TIS/RP Group

    2001-01-01

    The TIS-RP group informs users that shipping of small radioactive items is normally guaranteed within 24 hours from the time the material is handed in at the TIS-RP service. This time is imposed by the necessary procedures (identification of the radionuclides, determination of dose rate, preparation of the package and related paperwork). Large and massive objects require a longer procedure and will therefore take longer.

  14. Guide to good practices for the development of test items

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-01-01

    While the methodology used in developing test items can vary significantly, to ensure quality examinations, test items should be developed systematically. Test design and development is discussed in the DOE Guide to Good Practices for Design, Development, and Implementation of Examinations. This guide is intended to be a supplement by providing more detailed guidance on the development of specific test items. This guide addresses the development of written examination test items primarily. However, many of the concepts also apply to oral examinations, both in the classroom and on the job. This guide is intended to be used as guidance for the classroom and laboratory instructor or curriculum developer responsible for the construction of individual test items. This document focuses on written test items, but includes information relative to open-reference (open book) examination test items, as well. These test items have been categorized as short-answer, multiple-choice, or essay. Each test item format is described, examples are provided, and a procedure for development is included. The appendices provide examples for writing test items, a test item development form, and examples of various test item formats.

  15. Algorithms for the Construction of Parallel Tests by Zero-One Programming. Project Psychometric Aspects of Item Banking No. 7. Research Report 86-7.

    Science.gov (United States)

    Boekkooi-Timminga, Ellen

    Nine methods for automated test construction are described. All are based on the concepts of information from item response theory. Two general kinds of methods for the construction of parallel tests are presented: (1) sequential test design; and (2) simultaneous test design. Sequential design implies that the tests are constructed one after the…

  16. Medical Students’ View about the Effects of Practical Courses on Learning the General Theoretical Concepts of Basic Medical Sciences

    OpenAIRE

    Leila Roshangar; Fariba Salek Ranjbarzadeh; Reza Piri; Mahdi Karimi Shoar; Leila Rasi Marzabadi

    2014-01-01

    Introduction: The basic medical sciences section requires 2.5 years in the medical education curriculum. Practical courses complement theoretical knowledge in this period to improve their appreciation. Despite spending lots of disbursement and time, this period’s efficacy is not clearly known. Methods: One hundred thirty-three General Practitioner (GP) students have been included in this descriptive cross-sectional study and were asked by questionnaire about the positive impact of practical c...

  17. The general principles and consequences of environmental radiation exposure in relation to Canada's nuclear fuel waste management concept

    International Nuclear Information System (INIS)

    Myers, D.K.

    1989-09-01

    This document reviews the general principles and biological consequences of environmental radiation exposure. Particular attention was paid to the ICRP principle that if individual humans are adequately protected, then populations of other living organisms are likely to be sufficiently protected. The data reviewed in this document suggest that this principle is usually valid, although some theoretical concerns were noted with respect to effects of bioaccumulation of certain radionuclides in aquatic organisms

  18. Negative effects of item repetition on source memory.

    Science.gov (United States)

    Kim, Kyungmi; Yi, Do-Joon; Raye, Carol L; Johnson, Marcia K

    2012-08-01

    In the present study, we explored how item repetition affects source memory for new item-feature associations (picture-location or picture-color). We presented line drawings varying numbers of times in Phase 1. In Phase 2, each drawing was presented once with a critical new feature. In Phase 3, we tested memory for the new source feature of each item from Phase 2. Experiments 1 and 2 demonstrated and replicated the negative effects of item repetition on incidental source memory. Prior item repetition also had a negative effect on source memory when different source dimensions were used in Phases 1 and 2 (Experiment 3) and when participants were explicitly instructed to learn source information in Phase 2 (Experiments 4 and 5). Importantly, when the order between Phases 1 and 2 was reversed, such that item repetition occurred after the encoding of critical item-source combinations, item repetition no longer affected source memory (Experiment 6). Overall, our findings did not support predictions based on item predifferentiation, within-dimension source interference, or general interference from multiple traces of an item. Rather, the findings were consistent with the idea that prior item repetition reduces attention to subsequent presentations of the item, decreasing the likelihood that critical item-source associations will be encoded.

  19. Social phobia, anxiety, oppositional behavior, social skills, and self-concept in children with specific selective mutism, generalized selective mutism, and community controls.

    Science.gov (United States)

    Cunningham, Charles E; McHolm, Angela E; Boyle, Michael H

    2006-08-01

    We compared social phobia, anxiety, oppositional behavior, social skills, and self-concept in three groups: (1) 28 children with specific mutism (who did not speak to teachers but were more likely to speak to parents and peers at home and school); (2) 30 children with generalized mutism (whose speaking was restricted primarily to their homes); and (3) 52 community controls. Children with generalized mutism evidenced higher anxiety at school, and more separation anxiety, OCD, and depressive symptoms at home. Parents and teachers reported that the social phobia and anxiety scores of children in both the specific and generalized mutism subgroups were higher than controls. Children in both the specific and generalized mutism groups evidenced greater deficits in verbal and nonverbal social skills at home and school than controls. Teachers and parents did not report differences in nonverbal measures of social cooperation and conflict resolution and we found no evidence that selective mutism was linked to an increase in externalizing problems such as oppositional behavior or ADHD. Although children with specific mutism speak in a wider range of situations and appear less anxious to their teachers than children with generalized mutism, significant socially phobic behavior and social skills deficits are present in both groups.

  20. Gender-Based Differential Item Performance in Mathematics Achievement Items.

    Science.gov (United States)

    Doolittle, Allen E.; Cleary, T. Anne

    1987-01-01

    Eight randomly equivalent samples of high school seniors were each given a unique form of the ACT Assessment Mathematics Usage Test (ACTM). Signed measures of differential item performance (DIP) were obtained for each item in the eight ACTM forms. DIP estimates were analyzed and a significant item category effect was found. (Author/LMO)

  1. Efficient Algorithms for Segmentation of Item-Set Time Series

    Science.gov (United States)

    Chundi, Parvathi; Rosenkrantz, Daniel J.

    We propose a special type of time series, which we call an item-set time series, to facilitate the temporal analysis of software version histories, email logs, stock market data, etc. In an item-set time series, each observed data value is a set of discrete items. We formalize the concept of an item-set time series and present efficient algorithms for segmenting a given item-set time series. Segmentation of a time series partitions the time series into a sequence of segments where each segment is constructed by combining consecutive time points of the time series. Each segment is associated with an item set that is computed from the item sets of the time points in that segment, using a function which we call a measure function. We then define a concept called the segment difference, which measures the difference between the item set of a segment and the item sets of the time points in that segment. The segment difference values are required to construct an optimal segmentation of the time series. We describe novel and efficient algorithms to compute segment difference values for each of the measure functions described in the paper. We outline a dynamic programming based scheme to construct an optimal segmentation of the given item-set time series. We use the item-set time series segmentation techniques to analyze the temporal content of three different data sets—Enron email, stock market data, and a synthetic data set. The experimental results show that an optimal segmentation of item-set time series data captures much more temporal content than a segmentation constructed based on the number of time points in each segment, without examining the item set data at the time points, and can be used to analyze different types of temporal data.

  2. Item-focussed Trees for the Identification of Items in Differential Item Functioning.

    Science.gov (United States)

    Tutz, Gerhard; Berger, Moritz

    2016-09-01

    A novel method for the identification of differential item functioning (DIF) by means of recursive partitioning techniques is proposed. We assume an extension of the Rasch model that allows for DIF being induced by an arbitrary number of covariates for each item. Recursive partitioning on the item level results in one tree for each item and leads to simultaneous selection of items and variables that induce DIF. For each item, it is possible to detect groups of subjects with different item difficulties, defined by combinations of characteristics that are not pre-specified. The way a DIF item is determined by covariates is visualized in a small tree and therefore easily accessible. An algorithm is proposed that is based on permutation tests. Various simulation studies, including the comparison with traditional approaches to identify items with DIF, show the applicability and the competitive performance of the method. Two applications illustrate the usefulness and the advantages of the new method.

  3. The 12-item World Health Organization Disability Assessment Schedule II (WHO-DAS II: a nonparametric item response analysis

    Directory of Open Access Journals (Sweden)

    Fernandez Ana

    2010-05-01

    Full Text Available Abstract Background Previous studies have analyzed the psychometric properties of the World Health Organization Disability Assessment Schedule II (WHO-DAS II using classical omnibus measures of scale quality. These analyses are sample dependent and do not model item responses as a function of the underlying trait level. The main objective of this study was to examine the effectiveness of the WHO-DAS II items and their options in discriminating between changes in the underlying disability level by means of item response analyses. We also explored differential item functioning (DIF in men and women. Methods The participants were 3615 adult general practice patients from 17 regions of Spain, with a first diagnosed major depressive episode. The 12-item WHO-DAS II was administered by the general practitioners during the consultation. We used a non-parametric item response method (Kernel-Smoothing implemented with the TestGraf software to examine the effectiveness of each item (item characteristic curves and their options (option characteristic curves in discriminating between changes in the underliying disability level. We examined composite DIF to know whether women had a higher probability than men of endorsing each item. Results Item response analyses indicated that the twelve items forming the WHO-DAS II perform very well. All items were determined to provide good discrimination across varying standardized levels of the trait. The items also had option characteristic curves that showed good discrimination, given that each increasing option became more likely than the previous as a function of increasing trait level. No gender-related DIF was found on any of the items. Conclusions All WHO-DAS II items were very good at assessing overall disability. Our results supported the appropriateness of the weights assigned to response option categories and showed an absence of gender differences in item functioning.

  4. KEY ISSUES OF CONCEPTS' FORMATION OF THE NETWORK OF RESOURCE CENTER OF DISTANCE EDUCATION OF GENERAL EDUCATION INSTITUTIONS

    Directory of Open Access Journals (Sweden)

    Yuriy M. Bogachkov

    2013-06-01

    Full Text Available In the article the problem of constructing a network of resource centers for Distance Education to meet the needs of general secondary schools is presented. Modern educational trends in the use of Internet services in education are viewed.  Main contradictions, solution of which helps to create a network of resource centers, are identified. The definition of key terms related to the range of issues are given. The basic categories of participants, who  implementation of e-learning and networking are oriented on. There are considered the basic tasks of  distance education resource centers' functioning and types of supporting: personnel, regulatory, informative, systematic and  technical etc. The review of possible models of implementation of  students' distance education is reviewed . Three options for business models of resource centers, depending on funding  sources are offered.

  5. Medical Students’ View about the Effects of Practical Courses on Learning the General Theoretical Concepts of Basic Medical Sciences

    Directory of Open Access Journals (Sweden)

    Leila Roshangar

    2014-05-01

    Full Text Available Introduction: The basic medical sciences section requires 2.5 years in the medical education curriculum. Practical courses complement theoretical knowledge in this period to improve their appreciation. Despite spending lots of disbursement and time, this period’s efficacy is not clearly known. Methods: One hundred thirty-three General Practitioner (GP students have been included in this descriptive cross-sectional study and were asked by questionnaire about the positive impact of practical courses on learning theoretical knowledge. Data were analyzed by descriptive statistics. Result: The agreement in “Practical Head and Neck Anatomy” was 40.91% ± 29.45, in “Practical Trunk Anatomy” was 63.62% ± 2.32 and in “Practical Anatomy of Extremities” was 56.16% ± 2.57. In “Practical Histology”, agreement was 69.50%±2.19; “Practical Biophysics” was 45.97%±2.25, “Practical Physiology” 61.75%±2.17; “Practical Biochemistry” 36.28%±2.42; “Practical Pathology” 59.80%±2.53; “Practical Immunology” 56.25%±26.40; “Practical Microbiology and Virology” 60.39%±2.27 and “Practical Mycology and Parasitology” 68.2%± 2.16.Conclusion: GP students in Tabriz University of Medical Sciences are not optimistic about the applicability of practical courses of basic medical sciences lessons.

  6. Generalized Superconductivity. Generalized Levitation

    International Nuclear Information System (INIS)

    Ciobanu, B.; Agop, M.

    2004-01-01

    In the recent papers, the gravitational superconductivity is described. We introduce the concept of generalized superconductivity observing that any nongeodesic motion and, in particular, the motion in an electromagnetic field, can be transformed in a geodesic motion by a suitable choice of the connection. In the present paper, the gravitoelectromagnetic London equations have been obtained from the generalized Helmholtz vortex theorem using the generalized local equivalence principle. In this context, the gravitoelectromagnetic Meissner effect and, implicitly, the gravitoelectromagnetic levitation are given. (authors)

  7. 大型教育調查研究中的差別試題功能:次級分析中的核心概念及建模方法 Differential Item Functioning Analyses in Large-Scale Educational Surveys: Key Concepts and Modeling Approaches for Secondary Analysts

    Directory of Open Access Journals (Sweden)

    朱小姝 Xiao-Shu Zhu

    2011-03-01

    Full Text Available 大型教育評量研究常採用多階段抽樣的設計(multi-stage sampling design),透過對母群體之抽樣單位進行分層以抽取受測者。此外,還會採用複雜題本設計(complex booklet design)的方式將題目組成多份測驗題本。在此情況下,欲確保公正測量出不同受測群體的能力,關鍵在於能夠有效偵測所採用的題目是否具差別試題功能(differential item functioning, DIF)。本文旨在介紹探討在大型教育評量複雜設計之下能用以偵測差別試題功能的建模方法,並應用六種可用於偵測DIF 的多階層廣義線性模式(hierarchical generalized linear models, HGLMs),再透過電腦模擬比較它們偵測DIF 的效力。接著又將這些模式應用到國際數學與科學教育成就趨勢調查研究(TIMSS)的實證數據上,藉以探測是否存在一致性的性別DIF(uniform gender DIF)。 Many educational surveys employ a multi-stage sampling design for students, which makes use of stratification and/or clustering of population units, as well as a complex booklet design for items from an item pool. In these surveys, the reliable detection of item bias or differential item functioning (DIF across student groups is a key component for ensuring fair representations of different student groups. In this paper, we describe several modeling approaches that can be useful for detecting DIF in educational surveys. We illustrate the key ideas by investigating the performance of six hierarchical generalized linear models (HGLMs using a small simulation study and by applying them to real data from the Trends in Mathematics and Science Study (TIMSS study where we use them to investigate potential uniform gender DIF.

  8. Overview of classical test theory and item response theory for the quantitative assessment of items in developing patient-reported outcomes measures.

    Science.gov (United States)

    Cappelleri, Joseph C; Jason Lundy, J; Hays, Ron D

    2014-05-01

    The US Food and Drug Administration's guidance for industry document on patient-reported outcomes (PRO) defines content validity as "the extent to which the instrument measures the concept of interest" (FDA, 2009, p. 12). According to Strauss and Smith (2009), construct validity "is now generally viewed as a unifying form of validity for psychological measurements, subsuming both content and criterion validity" (p. 7). Hence, both qualitative and quantitative information are essential in evaluating the validity of measures. We review classical test theory and item response theory (IRT) approaches to evaluating PRO measures, including frequency of responses to each category of the items in a multi-item scale, the distribution of scale scores, floor and ceiling effects, the relationship between item response options and the total score, and the extent to which hypothesized "difficulty" (severity) order of items is represented by observed responses. If a researcher has few qualitative data and wants to get preliminary information about the content validity of the instrument, then descriptive assessments using classical test theory should be the first step. As the sample size grows during subsequent stages of instrument development, confidence in the numerical estimates from Rasch and other IRT models (as well as those of classical test theory) would also grow. Classical test theory and IRT can be useful in providing a quantitative assessment of items and scales during the content-validity phase of PRO-measure development. Depending on the particular type of measure and the specific circumstances, the classical test theory and/or the IRT should be considered to help maximize the content validity of PRO measures. Copyright © 2014 Elsevier HS Journals, Inc. All rights reserved.

  9. 26 CFR 301.6222(a)-1 - Consistent treatment of partnership items.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 18 2010-04-01 2010-04-01 false Consistent treatment of partnership items. 301... Consistent treatment of partnership items. (a) In general. The treatment of a partnership item on the partner's return must be consistent with the treatment of that item by the partnership on the partnership...

  10. Problems with the factor analysis of items: Solutions based on item response theory and item parcelling

    Directory of Open Access Journals (Sweden)

    Gideon P. De Bruin

    2004-10-01

    Full Text Available The factor analysis of items often produces spurious results in the sense that unidimensional scales appear multidimensional. This may be ascribed to failure in meeting the assumptions of linearity and normality on which factor analysis is based. Item response theory is explicitly designed for the modelling of the non-linear relations between ordinal variables and provides a strong alternative to the factor analysis of items. Items may also be combined in parcels that are more likely to satisfy the assumptions of factor analysis than do the items. The use of the Rasch rating scale model and the factor analysis of parcels is illustrated with data obtained with the Locus of Control Inventory. The results of these analyses are compared with the results obtained through the factor analysis of items. It is shown that the Rasch rating scale model and the factoring of parcels produce superior results to the factor analysis of items. Recommendations for the analysis of scales are made. Opsomming Die faktorontleding van items lewer dikwels misleidende resultate op, veral in die opsig dat eendimensionele skale as meerdimensioneel voorkom. Hierdie resultate kan dikwels daaraan toegeskryf word dat daar nie aan die aannames van lineariteit en normaliteit waarop faktorontleding berus, voldoen word nie. Itemresponsteorie, wat eksplisiet vir die modellering van die nie-liniêre verbande tussen ordinale items ontwerp is, bied ’n aantreklike alternatief vir die faktorontleding van items. Items kan ook in pakkies gegroepeer word wat meer waarskynlik aan die aannames van faktorontleding voldoen as individuele items. Die gebruik van die Rasch beoordelingskaalmodel en die faktorontleding van pakkies word aan die hand van data wat met die Lokus van Beheervraelys verkry is, gedemonstreer. Die resultate van hierdie ontledings word vergelyk met die resultate wat deur ‘n faktorontleding van die individuele items verkry is. Die resultate dui daarop dat die Rasch

  11. Concept Note General Guidelines - English

    International Development Research Centre (IDRC) Digital Library (Canada)

    NCDP

    Total amount of funding requested in local currency (preferred) or Canadian dollars. • Duraon of ... The following format may be used: Total budget ... maximum length of up to 5 pages (not including the cover page, reference list and annexes).

  12. General Concepts Regarding Risk Appetite

    OpenAIRE

    Ana-Maria Dinu

    2014-01-01

    Risk appetite is a very complex system, therefore one of the most important element of a company’s enterprise risk management (ERM) is the risk appetite defining. A proper risk management means making good choices towards the risks a company faces in order to achieve its objectives and measures to mitigate those risks, not to avoid them. Therefore, the moment risk appetite is understood and clearly defined can become a powerful tool both for managing the occurred risks and business performanc...

  13. Group differences in the heritability of items and test scores

    NARCIS (Netherlands)

    Wicherts, J.M.; Johnson, W.

    2009-01-01

    It is important to understand potential sources of group differences in the heritability of intelligence test scores. On the basis of a basic item response model we argue that heritabilities which are based on dichotomous item scores normally do not generalize from one sample to the next. If groups

  14. 41 CFR 109-1.5109 - Control of sensitive items.

    Science.gov (United States)

    2010-07-01

    ... administrative control of sensitive items assigned for general use within an organizational unit as appropriate... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Control of sensitive...-INTRODUCTION 1.51-Personal Property Management Standards and Practices § 109-1.5109 Control of sensitive items...

  15. A person fit test for IRT models for polytomous items

    NARCIS (Netherlands)

    Glas, Cornelis A.W.; Dagohoy, A.V.

    2007-01-01

    A person fit test based on the Lagrange multiplier test is presented for three item response theory models for polytomous items: the generalized partial credit model, the sequential model, and the graded response model. The test can also be used in the framework of multidimensional ability

  16. ITEM LEVEL DIAGNOSTICS AND MODEL - DATA FIT IN ITEM ...

    African Journals Online (AJOL)

    Global Journal

    Item response theory (IRT) is a framework for modeling and analyzing item response ... data. Though, there is an argument that the evaluation of fit in IRT modeling has been ... National Council on Measurement in Education ... model data fit should be based on three types of ... prediction should be assessed through the.

  17. Item Response Data Analysis Using Stata Item Response Theory Package

    Science.gov (United States)

    Yang, Ji Seung; Zheng, Xiaying

    2018-01-01

    The purpose of this article is to introduce and review the capability and performance of the Stata item response theory (IRT) package that is available from Stata v.14, 2015. Using a simulated data set and a publicly available item response data set extracted from Programme of International Student Assessment, we review the IRT package from…

  18. MIMIC Methods for Assessing Differential Item Functioning in Polytomous Items

    Science.gov (United States)

    Wang, Wen-Chung; Shih, Ching-Lin

    2010-01-01

    Three multiple indicators-multiple causes (MIMIC) methods, namely, the standard MIMIC method (M-ST), the MIMIC method with scale purification (M-SP), and the MIMIC method with a pure anchor (M-PA), were developed to assess differential item functioning (DIF) in polytomous items. In a series of simulations, it appeared that all three methods…

  19. A framework for an inventory model for deteriorating items with expiration under trapezoidal-type demand and partial backlogging

    Directory of Open Access Journals (Sweden)

    Kunal T. Shukla

    2016-09-01

    Full Text Available Background: As in the case of deteriorating items, expiration plays a major role in inventory management, a generalized approach is studied based on an inventory model for deteriorating items with expiration dates. Methods: In this paper, the demand rate during the cycle time is assumed to be trapezoidal. Shortages are allowed and partially backlogged. An inventory replenishment strategy is formulated for trapezoidal demand rates and backlogging rates in general for retailers; with the support of fundamental concepts of calculus. Results: The method is illustrated with the support of numerical examples along with sensitivity analysis with respect to major parameters. Conclusion: This generalized approach provides a platform to develop a strategy using different demand functions and backlogging rates.

  20. Australian Biology Test Item Bank, Years 11 and 12. Volume II: Year 12.

    Science.gov (United States)

    Brown, David W., Ed.; Sewell, Jeffrey J., Ed.

    This document consists of test items which are applicable to biology courses throughout Australia (irrespective of course materials used); assess key concepts within course statement (for both core and optional studies); assess a wide range of cognitive processes; and are relevant to current biological concepts. These items are arranged under…

  1. Australian Biology Test Item Bank, Years 11 and 12. Volume I: Year 11.

    Science.gov (United States)

    Brown, David W., Ed.; Sewell, Jeffrey J., Ed.

    This document consists of test items which are applicable to biology courses throughout Australia (irrespective of course materials used); assess key concepts within course statement (for both core and optional studies); assess a wide range of cognitive processes; and are relevant to current biological concepts. These items are arranged under…

  2. Technology images and concepts of technology in transition. An analysis in the philosophy of technology and general technology; Technikbilder und Technikkonzepte im Wandel. Eine technikphilosophische und allgemeintechnische Analyse

    Energy Technology Data Exchange (ETDEWEB)

    Banse, G. [Forschungszentrum Karlsruhe GmbH Technik und Umwelt (DE). Inst. fuer Technikfolgen-Abschaetzung und Systemanalyse (ITAS); Meier, B. [Potsdam Univ. (Germany). Inst. fuer Arbeitslehre/Technik; Wolffgramm, H. (eds.)

    2002-02-01

    This volume contains contributions resulting from an expert discussion on 'Technology Images and Concepts of Technology in Transition - an analysis in the philosophy of technology and general technology. This expert discussion took place on 6 October 2000 at the State Pedagogical Institute Brandenburg in Ludwigsfelde-Struveshof and was conceived and organized co-operatively by the Forschungszentrum Karlsruhe, Institute for Technology Assessment and Systems Analysis, the University of Potsdam, Institute for the Theory of Work/Technology and Professor Horst Wolffgramm, Frankfurt (Oder). It was the aim of the expert discussion to compile, compare and relate the various positions in the philosophy of technology, general technology science, the history of technology and the didactics of technology of the 'conceptualisation' of technology as a basis for generally understanding technology or for a scientifically based 'image of technology' to each other, and then to make them accessible for curricula within a framework of conceiving general technical education at all school levels. The contributions are grouped according to the two main foci of the event: On the one hand they are concerned with determining a contemporary concept of technology ('Image of technology'). One of the aims is to characterize technological change from the historical-genetic perspective and in this way to access technology as a work of mankind, as an important element of our culture. At the same time it is necessary to forecast future developments or to make future paths of development visible to enable the indication of change by basic innovations. Second, on this basis and supported by educational theory, conclusions are drawn for future-oriented technical general education for all students. The main focus in this is on the linkage between goals, content and subject-specific methods. In order to enable the determination of competence of any individual

  3. A Longitudinal Study of Self Concept From Grade 5 to Grade 9.

    Science.gov (United States)

    Kohr, Richard L.

    This study examined five subscales of the Pennsylvania Educational Quality Assessment self-concept scale, composed largely of items from the Coopersmith Self Esteem Inventory, in terms of socioeconomic status (SES) and sex differences in internal consistency, stability, across time changes in means, and relationship with achievement. In general,…

  4. Item calibration in incomplete testing designs

    Directory of Open Access Journals (Sweden)

    Norman D. Verhelst

    2011-01-01

    Full Text Available This study discusses the justifiability of item parameter estimation in incomplete testing designs in item response theory. Marginal maximum likelihood (MML as well as conditional maximum likelihood (CML procedures are considered in three commonly used incomplete designs: random incomplete, multistage testing and targeted testing designs. Mislevy and Sheenan (1989 have shown that in incomplete designs the justifiability of MML can be deduced from Rubin's (1976 general theory on inference in the presence of missing data. Their results are recapitulated and extended for more situations. In this study it is shown that for CML estimation the justification must be established in an alternative way, by considering the neglected part of the complete likelihood. The problems with incomplete designs are not generally recognized in practical situations. This is due to the stochastic nature of the incomplete designs which is not taken into account in standard computer algorithms. For that reason, incorrect uses of standard MML- and CML-algorithms are discussed.

  5. Editorial Changes and Item Performance: Implications for Calibration and Pretesting

    Directory of Open Access Journals (Sweden)

    Heather Stoffel

    2014-11-01

    Full Text Available Previous research on the impact of text and formatting changes on test-item performance has produced mixed results. This matter is important because it is generally acknowledged that any change to an item requires that it be recalibrated. The present study investigated the effects of seven classes of stylistic changes on item difficulty, discrimination, and response time for a subset of 65 items that make up a standardized test for physician licensure completed by 31,918 examinees in 2012. One of two versions of each item (original or revised was randomly assigned to examinees such that each examinee saw only two experimental items, with each item being administered to approximately 480 examinees. The stylistic changes had little or no effect on item difficulty or discrimination; however, one class of edits -' changing an item from an open lead-in (incomplete statement to a closed lead-in (direct question -' did result in slightly longer response times. Data for nonnative speakers of English were analyzed separately with nearly identical results. These findings have implications for the conventional practice of repretesting (or recalibrating items that have been subjected to minor editorial changes.

  6. Random selection of items. Selection of n1 samples among N items composing a stratum

    International Nuclear Information System (INIS)

    Jaech, J.L.; Lemaire, R.J.

    1987-02-01

    STR-224 provides generalized procedures to determine required sample sizes, for instance in the course of a Physical Inventory Verification at Bulk Handling Facilities. The present report describes procedures to generate random numbers and select groups of items to be verified in a given stratum through each of the measurement methods involved in the verification. (author). 3 refs

  7. Applying automatic item generation to create cohesive physics testlets

    Science.gov (United States)

    Mindyarto, B. N.; Nugroho, S. E.; Linuwih, S.

    2018-03-01

    Computer-based testing has created the demand for large numbers of items. This paper discusses the production of cohesive physics testlets using an automatic item generation concepts and procedures. The testlets were composed by restructuring physics problems to reveal deeper understanding of the underlying physical concepts by inserting a qualitative question and its scientific reasoning question. A template-based testlet generator was used to generate the testlet variants. Using this methodology, 1248 testlet variants were effectively generated from 25 testlet templates. Some issues related to the effective application of the generated physics testlets in practical assessments were discussed.

  8. Selecting Items for Criterion-Referenced Tests.

    Science.gov (United States)

    Mellenbergh, Gideon J.; van der Linden, Wim J.

    1982-01-01

    Three item selection methods for criterion-referenced tests are examined: the classical theory of item difficulty and item-test correlation; the latent trait theory of item characteristic curves; and a decision-theoretic approach for optimal item selection. Item contribution to the standardized expected utility of mastery testing is discussed. (CM)

  9. Assessing item fit for unidimensional item response theory models using residuals from estimated item response functions.

    Science.gov (United States)

    Haberman, Shelby J; Sinharay, Sandip; Chon, Kyong Hee

    2013-07-01

    Residual analysis (e.g. Hambleton & Swaminathan, Item response theory: principles and applications, Kluwer Academic, Boston, 1985; Hambleton, Swaminathan, & Rogers, Fundamentals of item response theory, Sage, Newbury Park, 1991) is a popular method to assess fit of item response theory (IRT) models. We suggest a form of residual analysis that may be applied to assess item fit for unidimensional IRT models. The residual analysis consists of a comparison of the maximum-likelihood estimate of the item characteristic curve with an alternative ratio estimate of the item characteristic curve. The large sample distribution of the residual is proved to be standardized normal when the IRT model fits the data. We compare the performance of our suggested residual to the standardized residual of Hambleton et al. (Fundamentals of item response theory, Sage, Newbury Park, 1991) in a detailed simulation study. We then calculate our suggested residuals using data from an operational test. The residuals appear to be useful in assessing the item fit for unidimensional IRT models.

  10. Brief Sensation Seeking Scale: Latent structure of 8-item and 4-item versions in Peruvian adolescents.

    Science.gov (United States)

    Merino-Soto, Cesar; Salas Blas, Edwin

    2018-01-01

    This research intended to validate two brief scales of sensations seeking with Peruvian adolescents: the eight item scale (BSSS8; Hoyle, Stephenson, Palmgreen, Lorch, y Donohew, 2002) and the four item scale (BSSS4; Stephenson, Hoyle, Slater, y Palmgreen, 2003). Questionnaires were administered to 618 voluntary participants, with an average age of 13.6 years, from different levels of high school, state and private school in a district in the south of Lima. It analyzed the internal structure of both short versions using three models: a) unidimensional (M1), b) oblique or related dimensions (M2), and c) the bifactor model (M3). Results show that both instruments have a single dimension which best represents the variability of the items; a fact that can be explained both by the complexity of the concept and by the small number of items representing each factor, which is more noticeable in the BSSS4. Reliability is within levels found by previous studies: alpha: .745 = BSSS8 and BSSS4 =. 643; omega coefficient: .747 in BSSS8 and .651 in BSSS4. These are considered suitable for the type of instruments studied. Based on the correlation between the two instruments, it was found that there are satisfactory levels of equivalence between the BSSS8 and BSSS4. However, it is recommended that the BSSS4 is mainly used for research and for the purpose of describing populations.

  11. A Concept for the Use and Integration of Super-Conducting Magnets in Structural Systems in General and Maglev Guideway Mega-Structures in Particular

    Science.gov (United States)

    Ussery, Wilfred T.; MacCalla, Eric; MacCalla, Johnetta; Elnimeiri, Mahjoub; Goldsmith, Myron; Polk, Sharon Madison; Jenkins, Mozella; Bragg, Robert H.

    1996-01-01

    Recent breakthroughs in several different fields now make it possible to incorporate the use of superconducting magnets in structures in ways which enhance the performance of structural members or components of structural systems in general and Maglev guideway mega-structures in particular. The building of structural systems which connect appropriately scaled superconducting magnets with the post-tensioned tensile components of beams, girders, or columns would, if coupled with 'state of the art' structure monitoring, feedback and control systems, and advanced computer software, constitute a distinct new generation of structures that would possess the unique characteristic of being heuristic and demand or live-load responsive. The holistic integration of powerful superconducting magnets in structures so that they do actual structural work, creates a class of 'technologically endowed' structures that, in part - literally substitute superconductive electric power and magnetism for concrete and steel. The research and development engineering, and architectural design issues associated with such 'technologically endowed' structural system can now be conceptualized, designed, computer simulates built and tested. The Maglev guideway mega-structure delineated herein incorporates these concepts, and is designed for operation in the median strip of U.S. Interstate Highway 5 from San Diego to Seattle an Vancouver, and possibly on to Fairbanks, Alaska. This system also fits in the median strip of U.S. Interstate Highway 55 and 95 North-South, and 80 and 10, East-West. As a Western Region 'Peace Dividend' project, it could become a National or Bi-National research, design and build, super turnkey project that would create thousands of jobs by applying superconducting, material science, electronic aerospace and other defense industry technologies to a multi-vehicle, multi-use Maglev guideway megastructure that integrates urban mass transit Lower Speed (0-100 mph), High Speed

  12. 48 CFR 852.214-72 - Alternate item(s).

    Science.gov (United States)

    2010-10-01

    ... AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Texts of Provisions and Clauses 852.214-72... 2008) Bids on []* will be given equal consideration along with bids on []** and any such bids received... [].** * Contracting officer will insert an alternate item that is considered acceptable. ** Contracting officer will...

  13. Anteil Stigma-assoziierter Themen im Psychiatrie-Konzept von Medizinstudierenden in der Einführung in die klinische Medizin: Eine Mind-Map Studie [Proportion of stigma-associated items in medical students' psychiatric concepts at the beginning of the clinical phase of medical education: a mind-map study

    Directory of Open Access Journals (Sweden)

    Degirmenci, Ümüt

    2010-02-01

    Full Text Available [english] Aims: Despite many efforts by support groups, mental health professionals and health care policy-makers, a stigmatization of psychiatry as a specialty and of mentally ill people is still prevalent in the general population. Earlier studies have shown that the stigma is prevalent even among psychiatric professionals and students of medicine and psychology. However, past studies on this issue often used questionnaires with a limited validity. Also questionnaires do not necessarily allow a neutral assessment of the underlying concepts of the student. Methods: In this study 133 students were asked to create mind maps on psychiatry. Results: In a systematic evaluation (based on a consensus of psychiatric concepts of 1353 concepts we found non-specific associations (N = 431 and five main categories: (i illness scirpts (n = 487; (ii therapeutic concepts (n = 241, (iii and (iv stigma and forensic psychiatry (81 mentions each; and (v psychopathology (n = 32. Stigma-associated negative concepts were more prevalent than positive connotations. Conclusions: Overall, it was shown that mind maps can be used with ease and quantified according to constructivist learning theory to explore disease concepts without the need for predefined or poorly validated questionnaires.[german] Zielsetzung: Trotz vieler Bemühungen, u. a. von Selbsthilfegruppen, der Fachgesellschaft und der Gesundheitspolitik gibt es in der Allgemeinbevölkerung immer noch eine Stigmatisierung der Psychiatrie als Fachgebiet. Frühere Untersuchungen zeigten, dass auch in der Psychiatrie tätige Menschen und Studierende der Medizin und Psychologie stigmatisierenden Äußerungen zustimmen. Zur genaueren Betrachtung wurden in der Vergangenheit jedoch meist Fragebögen verwendet, die eine begrenzte Validität haben und nicht zwangsläufig eine neutrale Beurteilung der zugrundeliegenden Konzepte der Studierenden erlauben.Methodik: In der vorliegenden Studie wurden 133 Studierende gebeten

  14. A psychometric evaluation of the digital logic concept inventory

    Science.gov (United States)

    Herman, Geoffrey L.; Zilles, Craig; Loui, Michael C.

    2014-10-01

    Concept inventories hold tremendous promise for promoting the rigorous evaluation of teaching methods that might remedy common student misconceptions and promote deep learning. The measurements from concept inventories can be trusted only if the concept inventories are evaluated both by expert feedback and statistical scrutiny (psychometric evaluation). Classical Test Theory and Item Response Theory provide two psychometric frameworks for evaluating the quality of assessment tools. We discuss how these theories can be applied to assessment tools generally and then apply them to the Digital Logic Concept Inventory (DLCI). We demonstrate that the DLCI is sufficiently reliable for research purposes when used in its entirety and as a post-course assessment of students' conceptual understanding of digital logic. The DLCI can also discriminate between students across a wide range of ability levels, providing the most information about weaker students' ability levels.

  15. The general practice of Judo in the formation of self-concept, self-esteem and school performance in children of the first cycle of basic education

    Directory of Open Access Journals (Sweden)

    Marco Alexandre da Silva Batista

    2013-11-01

    As data collection instrument was used Self-Concept Scale Susan Harter validated for the Portuguese population (Martins, Peixoto, Mata, & Monteiro, 1995. Focus groups were developed with Judo coaches and officials education with the intention of evaluating opinions about the practice of Judo and its importance and relationship to the variables studied. The results show that the practice of judo promotes positive developments in the formation of self-concept and self-esteem, also improving school performance.

  16. Meaning and effect of a music concept designed specifically to promote general wellbeing and health for children with cancer receiving music therapy

    OpenAIRE

    Sanfi, Ilan

    2012-01-01

    This text consists of an extract of my master´s thesis (Sanfi, 2007). It discusses a music concept, which is designed to meet bodily and psychosocial needs of children with cancer when receiving chemotherapy. The theory part relates to the development of the special designed music concept, while the empirical part relates to a supplementary pilot study in which a mixed methods design (i.e. semi-structured interviews and questionnaires) is applied. The combination of methods intends to explore...

  17. 41 CFR 101-26.103-2 - Restriction on personal convenience items.

    Science.gov (United States)

    2010-07-01

    ... convenience items. 101-26.103-2 Section 101-26.103-2 Public Contracts and Property Management Federal Property... SOURCES AND PROGRAM 26.1-General § 101-26.103-2 Restriction on personal convenience items. Government... type items intended solely for the personal convenience or to satisfy the personal desire of an...

  18. 26 CFR 301.6231(a)(3)-1 - Partnership items.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 18 2010-04-01 2010-04-01 false Partnership items. 301.6231(a)(3)-1 Section 301... Partnership items. (a) In general. For purposes of subtitle F of the Internal Revenue Code of 1954, the following items which are required to be taken into account for the taxable year of a partnership under...

  19. ABORTION ATTITUDES, 1984-1987-1988 - EFFECTS OF ITEM ORDER AND DIMENSIONALITY

    NARCIS (Netherlands)

    TENVERGERT, E; GILLESPIE, MW; KINGMA, J; KLASEN, H

    The comparability of surveys is often hampered by differences in the item order of presentation. The major focus of the present study was to investigate whether a general item or a specific item at the beginning of the questionnaire would affect the endorsement as well as the scalability of a set of

  20. Item Difficulty in the Evaluation of Computer-Based Instruction: An Example from Neuroanatomy

    Science.gov (United States)

    Chariker, Julia H.; Naaz, Farah; Pani, John R.

    2012-01-01

    This article reports large item effects in a study of computer-based learning of neuroanatomy. Outcome measures of the efficiency of learning, transfer of learning, and generalization of knowledge diverged by a wide margin across test items, with certain sets of items emerging as particularly difficult to master. In addition, the outcomes of…

  1. Detection of Differential Item Functioning with Nonlinear Regression: A Non-IRT Approach Accounting for Guessing

    Science.gov (United States)

    Drabinová, Adéla; Martinková, Patrícia

    2017-01-01

    In this article we present a general approach not relying on item response theory models (non-IRT) to detect differential item functioning (DIF) in dichotomous items with presence of guessing. The proposed nonlinear regression (NLR) procedure for DIF detection is an extension of method based on logistic regression. As a non-IRT approach, NLR can…

  2. 41 CFR 101-30.101-1a - Item of production.

    Science.gov (United States)

    2010-07-01

    ... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true Item of production. 101-30.101-1a Section 101-30.101-1a Public Contracts and Property Management Federal Property Management....1-General § 101-30.101-1a Item of production. Item-of-production means those articles, equipment...

  3. Standardization of the 24-hour diet recall calibration method used in the european prospective investigation into cancer and nutrition (EPIC): general concepts and preliminary results.

    Science.gov (United States)

    Slimani, N; Ferrari, P; Ocké, M; Welch, A; Boeing, H; Liere, M; Pala, V; Amiano, P; Lagiou, A; Mattisson, I; Stripp, C; Engeset, D; Charrondière, R; Buzzard, M; Staveren, W; Riboli, E

    2000-12-01

    Despite increasing interest in the concept of calibration in dietary surveys, there is still little experience in the use and standardization of a common reference dietary method, especially in international studies. In this paper, we present the general theoretical framework and the approaches developed to standardize the computer-assisted 24 h diet recall method (EPIC-SOFT) used to collect about 37 000 24-h dietary recall measurements (24-HDR) from the 10 countries participating in the European Prospective Investigation into Cancer and Nutrition (EPIC). In addition, an analysis of variance was performed to examine the level of standardization of EPIC-SOFT across the 90 interviewers involved in the study. The analysis of variance used a random effects model in which mean energy intake per interviewer was used as the dependent variable, while age, body mass index (BMI), energy requirement, week day, season, special diet, special day, physical activity and the EPIC-SOFT version were used as independent variables. The analysis was performed separately for men and women. The results show no statistical difference between interviewers in all countries for men and five out of eight countries for women, after adjustment for physical activity and the EPIC-SOFT program version used, and the exclusion of one interviewer in Germany (for men), and one in Denmark (for women). These results showed an interviewer effect in certain countries and a significant difference between gender, suggesting an underlying respondent's effect due to the higher under-reporting among women that was consistently observed in EPIC. However, the actual difference between interviewer and country mean energy intakes is about 10%. Furthermore, no statistical differences in mean energy intakes were observed across centres from the same country, except in Italy and Germany for men, and France and Spain for women, where the populations were recruited from areas scattered throughout the countries. Despite

  4. Three Modeling Applications to Promote Automatic Item Generation for Examinations in Dentistry.

    Science.gov (United States)

    Lai, Hollis; Gierl, Mark J; Byrne, B Ellen; Spielman, Andrew I; Waldschmidt, David M

    2016-03-01

    Test items created for dentistry examinations are often individually written by content experts. This approach to item development is expensive because it requires the time and effort of many content experts but yields relatively few items. The aim of this study was to describe and illustrate how items can be generated using a systematic approach. Automatic item generation (AIG) is an alternative method that allows a small number of content experts to produce large numbers of items by integrating their domain expertise with computer technology. This article describes and illustrates how three modeling approaches to item content-item cloning, cognitive modeling, and image-anchored modeling-can be used to generate large numbers of multiple-choice test items for examinations in dentistry. Test items can be generated by combining the expertise of two content specialists with technology supported by AIG. A total of 5,467 new items were created during this study. From substitution of item content, to modeling appropriate responses based upon a cognitive model of correct responses, to generating items linked to specific graphical findings, AIG has the potential for meeting increasing demands for test items. Further, the methods described in this study can be generalized and applied to many other item types. Future research applications for AIG in dental education are discussed.

  5. Modelling sequentially scored item responses

    NARCIS (Netherlands)

    Akkermans, W.

    2000-01-01

    The sequential model can be used to describe the variable resulting from a sequential scoring process. In this paper two more item response models are investigated with respect to their suitability for sequential scoring: the partial credit model and the graded response model. The investigation is

  6. Measuring Social Studies Concept Attainment: Boys and Girls. Report from the Project on A Structure of Concept Attainment Abilities.

    Science.gov (United States)

    Harris, Margaret L.; Tabachnick, B. Robert

    This paper describes test development efforts for measuring achievement of selected concepts in social studies. It includes descriptive item and test statistics for the tests developed. Twelve items were developed for each of 30 concepts. Subject specialists categorized the concepts into three major areas: Geographic Region, Man and Society, and…

  7. Item level diagnostics and model - data fit in item response theory ...

    African Journals Online (AJOL)

    Item response theory (IRT) is a framework for modeling and analyzing item response data. Item-level modeling gives IRT advantages over classical test theory. The fit of an item score pattern to an item response theory (IRT) models is a necessary condition that must be assessed for further use of item and models that best fit ...

  8. General relativity

    International Nuclear Information System (INIS)

    Kenyon, I.R.

    1990-01-01

    General relativity is discussed in this book at a level appropriate to undergraduate students of physics and astronomy. It describes concepts and experimental results, and provides a succinct account of the formalism. A brief review of special relativity is followed by a discussion of the equivalence principle and its implications. Other topics covered include the concepts of curvature and the Schwarzschild metric, test of the general theory, black holes and their properties, gravitational radiation and methods for its detection, the impact of general relativity on cosmology, and the continuing search for a quantum theory of gravity. (author)

  9. Identifying predictors of physics item difficulty: A linear regression approach

    Science.gov (United States)

    Mesic, Vanes; Muratovic, Hasnija

    2011-06-01

    Large-scale assessments of student achievement in physics are often approached with an intention to discriminate students based on the attained level of their physics competencies. Therefore, for purposes of test design, it is important that items display an acceptable discriminatory behavior. To that end, it is recommended to avoid extraordinary difficult and very easy items. Knowing the factors that influence physics item difficulty makes it possible to model the item difficulty even before the first pilot study is conducted. Thus, by identifying predictors of physics item difficulty, we can improve the test-design process. Furthermore, we get additional qualitative feedback regarding the basic aspects of student cognitive achievement in physics that are directly responsible for the obtained, quantitative test results. In this study, we conducted a secondary analysis of data that came from two large-scale assessments of student physics achievement at the end of compulsory education in Bosnia and Herzegovina. Foremost, we explored the concept of “physics competence” and performed a content analysis of 123 physics items that were included within the above-mentioned assessments. Thereafter, an item database was created. Items were described by variables which reflect some basic cognitive aspects of physics competence. For each of the assessments, Rasch item difficulties were calculated in separate analyses. In order to make the item difficulties from different assessments comparable, a virtual test equating procedure had to be implemented. Finally, a regression model of physics item difficulty was created. It has been shown that 61.2% of item difficulty variance can be explained by factors which reflect the automaticity, complexity, and modality of the knowledge structure that is relevant for generating the most probable correct solution, as well as by the divergence of required thinking and interference effects between intuitive and formal physics knowledge

  10. Identifying predictors of physics item difficulty: A linear regression approach

    Directory of Open Access Journals (Sweden)

    Hasnija Muratovic

    2011-06-01

    Full Text Available Large-scale assessments of student achievement in physics are often approached with an intention to discriminate students based on the attained level of their physics competencies. Therefore, for purposes of test design, it is important that items display an acceptable discriminatory behavior. To that end, it is recommended to avoid extraordinary difficult and very easy items. Knowing the factors that influence physics item difficulty makes it possible to model the item difficulty even before the first pilot study is conducted. Thus, by identifying predictors of physics item difficulty, we can improve the test-design process. Furthermore, we get additional qualitative feedback regarding the basic aspects of student cognitive achievement in physics that are directly responsible for the obtained, quantitative test results. In this study, we conducted a secondary analysis of data that came from two large-scale assessments of student physics achievement at the end of compulsory education in Bosnia and Herzegovina. Foremost, we explored the concept of “physics competence” and performed a content analysis of 123 physics items that were included within the above-mentioned assessments. Thereafter, an item database was created. Items were described by variables which reflect some basic cognitive aspects of physics competence. For each of the assessments, Rasch item difficulties were calculated in separate analyses. In order to make the item difficulties from different assessments comparable, a virtual test equating procedure had to be implemented. Finally, a regression model of physics item difficulty was created. It has been shown that 61.2% of item difficulty variance can be explained by factors which reflect the automaticity, complexity, and modality of the knowledge structure that is relevant for generating the most probable correct solution, as well as by the divergence of required thinking and interference effects between intuitive and formal

  11. Psychometric Consequences of Subpopulation Item Parameter Drift

    Science.gov (United States)

    Huggins-Manley, Anne Corinne

    2017-01-01

    This study defines subpopulation item parameter drift (SIPD) as a change in item parameters over time that is dependent on subpopulations of examinees, and hypothesizes that the presence of SIPD in anchor items is associated with bias and/or lack of invariance in three psychometric outcomes. Results show that SIPD in anchor items is associated…

  12. Generalizability theory and item response theory

    NARCIS (Netherlands)

    Glas, Cornelis A.W.; Eggen, T.J.H.M.; Veldkamp, B.P.

    2012-01-01

    Item response theory is usually applied to items with a selected-response format, such as multiple choice items, whereas generalizability theory is usually applied to constructed-response tasks assessed by raters. However, in many situations, raters may use rating scales consisting of items with a

  13. A Method on the Item Investment Risk Interval Decision-making of Processing Ranking Style

    Institute of Scientific and Technical Information of China (English)

    CHEN Li-wen

    2002-01-01

    In this paper, on the bases of the defeot of riskful type and indefinite type decisions, the concept of the type of item investment probability scheduling decision is given, and a linear programming model and its solution are made out. The feasibility of probability scheduling type item investment plan is studied by applying the quality of interval arithmetic.

  14. An empirical comparison of Item Response Theory and Classical Test Theory

    Directory of Open Access Journals (Sweden)

    Špela Progar

    2008-11-01

    Full Text Available Based on nonlinear models between the measured latent variable and the item response, item response theory (IRT enables independent estimation of item and person parameters and local estimation of measurement error. These properties of IRT are also the main theoretical advantages of IRT over classical test theory (CTT. Empirical evidence, however, often failed to discover consistent differences between IRT and CTT parameters and between invariance measures of CTT and IRT parameter estimates. In this empirical study a real data set from the Third International Mathematics and Science Study (TIMSS 1995 was used to address the following questions: (1 How comparable are CTT and IRT based item and person parameters? (2 How invariant are CTT and IRT based item parameters across different participant groups? (3 How invariant are CTT and IRT based item and person parameters across different item sets? The findings indicate that the CTT and the IRT item/person parameters are very comparable, that the CTT and the IRT item parameters show similar invariance property when estimated across different groups of participants, that the IRT person parameters are more invariant across different item sets, and that the CTT item parameters are at least as much invariant in different item sets as the IRT item parameters. The results furthermore demonstrate that, with regards to the invariance property, IRT item/person parameters are in general empirically superior to CTT parameters, but only if the appropriate IRT model is used for modelling the data.

  15. Qualitative Development and Content Validation of the PROMIS Pediatric Sleep Health Items.

    Science.gov (United States)

    Bevans, Katherine B; Meltzer, Lisa J; De La Motte, Anna; Kratchman, Amy; Viél, Dominique; Forrest, Christopher B

    2018-04-25

    To develop the Patient Reported Outcome Measurement Information System (PROMIS) Pediatric Sleep Health item pool and evaluate its content validity. Participants included 8 expert sleep clinician-researchers, 64 children ages 8-17 years, and 54 parents of children ages 5-17 years. We started with item concepts and expressions from the PROMIS Sleep Disturbance and Sleep Related Impairment adult measures. Additional pediatric sleep health concepts were generated by expert (n = 8), child (n = 28), and parent (n = 33) concept elicitation interviews and a systematic review of existing pediatric sleep health questionnaires. Content validity of the item pool was evaluated with item translatability review, readability analysis, and child (n = 36) and parent (n = 21) cognitive interviews. The final pediatric Sleep Health item pool includes 43 items that assess sleep disturbance (children's capacity to fall and stay asleep, sleep quality, dreams, and parasomnias) and sleep-related impairments (daytime sleepiness, low energy, difficulty waking up, and the impact of sleep and sleepiness on cognition, affect, behavior, and daily activities). Items are translatable and relevant and well understood by children ages 8-17 and parents of children ages 5-17. Rigorous qualitative procedures were used to develop and evaluate the content validity of the PROMIS Pediatric Sleep Health item pool. Once the item pool's psychometric properties are established, the scales will be useful for measuring children's subjective experiences of sleep.

  16. Social Comparison and Big-Fish-Little-Pond Effects on Self-Concept and Other Self-Belief Constructs: Role of Generalized and Specific Others

    Science.gov (United States)

    Marsh, Herbert W.; Trautwein, Ulrich; Ludtke, Oliver; Koller, Olaf

    2008-01-01

    Two studies integrate the big-fish-little-pond effect (BFLPE; negative effects of class-average achievement on academic self-concept, ASC), which is based upon educational psychological research, with related social psychological research that is based on social comparison theory. Critical distinctions are the nature of the social comparison…

  17. Application of Item Response Theory to Tests of Substance-related Associative Memory

    Science.gov (United States)

    Shono, Yusuke; Grenard, Jerry L.; Ames, Susan L.; Stacy, Alan W.

    2015-01-01

    A substance-related word association test (WAT) is one of the commonly used indirect tests of substance-related implicit associative memory and has been shown to predict substance use. This study applied an item response theory (IRT) modeling approach to evaluate psychometric properties of the alcohol- and marijuana-related WATs and their items among 775 ethnically diverse at-risk adolescents. After examining the IRT assumptions, item fit, and differential item functioning (DIF) across gender and age groups, the original 18 WAT items were reduced to 14- and 15-items in the alcohol- and marijuana-related WAT, respectively. Thereafter, unidimensional one- and two-parameter logistic models (1PL and 2PL models) were fitted to the revised WAT items. The results demonstrated that both alcohol- and marijuana-related WATs have good psychometric properties. These results were discussed in light of the framework of a unified concept of construct validity (Messick, 1975, 1989, 1995). PMID:25134051

  18. Generalizability theory and item response theory

    OpenAIRE

    Glas, Cornelis A.W.; Eggen, T.J.H.M.; Veldkamp, B.P.

    2012-01-01

    Item response theory is usually applied to items with a selected-response format, such as multiple choice items, whereas generalizability theory is usually applied to constructed-response tasks assessed by raters. However, in many situations, raters may use rating scales consisting of items with a selected-response format. This chapter presents a short overview of how item response theory and generalizability theory were integrated to model such assessments. Further, the precision of the esti...

  19. A note on monotonicity of item response functions for ordered polytomous item response theory models.

    Science.gov (United States)

    Kang, Hyeon-Ah; Su, Ya-Hui; Chang, Hua-Hua

    2018-03-08

    A monotone relationship between a true score (τ) and a latent trait level (θ) has been a key assumption for many psychometric applications. The monotonicity property in dichotomous response models is evident as a result of a transformation via a test characteristic curve. Monotonicity in polytomous models, in contrast, is not immediately obvious because item response functions are determined by a set of response category curves, which are conceivably non-monotonic in θ. The purpose of the present note is to demonstrate strict monotonicity in ordered polytomous item response models. Five models that are widely used in operational assessments are considered for proof: the generalized partial credit model (Muraki, 1992, Applied Psychological Measurement, 16, 159), the nominal model (Bock, 1972, Psychometrika, 37, 29), the partial credit model (Masters, 1982, Psychometrika, 47, 147), the rating scale model (Andrich, 1978, Psychometrika, 43, 561), and the graded response model (Samejima, 1972, A general model for free-response data (Psychometric Monograph no. 18). Psychometric Society, Richmond). The study asserts that the item response functions in these models strictly increase in θ and thus there exists strict monotonicity between τ and θ under certain specified conditions. This conclusion validates the practice of customarily using τ in place of θ in applied settings and provides theoretical grounds for one-to-one transformations between the two scales. © 2018 The British Psychological Society.

  20. 17 CFR 229.10 - (Item 10) General.

    Science.gov (United States)

    2010-04-01

    ... classification system; and a statement informing investors that a security rating is not a recommendation to buy... face of any pro forma financial information required to be disclosed by Article 11 of Regulation S-X... rules, or a system of regulation of a government or governmental authority or self-regulatory...

  1. A Namibian version of the 28 item General Health Questionnaire

    African Journals Online (AJOL)

    Adele

    lence of psychological distress in the country will, by necessity, be piecemeal. Developing region and ... tal illness could be exported from their culture of origin to the de- veloping world.2. The emic .... cross-cultural psychiatry. British Journal of ...

  2. A Generalized Approach to Defining Item Discrimination for DCMs

    Science.gov (United States)

    Henson, Robert; DiBello, Lou; Stout, Bill

    2018-01-01

    Diagnostic classification models (DCMs, also known as cognitive diagnosis models) hold the promise of providing detailed classroom information about the skills a student has or has not mastered. Specifically, DCMs are special cases of constrained latent class models where classes are defined based on mastery/nonmastery of a set of attributes (or…

  3. 17 CFR 229.1100 - (Item 1100) General.

    Science.gov (United States)

    2010-04-01

    ... matters and any pertinent tax matters, exchange controls, currency restrictions or other economic, fiscal... INSTRUCTIONS FOR FILING FORMS UNDER SECURITIES ACT OF 1933, SECURITIES EXCHANGE ACT OF 1934 AND ENERGY POLICY... registration statement or prospectus. 4. If neither the third party nor any of its affiliates has had a direct...

  4. The Ideal Concept of Presidential Threshold Arrangement to Achieve Constitutional Rights of New Political Parties in a simultaneous general election in Indonesia

    OpenAIRE

    Muhammad Mukhtarrija; I gusti Ayu Ketut Rachmi Handayani; Agus Riwanto

    2018-01-01

    This study raises the legal issue against the enactment of Law No. 7 of 2017 on General Elections in Indonesia. The law has violated the constitutional rights of new political parties of the simultaneous general election participants that began in 2017. The injustice is seen in article 222 which requires the provision of presidential threshold for political parties nominating the president and vice-presidential pairs based on the results of general elections in 2014. If this provision is appl...

  5. The Application of Strength of Association Statistics to the Item Analysis of an In-Training Examination in Diagnostic Radiology.

    Science.gov (United States)

    Diamond, James J.; McCormick, Janet

    1986-01-01

    Using item responses from an in-training examination in diagnostic radiology, the application of a strength of association statistic to the general problem of item analysis is illustrated. Criteria for item selection, general issues of reliability, and error of measurement are discussed. (Author/LMO)

  6. Teoria da Resposta ao Item Teoria de la respuesta al item Item response theory

    Directory of Open Access Journals (Sweden)

    Eutalia Aparecida Candido de Araujo

    2009-12-01

    Full Text Available A preocupação com medidas de traços psicológicos é antiga, sendo que muitos estudos e propostas de métodos foram desenvolvidos no sentido de alcançar este objetivo. Entre os trabalhos propostos, destaca-se a Teoria da Resposta ao Item (TRI que, a princípio, veio completar limitações da Teoria Clássica de Medidas, empregada em larga escala até hoje na medida de traços psicológicos. O ponto principal da TRI é que ela leva em consideração o item particularmente, sem relevar os escores totais; portanto, as conclusões não dependem apenas do teste ou questionário, mas de cada item que o compõe. Este artigo propõe-se a apresentar esta Teoria que revolucionou a teoria de medidas.La preocupación con las medidas de los rasgos psicológicos es antigua y muchos estudios y propuestas de métodos fueron desarrollados para lograr este objetivo. Entre estas propuestas de trabajo se incluye la Teoría de la Respuesta al Ítem (TRI que, en principio, vino a completar las limitaciones de la Teoría Clásica de los Tests, ampliamente utilizada hasta hoy en la medida de los rasgos psicológicos. El punto principal de la TRI es que se tiene en cuenta el punto concreto, sin relevar las puntuaciones totales; por lo tanto, los resultados no sólo dependen de la prueba o cuestionario, sino que de cada ítem que lo compone. En este artículo se propone presentar la Teoría que revolucionó la teoría de medidas.The concern with measures of psychological traits is old and many studies and proposals of methods were developed to achieve this goal. Among these proposed methods highlights the Item Response Theory (IRT that, in principle, came to complete limitations of the Classical Test Theory, which is widely used until nowadays in the measurement of psychological traits. The main point of IRT is that it takes into account the item in particular, not relieving the total scores; therefore, the findings do not only depend on the test or questionnaire

  7. The general practice of Judo in the formation of self-concept, self-esteem and school performance in children of the first cycle of basic education

    Directory of Open Access Journals (Sweden)

    Marco Alexandre da Silva Batista

    2013-11-01

    Full Text Available This study aims to relate the practice of Judo with the formation of self-concept, self-esteem and school performance in students from lower primary.The sample has been composed of 531 Portuguese students of which 295 (55.6% are children and 236 (44.4% children, with an average of 9.13 years. From this sample, 394 subjects (74% practiced at least one formal exercise extra-curricular character, and 96 students (24% practiced Judo, with an experience of 9 months to 5 years, and graduations between white belt and green belt.As data collection instrument was used Self-Concept Scale Susan Harter validated for the Portuguese population (Martins, Peixoto, Mata, & Monteiro, 1995. Focus groups were developed with Judo coaches and officials education with the intention of evaluating opinions about the practice of Judo and its importance and relationship to the variables studied. The results show that the practice of judo promotes positive developments in the formation of self-concept and self-esteem, also improving school performance.

  8. Pengendalian Persediaan Primary Items dalam Logistik Konstruksi

    Directory of Open Access Journals (Sweden)

    Lady Lisya

    2016-09-01

    Full Text Available Construction logistics are activities that consist of ordering, storage and transportation of materials of construction projects. Storage material is logistics activity that ensure the availability of materials in project site. Generally, material storage activities have been conducted at the project site. Logistics construction is aimed to support the project activities that the completion schedule has been set. Construction logistics issues is determining the schedule of ordering materials so that the project can be implemented on schedule. The purpose of research is to determine the optimum ordering period for the primary items on the main building structure construction and designing inventory control cards as a mechanism for monitoring procurement of materials. This research has been obtained optimal ordering period for the primary items of main building structure with elements of the work using Fixed Period Requirement method. Inventories were already meet the material requirement of each period. Material management has been conducted based grouping approach as many as 31 groups. In addition, this research has proposed the inventory control cards as an instrument for material procurement monitoring. The implications of inventory control cards are coordinate contracting parties with vendors to plan the replenishment  of materials to meet the work schedule. Further research can be developed with other aspects such as integrated material order system between contractors and vendors to consider the safety stock. In addition, the information system for planning material is an important consideration for construction projects with large scale so that the companies can plan primary items inventory and other materials in the projects completion more easily, quickly and accurately.

  9. Sharing the cost of redundant items

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Moulin, Hervé

    2014-01-01

    We ask how to share the cost of finitely many public goods (items) among users with different needs: some smaller subsets of items are enough to serve the needs of each user, yet the cost of all items must be covered, even if this entails inefficiently paying for redundant items. Typical examples...... are network connectivity problems when an existing (possibly inefficient) network must be maintained. We axiomatize a family cost ratios based on simple liability indices, one for each agent and for each item, measuring the relative worth of this item across agents, and generating cost allocation rules...... additive in costs....

  10. Project Physics Tests 1, Concepts of Motion.

    Science.gov (United States)

    Harvard Univ., Cambridge, MA. Harvard Project Physics.

    Test items relating to Project Physics Unit 1 are presented in this booklet, consisting of 70 multiple-choice and 20 problem-and-essay questions. Concepts of motion are examined with respect to velocities, acceleration, forces, vectors, Newton's laws, and circular motion. Suggestions are made for time consumption in answering some items. Besides…

  11. Instemmingsgeneigdheid en verskillende item- en responsformate in 'n gesommeerde selfbeoordelingskaal

    Directory of Open Access Journals (Sweden)

    Nadene Hanekom

    1998-06-01

    Full Text Available This study examines the degree of acquiescence present when the item and response formats of a summated rating scale are varied. It is often recommended that acquiescence response bias in rating scales may be controlled by using both positively and negatively worded items. Such items are generally worded in the Likert-type format of statements. The purpose of the study was to establish whether items in question format would result in a smaller degree of acquiescence than items worded as statements. the response format was also varied (five- and seven-point options to determine whether this would influence the reliability and degree of acquiescence in the scales. A twenty-item Locus of Control (LC questionnaire was used, but each item was complemented by its opposite, resulting in 40 items. The subjects, divided randomly into two groups, were second year students who had to complete four versions of the questionnaire, plus a shortened version of Bass's scale for measuring acquiescence. The LC version were questions or statements each combined with a five- or seven-point respons format. Partial counterbalancing was introduced by testing on two separate occasions, presenting the tests to the two groups in the opposite order. The degree of acquiescence was assessed by correlating the items with their opposite, and by correlating scores on each version with scores on the acquiescence questionnaire. No major difference were found between the various item and response format in relation to acquiescence. Opsomming Hierdie ondersoek is uitgevoer om te bepaal of die mate van instemmingsgeneigdheid deur die item- en responsformaat van 'n gesommeerde selfbeoordelingskaal beinvloed word. Daar word dikwels aanbeveel dat die gebruik van positief- sowel as negatiefbewoorde items in 'n vraelys instemmingsgeneigdheid beperk. Suike items word gewoonlik in die tradisionele Likertformaat as stellings geformuleer. Die doel van die ondersoek was om te bepaal of items

  12. Improved Approximation Algorithms for Item Pricing with Bounded Degree and Valuation

    Science.gov (United States)

    Hamane, Ryoso; Itoh, Toshiya

    When a store sells items to customers, the store wishes to decide the prices of the items to maximize its profit. If the store sells the items with low (resp. high) prices, the customers buy more (resp. less) items, which provides less profit to the store. It would be hard for the store to decide the prices of items. Assume that a store has a set V of n items and there is a set C of m customers who wish to buy those items. The goal of the store is to decide the price of each item to maximize its profit. We refer to this maximization problem as an item pricing problem. We classify the item pricing problems according to how many items the store can sell or how the customers valuate the items. If the store can sell every item i with unlimited (resp. limited) amount, we refer to this as unlimited supply (resp. limited supply). We say that the item pricing problem is single-minded if each customer j∈C wishes to buy a set ej⊆V of items and assigns valuation w(ej)≥0. For the single-minded item pricing problems (in unlimited supply), Balcan and Blum regarded them as weighted k-hypergraphs and gave several approximation algorithms. In this paper, we focus on the (pseudo) degree of k-hypergraphs and the valuation ratio, i. e., the ratio between the smallest and the largest valuations. Then for the single-minded item pricing problems (in unlimited supply), we show improved approximation algorithms (for k-hypergraphs, general graphs, bipartite graphs, etc.) with respect to the maximum (pseudo) degree and the valuation ratio.

  13. A Bifactor Multidimensional Item Response Theory Model for Differential Item Functioning Analysis on Testlet-Based Items

    Science.gov (United States)

    Fukuhara, Hirotaka; Kamata, Akihito

    2011-01-01

    A differential item functioning (DIF) detection method for testlet-based data was proposed and evaluated in this study. The proposed DIF model is an extension of a bifactor multidimensional item response theory (MIRT) model for testlets. Unlike traditional item response theory (IRT) DIF models, the proposed model takes testlet effects into…

  14. Children's Conceptions of Jesus

    Science.gov (United States)

    Aylward, Karen; Freathy, Rob

    2008-01-01

    This paper presents findings from a recent study investigating young children's (aged 10-11) conceptions of Jesus in England. The overall picture revealed by the study is that whilst there was a general assent amongst pupils in our sample towards an ethical and humanistic conception of the historical Jesus, there was less of a consensus about…

  15. Emergency Power For Critical Items

    Science.gov (United States)

    Young, William R.

    2009-07-01

    Natural disasters, such as hurricanes, floods, tornados, and tsunami, are becoming a greater problem as climate change impacts our environment. Disasters, whether natural or man made, destroy lives, homes, businesses and the natural environment. Such disasters can happen with little or no warning, leaving hundreds or even thousands of people without medical services, potable water, sanitation, communications and electrical services for up to several weeks. In our modern world, the need for electricity has become a necessity. Modern building codes and new disaster resistant building practices are reducing the damage to homes and businesses. Emergency gasoline and diesel generators are becoming common place for power outages. Generators need fuel, which may not be available after a disaster, but Photovoltaic (solar-electric) systems supply electricity without petroleum fuel as they are powered by the sun. Photovoltaic (PV) systems can provide electrical power for a home or business. PV systems can operate as utility interactive or stand-alone with battery backup. Determining your critical load items and sizing the photovoltaic system for those critical items, guarantees their operation in a disaster.

  16. PENGEMBANGAN TES BERPIKIR KRITIS DENGAN PENDEKATAN ITEM RESPONSE THEORY

    Directory of Open Access Journals (Sweden)

    Fajrianthi Fajrianthi

    2016-06-01

    Full Text Available Penelitian ini bertujuan untuk menghasilkan sebuah alat ukur (tes berpikir kritis yang valid dan reliabel untuk digunakan, baik dalam lingkup pendidikan maupun kerja di Indonesia. Tahapan penelitian dilakukan berdasarkan tahap pengembangan tes menurut Hambleton dan Jones (1993. Kisi-kisi dan pembuatan butir didasarkan pada konsep dalam tes Watson-Glaser Critical Thinking Appraisal (WGCTA. Pada WGCTA, berpikir kritis terdiri dari lima dimensi yaitu Inference, Recognition Assumption, Deduction, Interpretation dan Evaluation of arguments. Uji coba tes dilakukan pada 1.453 peserta tes seleksi karyawan di Surabaya, Gresik, Tuban, Bojonegoro, Rembang. Data dikotomi dianalisis dengan menggunakan model IRT dengan dua parameter yaitu daya beda dan tingkat kesulitan butir. Analisis dilakukan dengan menggunakan program statistik Mplus versi 6.11 Sebelum melakukan analisis dengan IRT, dilakukan pengujian asumsi yaitu uji unidimensionalitas, independensi lokal dan Item Characteristic Curve (ICC. Hasil analisis terhadap 68 butir menghasilkan 15 butir dengan daya beda yang cukup baik dan tingkat kesulitan butir yang berkisar antara –4 sampai dengan 2.448. Sedikitnya jumlah butir yang berkualitas baik disebabkan oleh kelemahan dalam menentukan subject matter experts di bidang berpikir kritis dan pemilihan metode skoring. Kata kunci: Pengembangan tes, berpikir kritis, item response theory   DEVELOPING CRITICAL THINKING TEST UTILISING ITEM RESPONSE THEORY Abstract The present study was aimed to develop a valid and reliable instrument in assesing critical thinking which can be implemented both in educational and work settings in Indonesia. Following the Hambleton and Jones’s (1993 procedures on test development, the study developed the instrument by employing the concept of critical thinking from Watson-Glaser Critical Thinking Appraisal (WGCTA. The study included five dimensions of critical thinking as adopted from the WGCTA: Inference, Recognition

  17. Learning abstract visual concepts via probabilistic program induction in a Language of Thought.

    Science.gov (United States)

    Overlan, Matthew C; Jacobs, Robert A; Piantadosi, Steven T

    2017-11-01

    The ability to learn abstract concepts is a powerful component of human cognition. It has been argued that variable binding is the key element enabling this ability, but the computational aspects of variable binding remain poorly understood. Here, we address this shortcoming by formalizing the Hierarchical Language of Thought (HLOT) model of rule learning. Given a set of data items, the model uses Bayesian inference to infer a probability distribution over stochastic programs that implement variable binding. Because the model makes use of symbolic variables as well as Bayesian inference and programs with stochastic primitives, it combines many of the advantages of both symbolic and statistical approaches to cognitive modeling. To evaluate the model, we conducted an experiment in which human subjects viewed training items and then judged which test items belong to the same concept as the training items. We found that the HLOT model provides a close match to human generalization patterns, significantly outperforming two variants of the Generalized Context Model, one variant based on string similarity and the other based on visual similarity using features from a deep convolutional neural network. Additional results suggest that variable binding happens automatically, implying that binding operations do not add complexity to peoples' hypothesized rules. Overall, this work demonstrates that a cognitive model combining symbolic variables with Bayesian inference and stochastic program primitives provides a new perspective for understanding people's patterns of generalization. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Evaluating construct validity of the second version of the Copenhagen Psychosocial Questionnaire through analysis of differential item functioning and differential item effect

    DEFF Research Database (Denmark)

    Bjorner, Jakob Bue; Pejtersen, Jan Hyld

    2010-01-01

    AIMS: To evaluate the construct validity of the Copenhagen Psychosocial Questionnaire II (COPSOQ II) by means of tests for differential item functioning (DIF) and differential item effect (DIE). METHODS: We used a Danish general population postal survey (n = 4,732 with 3,517 wage earners) with a ...

  19. Multilevel Higher-Order Item Response Theory Models

    Science.gov (United States)

    Huang, Hung-Yu; Wang, Wen-Chung

    2014-01-01

    In the social sciences, latent traits often have a hierarchical structure, and data can be sampled from multiple levels. Both hierarchical latent traits and multilevel data can occur simultaneously. In this study, we developed a general class of item response theory models to accommodate both hierarchical latent traits and multilevel data. The…

  20. 17 CFR 229.909 - (Item 909) Conflicts of interest.

    Science.gov (United States)

    2010-04-01

    ...) Conflicts of interest. (a) Briefly describe the general partner's fiduciary duties to each partnership subject to the roll-up transaction and each actual or potential material conflict of interest between the... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false (Item 909) Conflicts of...

  1. 26 CFR 1.461-5 - Recurring item exception.

    Science.gov (United States)

    2010-04-01

    ... general. Except as otherwise provided in paragraph (c) of this section, a taxpayer using an accrual method... method of accounting for one or more types of recurring items incurred by the taxpayer. In the case of... basis in the future. (4) Materiality requirement. For purposes of this paragraph (b): (i) In determining...

  2. A Balance Sheet for Educational Item Banking.

    Science.gov (United States)

    Hiscox, Michael D.

    Educational item banking presents observers with a considerable paradox. The development of test items from scratch is viewed as wasteful, a luxury in times of declining resources. On the other hand, item banking has failed to become a mature technology despite large amounts of money and the efforts of talented professionals. The question of which…

  3. 76 FR 60474 - Commercial Item Handbook

    Science.gov (United States)

    2011-09-29

    ... DEPARTMENT OF DEFENSE Defense Acquisition Regulations System Commercial Item Handbook AGENCY.... SUMMARY: DoD has updated its Commercial Item Handbook. The purpose of the Handbook is to help acquisition personnel develop sound business strategies for procuring commercial items. DoD is seeking industry input on...

  4. Towards an authoring system for item construction

    NARCIS (Netherlands)

    Rikers, Jos H.A.N.

    1988-01-01

    The process of writing test items is analyzed, and a blueprint is presented for an authoring system for test item writing to reduce invalidity and to structure the process of item writing. The developmental methodology is introduced, and the first steps in the process are reported. A historical

  5. Obtaining a Proportional Allocation by Deleting Items

    NARCIS (Netherlands)

    Dorn, B.; de Haan, R.; Schlotter, I.; Röthe, J.

    2017-01-01

    We consider the following control problem on fair allocation of indivisible goods. Given a set I of items and a set of agents, each having strict linear preference over the items, we ask for a minimum subset of the items whose deletion guarantees the existence of a proportional allocation in the

  6. Item Analysis in Introductory Economics Testing.

    Science.gov (United States)

    Tinari, Frank D.

    1979-01-01

    Computerized analysis of multiple choice test items is explained. Examples of item analysis applications in the introductory economics course are discussed with respect to three objectives: to evaluate learning; to improve test items; and to help improve classroom instruction. Problems, costs and benefits of the procedures are identified. (JMD)

  7. Effect of Peer-Led Team Learning (PLTL) on Student Achievement, Attitude, and Self-Concept in College General Chemistry in Randomized and Quasi Experimental Designs

    Science.gov (United States)

    Chan, Julia Y. K.; Bauer, Christopher F.

    2015-01-01

    This study investigated exam achievement and affective characteristics of students in general chemistry in a fully-randomized experimental design, contrasting Peer-Led Team Learning (PLTL) participation with a control group balanced for time-on-task and study activity. This study population included two independent first-semester courses with…

  8. Clusters of cultures: diversity in meaning of family value and gender role items across Europe.

    Science.gov (United States)

    van Vlimmeren, Eva; Moors, Guy B D; Gelissen, John P T M

    2017-01-01

    Survey data are often used to map cultural diversity by aggregating scores of attitude and value items across countries. However, this procedure only makes sense if the same concept is measured in all countries. In this study we argue that when (co)variances among sets of items are similar across countries, these countries share a common way of assigning meaning to the items. Clusters of cultures can then be observed by doing a cluster analysis on the (co)variance matrices of sets of related items. This study focuses on family values and gender role attitudes. We find four clusters of cultures that assign a distinct meaning to these items, especially in the case of gender roles. Some of these differences reflect response style behavior in the form of acquiescence. Adjusting for this style effect impacts on country comparisons hence demonstrating the usefulness of investigating the patterns of meaning given to sets of items prior to aggregating scores into cultural characteristics.

  9. Uranium ISR Mine Closure — General Concepts and Model-Based Simulation of Natural Attenuation for South-Australian Mine Sites

    Energy Technology Data Exchange (ETDEWEB)

    Jeuken, B.; Märten, H.; Woods, P., E-mail: horst.maerten@heathgate.com.au [Heathgate Resources Pty. Ltd. (Heathgate), Adelaide (Australia); Kalka, H.; Nicolai, J. [Umwelt- und Ingenieurtechnik GmbH Dresden (UIT), Dresden (Germany)

    2014-05-15

    Heathgate has demonstrated the effect of natural attenuation (NA) in post in-situ recovery (ISR) aquifer regions during the operation of the Beverley mine since 2001. Enhanced natural attenuation (ENA) has been considered as the key component of the mine closure concept for the new Beverley Four Mile (BFM) project, complemented by an extensive monitoring program. Data from batch and column tests for BFM core samples was used to calibrate a reactive transport model, whose application in conjunction with the hydrological modelling of the BFM aquifer has shown that NA will result in the restoration of the aquifer in time. ENA within a staged mine development program under the site-specific circumstances is discussed. (author)

  10. ITEM-QM solutions for EM problems in image reconstruction exemplary for the Compton Camera

    CERN Document Server

    Pauli, Josef; Anton, G

    2002-01-01

    Imaginary time expectation maximation (ITEM), a new algorithm for expectation maximization problems based on the quantum mechanics energy minimalization via imaginary (euclidian) time evolution is presented. Both (the algorithm as well as the implementation (http://www.johannes-pauli.de/item/index.html) are published under the terms of General GNU public License (http://www.gnu.org/copyleft/gpl.html). Due to its generality ITEM is applicable to various image reconstruction problems like CT, PET, SPECT, NMR, Compton Camera, tomosynthesis as well as any other energy minimization problem. The choice of the optimal ITEM Hamiltonian is discussed and numerical results are presented for the Compton Camera.

  11. Concepts of formal concept analysis

    Science.gov (United States)

    Žáček, Martin; Homola, Dan; Miarka, Rostislav

    2017-07-01

    The aim of this article is apply of Formal Concept Analysis on concept of world. Formal concept analysis (FCA) as a methodology of data analysis, information management and knowledge representation has potential to be applied to a verity of linguistic problems. FCA is mathematical theory for concepts and concept hierarchies that reflects an understanding of concept. Formal concept analysis explicitly formalizes extension and intension of a concept, their mutual relationships. A distinguishing feature of FCA is an inherent integration of three components of conceptual processing of data and knowledge, namely, the discovery and reasoning with concepts in data, discovery and reasoning with dependencies in data, and visualization of data, concepts, and dependencies with folding/unfolding capabilities.

  12. New technologies for item monitoring

    International Nuclear Information System (INIS)

    Abbott, J.A.; Waddoups, I.G.

    1993-12-01

    This report responds to the Department of Energy's request that Sandia National Laboratories compare existing technologies against several advanced technologies as they apply to DOE needs to monitor the movement of material, weapons, or personnel for safety and security programs. The authors describe several material control systems, discuss their technologies, suggest possible applications, discuss assets and limitations, and project costs for each system. The following systems are described: WATCH system (Wireless Alarm Transmission of Container Handling); Tag system (an electrostatic proximity sensor); PANTRAK system (Personnel And Material Tracking); VRIS (Vault Remote Inventory System); VSIS (Vault Safety and Inventory System); AIMS (Authenticated Item Monitoring System); EIVS (Experimental Inventory Verification System); Metrox system (canister monitoring system); TCATS (Target Cueing And Tracking System); LGVSS (Light Grid Vault Surveillance System); CSS (Container Safeguards System); SAMMS (Security Alarm and Material Monitoring System); FOIDS (Fiber Optic Intelligence ampersand Detection System); GRADS (Graded Radiation Detection System); and PINPAL (Physical Inventory Pallet)

  13. New technologies for item monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Abbott, J.A. [EG & G Energy Measurements, Albuquerque, NM (United States); Waddoups, I.G. [Sandia National Labs., Albuquerque, NM (United States)

    1993-12-01

    This report responds to the Department of Energy`s request that Sandia National Laboratories compare existing technologies against several advanced technologies as they apply to DOE needs to monitor the movement of material, weapons, or personnel for safety and security programs. The authors describe several material control systems, discuss their technologies, suggest possible applications, discuss assets and limitations, and project costs for each system. The following systems are described: WATCH system (Wireless Alarm Transmission of Container Handling); Tag system (an electrostatic proximity sensor); PANTRAK system (Personnel And Material Tracking); VRIS (Vault Remote Inventory System); VSIS (Vault Safety and Inventory System); AIMS (Authenticated Item Monitoring System); EIVS (Experimental Inventory Verification System); Metrox system (canister monitoring system); TCATS (Target Cueing And Tracking System); LGVSS (Light Grid Vault Surveillance System); CSS (Container Safeguards System); SAMMS (Security Alarm and Material Monitoring System); FOIDS (Fiber Optic Intelligence & Detection System); GRADS (Graded Radiation Detection System); and PINPAL (Physical Inventory Pallet).

  14. KALIMER design concept report

    Energy Technology Data Exchange (ETDEWEB)

    Park, Chang Kyu; Kim, Young Cheol; Kim, Young In; Kim, Young Gyun; Kim, Eui Kwang; Song, Hoon; Chung, Hyun Tai; Hwang, Woan; Nam, Cheol; Sub, Sim Yoon; Kim, Yeon Sik; Whan, Wim Myung; Min, Byung Tae; Yoo, Bong; Lee, Jae Han; Lee, Hyeong Yeon; Kim, Jong Bum; Koo, Gyeong Hoi; Ham, Chang Shik; Kwon, Kee Choon; Kim, Jung Taek; Park, Jae Chang; Lee, Jung Woon; Lee, Yong Hee; Kim, Chang Hwoi; Sim, Bong Shick; Hahn, Do Hee; Choi, Jong Hyeun; Kwon, Sang Woon

    1997-07-01

    KAERI is working for the development of KALIMER and work is being done for methodology development, experimental facility set up and design concept development. The development target of KALIMER has been set as to make KALIMER safer, more economic, more resistant to nuclear proliferation, and yield less impact on the environment. To achieve the target, study has been made for setting up the design concept of KALIMER including the assessment of various possible design alternatives. This report is the results of the study for the KALIMER concept study and describes the design concept of KALIMER. The developed design concept study and describes the design concept of KALIMER. The developed design concept is to be used as the starting point of the next development phase of conceptual design and the concept will be refined and modified in the conceptual design phase. The scope of the work has been set as the NSSS and essential BOP systems. For systems, NSSS and functionally related major BOP are covered. Sizing and specifying conceptual structure are covered for major equipment. Equipment and piping are arranged for the parts where the arrangement is critical in fulfilling the foresaid intention of setting up the KALIMER design concept. This report consists of 10 chapters. Chapter 2 is for the top level design requirements of KALIMER and it serves as the basis of KALIMER design concept development. Chapter 3 summarizes the KALIMER concept and describes the general design features. The remaining chapters are for specific systems. (author). 29 tabs., 37 figs.

  15. KALIMER design concept report

    International Nuclear Information System (INIS)

    Park, Chang Kyu; Kim, Young Cheol; Kim, Young In; Kim, Young Gyun; Kim, Eui Kwang; Song, Hoon; Chung, Hyun Tai; Hwang, Woan; Nam, Cheol; Sim Yoon Sub; Kim, Yeon Sik; Wim Myung Whan; Min, Byung Tae; Yoo, Bong; Lee, Jae Han; Lee, Hyeong Yeon; Kim, Jong Bum; Koo, Gyeong Hoi; Ham, Chang Shik; Kwon, Kee Choon; Kim, Jung Taek; Park, Jae Chang; Lee, Jung Woon; Lee, Yong Hee; Kim, Chang Hwoi; Sim, Bong Shick; Hahn, Do Hee; Choi, Jong Hyeun; Kwon, Sang Woon.

    1997-07-01

    KAERI is working for the development of KALIMER and work is being done for methodology development, experimental facility set up and design concept development. The development target of KALIMER has been set as to make KALIMER safer, more economic, more resistant to nuclear proliferation, and yield less impact on the environment. To achieve the target, study has been made for setting up the design concept of KALIMER including the assessment of various possible design alternatives. This report is the results of the study for the KALIMER concept study and describes the design concept of KALIMER. The developed design concept study and describes the design concept of KALIMER. The developed design concept is to be used as the starting point of the next development phase of conceptual design and the concept will be refined and modified in the conceptual design phase. The scope of the work has been set as the NSSS and essential BOP systems. For systems, NSSS and functionally related major BOP are covered. Sizing and specifying conceptual structure are covered for major equipment. Equipment and piping are arranged for the parts where the arrangement is critical in fulfilling the foresaid intention of setting up the KALIMER design concept. This report consists of 10 chapters. Chapter 2 is for the top level design requirements of KALIMER and it serves as the basis of KALIMER design concept development. Chapter 3 summarizes the KALIMER concept and describes the general design features. The remaining chapters are for specific systems. (author). 29 tabs., 37 figs

  16. Approximation Preserving Reductions among Item Pricing Problems

    Science.gov (United States)

    Hamane, Ryoso; Itoh, Toshiya; Tomita, Kouhei

    When a store sells items to customers, the store wishes to determine the prices of the items to maximize its profit. Intuitively, if the store sells the items with low (resp. high) prices, the customers buy more (resp. less) items, which provides less profit to the store. So it would be hard for the store to decide the prices of items. Assume that the store has a set V of n items and there is a set E of m customers who wish to buy those items, and also assume that each item i ∈ V has the production cost di and each customer ej ∈ E has the valuation vj on the bundle ej ⊆ V of items. When the store sells an item i ∈ V at the price ri, the profit for the item i is pi = ri - di. The goal of the store is to decide the price of each item to maximize its total profit. We refer to this maximization problem as the item pricing problem. In most of the previous works, the item pricing problem was considered under the assumption that pi ≥ 0 for each i ∈ V, however, Balcan, et al. [In Proc. of WINE, LNCS 4858, 2007] introduced the notion of “loss-leader, ” and showed that the seller can get more total profit in the case that pi < 0 is allowed than in the case that pi < 0 is not allowed. In this paper, we derive approximation preserving reductions among several item pricing problems and show that all of them have algorithms with good approximation ratio.

  17. On random age and remaining lifetime for populations of items

    DEFF Research Database (Denmark)

    Finkelstein, M.; Vaupel, J.

    2015-01-01

    We consider items that are incepted into operation having already a random (initial) age and define the corresponding remaining lifetime. We show that these lifetimes are identically distributed when the age distribution is equal to the equilibrium distribution of the renewal theory. Then we...... develop the population studies approach to the problem and generalize the setting in terms of stationary and stable populations of items. We obtain new stochastic comparisons for the corresponding population ages and remaining lifetimes that can be useful in applications. Copyright (c) 2014 John Wiley...

  18. Losing Items in the Psychogeriatric Nursing Home

    Directory of Open Access Journals (Sweden)

    J. van Hoof PhD

    2016-09-01

    Full Text Available Introduction: Losing items is a time-consuming occurrence in nursing homes that is ill described. An explorative study was conducted to investigate which items got lost by nursing home residents, and how this affects the residents and family caregivers. Method: Semi-structured interviews and card sorting tasks were conducted with 12 residents with early-stage dementia and 12 family caregivers. Thematic analysis was applied to the outcomes of the sessions. Results: The participants stated that numerous personal items and assistive devices get lost in the nursing home environment, which had various emotional, practical, and financial implications. Significant amounts of time are spent on trying to find items, varying from 1 hr up to a couple of weeks. Numerous potential solutions were identified by the interviewees. Discussion: Losing items often goes together with limitations to the participation of residents. Many family caregivers are reluctant to replace lost items, as these items may get lost again.

  19. A Generalized Version of a Low Velocity Impact between a Rigid Sphere and a Transversely Isotropic Strain-Hardening Plate Supported by a Rigid Substrate Using the Concept of Noninteger Derivatives

    Directory of Open Access Journals (Sweden)

    Abdon Atangana

    2013-01-01

    Full Text Available A low velocity impact between a rigid sphere and transversely isotropic strain-hardening plate supported by a rigid substrate is generalized to the concept of noninteger derivatives order. A brief history of fractional derivatives order is presented. The fractional derivatives order adopted is in Caputo sense. The new equation is solved via the analytical technique, the Homotopy decomposition method (HDM. The technique is described and the numerical simulations are presented. Since it is very important to accurately predict the contact force and its time history, the three stages of the indentation process, including (1 the elastic indentation, (2 the plastic indentation, and (3 the elastic unloading stages, are investigated.

  20. Instructional Topics in Educational Measurement (ITEMS) Module: Using Automated Processes to Generate Test Items

    Science.gov (United States)

    Gierl, Mark J.; Lai, Hollis

    2013-01-01

    Changes to the design and development of our educational assessments are resulting in the unprecedented demand for a large and continuous supply of content-specific test items. One way to address this growing demand is with automatic item generation (AIG). AIG is the process of using item models to generate test items with the aid of computer…

  1. Sexual Orientation Self-Concept Ambiguity: Scale Adaptation and Validation.

    Science.gov (United States)

    Talley, Amelia E; Stevens, Jordan E

    2017-07-01

    The current article describes the adaptation of a measure of sexual orientation self-concept ambiguity (SSA) from an existing measure of general self-concept clarity. Latent "trait" scores of SSA reflect the extent to which a person's beliefs about their own sexual orientation are perceived as inconsistent, unreliable, or incongruent. Sexual minority and heterosexual women ( n = 348), ages 18 to 30, completed a cross-sectional survey. Categorical confirmatory factor analysis guided the selection of items to form a 10-item, self-report measure of SSA. In the current report, we also examine (a) reliability of the 10-item scale score, (b) measurement invariance based on respondents' sexual identity status and age group, and (c) correlations with preexisting surveys that purport to measure similar constructs and theoretical correlates. Evidence for internal reliability, measurement invariance (based on respondent sex), and convergent validity was also investigated in an independent, validation sample. The lowest SSA scores were reported by women who self-ascribed an exclusively heterosexual or exclusively lesbian/gay sexual identity, whereas those who reported a bisexual, mostly lesbian/gay, or mostly heterosexual identity, reported relatively higher SSA scores.

  2. An EPQ model with imperfect items using interval grey numbers

    Directory of Open Access Journals (Sweden)

    Erdal Aydemir

    2015-01-01

    Full Text Available The classic economic production quantity (EPQ model has been widely used to determine the optimal production quantity. However, the analysis for finding an EPQ model has many weaknesses which lead many researchers and practitioners to make extensions in several aspects on the original EPQ model. The basic assumption of EPQ model is that 100% of manufactured products are non-defective that is not valid for many production processes generally. The purpose of this paper is to develop an EPQ model with grey demand rate and cost values with maximum backorder level allowed with the good quality items in units under an imperfect production process. The imperfect items are considered to be low quality items which are sold to a particular purchaser at a lower price and, the others are reworked and scrapped. A mathematical model is developed and then an industrial example is presented on the wooden chipboard production process for illustration of the proposed model.

  3. An Effective Multimedia Item Shell Design for Individualized Education: The Crome Project

    Directory of Open Access Journals (Sweden)

    Irene Cheng

    2008-01-01

    Full Text Available There are several advantages to creating multimedia item types and applying computer-based adaptive testing in education. First is the capability to motivate learning by making the learners feel more engaged and in an interactive environment. Second is a better concept representation, which is not possible in conventional multiple-choice tests. Third is the advantage of individualized curriculum design, rather than a curriculum designed for an average student. Fourth is a good choice of the next question, associated with the appropriate difficulty level based on a student's response to the current question. However, many issues need to be addressed when achieving these goals, including: (a the large number of item types required to represent the current multiple-choice questions in multimedia formats, (b the criterion used to determine the difficulty level of a multimedia question item, and (c the methodology applied to the question selection process for individual students. In this paper, we propose a multimedia item shell design that not only reduces the number of item types required, but also computes difficulty level of an item automatically. The concept of question seed is introduced to make content creation more cost-effective. The proposed item shell framework facilitates efficient communication between user responses at the client, and the scoring agents integrated with a student ability assessor at the server. We also describe approaches for automatically estimating difficulty level of questions, and discuss preliminary evaluation of multimedia item types by students.

  4. Students' proficiency scores within multitrait item response theory

    Science.gov (United States)

    Scott, Terry F.; Schumayer, Daniel

    2015-12-01

    In this paper we present a series of item response models of data collected using the Force Concept Inventory. The Force Concept Inventory (FCI) was designed to poll the Newtonian conception of force viewed as a multidimensional concept, that is, as a complex of distinguishable conceptual dimensions. Several previous studies have developed single-trait item response models of FCI data; however, we feel that multidimensional models are also appropriate given the explicitly multidimensional design of the inventory. The models employed in the research reported here vary in both the number of fitting parameters and the number of underlying latent traits assumed. We calculate several model information statistics to ensure adequate model fit and to determine which of the models provides the optimal balance of information and parsimony. Our analysis indicates that all item response models tested, from the single-trait Rasch model through to a model with ten latent traits, satisfy the standard requirements of fit. However, analysis of model information criteria indicates that the five-trait model is optimal. We note that an earlier factor analysis of the same FCI data also led to a five-factor model. Furthermore the factors in our previous study and the traits identified in the current work match each other well. The optimal five-trait model assigns proficiency scores to all respondents for each of the five traits. We construct a correlation matrix between the proficiencies in each of these traits. This correlation matrix shows strong correlations between some proficiencies, and strong anticorrelations between others. We present an interpretation of this correlation matrix.

  5. Validity and Reliability of the 8-Item Work Limitations Questionnaire.

    Science.gov (United States)

    Walker, Timothy J; Tullar, Jessica M; Diamond, Pamela M; Kohl, Harold W; Amick, Benjamin C

    2017-12-01

    Purpose To evaluate factorial validity, scale reliability, test-retest reliability, convergent validity, and discriminant validity of the 8-item Work Limitations Questionnaire (WLQ) among employees from a public university system. Methods A secondary analysis using de-identified data from employees who completed an annual Health Assessment between the years 2009-2015 tested research aims. Confirmatory factor analysis (CFA) (n = 10,165) tested the latent structure of the 8-item WLQ. Scale reliability was determined using a CFA-based approach while test-retest reliability was determined using the intraclass correlation coefficient. Convergent/discriminant validity was tested by evaluating relations between the 8-item WLQ with health/performance variables for convergent validity (health-related work performance, number of chronic conditions, and general health) and demographic variables for discriminant validity (gender and institution type). Results A 1-factor model with three correlated residuals demonstrated excellent model fit (CFI = 0.99, TLI = 0.99, RMSEA = 0.03, and SRMR = 0.01). The scale reliability was acceptable (0.69, 95% CI 0.68-0.70) and the test-retest reliability was very good (ICC = 0.78). Low-to-moderate associations were observed between the 8-item WLQ and the health/performance variables while weak associations were observed between the demographic variables. Conclusions The 8-item WLQ demonstrated sufficient reliability and validity among employees from a public university system. Results suggest the 8-item WLQ is a usable alternative for studies when the more comprehensive 25-item WLQ is not available.

  6. Calibration of the PROMIS physical function item bank in Dutch patients with rheumatoid arthritis.

    Directory of Open Access Journals (Sweden)

    Martijn A H Oude Voshaar

    Full Text Available OBJECTIVE: To calibrate the Dutch-Flemish version of the PROMIS physical function (PF item bank in patients with rheumatoid arthritis (RA and to evaluate cross-cultural measurement equivalence with US general population and RA data. METHODS: Data were collected from RA patients enrolled in the Dutch DREAM registry. An incomplete longitudinal anchored design was used where patients completed all 121 items of the item bank over the course of three waves of data collection. Item responses were fit to a generalized partial credit model adapted for longitudinal data and the item parameters were examined for differential item functioning (DIF across country, age, and sex. RESULTS: In total, 690 patients participated in the study at time point 1 (T2, N = 489; T3, N = 311. The item bank could be successfully fitted to a generalized partial credit model, with the number of misfitting items falling within acceptable limits. Seven items demonstrated DIF for sex, while 5 items showed DIF for age in the Dutch RA sample. Twenty-five (20% items were flagged for cross-cultural DIF compared to the US general population. However, the impact of observed DIF on total physical function estimates was negligible. DISCUSSION: The results of this study showed that the PROMIS PF item bank adequately fit a unidimensional IRT model which provides support for applications that require invariant estimates of physical function, such as computer adaptive testing and targeted short forms. More studies are needed to further investigate the cross-cultural applicability of the US-based PROMIS calibration and standardized metric.

  7. Ancient Item Spoilage Ritual Used in Nomadic Burial Rite

    Directory of Open Access Journals (Sweden)

    Beisenov Arman Z.

    2017-07-01

    Full Text Available The article considers the findings of items in ancient burials which were intentionally spoiled prior to deposition in graves. This tradition was widely spread both in terms of chronology and geography, and therefore cannot be attributed to any individual cultures or regions. The authors present new information on the ritual obtained during an investigation of Borsyk burial mound of the Middle Sarmatian period located in West Kazakhstan. The central grave of barrow 6 contained a heavily damaged bronze cauldron. The grave was looted in antiquity. Individual scattered bones of a human skeleton and minor gold foil adornments from the ceremonial dress of a nobleman were discovered in the grave. The authors suggest that the cauldron was intentionally deformed by the participants of an ancient mortuary and memorial ritual. According to the principal hypothesis concerning the essence of this ritual, spoilage of the items was related to the idea of assign the items with “different” and “transcendent” properties, which resulted from the necessity of burying the owner. Cauldrons played an important role in the life of steppe leaders. The authors assume a sacral nature of the use of cauldrons in the culture of steppe peoples associated with feasts, battles, and sacred hunting. Perhaps, there was a tradition of burying cauldrons together with their owners after spoiling the items in view of the concept of the other world and the role of a heroic leader therein.

  8. Better assessment of physical function: item improvement is neglected but essential.

    Science.gov (United States)

    Bruce, Bonnie; Fries, James F; Ambrosini, Debbie; Lingala, Bharathi; Gandek, Barbara; Rose, Matthias; Ware, John E

    2009-01-01

    Physical function is a key component of patient-reported outcome (PRO) assessment in rheumatology. Modern psychometric methods, such as Item Response Theory (IRT) and Computerized Adaptive Testing, can materially improve measurement precision at the item level. We present the qualitative and quantitative item-evaluation process for developing the Patient Reported Outcomes Measurement Information System (PROMIS) Physical Function item bank. The process was stepwise: we searched extensively to identify extant Physical Function items and then classified and selectively reduced the item pool. We evaluated retained items for content, clarity, relevance and comprehension, reading level, and translation ease by experts and patient surveys, focus groups, and cognitive interviews. We then assessed items by using classic test theory and IRT, used confirmatory factor analyses to estimate item parameters, and graded response modeling for parameter estimation. We retained the 20 Legacy (original) Health Assessment Questionnaire Disability Index (HAQ-DI) and the 10 SF-36's PF-10 items for comparison. Subjects were from rheumatoid arthritis, osteoarthritis, and healthy aging cohorts (n = 1,100) and a national Internet sample of 21,133 subjects. We identified 1,860 items. After qualitative and quantitative evaluation, 124 newly developed PROMIS items composed the PROMIS item bank, which included revised Legacy items with good fit that met IRT model assumptions. Results showed that the clearest and best-understood items were simple, in the present tense, and straightforward. Basic tasks (like dressing) were more relevant and important versus complex ones (like dancing). Revised HAQ-DI and PF-10 items with five response options had higher item-information content than did comparable original Legacy items with fewer response options. IRT analyses showed that the Physical Function domain satisfied general criteria for unidimensionality with one-, two-, three-, and four-factor models

  9. Theoretical Studies of Aqueous Systems above 25 deg C. 1. Fundamental Concepts for Equilibrium Diagrams and some General Features of the Water System

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, Derek

    1971-09-15

    The illustration of thermodynamic data on aqueous systems is discussed and diagrams are described that are useful for bringing together the large numbers of data that are relevant to technological problems such as corrosion, mass-transport and deposition. Two kinds of logarithmic equilibrium diagram are particularly useful, namely, diagrams depicting the variation with pH or pe of the concentrations of ionic species relative to that of a chosen reference ion and diagrams depicting the fields of conditions of pH and pe in which the various species in any given system predominate or are stable. Such diagrams clearly and concisely illustrate the data and greatly simplify the comparison of the states of a system at different temperatures. Estimates of the equilibrium constants for the redox and the acid-base dissociation of water up to 375 C are reported and some general features of aqueous systems at elevated temperatures are discussed

  10. Trends in Sodium Content of Menu Items in Large Chain Restaurants in the U.S.

    Science.gov (United States)

    Wolfson, Julia A; Moran, Alyssa J; Jarlenski, Marian P; Bleich, Sara N

    2018-01-01

    Consuming too much sodium is associated with increased risk for cardiovascular disease, and restaurant foods are a primary source of sodium. This study assessed recent trends in sodium content of menu items in U.S. chain restaurants. Data from 21,557 menu items in 66 top-earning chain restaurants available from 2012 to 2016 were obtained from the MenuStat project and analyzed in 2017. Generalized linear models were used to examine changes in calorie-adjusted, per-item sodium content of menu items offered in all years (2012-2016) and items offered in 2012 only compared with items newly introduced in 2013, 2014, 2015, and 2016. Overall, calorie-adjusted sodium content in newly introduced menu items declined by 104 mg from 2012 to 2016 (prestaurant type; sodium content, particularly for main course items, was high. Sodium declined by 83 mg in fast food restaurants, 19 mg in fast casual restaurants, and 163 mg in full service restaurants. Sodium in appetizer and side items newly introduced in 2016 increased by 266 mg compared with items on the menu in 2012 only (prestaurants. However, sodium content of core and new menu items remain high, and reductions are inconsistent across menu categories and restaurant types. Copyright © 2018 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  11. Mathematical concepts

    CERN Document Server

    Jost, Jürgen

    2015-01-01

    The main intention of this book is to describe and develop the conceptual, structural and abstract thinking of mathematics. Specific mathematical structures are used to illustrate the conceptual approach; providing a deeper insight into mutual relationships and abstract common features. These ideas are carefully motivated, explained and illustrated by examples so that many of the more technical proofs can be omitted. The book can therefore be used: ·         simply as an overview of the panorama of mathematical structures and the relations between them, to be supplemented by more detailed texts whenever you want to acquire a working knowledge of some structure ·         by itself as a first introduction to abstract mathematics ·         together with existing textbooks, to put their results into a more general perspective ·         to gain a new and hopefully deeper perspective after having studied such textbooks Mathematical Concepts has a broader scope and is less detaile...

  12. CERN Running Club – Sale of Items

    CERN Multimedia

    CERN Running club

    2018-01-01

    The CERN Running Club is organising a sale of items  on 26 June from 11:30 – 13:00 in the entry area of Restaurant 2 (504 R-202). The items for sale are souvenir prizes of past Relay Races and comprise: Backpacks, thermos, towels, gloves & caps, lamps, long sleeve winter shirts and windproof vest. All items will be sold at 5 CHF.

  13. A confirmative clinimetric analysis of the 36-item Family Assessment Device.

    Science.gov (United States)

    Timmerby, Nina; Cosci, Fiammetta; Watson, Maggie; Csillag, Claudio; Schmitt, Florence; Steck, Barbara; Bech, Per; Thastum, Mikael

    2018-02-07

    The Family Assessment Device (FAD) is a 60-item questionnaire widely used to evaluate self-reported family functioning. However, the factor structure as well as the number of items has been questioned. A shorter and more user-friendly version of the original FAD-scale, the 36-item FAD, has therefore previously been proposed, based on findings in a nonclinical population of adults. We aimed in this study to evaluate the brief 36-item version of the FAD in a clinical population. Data from a European multinational study, examining factors associated with levels of family functioning in adult cancer patients' families, were used. Both healthy and ill parents completed the 60-item version FAD. The psychometric analyses conducted were Principal Component Analysis and Mokken-analysis. A total of 564 participants were included. Based on the psychometric analysis we confirmed that the 36-item version of the FAD has robust psychometric properties and can be used in clinical populations. The present analysis confirmed that the 36-item version of the FAD (18 items assessing 'well-being' and 18 items assessing 'dysfunctional' family function) is a brief scale where the summed total score is a valid measure of the dimensions of family functioning. This shorter version of the FAD is, in accordance with the concept of 'measurement-based care', an easy to use scale that could be considered when the aim is to evaluate self-reported family functioning.

  14. Automatic Item Generation via Frame Semantics: Natural Language Generation of Math Word Problems.

    Science.gov (United States)

    Deane, Paul; Sheehan, Kathleen

    This paper is an exploration of the conceptual issues that have arisen in the course of building a natural language generation (NLG) system for automatic test item generation. While natural language processing techniques are applicable to general verbal items, mathematics word problems are particularly tractable targets for natural language…

  15. 17 CFR 210.3A-04 - Intercompany items and transactions.

    Science.gov (United States)

    2010-04-01

    ... Financial Statements § 210.3A-04 Intercompany items and transactions. In general, there shall be eliminated intercompany items and transactions between persons included in the (a) consolidated financial statements being... FORM AND CONTENT OF AND REQUIREMENTS FOR FINANCIAL STATEMENTS, SECURITIES ACT OF 1933, SECURITIES...

  16. Quantifying Local, Response Dependence between Two Polytomous Items Using the Rasch Model

    Science.gov (United States)

    Andrich, David; Humphry, Stephen M.; Marais, Ida

    2012-01-01

    Models of modern test theory imply statistical independence among responses, generally referred to as "local independence." One violation of local independence occurs when the response to one item governs the response to a subsequent item. Expanding on a formulation of this kind of violation as a process in the dichotomous Rasch model,…

  17. Re-evaluating a vision-related quality of life questionnaire with item response theory (IRT and differential item functioning (DIF analyses

    Directory of Open Access Journals (Sweden)

    Knol Dirk L

    2011-09-01

    Full Text Available Abstract Background For the Low Vision Quality Of Life questionnaire (LVQOL it is unknown whether the psychometric properties are satisfactory when an item response theory (IRT perspective is considered. This study evaluates some essential psychometric properties of the LVQOL questionnaire in an IRT model, and investigates differential item functioning (DIF. Methods Cross-sectional data were used from an observational study among visually-impaired patients (n = 296. Calibration was performed for every dimension of the LVQOL in the graded response model. Item goodness-of-fit was assessed with the S-X2-test. DIF was assessed on relevant background variables (i.e. age, gender, visual acuity, eye condition, rehabilitation type and administration type with likelihood-ratio tests for DIF. The magnitude of DIF was interpreted by assessing the largest difference in expected scores between subgroups. Measurement precision was assessed by presenting test information curves; reliability with the index of subject separation. Results All items of the LVQOL dimensions fitted the model. There was significant DIF on several items. For two items the maximum difference between expected scores exceeded one point, and DIF was found on multiple relevant background variables. Item 1 'Vision in general' from the "Adjustment" dimension and item 24 'Using tools' from the "Reading and fine work" dimension were removed. Test information was highest for the "Reading and fine work" dimension. Indices for subject separation ranged from 0.83 to 0.94. Conclusions The items of the LVQOL showed satisfactory item fit to the graded response model; however, two items were removed because of DIF. The adapted LVQOL with 21 items is DIF-free and therefore seems highly appropriate for use in heterogeneous populations of visually impaired patients.

  18. The Effect of Visual Variability on the Learning of Academic Concepts.

    Science.gov (United States)

    Bourgoyne, Ashley; Alt, Mary

    2017-06-10

    The purpose of this study was to identify effects of variability of visual input on development of conceptual representations of academic concepts for college-age students with normal language (NL) and those with language-learning disabilities (LLD). Students with NL (n = 11) and LLD (n = 11) participated in a computer-based training for introductory biology course concepts. Participants were trained on half the concepts under a low-variability condition and half under a high-variability condition. Participants completed a posttest in which they were asked to identify and rate the accuracy of novel and trained visual representations of the concepts. We performed separate repeated measures analyses of variance to examine the accuracy of identification and ratings. Participants were equally accurate on trained and novel items in the high-variability condition, but were less accurate on novel items only in the low-variability condition. The LLD group showed the same pattern as the NL group; they were just less accurate. Results indicated that high-variability visual input may facilitate the acquisition of academic concepts in college students with NL and LLD. High-variability visual input may be especially beneficial for generalization to novel representations of concepts. Implicit learning methods may be harnessed by college courses to provide students with basic conceptual knowledge when they are entering courses or beginning new units.

  19. Explicitation in Translation: Culture-Specific Items from Persian into English

    OpenAIRE

    MORADI, Neda; RAHBAR, Muhamad; OLFATI, Mohsen

    2015-01-01

    Abstract. Investigating the concept of explicitation has been the center of attention to many scholars recent years. A lot of studies have been carried out dealing with the exploitation of explicitation on the culture-specific items on the translation of English source text into Persian. However, few studies has been carried out investigating such culture-specific items on Persian source text translated into English. The present article aims at providing sufficient data to cover the identific...

  20. Pregnancy-related anxiety: A concept analysis.

    Science.gov (United States)

    Bayrampour, Hamideh; Ali, Elena; McNeil, Deborah A; Benzies, Karen; MacQueen, Glenda; Tough, Suzanne

    2016-03-01

    Evidence suggests that pregnancy-related anxiety is more strongly associated with maternal and child outcomes than general anxiety and depression are and that pregnancy-related anxiety may constitute a distinct concept. However, because of its poor conceptualization, the measurement and assessment of pregnancy-related anxiety have been limited. Efforts to analyze this concept can significantly contribute to its theoretical development. The first objective of this paper was to clarify the concept of pregnancy-related anxiety and identify its characteristics and dimensions. The second aim was to examine the items of current pregnancy-related anxiety measures to determine the dimensions and attributes that each scale addresses, noting any gaps between the current assessment and the construct of the concept. A concept analysis was conducted to examine the concept of pregnancy-related anxiety. To obtain the relevant evidence, several databases were searched including MEDLINE, PsycINFO, EBSCO's SocINDEX, Psychological and Behavioral Sciences Collection, CINAHL, SCOPUS, and EMBASE. A modified approach based on Walker and Avant (Strategies for theory construction in nursing. 5th ed; 2011) was used. Qualitative or quantitative studies published in English that explored or examined anxiety during pregnancy or its dimensions prospectively or retrospectively were included. Thirty eight studies provided data for the concept analysis. Three critical attributes (i.e., affective responses, cognitions, and somatic symptoms), three antecedents (i.e., a real or anticipated threat to pregnancy or its outcomes, low perceived control, and excessive cognitive activity, and four consequences (i.e., negative attitudes, difficulty concentrating, excessive reassurance-seeking behavior, and avoidance behaviors) were identified. Nine dimensions for pregnancy-related anxiety were determined, and a definition of the concept was proposed. The most frequently reported dimensions included anxiety

  1. A musculoskeletal model of low grade connective tissue inflammation in patients with thyroid associated ophthalmopathy (TAO: the WOMED concept of lateral tension and its general implications in disease

    Directory of Open Access Journals (Sweden)

    Moncayo Helga

    2007-02-01

    to the contra lateral side and tendon snapping. We propose that eccentric muscle action over time can be the basis for a low grade inflammatory condition. The general implications of this model and its relations to Zn and Se will be discussed.

  2. Discussion on monitoring items of radionuclides in influents from nuclear power plants

    International Nuclear Information System (INIS)

    Zhang Yanxia; Li Jin; Liu Jiacheng; Han Shanbiao; Yu Zhengwei

    2014-01-01

    For the radionuclide monitoring items of effluents from nuclear power plant, this paper makes some comparisons and analysis from three aspects of the international atomic energy general requirements, the routine radionuclide measurement items of China's nuclear power plant and effluents low level radionuclide experimental research results. Finally, it summarizes the necessary items and recommended items of the radionuclide monitoring of effluents from nuclear power plant, which can provide references for the radioactivity monitoring activities of nuclear power plant effluent and the supervisions of regulatory departments. (authors)

  3. Applying Item Response Theory methods to design a learning progression-based science assessment

    Science.gov (United States)

    Chen, Jing

    Learning progressions are used to describe how students' understanding of a topic progresses over time and to classify the progress of students into steps or levels. This study applies Item Response Theory (IRT) based methods to investigate how to design learning progression-based science assessments. The research questions of this study are: (1) how to use items in different formats to classify students into levels on the learning progression, (2) how to design a test to give good information about students' progress through the learning progression of a particular construct and (3) what characteristics of test items support their use for assessing students' levels. Data used for this study were collected from 1500 elementary and secondary school students during 2009--2010. The written assessment was developed in several formats such as the Constructed Response (CR) items, Ordered Multiple Choice (OMC) and Multiple True or False (MTF) items. The followings are the main findings from this study. The OMC, MTF and CR items might measure different components of the construct. A single construct explained most of the variance in students' performances. However, additional dimensions in terms of item format can explain certain amount of the variance in student performance. So additional dimensions need to be considered when we want to capture the differences in students' performances on different types of items targeting the understanding of the same underlying progression. Items in each item format need to be improved in certain ways to classify students more accurately into the learning progression levels. This study establishes some general steps that can be followed to design other learning progression-based tests as well. For example, first, the boundaries between levels on the IRT scale can be defined by using the means of the item thresholds across a set of good items. Second, items in multiple formats can be selected to achieve the information criterion at all

  4. Gender fairness within the Force Concept Inventory

    Science.gov (United States)

    Traxler, Adrienne; Henderson, Rachel; Stewart, John; Stewart, Gay; Papak, Alexis; Lindell, Rebecca

    2018-01-01

    Research on the test structure of the Force Concept Inventory (FCI) has largely ignored gender, and research on FCI gender effects (often reported as "gender gaps") has seldom interrogated the structure of the test. These rarely crossed streams of research leave open the possibility that the FCI may not be structurally valid across genders, particularly since many reported results come from calculus-based courses where 75% or more of the students are men. We examine the FCI considering both psychometrics and gender disaggregation (while acknowledging this as a binary simplification), and find several problematic questions whose removal decreases the apparent gender gap. We analyze three samples (total Npre=5391 , Npost=5769 ) looking for gender asymmetries using classical test theory, item response theory, and differential item functioning. The combination of these methods highlights six items that appear substantially unfair to women and two items biased in favor of women. No single physical concept or prior experience unifies these questions, but they are broadly consistent with problematic items identified in previous research. Removing all significantly gender-unfair items halves the gender gap in the main sample in this study. We recommend that instructors using the FCI report the reduced-instrument score as well as the 30-item score, and that credit or other benefits to students not be assigned using the biased items.

  5. Gender fairness within the Force Concept Inventory

    Directory of Open Access Journals (Sweden)

    Adrienne Traxler

    2018-01-01

    Full Text Available Research on the test structure of the Force Concept Inventory (FCI has largely ignored gender, and research on FCI gender effects (often reported as “gender gaps” has seldom interrogated the structure of the test. These rarely crossed streams of research leave open the possibility that the FCI may not be structurally valid across genders, particularly since many reported results come from calculus-based courses where 75% or more of the students are men. We examine the FCI considering both psychometrics and gender disaggregation (while acknowledging this as a binary simplification, and find several problematic questions whose removal decreases the apparent gender gap. We analyze three samples (total N_{pre}=5391, N_{post}=5769 looking for gender asymmetries using classical test theory, item response theory, and differential item functioning. The combination of these methods highlights six items that appear substantially unfair to women and two items biased in favor of women. No single physical concept or prior experience unifies these questions, but they are broadly consistent with problematic items identified in previous research. Removing all significantly gender-unfair items halves the gender gap in the main sample in this study. We recommend that instructors using the FCI report the reduced-instrument score as well as the 30-item score, and that credit or other benefits to students not be assigned using the biased items.

  6. Item response theory, computerized adaptive testing, and PROMIS: assessment of physical function.

    Science.gov (United States)

    Fries, James F; Witter, James; Rose, Matthias; Cella, David; Khanna, Dinesh; Morgan-DeWitt, Esi

    2014-01-01

    Patient-reported outcome (PRO) questionnaires record health information directly from research participants because observers may not accurately represent the patient perspective. Patient-reported Outcomes Measurement Information System (PROMIS) is a US National Institutes of Health cooperative group charged with bringing PRO to a new level of precision and standardization across diseases by item development and use of item response theory (IRT). With IRT methods, improved items are calibrated on an underlying concept to form an item bank for a "domain" such as physical function (PF). The most informative items can be combined to construct efficient "instruments" such as 10-item or 20-item PF static forms. Each item is calibrated on the basis of the probability that a given person will respond at a given level, and the ability of the item to discriminate people from one another. Tailored forms may cover any desired level of the domain being measured. Computerized adaptive testing (CAT) selects the best items to sharpen the estimate of a person's functional ability, based on prior responses to earlier questions. PROMIS item banks have been improved with experience from several thousand items, and are calibrated on over 21,000 respondents. In areas tested to date, PROMIS PF instruments are superior or equal to Health Assessment Questionnaire and Medical Outcome Study Short Form-36 Survey legacy instruments in clarity, translatability, patient importance, reliability, and sensitivity to change. Precise measures, such as PROMIS, efficiently incorporate patient self-report of health into research, potentially reducing research cost by lowering sample size requirements. The advent of routine IRT applications has the potential to transform PRO measurement.

  7. Item response theory scoring and the detection of curvilinear relationships.

    Science.gov (United States)

    Carter, Nathan T; Dalal, Dev K; Guan, Li; LoPilato, Alexander C; Withrow, Scott A

    2017-03-01

    Psychologists are increasingly positing theories of behavior that suggest psychological constructs are curvilinearly related to outcomes. However, results from empirical tests for such curvilinear relations have been mixed. We propose that correctly identifying the response process underlying responses to measures is important for the accuracy of these tests. Indeed, past research has indicated that item responses to many self-report measures follow an ideal point response process-wherein respondents agree only to items that reflect their own standing on the measured variable-as opposed to a dominance process, wherein stronger agreement, regardless of item content, is always indicative of higher standing on the construct. We test whether item response theory (IRT) scoring appropriate for the underlying response process to self-report measures results in more accurate tests for curvilinearity. In 2 simulation studies, we show that, regardless of the underlying response process used to generate the data, using the traditional sum-score generally results in high Type 1 error rates or low power for detecting curvilinearity, depending on the distribution of item locations. With few exceptions, appropriate power and Type 1 error rates are achieved when dominance-based and ideal point-based IRT scoring are correctly used to score dominance and ideal point response data, respectively. We conclude that (a) researchers should be theory-guided when hypothesizing and testing for curvilinear relations; (b) correctly identifying whether responses follow an ideal point versus dominance process, particularly when items are not extreme is critical; and (c) IRT model-based scoring is crucial for accurate tests of curvilinearity. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  8. Marginal Maximum Likelihood Estimation of Item Response Models in R

    Directory of Open Access Journals (Sweden)

    Matthew S. Johnson

    2007-02-01

    Full Text Available Item response theory (IRT models are a class of statistical models used by researchers to describe the response behaviors of individuals to a set of categorically scored items. The most common IRT models can be classified as generalized linear fixed- and/or mixed-effect models. Although IRT models appear most often in the psychological testing literature, researchers in other fields have successfully utilized IRT-like models in a wide variety of applications. This paper discusses the three major methods of estimation in IRT and develops R functions utilizing the built-in capabilities of the R environment to find the marginal maximum likelihood estimates of the generalized partial credit model. The currently available R packages ltm is also discussed.

  9. Evaluation of psychometric properties and differential item functioning of 8-item Child Perceptions Questionnaires using item response theory.

    Science.gov (United States)

    Yau, David T W; Wong, May C M; Lam, K F; McGrath, Colman

    2015-08-19

    Four-factor structure of the two 8-item short forms of Child Perceptions Questionnaire CPQ11-14 (RSF:8 and ISF:8) has been confirmed. However, the sum scores are typically reported in practice as a proxy of Oral health-related Quality of Life (OHRQoL), which implied a unidimensional structure. This study first assessed the unidimensionality of 8-item short forms of CPQ11-14. Item response theory (IRT) was employed to offer an alternative and complementary approach of validation and to overcome the limitations of classical test theory assumptions. A random sample of 649 12-year-old school children in Hong Kong was analyzed. Unidimensionality of the scale was tested by confirmatory factor analysis (CFA), principle component analysis (PCA) and local dependency (LD) statistic. Graded response model was fitted to the data. Contribution of each item to the scale was assessed by item information function (IIF). Reliability of the scale was assessed by test information function (TIF). Differential item functioning (DIF) across gender was identified by Wald test and expected score functions. Both CPQ11-14 RSF:8 and ISF:8 did not deviate much from the unidimensionality assumption. Results from CFA indicated acceptable fit of the one-factor model. PCA indicated that the first principle component explained >30 % of the total variation with high factor loadings for both RSF:8 and ISF:8. Almost all LD statistic items suggesting little contribution of information to the scale and item removal caused little practical impact. Comparing the TIFs, RSF:8 showed slightly better information than ISF:8. In addition to oral symptoms items, the item "Concerned with what other people think" demonstrated a uniform DIF (p Items related to oral symptoms were not informative to OHRQoL and deletion of these items is suggested. The impact of DIF across gender on the overall score was minimal. CPQ11-14 RSF:8 performed slightly better than ISF:8 in measurement precision. The 6-item short forms

  10. 48 CFR 12.201 - General.

    Science.gov (United States)

    2010-10-01

    ... ACQUISITION OF COMMERCIAL ITEMS Special Requirements for the Acquisition of Commercial Items 12.201 General. Public Law 103-355 establishes special requirements for the acquisition of commercial items intended to more closely resemble those customarily used in the commercial marketplace. This subpart identifies...

  11. The Relationship among Self-Concept, Self-Efficacy, and Performance in Mathematics during Secondary School.

    Science.gov (United States)

    Pietsch, James; Walker, Richard; Chapman, Elaine

    2003-01-01

    Examines the relationship among self-concept, self-efficacy, and performance in mathematics among 416 high school students. Confirmatory factor analyses supported the existence of two self-concept components--a competency component and an affective component. Self-efficacy items and the competency items of self-concept also loaded on a single…

  12. 38 CFR 3.1606 - Transportation items.

    Science.gov (United States)

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Transportation items. 3... Burial Benefits § 3.1606 Transportation items. The transportation costs of those persons who come within... shipment. (6) Cost of transportation by common carrier including amounts paid as Federal taxes. (7) Cost of...

  13. Grouping of Items in Mobile Web Questionnaires

    Science.gov (United States)

    Mavletova, Aigul; Couper, Mick P.

    2016-01-01

    There is some evidence that a scrolling design may reduce breakoffs in mobile web surveys compared to a paging design, but there is little empirical evidence to guide the choice of the optimal number of items per page. We investigate the effect of the number of items presented on a page on data quality in two types of questionnaires: with or…

  14. Comparison on Computed Tomography using industrial items

    DEFF Research Database (Denmark)

    Angel, Jais Andreas Breusch; De Chiffre, Leonardo

    2014-01-01

    In a comparison involving 27 laboratories from 8 countries, measurements on two common industrial items, a polymer part and a metal part, were carried out using X-ray Computed Tomography. All items were measured using coordinate measuring machines before and after circulation, with reference...

  15. Factoring handedness data: I. Item analysis.

    Science.gov (United States)

    Messinger, H B; Messinger, M I

    1995-12-01

    Recently in this journal Peters and Murphy challenged the validity of factor analyses done on bimodal handedness data, suggesting instead that right- and left-handers be studied separately. But bimodality may be avoidable if attention is paid to Oldfield's questionnaire format and instructions for the subjects. Two characteristics appear crucial: a two-column LEFT-RIGHT format for the body of the instrument and what we call Oldfield's Admonition: not to indicate strong preference for handedness item, such as write, unless "... the preference is so strong that you would never try to use the other hand unless absolutely forced to...". Attaining unimodality of an item distribution would seem to overcome the objections of Peters and Murphy. In a 1984 survey in Boston we used Oldfield's ten-item questionnaire exactly as published. This produced unimodal item distributions. With reflection of the five-point item scale and a logarithmic transformation, we achieved a degree of normalization for the items. Two surveys elsewhere based on Oldfield's 20-item list but with changes in the questionnaire format and the instructions, yielded markedly different item distributions with peaks at each extreme and sometimes in the middle as well.

  16. Item Information in the Rasch Model

    NARCIS (Netherlands)

    Engelen, Ron J.H.; van der Linden, Willem J.; Oosterloo, Sebe J.

    1988-01-01

    Fisher's information measure for the item difficulty parameter in the Rasch model and its marginal and conditional formulations are investigated. It is shown that expected item information in the unconditional model equals information in the marginal model, provided the assumption of sampling

  17. Trace DNA Sampling Success from Evidence Items Commonly Encountered in Forensic Casework.

    Science.gov (United States)

    Dziak, Renata; Peneder, Amy; Buetter, Alicia; Hageman, Cecilia

    2018-05-01

    Trace DNA analysis is a significant part of a forensic laboratory's workload. Knowing optimal sampling strategies and item success rates for particular item types can assist in evidence selection and examination processes and shorten turnaround times. In this study, forensic short tandem repeat (STR) casework results were reviewed to determine how often STR profiles suitable for comparison were obtained from "handler" and "wearer" areas of 764 items commonly submitted for examination. One hundred and fifty-five (155) items obtained from volunteers were also sampled. Items were analyzed for best sampling location and strategy. For casework items, headwear and gloves provided the highest success rates. Experimentally, eyeglasses and earphones, T-shirts, fabric gloves and watches provided the highest success rates. Eyeglasses and latex gloves provided optimal results if the entire surfaces were swabbed. In general, at least 10%, and up to 88% of all trace DNA analyses resulted in suitable STR profiles for comparison. © 2017 American Academy of Forensic Sciences.

  18. Medial temporal lobe contributions to cued retrieval of items and contexts.

    Science.gov (United States)

    Hannula, Deborah E; Libby, Laura A; Yonelinas, Andrew P; Ranganath, Charan

    2013-10-01

    Several models have proposed that different regions of the medial temporal lobes contribute to different aspects of episodic memory. For instance, according to one view, the perirhinal cortex represents specific items, parahippocampal cortex represents information regarding the context in which these items were encountered, and the hippocampus represents item-context bindings. Here, we used event-related functional magnetic resonance imaging (fMRI) to test a specific prediction of this model-namely, that successful retrieval of items from context cues will elicit perirhinal recruitment and that successful retrieval of contexts from item cues will elicit parahippocampal cortex recruitment. Retrieval of the bound representation in either case was expected to elicit hippocampal engagement. To test these predictions, we had participants study several item-context pairs (i.e., pictures of objects and scenes, respectively), and then had them attempt to recall items from associated context cues and contexts from associated item cues during a scanned retrieval session. Results based on both univariate and multivariate analyses confirmed a role for hippocampus in content-general relational memory retrieval, and a role for parahippocampal cortex in successful retrieval of contexts from item cues. However, we also found that activity differences in perirhinal cortex were correlated with successful cued recall for both items and contexts. These findings provide partial support for the above predictions and are discussed with respect to several models of medial temporal lobe function. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Medial Temporal Lobe Contributions to Cued Retrieval of Items and Contexts

    Science.gov (United States)

    Hannula, Deborah E.; Libby, Laura A.; Yonelinas, Andrew P.; Ranganath, Charan

    2013-01-01

    Several models have proposed that different regions of the medial temporal lobes contribute to different aspects of episodic memory. For instance, according to one view, the perirhinal cortex represents specific items, parahippocampal cortex represents information regarding the context in which these items were encountered, and the hippocampus represents item-context bindings. Here, we used event-related functional magnetic resonance imaging (fMRI) to test a specific prediction of this model – namely, that successful retrieval of items from context cues will elicit perirhinal recruitment and that successful retrieval of contexts from item cues will elicit parahippocampal cortex recruitment. Retrieval of the bound representation in either case was expected to elicit hippocampal engagement. To test these predictions, we had participants study several item-context pairs (i.e., pictures of objects and scenes, respectively), and then had them attempt to recall items from associated context cues and contexts from associated item cues during a scanned retrieval session. Results based on both univariate and multivariate analyses confirmed a role for hippocampus in content-general relational memory retrieval, and a role for parahippocampal cortex in successful retrieval of contexts from item cues. However, we also found that activity differences in perirhinal cortex were correlated with successful cued recall for both items and contexts. These findings provide partial support for the above predictions and are discussed with respect to several models of medial temporal lobe function. PMID:23466350

  20. COMET concept

    International Nuclear Information System (INIS)

    Alsmeyer, H.; Tromm, W.

    1995-01-01

    Studies of the COMET core catcher concept developed for a future PWR have been continued. The concept is based on the spreading of a core melt on a sacrificial layer and its erosion, until a subsequent addition of water from below causes a fragmentation of the melt. A porous solidification of the melt would then admit a complete flooding within a short period. (orig.)

  1. Concept Mapping

    Science.gov (United States)

    Technology & Learning, 2005

    2005-01-01

    Concept maps are graphical ways of working with ideas and presenting information. They reveal patterns and relationships and help students to clarify their thinking, and to process, organize and prioritize. Displaying information visually--in concept maps, word webs, or diagrams--stimulates creativity. Being able to think logically teaches…

  2. Management concepts.

    Science.gov (United States)

    Bittner, Rhonda

    2006-01-01

    Management concepts evolve through time. Health care managers can learn new concepts by evaluating classical management strategies, as well as modern-day strategies. Focusing on quality improvement and team building can help managers align the goals of their departments with the goals of the organization, consequently improving patient care.

  3. Lateral Concepts

    DEFF Research Database (Denmark)

    Gad, Christopher; Bruun Jensen, casper

    2016-01-01

    This essay discusses the complex relation between the knowledges and practices of the researcher and his/her informants in terms of lateral concepts. The starting point is that it is not the prerogative of the (STS) scholar to conceptualize the world; all our “informants” do it too. This creates...... the possibility of enriching our own conceptual repertoires by letting them be inflected by the concepts of those we study. In a broad sense, the lateral means that there is a many-to-many relation between domains of knowledge and practice. However, each specific case of the lateral is necessarily immanent...... to a particular empirical setting and form of inquiry. In this sense lateral concepts are radically empirical since it locates concepts within the field. To clarify the meaning and stakes of lateral concepts, we first make a contrast between lateral anthropology and Latour’s notion of infra-reflexivity. We end...

  4. Concept theory

    DEFF Research Database (Denmark)

    Hjørland, Birger

    2009-01-01

      Concept theory is an extremely broad, interdisciplinary and complex field of research related to many deep fields with very long historical traditions without much consensus. However, information science and knowledge organization cannot avoid relating to theories of concepts. Knowledge...... organizing systems (e.g. classification systems, thesauri and ontologies) should be understood as systems basically organizing concepts and their semantic relations. The same is the case with information retrieval systems. Different theories of concepts have different implications for how to construe......, evaluate and use such systems. Based on "a post-Kuhnian view" of paradigms this paper put forward arguments that the best understanding and classification of theories of concepts is to view and classify them in accordance with epistemological theories (empiricism, rationalism, historicism and pragmatism...

  5. Automatic item generation implemented for measuring artistic judgment aptitude.

    Science.gov (United States)

    Bezruczko, Nikolaus

    2014-01-01

    Automatic item generation (AIG) is a broad class of methods that are being developed to address psychometric issues arising from internet and computer-based testing. In general, issues emphasize efficiency, validity, and diagnostic usefulness of large scale mental testing. Rapid prominence of AIG methods and their implicit perspective on mental testing is bringing painful scrutiny to many sacred psychometric assumptions. This report reviews basic AIG ideas, then presents conceptual foundations, image model development, and operational application to artistic judgment aptitude testing.

  6. More items on visitors' menu

    CERN Document Server

    2005-01-01

    Visitors to CERN will now be able to appreciate first-hand the sheer scale of the computing challenge associated with the LHC, during guided visits to the Computing Centre. Two more of CERN's experimental facilities have recently been added to the itineraries offered to the public by the Visits Service. The general public will now be able to see the COMPASS experiment and CERN's Computing Centre. Over the past few years, there has been an increasing demand for visits. Last year, 25 000 visitors came to see sites at CERN. 'Visitors to CERN are impressed by the sheer scale of the experiments, interested to find out how they work and amazed at how they are often located underground,' says Dominique Bertola, Head of the CERN Visits Service. COMPASS is the first fixed-target experiment available for viewing to the general public. The linear structure of the detector makes it an ideal exhibit for the visitors, because it permits them to see the different stages of the experiment and intuitively appreciate how it ...

  7. Software Note: Using BILOG for Fixed-Anchor Item Calibration

    Science.gov (United States)

    DeMars, Christine E.; Jurich, Daniel P.

    2012-01-01

    The nonequivalent groups anchor test (NEAT) design is often used to scale item parameters from two different test forms. A subset of items, called the anchor items or common items, are administered as part of both test forms. These items are used to adjust the item calibrations for any differences in the ability distributions of the groups taking…

  8. Computerized Adaptive Test (CAT) Applications and Item Response Theory Models for Polytomous Items

    Science.gov (United States)

    Aybek, Eren Can; Demirtasli, R. Nukhet

    2017-01-01

    This article aims to provide a theoretical framework for computerized adaptive tests (CAT) and item response theory models for polytomous items. Besides that, it aims to introduce the simulation and live CAT software to the related researchers. Computerized adaptive test algorithm, assumptions of item response theory models, nominal response…

  9. Evaluation of Northwest University, Kano Post-UTME Test Items Using Item Response Theory

    Science.gov (United States)

    Bichi, Ado Abdu; Hafiz, Hadiza; Bello, Samira Abdullahi

    2016-01-01

    High-stakes testing is used for the purposes of providing results that have important consequences. Validity is the cornerstone upon which all measurement systems are built. This study applied the Item Response Theory principles to analyse Northwest University Kano Post-UTME Economics test items. The developed fifty (50) economics test items was…

  10. Asymptotic Standard Errors for Item Response Theory True Score Equating of Polytomous Items

    Science.gov (United States)

    Cher Wong, Cheow

    2015-01-01

    Building on previous works by Lord and Ogasawara for dichotomous items, this article proposes an approach to derive the asymptotic standard errors of item response theory true score equating involving polytomous items, for equivalent and nonequivalent groups of examinees. This analytical approach could be used in place of empirical methods like…

  11. The Effects of Test Length and Sample Size on Item Parameters in Item Response Theory

    Science.gov (United States)

    Sahin, Alper; Anil, Duygu

    2017-01-01

    This study investigates the effects of sample size and test length on item-parameter estimation in test development utilizing three unidimensional dichotomous models of item response theory (IRT). For this purpose, a real language test comprised of 50 items was administered to 6,288 students. Data from this test was used to obtain data sets of…

  12. Investigating Separate and Concurrent Approaches for Item Parameter Drift in 3PL Item Response Theory Equating

    Science.gov (United States)

    Arce-Ferrer, Alvaro J.; Bulut, Okan

    2017-01-01

    This study examines separate and concurrent approaches to combine the detection of item parameter drift (IPD) and the estimation of scale transformation coefficients in the context of the common item nonequivalent groups design with the three-parameter item response theory equating. The study uses real and synthetic data sets to compare the two…

  13. The Technical Quality of Test Items Generated Using a Systematic Approach to Item Writing.

    Science.gov (United States)

    Siskind, Theresa G.; Anderson, Lorin W.

    The study was designed to examine the similarity of response options generated by different item writers using a systematic approach to item writing. The similarity of response options to student responses for the same item stems presented in an open-ended format was also examined. A non-systematic (subject matter expertise) approach and a…

  14. Calorie Changes in Large Chain Restaurants: Declines in New Menu Items but Room for Improvement.

    Science.gov (United States)

    Bleich, Sara N; Wolfson, Julia A; Jarlenski, Marian P

    2016-01-01

    Large chain restaurants reduced the number of calories in newly introduced menu items in 2013 by about 60 calories (or 12%) relative to 2012. This paper describes trends in calories available in large U.S. chain restaurants to understand whether previously documented patterns persist. Data (a census of items for included restaurants) were obtained from the MenuStat project. This analysis included 66 of the 100 largest U.S. restaurants that are available in all three of the data years (2012-2014; N=23,066 items). Generalized linear models were used to examine: (1) per-item calorie changes from 2012 to 2014 among items on the menu in all years; and (2) mean calories in new items in 2013 and 2014 compared with items on the menu in 2012 only. Data were analyzed in 2014. Overall, calories in newly introduced menu items declined by 71 (or 15%) from 2012 to 2013 (p=0.001) and by 69 (or 14%) from 2012 to 2014 (p=0.03). These declines were concentrated mainly in new main course items (85 fewer calories in 2013 and 55 fewer calories in 2014; p=0.01). Although average calories in newly introduced menu items are declining, they are higher than items common to the menu in all 3 years. No differences in mean calories among items on menus in 2012, 2013, or 2014 were found. The previously observed declines in newly introduced menu items among large restaurant chains have been maintained, which suggests the beginning of a trend toward reducing calories. Copyright © 2016 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  15. Automated Item Generation with Recurrent Neural Networks.

    Science.gov (United States)

    von Davier, Matthias

    2018-03-12

    Utilizing technology for automated item generation is not a new idea. However, test items used in commercial testing programs or in research are still predominantly written by humans, in most cases by content experts or professional item writers. Human experts are a limited resource and testing agencies incur high costs in the process of continuous renewal of item banks to sustain testing programs. Using algorithms instead holds the promise of providing unlimited resources for this crucial part of assessment development. The approach presented here deviates in several ways from previous attempts to solve this problem. In the past, automatic item generation relied either on generating clones of narrowly defined item types such as those found in language free intelligence tests (e.g., Raven's progressive matrices) or on an extensive analysis of task components and derivation of schemata to produce items with pre-specified variability that are hoped to have predictable levels of difficulty. It is somewhat unlikely that researchers utilizing these previous approaches would look at the proposed approach with favor; however, recent applications of machine learning show success in solving tasks that seemed impossible for machines not too long ago. The proposed approach uses deep learning to implement probabilistic language models, not unlike what Google brain and Amazon Alexa use for language processing and generation.

  16. Bone marrow edema in sports: General concepts

    International Nuclear Information System (INIS)

    Vanhoenacker, F.M.; Snoeckx, A.

    2007-01-01

    This paper will discuss the value of medical imaging in the detection and follow-up of bone marrow edema (BME), resulting from acute and chronic trauma in sports. MR imaging is the only imaging technique that allows direct evaluation of bone marrow edema in sports medicine. The use of fat suppressed T2-weighted or STIR images is particularly appropriate to detect bone marrow edema. The extent of bone marrow edema reflects the biomechanics of trauma. Compressive forces between two bony structures will result in extensive areas of bone marrow edema, whereas distraction forces provoke more subtle areas of bone marrow edema at the insertion of supporting structures of joints. In most clinical situations, a combination of compression and distraction forces is present, causing a complex pattern of bone marrow edema. A meticulous pattern approach of the distribution of these bone marrow changes around a joint can reveal in most instances the underlying mechanism of trauma. This may be helpful to analyze which joint supporting structures may be at risk. In the acute setting, plain radiography and CT scan may have an additional role in the detection of small avulsion fractures occurring at the site of minor areas of bone marrow edema. The clinical significance and natural history of bone marrow edema is still a matter of debate

  17. General concept of wound healing, revisited

    Directory of Open Access Journals (Sweden)

    Theddeus O.H. Prasetyono

    2009-09-01

    Full Text Available Wound healing is a transition of processes which is also recognized as one of the most complex processes in human physiology. Complex series of reactions and interactions among cells and mediators take place in the healing process of wound involving cellular and molecular events. The inflammatory phase is naturally intended to remove devitalized tissue and prevent invasive infection. The proliferative phase is characterized by the formation of granulation tissue within the wound bed, composed of new capillary network, fibroblast, and macrophages in a loose arrangement of supporting structure. This second phase lasts from day 8 to 21 after the injury is also the phase for epithelialisation. The natural period of proliferative phase is a reflection for us in treating wound to reach the goal which ultimately defines as closed wound. The final maturation phase is also characterized by the balancing between deposition of collagen and its degradation. There are at least three prerequisites which are ideal local conditions for the nature of wound to go on a normal process of healing i.e. 1 all tissue involved in the wound and surrounding should be vital, 2 no foreign bodies in the wound, and 3 free from excessive contamination/infection. The author formulated a step ladder of thinking in regards of healing intentions covering all acute and chronic wounds. Regarding the “hierarchy” of healing intention, the fi rst and ideal choice to heal wounds is by primary intention followed by tertiary intention and lastly the secondary intention. (Med J Indones 2009;18:206-14Key words: inflammatory mediator, epithelialisation, growth factor, wound healing

  18. General Concepts in Adult Congenital Heart Disease.

    Science.gov (United States)

    Mutluer, Ferit Onur; Çeliker, Alpay

    2018-01-20

    Congenital heart disease in adults (adult congenital heart disease) is a growing burden for healthcare systems. While infant mortality due to congenital heart disease in the last four decades decreased by almost 3-fold, adult congenital heart disease prevalence increased by more than 2-fold in United States. Adult congenital heart disease prevalence is expected to increase steadily until 2050 in projections. Adult congenital heart disease is a multifaceted problem with many dimensions. This manuscript aims to provide an overview of the common adult congenital heart diseases and summarize important points in management of these diseases with possible problems and complications that the patients and the physicians face.

  19. General Concepts in Adult Congenital Heart Disease

    Directory of Open Access Journals (Sweden)

    Ferit Onur Mutluer

    2018-02-01

    Full Text Available Congenital heart disease in adults (adult congenital heart disease is a growing burden for healthcare systems. While infant mortality due to congenital heart disease in the last four decades decreased by almost 3-fold, adult congenital heart disease prevalence increased by more than 2-fold in United States. Adult congenital heart disease prevalence is expected to increase steadily until 2050 in projections. Adult congenital heart disease is a multifaceted problem with many dimensions. This manuscript aims to provide an overview of the common adult congenital heart diseases and summarize important points in management of these diseases with possible problems and complications that the patients and the physicians face

  20. Assessment of fuel concepts

    International Nuclear Information System (INIS)

    Bailey, W.J.; Barner, J.O.

    1978-01-01

    The relative merits of various LWR UO 2 fuel concepts with the potential for improved power-ramping capability were qualitatively assessed. In the evaluation, it was determined that of the various concepts being considered, those that presently possess an adequately developed experience base include annular pellets, cladding coated with graphite on the inner surface, and packed-particle fuel. Therefore, these were selected for initial evaluation as part of the Fuel Performance Improvement Program. For this program, graphite-coated cladding is being used in conjunction with annular pellet fuel as one of the concepts with the anticipation of gaining the advantage of the combined improvements. The report discusses the following: the criteria used to evaluate the candidate fuel concepts; a comparison of the concepts selected for irradiation with the criteria, including a general description of their experience bases; and a general discussion of other candidate concepts, including identifying those which may be considered for out-of-reactor evaluation as part of this program, those for which the results of other programs will be monitored, and those which have been deleted from further consideration at this time

  1. Travelling Concepts

    DEFF Research Database (Denmark)

    Simonsen, Karen-Margrethe

    2013-01-01

    Review of "Travelling Concepts, Metaphors, and Narratives: Literary and Cultural Studies in an Age of Interdisciplinary Research" ed. by Sibylle Baumgarten, Beatrice Michaelis and Ansagar Nünning, Trier; Wissenschaftlicher Verlag Trier, 2012......Review of "Travelling Concepts, Metaphors, and Narratives: Literary and Cultural Studies in an Age of Interdisciplinary Research" ed. by Sibylle Baumgarten, Beatrice Michaelis and Ansagar Nünning, Trier; Wissenschaftlicher Verlag Trier, 2012...

  2. Development and Validation of the Homeostasis Concept Inventory

    Science.gov (United States)

    McFarland, Jenny L.; Price, Rebecca M.; Wenderoth, Mary Pat; Martinková, Patrícia; Cliff, William; Michael, Joel; Modell, Harold; Wright, Ann

    2017-01-01

    We present the Homeostasis Concept Inventory (HCI), a 20-item multiple-choice instrument that assesses how well undergraduates understand this critical physiological concept. We used an iterative process to develop a set of questions based on elements in the Homeostasis Concept Framework. This process involved faculty experts and undergraduate…

  3. Unsupervised Learning and Generalization

    DEFF Research Database (Denmark)

    Hansen, Lars Kai; Larsen, Jan

    1996-01-01

    The concept of generalization is defined for a general class of unsupervised learning machines. The generalization error is a straightforward extension of the corresponding concept for supervised learning, and may be estimated empirically using a test set or by statistical means-in close analogy ...... with supervised learning. The empirical and analytical estimates are compared for principal component analysis and for K-means clustering based density estimation......The concept of generalization is defined for a general class of unsupervised learning machines. The generalization error is a straightforward extension of the corresponding concept for supervised learning, and may be estimated empirically using a test set or by statistical means-in close analogy...

  4. NHRIC (National Health Related Items Code)

    Data.gov (United States)

    U.S. Department of Health & Human Services — The National Health Related Items Code (NHRIC) is a system for identification and numbering of marketed device packages that is compatible with other numbering...

  5. Basic Stand Alone Carrier Line Items PUF

    Data.gov (United States)

    U.S. Department of Health & Human Services — This release contains the Basic Stand Alone (BSA) Carrier Line Items Public Use Files (PUF) with information from Medicare Carrier claims. The CMS BSA Carrier Line...

  6. Extending item response theory to online homework

    Directory of Open Access Journals (Sweden)

    Gerd Kortemeyer

    2014-05-01

    Full Text Available Item response theory (IRT becomes an increasingly important tool when analyzing “big data” gathered from online educational venues. However, the mechanism was originally developed in traditional exam settings, and several of its assumptions are infringed upon when deployed in the online realm. For a large-enrollment physics course for scientists and engineers, the study compares outcomes from IRT analyses of exam and homework data, and then proceeds to investigate the effects of each confounding factor introduced in the online realm. It is found that IRT yields the correct trends for learner ability and meaningful item parameters, yet overall agreement with exam data is moderate. It is also found that learner ability and item discrimination is robust over a wide range with respect to model assumptions and introduced noise. Item difficulty is also robust, but over a narrower range.

  7. Two Conceptions of Virtue

    Science.gov (United States)

    Hill, Thomas E., Jr.

    2013-01-01

    The general questions are: what is virtue and how can it be cultivated? The specific focus is on the conceptions of virtue in the works of Immanuel Kant and John Rawls. Kant regarded virtue as a good will that is also strong enough to resist contrary passions, impulses, and inclinations. Childhood training can prepare children for virtue, but…

  8. Inventions on presenting textual items in Graphical User Interface

    OpenAIRE

    Mishra, Umakant

    2014-01-01

    Although a GUI largely replaces textual descriptions by graphical icons, the textual items are not completely removed. The textual items are inevitably used in window titles, message boxes, help items, menu items and popup items. Textual items are necessary for communicating messages that are beyond the limitation of graphical messages. However, it is necessary to harness the textual items on the graphical interface in such a way that they complement each other to produce the best effect. One...

  9. Assessment of the Item Selection and Weighting in the Birmingham Vasculitis Activity Score for Wegener's Granulomatosis

    Science.gov (United States)

    MAHR, ALFRED D.; NEOGI, TUHINA; LAVALLEY, MICHAEL P.; DAVIS, JOHN C.; HOFFMAN, GARY S.; MCCUNE, W. JOSEPH; SPECKS, ULRICH; SPIERA, ROBERT F.; ST.CLAIR, E. WILLIAM; STONE, JOHN H.; MERKEL, PETER A.

    2013-01-01

    Objective To assess the Birmingham Vasculitis Activity Score for Wegener's Granulomatosis (BVAS/WG) with respect to its selection and weighting of items. Methods This study used the BVAS/WG data from the Wegener's Granulomatosis Etanercept Trial. The scoring frequencies of the 34 predefined items and any “other” items added by clinicians were calculated. Using linear regression with generalized estimating equations in which the physician global assessment (PGA) of disease activity was the dependent variable, we computed weights for all predefined items. We also created variables for clinical manifestations frequently added as other items, and computed weights for these as well. We searched for the model that included the items and their generated weights yielding an activity score with the highest R2 to predict the PGA. Results We analyzed 2,044 BVAS/WG assessments from 180 patients; 734 assessments were scored during active disease. The highest R2 with the PGA was obtained by scoring WG activity based on the following items: the 25 predefined items rated on ≥5 visits, the 2 newly created fatigue and weight loss variables, the remaining minor other and major other items, and a variable that signified whether new or worse items were present at a specific visit. The weights assigned to the items ranged from 1 to 21. Compared with the original BVAS/WG, this modified score correlated significantly more strongly with the PGA. Conclusion This study suggests possibilities to enhance the item selection and weighting of the BVAS/WG. These changes may increase this instrument's ability to capture the continuum of disease activity in WG. PMID:18512722

  10. Calorie changes in chain restaurant menu items: implications for obesity and evaluations of menu labeling.

    Science.gov (United States)

    Bleich, Sara N; Wolfson, Julia A; Jarlenski, Marian P

    2015-01-01

    Supply-side reductions to the calories in chain restaurants are a possible benefit of upcoming menu labeling requirements. To describe trends in calories available in large U.S. restaurants. Data were obtained from the MenuStat project, a census of menu items in 66 of the 100 largest U.S. restaurant chains, for 2012 and 2013 (N=19,417 items). Generalized linear models were used to calculate (1) the mean change in calories from 2012 to 2013, among items on the menu in both years; and (2) the difference in mean calories, comparing newly introduced items to those on the menu in 2012 only (overall and between core versus non-core items). Data were analyzed in 2014. Mean calories among items on menus in both 2012 and 2013 did not change. Large restaurant chains in the U.S. have recently had overall declines in calories in newly introduced menu items (-56 calories, 12% decline). These declines were concentrated mainly in new main course items (-67 calories, 10% decline). New beverage (-26 calories, 8% decline) and children's (-46 calories, 20% decline) items also had fewer mean calories. Among chain restaurants with a specific focus (e.g., burgers), average calories in new menu items not core to the business declined more than calories in core menu items. Large chain restaurants significantly reduced the number of calories in newly introduced menu items. Supply-side changes to the calories in chain restaurants may have a significant impact on obesity prevention. Copyright © 2015 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  11. Item selection via Bayesian IRT models.

    Science.gov (United States)

    Arima, Serena

    2015-02-10

    With reference to a questionnaire that aimed to assess the quality of life for dysarthric speakers, we investigate the usefulness of a model-based procedure for reducing the number of items. We propose a mixed cumulative logit model, which is known in the psychometrics literature as the graded response model: responses to different items are modelled as a function of individual latent traits and as a function of item characteristics, such as their difficulty and their discrimination power. We jointly model the discrimination and the difficulty parameters by using a k-component mixture of normal distributions. Mixture components correspond to disjoint groups of items. Items that belong to the same groups can be considered equivalent in terms of both difficulty and discrimination power. According to decision criteria, we select a subset of items such that the reduced questionnaire is able to provide the same information that the complete questionnaire provides. The model is estimated by using a Bayesian approach, and the choice of the number of mixture components is justified according to information criteria. We illustrate the proposed approach on the basis of data that are collected for 104 dysarthric patients by local health authorities in Lecce and in Milan. Copyright © 2014 John Wiley & Sons, Ltd.

  12. The role of attention in item-item binding in visual working memory.

    Science.gov (United States)

    Peterson, Dwight J; Naveh-Benjamin, Moshe

    2017-09-01

    An important yet unresolved question regarding visual working memory (VWM) relates to whether or not binding processes within VWM require additional attentional resources compared with processing solely the individual components comprising these bindings. Previous findings indicate that binding of surface features (e.g., colored shapes) within VWM is not demanding of resources beyond what is required for single features. However, it is possible that other types of binding, such as the binding of complex, distinct items (e.g., faces and scenes), in VWM may require additional resources. In 3 experiments, we examined VWM item-item binding performance under no load, articulatory suppression, and backward counting using a modified change detection task. Binding performance declined to a greater extent than single-item performance under higher compared with lower levels of concurrent load. The findings from each of these experiments indicate that processing item-item bindings within VWM requires a greater amount of attentional resources compared with single items. These findings also highlight an important distinction between the role of attention in item-item binding within VWM and previous studies of long-term memory (LTM) where declines in single-item and binding test performance are similar under divided attention. The current findings provide novel evidence that the specific type of binding is an important determining factor regarding whether or not VWM binding processes require attention. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  13. Investigating the Impact of Item Parameter Drift for Item Response Theory Models with Mixture Distributions.

    Science.gov (United States)

    Park, Yoon Soo; Lee, Young-Sun; Xing, Kuan

    2016-01-01

    This study investigates the impact of item parameter drift (IPD) on parameter and ability estimation when the underlying measurement model fits a mixture distribution, thereby violating the item invariance property of unidimensional item response theory (IRT) models. An empirical study was conducted to demonstrate the occurrence of both IPD and an underlying mixture distribution using real-world data. Twenty-one trended anchor items from the 1999, 2003, and 2007 administrations of Trends in International Mathematics and Science Study (TIMSS) were analyzed using unidimensional and mixture IRT models. TIMSS treats trended anchor items as invariant over testing administrations and uses pre-calibrated item parameters based on unidimensional IRT. However, empirical results showed evidence of two latent subgroups with IPD. Results also showed changes in the distribution of examinee ability between latent classes over the three administrations. A simulation study was conducted to examine the impact of IPD on the estimation of ability and item parameters, when data have underlying mixture distributions. Simulations used data generated from a mixture IRT model and estimated using unidimensional IRT. Results showed that data reflecting IPD using mixture IRT model led to IPD in the unidimensional IRT model. Changes in the distribution of examinee ability also affected item parameters. Moreover, drift with respect to item discrimination and distribution of examinee ability affected estimates of examinee ability. These findings demonstrate the need to caution and evaluate IPD using a mixture IRT framework to understand its effects on item parameters and examinee ability.

  14. Investigating the Impact of Item Parameter Drift for Item Response Theory Models with Mixture Distributions

    Directory of Open Access Journals (Sweden)

    Yoon Soo ePark

    2016-02-01

    Full Text Available This study investigates the impact of item parameter drift (IPD on parameter and ability estimation when the underlying measurement model fits a mixture distribution, thereby violating the item invariance property of unidimensional item response theory (IRT models. An empirical study was conducted to demonstrate the occurrence of both IPD and an underlying mixture distribution using real-world data. Twenty-one trended anchor items from the 1999, 2003, and 2007 administrations of Trends in International Mathematics and Science Study (TIMSS were analyzed using unidimensional and mixture IRT models. TIMSS treats trended anchor items as invariant over testing administrations and uses pre-calibrated item parameters based on unidimensional IRT. However, empirical results showed evidence of two latent subgroups with IPD. Results showed changes in the distribution of examinee ability between latent classes over the three administrations. A simulation study was conducted to examine the impact of IPD on the estimation of ability and item parameters, when data have underlying mixture distributions. Simulations used data generated from a mixture IRT model and estimated using unidimensional IRT. Results showed that data reflecting IPD using mixture IRT model led to IPD in the unidimensional IRT model. Changes in the distribution of examinee ability also affected item parameters. Moreover, drift with respect to item discrimination and distribution of examinee ability affected estimates of examinee ability. These findings demonstrate the need to caution and evaluate IPD using a mixture IRT framework to understand its effect on item parameters and examinee ability.

  15. An ascending multi-item auction with financially constrained bidders

    Directory of Open Access Journals (Sweden)

    Gerard van der Laan

    2016-12-01

    Full Text Available Several heterogeneous items are to be sold to a group of potentially budget- constrained bidders. Every bidder has private knowledge of his own valuation of the items and his own budget. Due to budget constraints, bidders may not be able to pay up to their values and typically no Walrasian equilibrium exists. To deal with such markets, we propose the notion of 'equilibrium under allotment' and develop an ascending auction mechanism that always finds such an equilibrium assignment and a corresponding system of prices in finite time. The auction can be viewed as a novel generalization of the ascending auction of Demange et al. (1986 from settings without financial constraints to settings with financial constraints. We examine various strategic and efficiency properties of the auction and its outcome.

  16. Evaluation of item candidates for a diabetic retinopathy quality of life item bank.

    Science.gov (United States)

    Fenwick, Eva K; Pesudovs, Konrad; Khadka, Jyoti; Rees, Gwyn; Wong, Tien Y; Lamoureux, Ecosse L

    2013-09-01

    We are developing an item bank assessing the impact of diabetic retinopathy (DR) on quality of life (QoL) using a rigorous multi-staged process combining qualitative and quantitative methods. We describe here the first two qualitative phases: content development and item evaluation. After a comprehensive literature review, items were generated from four sources: (1) 34 previously validated patient-reported outcome measures; (2) five published qualitative articles; (3) eight focus groups and 18 semi-structured interviews with 57 DR patients; and (4) seven semi-structured interviews with diabetes or ophthalmic experts. Items were then evaluated during 3 stages, namely binning (grouping) and winnowing (reduction) based on key criteria and panel consensus; development of item stems and response options; and pre-testing of items via cognitive interviews with patients. The content development phase yielded 1,165 unique items across 7 QoL domains. After 3 sessions of binning and winnowing, items were reduced to a minimally representative set (n = 312) across 9 domains of QoL: visual symptoms; ocular surface symptoms; activity limitation; mobility; emotional; health concerns; social; convenience; and economic. After 8 cognitive interviews, 42 items were amended resulting in a final set of 314 items. We have employed a systematic approach to develop items for a DR-specific QoL item bank. The psychometric properties of the nine QoL subscales will be assessed using Rasch analysis. The resulting validated item bank will allow clinicians and researchers to better understand the QoL impact of DR and DR therapies from the patient's perspective.

  17. Design optimization of general arrangement in Korean next generation reactor

    International Nuclear Information System (INIS)

    Kim, S. H.; Jung, D. W.; Choi, Y. B.; Cho, S. J.

    1999-01-01

    In order to optimize the general arrangement(GA) of Korean Next Generation Reactor (KNGR), field opinions in domestic nuclear power plants have been collected, and the bench marking on UCN No.1,2 which were estimated to be the most excellent in view of operability and maintenance has been accomplished. Through this work, design optimization items for GA were reviewed. Major items to be selected for optimization are summarized as follows; 'Expanding the compound building function and the mezzanine floor concept in the auxiliary building', 'Including the diesel generator building to the auxiliary building', 'Change of the equipment removal method in the auxiliary building'. With these GA design optimization, the auxiliary building boundary will be improved as a complete rectangular type. The power block volume except the changing effect to the single containment structure will be reduced to about 10% in comparison with that of in KNGR phase II

  18. Family Relationships and Adolescent Self-Concept.

    Science.gov (United States)

    Massey, Catherine J.

    Previous research relating the quality of the relationship with the mother, father, and sibling to adolescent self-concept only investigated social and general self-concept and not various social and cognitive dimensions of self-concept. This study investigated family relationships and their link to the several domains of self-concept.…

  19. Comparison of seismic isolation concepts for FBR

    International Nuclear Information System (INIS)

    Shiojiri, H.; Mazda, T.; Kasai, H.; Kanda, J.N.; Kubo, T.; Madokoro, M.; Shimomura, T.; Nojima, O.

    1989-01-01

    This paper seeks to verify the reliability and effectiveness of seismic isolation for FBR. Some results of the preliminary study of the program are described. Seismic isolation concepts and corresponding seismic isolation devices were selected. Three kinds of seismically-isolated FBR plant concepts were developed by applying promising seismic isolation concepts to the non-isolated FBR plant, and by developing plant component layout plans and building structural designs. Each plant was subjected to seismic response analysis and reduction in the amount of material of components and buildings were estimated for each seismic isolation concepts. Research and development items were evaluated

  20. Analysis of Culture-Specific Items and Translation Strategies Applied in Translating Jalal Al-Ahmad's "By the Pen"

    Science.gov (United States)

    Daghoughi, Shekoufeh; Hashemian, Mahmood

    2016-01-01

    Due to differences across languages, meanings and concepts vary across different languages, too. The most obvious points of difference between languages appear in their literature and their culture-specific items (CSIs), which lead to complexities when transferring meanings and concepts from one language into another. To overcome the complexities…

  1. What Form of Mathematics Are Assessments Assessing? The Case of Multiplication and Division in Fourth Grade NAEP Items

    Science.gov (United States)

    Kosko Karl W.; Singh, Rashmi

    2018-01-01

    Multiplicative reasoning is a key concept in elementary school mathematics. Item statistics reported by the National Assessment of Educational Progress (NAEP) assessment provide the best current indicator for how well elementary students across the U.S. understand this, and other concepts. However, beyond expert reviews and statistical analysis,…

  2. General chemistry

    International Nuclear Information System (INIS)

    Kwon, Yeong Sik; Lee, Dong Seop; Ryu, Haung Ryong; Jang, Cheol Hyeon; Choi, Bong Jong; Choi, Sang Won

    1993-07-01

    The book concentrates on the latest general chemistry, which is divided int twenty-three chapters. It deals with basic conception and stoichiometry, nature of gas, structure of atoms, quantum mechanics, symbol and structure of an electron of ion and molecule, chemical thermodynamics, nature of solid, change of state and liquid, properties of solution, chemical equilibrium, solution and acid-base, equilibrium of aqueous solution, electrochemistry, chemical reaction speed, molecule spectroscopy, hydrogen, oxygen and water, metallic atom; 1A, IIA, IIIA, carbon and atom IVA, nonmetal atom and an inert gas, transition metals, lanthanons, and actinoids, nuclear properties and radioactivity, biochemistry and environment chemistry.

  3. Automated Scoring of Constructed-Response Science Items: Prospects and Obstacles

    Science.gov (United States)

    Liu, Ou Lydia; Brew, Chris; Blackmore, John; Gerard, Libby; Madhok, Jacquie; Linn, Marcia C.

    2014-01-01

    Content-based automated scoring has been applied in a variety of science domains. However, many prior applications involved simplified scoring rubrics without considering rubrics representing multiple levels of understanding. This study tested a concept-based scoring tool for content-based scoring, c-rater™, for four science items with rubrics…

  4. Measuring organizational effectiveness in information and communication technology companies using item response theory.

    Science.gov (United States)

    Trierweiller, Andréa Cristina; Peixe, Blênio César Severo; Tezza, Rafael; Pereira, Vera Lúcia Duarte do Valle; Pacheco, Waldemar; Bornia, Antonio Cezar; de Andrade, Dalton Francisco

    2012-01-01

    The aim of this paper is to measure the effectiveness of the organizations Information and Communication Technology (ICT) from the point of view of the manager, using Item Response Theory (IRT). There is a need to verify the effectiveness of these organizations which are normally associated to complex, dynamic, and competitive environments. In academic literature, there is disagreement surrounding the concept of organizational effectiveness and its measurement. A construct was elaborated based on dimensions of effectiveness towards the construction of the items of the questionnaire which submitted to specialists for evaluation. It demonstrated itself to be viable in measuring organizational effectiveness of ICT companies under the point of view of a manager through using Two-Parameter Logistic Model (2PLM) of the IRT. This modeling permits us to evaluate the quality and property of each item placed within a single scale: items and respondents, which is not possible when using other similar tools.

  5. An NCME Instructional Module on Polytomous Item Response Theory Models

    Science.gov (United States)

    Penfield, Randall David

    2014-01-01

    A polytomous item is one for which the responses are scored according to three or more categories. Given the increasing use of polytomous items in assessment practices, item response theory (IRT) models specialized for polytomous items are becoming increasingly common. The purpose of this ITEMS module is to provide an accessible overview of…

  6. Loglinear multidimensional IRT models for polytomously scired Items

    NARCIS (Netherlands)

    Kelderman, Henk

    1988-01-01

    A loglinear item response theory (IRT) model is proposed that relates polytomously scored item responses to a multidimensional latent space. Each item may have a different response function where each item response may be explained by one or more latent traits. Item response functions may follow a

  7. A strategy for optimizing item-pool management

    NARCIS (Netherlands)

    Ariel, A.; van der Linden, Willem J.; Veldkamp, Bernard P.

    2006-01-01

    Item-pool management requires a balancing act between the input of new items into the pool and the output of tests assembled from it. A strategy for optimizing item-pool management is presented that is based on the idea of a periodic update of an optimal blueprint for the item pool to tune item

  8. Multi-Robot Item Delivery and Foraging: Two Sides of a Coin

    Directory of Open Access Journals (Sweden)

    Somchaya Liemhetcharat

    2015-09-01

    Full Text Available Multi-robot foraging has been widely studied in the literature, and the general assumption is that the robots are simple, i.e., with limited processing and carrying capacity. We previously studied continuous foraging with slightly more capable robots, and in this article, we are interested in using similar robots for item delivery. Interestingly, item delivery and foraging are two sides of the same coin: foraging an item from a location is similar to satisfying a demand. We formally define the multi-robot item delivery problem and show that the continuous foraging problem is a special case of it. We contribute distributed multi-robot algorithms that solve the item delivery and foraging problems and describe how our shared world model is synchronized across the multi-robot team. We performed extensive experiments on simulated robots using a Java simulator, and we present our results to demonstrate that we outperform benchmark algorithms from multi-robot foraging.

  9. The Long-Term Conditions Questionnaire: conceptual framework and item development.

    Science.gov (United States)

    Peters, Michele; Potter, Caroline M; Kelly, Laura; Hunter, Cheryl; Gibbons, Elizabeth; Jenkinson, Crispin; Coulter, Angela; Forder, Julien; Towers, Ann-Marie; A'Court, Christine; Fitzpatrick, Ray

    2016-01-01

    To identify the main issues of importance when living with long-term conditions to refine a conceptual framework for informing the item development of a patient-reported outcome measure for long-term conditions. Semi-structured qualitative interviews (n=48) were conducted with people living with at least one long-term condition. Participants were recruited through primary care. The interviews were transcribed verbatim and analyzed by thematic analysis. The analysis served to refine the conceptual framework, based on reviews of the literature and stakeholder consultations, for developing candidate items for a new measure for long-term conditions. Three main organizing concepts were identified: impact of long-term conditions, experience of services and support, and self-care. The findings helped to refine a conceptual framework, leading to the development of 23 items that represent issues of importance in long-term conditions. The 23 candidate items formed the first draft of the measure, currently named the Long-Term Conditions Questionnaire. The aim of this study was to refine the conceptual framework and develop items for a patient-reported outcome measure for long-term conditions, including single and multiple morbidities and physical and mental health conditions. Qualitative interviews identified the key themes for assessing outcomes in long-term conditions, and these underpinned the development of the initial draft of the measure. These initial items will undergo cognitive testing to refine the items prior to further validation in a survey.

  10. A Quantum Chemistry Concept Inventory for Physical Chemistry Classes

    Science.gov (United States)

    Dick-Perez, Marilu; Luxford, Cynthia J.; Windus, Theresa L.; Holme, Thomas

    2016-01-01

    A 14-item, multiple-choice diagnostic assessment tool, the quantum chemistry concept inventory or QCCI, is presented. Items were developed based on published student misconceptions and content coverage and then piloted and used in advanced physical chemistry undergraduate courses. In addition to the instrument itself, data from both a pretest,…

  11. Basic concepts

    International Nuclear Information System (INIS)

    Dorner, B.

    1999-01-01

    The basic concepts of neutron scattering as a tool for studying the structure and the dynamics of condensed matter. Theoretical aspects are outlined, the two different cases of coherent and incoherent scattering are presented. The issue of resolution, coherence volume and the role of monochromators are also discussed. (K.A.)

  12. Simple Concepts

    Czech Academy of Sciences Publication Activity Database

    Materna, Pavel

    2013-01-01

    Roč. 28, č. 3 (2013), s. 295-319 ISSN 0353-5150 R&D Projects: GA ČR(CZ) GAP401/10/0792 Institutional support: RVO:67985955 Keywords : concept * constructions * set-theoretical paradigm Subject RIV: AA - Philosophy ; Religion

  13. Testing the generalized partial credit model

    NARCIS (Netherlands)

    Glas, Cornelis A.W.

    1996-01-01

    The partial credit model (PCM) (G.N. Masters, 1982) can be viewed as a generalization of the Rasch model for dichotomous items to the case of polytomous items. In many cases, the PCM is too restrictive to fit the data. Several generalizations of the PCM have been proposed. In this paper, a

  14. Counterfeit and Fraudulent Items - Mitigating the risk

    International Nuclear Information System (INIS)

    Tannenbaum, Marc

    2011-01-01

    This presentation (slides) provides an overview of the industry's challenges and activities. Firstly, it outlines the differences between counterfeit, fraudulent, suspect, and also substandard items. Notice is given that items could be found not to meet the standard, but the difference in the intent to deceive with counterfeit and fraudulent items is the critical element. Examples from other industries are used which also rely heavily on the assurance of quality for safety. It also informs that EPRI has just completed a report in October 2009 in coordination with other US government agencies and industry organizations; this report, entitled Counterfeit, Substandard and Fraudulent Items, number 1019163, is available for free on the EPRI web site. As a follow-up to this report, EPRI is developing a CFSI Database; any country interested in a collaborative agreement is invited to use and contribute to the database information. Finally, it stresses the importance of the oversight of contractors, training to raise the awareness of the employees and the inspectors, and having a response plan for identified items

  15. Parameter Optimization for Feature and Hit Generation in a General Unknown Screening Method-Proof of Concept Study Using a Design of Experiment Approach for a High Resolution Mass Spectrometry Procedure after Data Independent Acquisition.

    Science.gov (United States)

    Elmiger, Marco P; Poetzsch, Michael; Steuer, Andrea E; Kraemer, Thomas

    2018-03-06

    High resolution mass spectrometry and modern data independent acquisition (DIA) methods enable the creation of general unknown screening (GUS) procedures. However, even when DIA is used, its potential is far from being exploited, because often, the untargeted acquisition is followed by a targeted search. Applying an actual GUS (including untargeted screening) produces an immense amount of data that must be dealt with. An optimization of the parameters regulating the feature detection and hit generation algorithms of the data processing software could significantly reduce the amount of unnecessary data and thereby the workload. Design of experiment (DoE) approaches allow a simultaneous optimization of multiple parameters. In a first step, parameters are evaluated (crucial or noncrucial). Second, crucial parameters are optimized. The aim in this study was to reduce the number of hits, without missing analytes. The obtained parameter settings from the optimization were compared to the standard settings by analyzing a test set of blood samples spiked with 22 relevant analytes as well as 62 authentic forensic cases. The optimization lead to a marked reduction of workload (12.3 to 1.1% and 3.8 to 1.1% hits for the test set and the authentic cases, respectively) while simultaneously increasing the identification rate (68.2 to 86.4% and 68.8 to 88.1%, respectively). This proof of concept study emphasizes the great potential of DoE approaches to master the data overload resulting from modern data independent acquisition methods used for general unknown screening procedures by optimizing software parameters.

  16. A Chemistry Concept Reasoning Test

    Science.gov (United States)

    Cloonan, Carrie A.; Hutchinson, John S.

    2011-01-01

    A Chemistry Concept Reasoning Test was created and validated providing an easy-to-use tool for measuring conceptual understanding and critical scientific thinking of general chemistry models and theories. The test is designed to measure concept understanding comparable to that found in free-response questions requiring explanations over…

  17. Exploring differential item functioning (DIF) with the Rasch model: a comparison of gender differences on eighth grade science items in the United States and Spain.

    Science.gov (United States)

    Babiar, Tasha Calvert

    2011-01-01

    Traditionally, women and minorities have not been fully represented in science and engineering. Numerous studies have attributed these differences to gaps in science achievement as measured by various standardized tests. Rather than describe mean group differences in science achievement across multiple cultures, this study focused on an in-depth item-level analysis across two countries: Spain and the United States. This study investigated eighth-grade gender differences on science items across the two countries. A secondary purpose of the study was to explore the nature of gender differences using the many-faceted Rasch Model as a way to estimate gender DIF. A secondary analysis of data from the Third International Mathematics and Science Study (TIMSS) was used to address three questions: 1) Does gender DIF in science achievement exist? 2) Is there a relationship between gender DIF and characteristics of the science items? 3) Do the relationships between item characteristics and gender DIF in science items replicate across countries. Participants included 7,087 eight grade students from the United States and 3,855 students from Spain who participated in TIMSS. The Facets program (Linacre and Wright, 1992) was used to estimate gender DIF. The results of the analysis indicate that the content of the item seemed to be related to gender DIF. The analysis also suggests that there is a relationship between gender DIF and item format. No pattern of gender DIF related to cognitive demand was found. The general pattern of gender DIF was similar across the two countries used in the analysis. The strength of item-level analysis as opposed to group mean difference analysis is that gender differences can be detected at the item level, even when no mean differences can be detected at the group level.

  18. Nonsymmetric entropy I: basic concepts and results

    OpenAIRE

    Liu, Chengshi

    2006-01-01

    A new concept named nonsymmetric entropy which generalizes the concepts of Boltzman's entropy and shannon's entropy, was introduced. Maximal nonsymmetric entropy principle was proven. Some important distribution laws were derived naturally from maximal nonsymmetric entropy principle.

  19. Verification of Differential Item Functioning (DIF) Status of West ...

    African Journals Online (AJOL)

    This study investigated test item bias and Differential Item Functioning (DIF) of West African ... items in chemistry function differentially with respect to gender and location. In Aba education zone of Abia, 50 secondary schools were purposively ...

  20. University Students Alternative Conceptions On Circular Motion

    OpenAIRE

    Ian Phil Canlas

    2015-01-01

    This study attempted to find out university students alternative conceptions on circular motion. An 18-item researcher-compiled and content-validated questionnaire was administered to twenty-six 26 students taking up a program in Bachelor in Secondary Education-Physical Science in their second year enrolled in a course on mechanics. Results revealed that majority of the students possess alternative conceptions on circular motion specifically along velocity acceleration and force. Moreover res...

  1. Development and validation of 26-item dysfunctional attitude scale.

    Science.gov (United States)

    Ebrahimi, Amrollah; Samouei, Rahele; Mousavii, Sayyed Ghafour; Bornamanesh, Ali Reza

    2013-06-01

    Dysfunctional Attitude Scale is one of the most common instruments used to assess cognitive vulnerability. This study aimed to develop and validate a short form of Dysfunctional Attitude Scale appropriate for an Iranian clinical population. Participants were 160 psychiatric patients from medical centers affiliated with Isfahan Medical University, as well as 160 non-patients. Research instruments were clinical interviews based on the Diagnostic and Statistical Manual-IV-TR, Dysfunctional Attitude Scale and General Heath Questionnaire (GHQ-28). Data was analyzed using multicorrelation calculations and factor analysis. Based on the results of factor analysis and item-total correlation, 14 items were judged candidates for omission. Analysis of the 26-item Dysfunctional Attitude Scale (DAS-26) revealed a Cronbach's alpha of 0.92. Evidence for the concurrent criterion validity was obtained through calculating the correlation between the Dysfunctional Attitude Scale and psychiatric diagnosis (r = 0.55), GHQ -28 (r = 0.56) and somatization, anxiety, social dysfunction, and depression subscales (0.45,0.53,0.48, and 0.57, respectively). Factor analysis deemed a four-factor structure the best. The factors were labeled as success-perfectionism, need for approval, need for satisfying others, and vulnerability-performance evaluation. The results showed that the Iranian version of the Dysfunctional Attitude Scale (DAS-26) bears satisfactory psychometric properties suggesting that this cognitive instrument is appropriate for use in an Iranian cultural context. Copyright © 2012 Wiley Publishing Asia Pty Ltd.

  2. Seeking missing pieces in science concept assessments: Reevaluating the Brief Electricity and Magnetism Assessment through Rasch analysis

    Science.gov (United States)

    Ding, Lin

    2014-02-01

    Discipline-based science concept assessments are powerful tools to measure learners' disciplinary core ideas. Among many such assessments, the Brief Electricity and Magnetism Assessment (BEMA) has been broadly used to gauge student conceptions of key electricity and magnetism (E&M) topics in college-level introductory physics courses. Differing from typical concept inventories that focus only on one topic of a subject area, BEMA covers a broad range of topics in the electromagnetism domain. In spite of this fact, prior studies exclusively used a single aggregate score to represent individual students' overall understanding of E&M without explicating the construct of this assessment. Additionally, BEMA has been used to compare traditional physics courses with a reformed course entitled Matter and Interactions (M&I). While prior findings were in favor of M&I, no empirical evidence was sought to rule out possible differential functioning of BEMA that may have inadvertently advantaged M&I students. In this study, we used Rasch analysis to seek two missing pieces regarding the construct and differential functioning of BEMA. Results suggest that although BEMA items generally can function together to measure the same construct of application and analysis of E&M concepts, several items may need further revision. Additionally, items that demonstrate differential functioning for the two courses are detected. Issues such as item contextual features and student familiarity with question settings may underlie these findings. This study highlights often overlooked threats in science concept assessments and provides an exemplar for using evidence-based reasoning to make valid inferences and arguments.

  3. Seeking missing pieces in science concept assessments: Reevaluating the Brief Electricity and Magnetism Assessment through Rasch analysis

    Directory of Open Access Journals (Sweden)

    Lin Ding

    2014-02-01

    Full Text Available Discipline-based science concept assessments are powerful tools to measure learners’ disciplinary core ideas. Among many such assessments, the Brief Electricity and Magnetism Assessment (BEMA has been broadly used to gauge student conceptions of key electricity and magnetism (E&M topics in college-level introductory physics courses. Differing from typical concept inventories that focus only on one topic of a subject area, BEMA covers a broad range of topics in the electromagnetism domain. In spite of this fact, prior studies exclusively used a single aggregate score to represent individual students’ overall understanding of E&M without explicating the construct of this assessment. Additionally, BEMA has been used to compare traditional physics courses with a reformed course entitled Matter and Interactions (M&I. While prior findings were in favor of M&I, no empirical evidence was sought to rule out possible differential functioning of BEMA that may have inadvertently advantaged M&I students. In this study, we used Rasch analysis to seek two missing pieces regarding the construct and differential functioning of BEMA. Results suggest that although BEMA items generally can function together to measure the same construct of application and analysis of E&M concepts, several items may need further revision. Additionally, items that demonstrate differential functioning for the two courses are detected. Issues such as item contextual features and student familiarity with question settings may underlie these findings. This study highlights often overlooked threats in science concept assessments and provides an exemplar for using evidence-based reasoning to make valid inferences and arguments.

  4. Conjunctive and Disjunctive Item Response Functions.

    Science.gov (United States)

    1984-10-01

    fed set ofvaluesof a, b, AI , B1 A2 2 . 2 A3 , and 13 , the f ’. g ’a. nd h’a in (7) are fied. Equation (7) must still hold for S - e19029e3,..* . Thus...for Item I Is -- b ?(a:1 , b1 ,O) (1 + ’)(I + e4 (22 where a and pi are arbitrary constants. These constants mst be the sam for all Items In a given...NETHERLIS I E3I1 Focility-Acquisitions 4133 Rugby Avnue 1 Lee Cronbach Bethesda, NO 20014 16 Laburnue Road Atherton, CA 94205 1 Dr. Benjamin A. Fairbank

  5. Astrophysical Concepts

    CERN Document Server

    Harwit, Martin

    2006-01-01

    This classic text, aimed at senior undergraduates and beginning graduate students in physics and astronomy, presents a wide range of astrophysical concepts in sufficient depth to give the reader a quantitative understanding of the subject. Emphasizing physical concepts, the book outlines cosmic events but does not portray them in detail: it provides a series of astrophysical sketches. For this fourth edition, nearly every part of the text has been reconsidered and rewritten, new sections have been added to cover recent developments, and others have been extensively revised and brought up to date. The book begins with an outline of the scope of modern astrophysics and enumerates some of the outstanding problems faced in the field today. The basic physics needed to tackle these questions are developed in the next few chapters using specific astronomical processes as examples. The second half of the book enlarges on these topics and shows how we can obtain quantitative insight into the structure and evolution of...

  6. Introductory concepts

    International Nuclear Information System (INIS)

    Barnes, W.E.

    1983-01-01

    Physical theories are commonly classified as being either ''classical'' or ''modern''. The reasons for this distinction are both historical and substantive. Limited in the sophistication of their measuring instruments, early scientists proposed theories appropriate for the description of the simplest and most accessible physical phenomena, e.g., the trajectories of the planets. Because of the class of phenomena observed, certain beliefs came to underlie all classical theories with regard to the nature of time, space, matter, etc. For example, the idea was undisputed that an object has at all times both a definite position and velocity. Not until the interior of the atom and the nature of electromagnetic radiation were explored was it discovered that the concepts of classical physics are inadequate to deal with many phenomena. A reassessment of fundamental postulates led to the formulation of modern physics which, it is believed, successfully treats the behavior of all physical systems. To gain an understanding of the rudiments of modern physics, one proceeds as the early scientists did by first mastering the classical concepts that emerge from their intuitive picture of the world. Modifications of these concepts are subsequently introduced which allow a more accurate treatment of physical phenomena, particularly atomic and nuclear systems

  7. A Comparison of the 27-Item and 12-Item Intolerance of Uncertainty Scales

    Science.gov (United States)

    Khawaja, Nigar G.; Yu, Lai Ngo Heidi

    2010-01-01

    The 27-item Intolerance of Uncertainty Scale (IUS) has become one of the most frequently used measures of Intolerance of Uncertainty. More recently, an abridged, 12-item version of the IUS has been developed. The current research used clinical (n = 50) and non-clinical (n = 56) samples to examine and compare the psychometric properties of both…

  8. Modeling Local Item Dependence in Cloze and Reading Comprehension Test Items Using Testlet Response Theory

    Science.gov (United States)

    Baghaei, Purya; Ravand, Hamdollah

    2016-01-01

    In this study the magnitudes of local dependence generated by cloze test items and reading comprehension items were compared and their impact on parameter estimates and test precision was investigated. An advanced English as a foreign language reading comprehension test containing three reading passages and a cloze test was analyzed with a…

  9. The hue of concepts.

    Science.gov (United States)

    Albertazzi, Liliana; Canal, Luisa; Malfatti, Michela; Micciolo, Rocco

    2013-01-01

    The study shows a systematic naturally biased association between percepts and concepts. Specifically, it shows that a series of terms pertaining to an abstract semantic field (related to the frame of ethics in social behaviour) has a nonrandom, highly significant, association with colours (hues). This is the first time that consistent associations between abstract terms and colours have been reported in the general population. The main hypothesis, ie that there appear to be 'hues of concepts', was borne out by the results: the abstract terms considered were coloured with blue/green (ie cool) colours as well as their synonyms, while their antonyms were coloured with red/yellow (ie warm) colours. The association provides information about the nature of abstract concepts and their relationship with perception. It also sheds light on the interrelations among words in semantic domains that, to date, have been studied from only a computational viewpoint.

  10. Why Japanese workers show low work engagement: An item response theory analysis of the Utrecht Work Engagement scale.

    Science.gov (United States)

    Shimazu, Akihito; Schaufeli, Wilmar B; Miyanaka, Daisuke; Iwata, Noboru

    2010-11-05

    With the globalization of occupational health psychology, more and more researchers are interested in applying employee well-being like work engagement (i.e., a positive, fulfilling, work-related state of mind that is characterized by vigor, dedication, and absorption) to diverse populations. Accurate measurement contributes to our further understanding and to the generalizability of the concept of work engagement across different cultures. The present study investigated the measurement accuracy of the Japanese and the original Dutch versions of the Utrecht Work Engagement Scale (9-item version, UWES-9) and the comparability of this scale between both countries. Item Response Theory (IRT) was applied to the data from Japan (N = 2,339) and the Netherlands (N = 13,406). Reliability of the scale was evaluated at various levels of the latent trait (i.e., work engagement) based the test information function (TIF) and the standard error of measurement (SEM). The Japanese version had difficulty in differentiating respondents with extremely low work engagement, whereas the original Dutch version had difficulty in differentiating respondents with high work engagement. The measurement accuracy of both versions was not similar. Suppression of positive affect among Japanese people and self-enhancement (the general sensitivity to positive self-relevant information) among Dutch people may have caused decreased measurement accuracy. Hence, we should be cautious when interpreting low engagement scores among Japanese as well as high engagement scores among western employees.

  11. Why Japanese workers show low work engagement: An item response theory analysis of the Utrecht Work Engagement scale

    Directory of Open Access Journals (Sweden)

    Iwata Noboru

    2010-11-01

    Full Text Available Abstract With the globalization of occupational health psychology, more and more researchers are interested in applying employee well-being like work engagement (i.e., a positive, fulfilling, work-related state of mind that is characterized by vigor, dedication, and absorption to diverse populations. Accurate measurement contributes to our further understanding and to the generalizability of the concept of work engagement across different cultures. The present study investigated the measurement accuracy of the Japanese and the original Dutch versions of the Utrecht Work Engagement Scale (9-item version, UWES-9 and the comparability of this scale between both countries. Item Response Theory (IRT was applied to the data from Japan (N = 2,339 and the Netherlands (N = 13,406. Reliability of the scale was evaluated at various levels of the latent trait (i.e., work engagement based the test information function (TIF and the standard error of measurement (SEM. The Japanese version had difficulty in differentiating respondents with extremely low work engagement, whereas the original Dutch version had difficulty in differentiating respondents with high work engagement. The measurement accuracy of both versions was not similar. Suppression of positive affect among Japanese people and self-enhancement (the general sensitivity to positive self-relevant information among Dutch people may have caused decreased measurement accuracy. Hence, we should be cautious when interpreting low engagement scores among Japanese as well as high engagement scores among western employees.

  12. Adult Attachment Ratings (AAR): an item response theory analysis.

    Science.gov (United States)

    Pilkonis, Paul A; Kim, Yookyung; Yu, Lan; Morse, Jennifer Q

    2014-01-01

    The Adult Attachment Ratings (AAR) include 3 scales for anxious, ambivalent attachment (excessive dependency, interpersonal ambivalence, and compulsive care-giving), 3 for avoidant attachment (rigid self-control, defensive separation, and emotional detachment), and 1 for secure attachment. The scales include items (ranging from 6-16 in their original form) scored by raters using a 3-point format (0 = absent, 1 = present, and 2 = strongly present) and summed to produce a total score. Item response theory (IRT) analyses were conducted with data from 414 participants recruited from psychiatric outpatient, medical, and community settings to identify the most informative items from each scale. The IRT results allowed us to shorten the scales to 5-item versions that are more precise and easier to rate because of their brevity. In general, the effective range of measurement for the scales was 0 to +2 SDs for each of the attachment constructs; that is, from average to high levels of attachment problems. Evidence for convergent and discriminant validity of the scales was investigated by comparing them with the Experiences of Close Relationships-Revised (ECR-R) scale and the Kobak Attachment Q-sort. The best consensus among self-reports on the ECR-R, informant ratings on the ECR-R, and expert judgments on the Q-sort and the AAR emerged for anxious, ambivalent attachment. Given the good psychometric characteristics of the scale for secure attachment, however, this measure alone might provide a simple alternative to more elaborate procedures for some measurement purposes. Conversion tables are provided for the 7 scales to facilitate transformation from raw scores to IRT-calibrated (theta) scores.

  13. A general framework for intelligent recommender systems

    Directory of Open Access Journals (Sweden)

    Jose Aguilar

    2017-07-01

    Full Text Available In this paper, we propose a general framework for an intelligent recommender system that extends the concept of a knowledge-based recommender system. The intelligent recommender system exploits knowledge, learns, discovers new information, infers preferences and criticisms, among other things. For that, the framework of an intelligent recommender system is defined by the following components: knowledge representation paradigm, learning methods, and reasoning mechanisms. Additionally, it has five knowledge models about the different aspects that we can consider during a recommendation: users, items, domain, context and criticisms. The mix of the components exploits the knowledge, updates it and infers, among other things. In this work, we implement one intelligent recommender system based on this framework, using Fuzzy Cognitive Maps (FCMs. Next, we test the performance of the intelligent recommender system with specialized criteria linked to the utilization of the knowledge in order to test the versatility and performance of the framework.

  14. An emotional functioning item bank of 24 items for computerized adaptive testing (CAT) was established

    DEFF Research Database (Denmark)

    Petersen, Morten Aa.; Gamper, Eva-Maria; Costantini, Anna

    2016-01-01

    of the widely used EORTC Quality of Life questionnaire (QLQ-C30). STUDY DESIGN AND SETTING: On the basis of literature search and evaluations by international samples of experts and cancer patients, 38 candidate items were developed. The psychometric properties of the items were evaluated in a large...... international sample of cancer patients. This included evaluations of dimensionality, item response theory (IRT) model fit, differential item functioning (DIF), and of measurement precision/statistical power. RESULTS: Responses were obtained from 1,023 cancer patients from four countries. The evaluations showed...... that 24 items could be included in a unidimensional IRT model. DIF did not seem to have any significant impact on the estimation of EF. Evaluations indicated that the CAT measure may reduce sample size requirements by up to 50% compared to the QLQ-C30 EF scale without reducing power. CONCLUSION...

  15. Differential item functioning magnitude and impact measures from item response theory models.

    Science.gov (United States)

    Kleinman, Marjorie; Teresi, Jeanne A

    2016-01-01

    Measures of magnitude and impact of differential item functioning (DIF) at the item and scale level, respectively are presented and reviewed in this paper. Most measures are based on item response theory models. Magnitude refers to item level effect sizes, whereas impact refers to differences between groups at the scale score level. Reviewed are magnitude measures based on group differences in the expected item scores and impact measures based on differences in the expected scale scores. The similarities among these indices are demonstrated. Various software packages are described that provide magnitude and impact measures, and new software presented that computes all of the available statistics conveniently in one program with explanations of their relationships to one another.

  16. The PROMIS Physical Function item bank was calibrated to a standardized metric and shown to improve measurement efficiency.

    Science.gov (United States)

    Rose, Matthias; Bjorner, Jakob B; Gandek, Barbara; Bruce, Bonnie; Fries, James F; Ware, John E

    2014-05-01

    To document the development and psychometric evaluation of the Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function (PF) item bank and static instruments. The items were evaluated using qualitative and quantitative methods. A total of 16,065 adults answered item subsets (n>2,200/item) on the Internet, with oversampling of the chronically ill. Classical test and item response theory methods were used to evaluate 149 PROMIS PF items plus 10 Short Form-36 and 20 Health Assessment Questionnaire-Disability Index items. A graded response model was used to estimate item parameters, which were normed to a mean of 50 (standard deviation [SD]=10) in a US general population sample. The final bank consists of 124 PROMIS items covering upper, central, and lower extremity functions and instrumental activities of daily living. In simulations, a 10-item computerized adaptive test (CAT) eliminated floor and decreased ceiling effects, achieving higher measurement precision than any comparable length static tool across four SDs of the measurement range. Improved psychometric properties were transferred to the CAT's superior ability to identify differences between age and disease groups. The item bank provides a common metric and can improve the measurement of PF by facilitating the standardization of patient-reported outcome measures and implementation of CATs for more efficient PF assessments over a larger range. Copyright © 2014. Published by Elsevier Inc.

  17. Applying modern psychometric techniques to melodic discrimination testing: Item response theory, computerised adaptive testing, and automatic item generation.

    Science.gov (United States)

    Harrison, Peter M C; Collins, Tom; Müllensiefen, Daniel

    2017-06-15

    Modern psychometric theory provides many useful tools for ability testing, such as item response theory, computerised adaptive testing, and automatic item generation. However, these techniques have yet to be integrated into mainstream psychological practice. This is unfortunate, because modern psychometric techniques can bring many benefits, including sophisticated reliability measures, improved construct validity, avoidance of exposure effects, and improved efficiency. In the present research we therefore use these techniques to develop a new test of a well-studied psychological capacity: melodic discrimination, the ability to detect differences between melodies. We calibrate and validate this test in a series of studies. Studies 1 and 2 respectively calibrate and validate an initial test version, while Studies 3 and 4 calibrate and validate an updated test version incorporating additional easy items. The results support the new test's viability, with evidence for strong reliability and construct validity. We discuss how these modern psychometric techniques may also be profitably applied to other areas of music psychology and psychological science in general.

  18. Maternal sensitivity: a concept analysis.

    Science.gov (United States)

    Shin, Hyunjeong; Park, Young-Joo; Ryu, Hosihn; Seomun, Gyeong-Ae

    2008-11-01

    The aim of this paper is to report a concept analysis of maternal sensitivity. Maternal sensitivity is a broad concept encompassing a variety of interrelated affective and behavioural caregiving attributes. It is used interchangeably with the terms maternal responsiveness or maternal competency, with no consistency of use. There is a need to clarify the concept of maternal sensitivity for research and practice. A search was performed on the CINAHL and Ovid MEDLINE databases using 'maternal sensitivity', 'maternal responsiveness' and 'sensitive mothering' as key words. The searches yielded 54 records for the years 1981-2007. Rodgers' method of evolutionary concept analysis was used to analyse the material. Four critical attributes of maternal sensitivity were identified: (a) dynamic process involving maternal abilities; (b) reciprocal give-and-take with the infant; (c) contingency on the infant's behaviour and (d) quality of maternal behaviours. Maternal identity and infant's needs and cues are antecedents for these attributes. The consequences are infant's comfort, mother-infant attachment and infant development. In addition, three positive affecting factors (social support, maternal-foetal attachment and high self-esteem) and three negative affecting factors (maternal depression, maternal stress and maternal anxiety) were identified. A clear understanding of the concept of maternal sensitivity could be useful for developing ways to enhance maternal sensitivity and to maximize the developmental potential of infants. Knowledge of the attributes of maternal sensitivity identified in this concept analysis may be helpful for constructing measuring items or dimensions.

  19. 47 CFR 32.7600 - Extraordinary items.

    Science.gov (United States)

    2010-10-01

    ... FOR TELECOMMUNICATIONS COMPANIES Instructions For Other Income Accounts § 32.7600 Extraordinary items... extraordinary. Extraordinary events and transactions are distinguished by both their unusual nature and by the infrequency of their occurrence, taking into account the environment in which the company operates. This...

  20. Soviet Cybernetics: Recent News Items, Number Thirteen.

    Science.gov (United States)

    Holland, Wade B.

    An issue of "Soviet Cybernetics: Recent News Items" consists of English translations of the leading recent Soviet contributions to the study of cybernetics. Articles deal with cybernetics in the 21st Century; the Soviet State Committee on Science and Technology; economic reforms in Rudnev's ministry; an interview with Rudnev; Dnepr-2; Dnepr-2…

  1. Random Item Generation Is Affected by Age

    Science.gov (United States)

    Multani, Namita; Rudzicz, Frank; Wong, Wing Yiu Stephanie; Namasivayam, Aravind Kumar; van Lieshout, Pascal

    2016-01-01

    Purpose: Random item generation (RIG) involves central executive functioning. Measuring aspects of random sequences can therefore provide a simple method to complement other tools for cognitive assessment. We examine the extent to which RIG relates to specific measures of cognitive function, and whether those measures can be estimated using RIG…

  2. In-Process Items on LCS.

    Science.gov (United States)

    Russell, Thyra K.

    Morris Library at Southern Illinois University computerized its technical processes using the Library Computer System (LCS), which was implemented in the library to streamline order processing by: (1) providing up-to-date online files to track in-process items; (2) encouraging quick, efficient accessing of information; (3) reducing manual files;…

  3. Algorithmic test design using classical item parameters

    NARCIS (Netherlands)

    van der Linden, Willem J.; Adema, Jos J.

    Two optimalization models for the construction of tests with a maximal value of coefficient alpha are given. Both models have a linear form and can be solved by using a branch-and-bound algorithm. The first model assumes an item bank calibrated under the Rasch model and can be used, for instance,

  4. Item Effects in Recognition Memory for Words

    Science.gov (United States)

    Freeman, Emily; Heathcote, Andrew; Chalmers, Kerry; Hockley, William

    2010-01-01

    We investigate the effects of word characteristics on episodic recognition memory using analyses that avoid Clark's (1973) "language-as-a-fixed-effect" fallacy. Our results demonstrate the importance of modeling word variability and show that episodic memory for words is strongly affected by item noise (Criss & Shiffrin, 2004), as measured by the…

  5. Extending Item Response Theory to Online Homework

    Science.gov (United States)

    Kortemeyer, Gerd

    2014-01-01

    Item response theory (IRT) becomes an increasingly important tool when analyzing "big data" gathered from online educational venues. However, the mechanism was originally developed in traditional exam settings, and several of its assumptions are infringed upon when deployed in the online realm. For a large-enrollment physics course for…

  6. Item Response Theory for Peer Assessment

    Science.gov (United States)

    Uto, Masaki; Ueno, Maomi

    2016-01-01

    As an assessment method based on a constructivist approach, peer assessment has become popular in recent years. However, in peer assessment, a problem remains that reliability depends on the rater characteristics. For this reason, some item response models that incorporate rater parameters have been proposed. Those models are expected to improve…

  7. 77 FR 59339 - Acquisition of Commercial Items

    Science.gov (United States)

    2012-09-27

    ... DEPARTMENT OF DEFENSE Defense Acquisition Regulations System 48 CFR Part 212 Acquisition of Commercial Items CFR Correction 212.504 [Corrected] In Title 48 of the Code of Federal Regulations, Chapter 2 (Parts 201--299), revised as of October 1, 2011, on page 73, in section 212.504, paragraph (a) is...

  8. Bayesian item selection criteria for adaptive testing

    NARCIS (Netherlands)

    van der Linden, Willem J.

    1996-01-01

    R.J. Owen (1975) proposed an approximate empirical Bayes procedure for item selection in adaptive testing. The procedure replaces the true posterior by a normal approximation with closed-form expressions for its first two moments. This approximation was necessary to minimize the computational

  9. Aging and Confidence Judgments in Item Recognition

    Science.gov (United States)

    Voskuilen, Chelsea; Ratcliff, Roger; McKoon, Gail

    2018-01-01

    We examined the effects of aging on performance in an item-recognition experiment with confidence judgments. A model for confidence judgments and response time (RTs; Ratcliff & Starns, 2013) was used to fit a large amount of data from a new sample of older adults and a previously reported sample of younger adults. This model of confidence…

  10. 10 CFR 74.55 - Item monitoring.

    Science.gov (United States)

    2010-01-01

    ... Quantities of Strategic Special Nuclear Material § 74.55 Item monitoring. (a) Licensees subject to § 74.51... quantitatively measured, the validity of that measurement independently confirmed, and that additionally have..., except for reactor components measuring at least one meter in length and weighing in excess of 30...

  11. Identify, Organize, and Retrieve Items Using Zotero

    Science.gov (United States)

    Clark, Brian; Stierman, John

    2009-01-01

    Librarians build collections. To do this they use tools that help them identify, organize, and retrieve items for the collection. Zotero (zoh-TAIR-oh) is such a tool that helps the user build a library of useful books, articles, web sites, blogs, etc., discovered while surfing online. A visit to Zotero's homepage, www.zotero.org, shows a number of…

  12. Borrowing and Loan Words: The Lemmatizing of Newly Acquired Lexical Items in Sesotho sa Leboa

    Directory of Open Access Journals (Sweden)

    V.M. Mojela

    2011-10-01

    Full Text Available

    ABSTRACT: The influence of foreign languages in Sesotho sa Leboa, or Northern Sotho, results in borrowing, which ultimately leads to an increase in the vocabulary of Sesotho sa Leboa. The languages influencing developments in the vocabulary of Sesotho sa Leboa include, inter alia, English, Afrikaans, Xitsonga, Tshivend√a and the Nguni languages. This article aims to give a critical analysis of the advantages and disadvantages of the adoption of foreign lexical items in the lemmatization of vocabulary in Sesotho sa Leboa dictionaries. Most puristic inclined academics and intellectuals are reluctant to adopt loan words as a means of developing the Sesotho sa Leboa vocabulary. When confronted with borrowing, the purists usually prefer coinage, using indigenous lexical items to name foreign concepts. This is disadvantageous to the development of the vocabulary of the language because (1 there is no increase in the number of the lexical items in the language since only the meanings of the foreign lexical item are added to existing indigenous lexical items, and (2 in most cases, previously adopted loan words are mistaken for indigenous lexical items and given preference to newly acquired lexical items which have direct and accurate bearing on the meaning of the newly discovered or designed concepts or objects.

    OPSOMMING: Ontlening en leenwoorde: Die lemmatisering van nuutverworwe leksikale items in Sesotho sa Leboa. Die invloed van vreemde tale op Sesotho sa Leboa, of Noord-Sotho, het ontlening tot gevolg, wat uiteindelik lei tot 'n toename in die woordeskat van Sesotho sa Leboa. Die tale wat ontwikkelinge in die woordeskat van Sesotho sa Leboa beïnvloed, sluit onder andere Engels, Afrikaans, Xitsonga, Tsivend√a en die Ngunitale in. Die doel van hierdie artikel is om 'n kritiese ontleding van die voordele en nadele van die oorneem van vreemde leksikale items by die lemmatisering van die woordeskat in woordeboeke van Sesotho sa Leboa te

  13. Report to the Director General on the forty-fifth series of SAGSI meetings

    International Nuclear Information System (INIS)

    1997-11-01

    Mr. Graham Andrew chaired the 45th Series of SAGSI Meetings. Seventeen members of SAGSI attended the meeting, which was held in Vienna from 10 to 14 November 1997. The Secretariat was represented by Mr. R. Hooper, Director of the Division of Concepts and Planning, and other senior staff. SAGSI addressed the items on the agenda approved by the Director General, considered its work programme for the next period, and recommended an agenda for the next SAGSI meeting. This report to the Director General was prepared using drafting groups and was approved in plenary

  14. Creating the Chemistry in Cellular Respiration Concept Inventory (CCRCI)

    Science.gov (United States)

    Forshee, Jay Lance, II

    Students at our institution report cellular respiration to be the most difficult concept they encounter in undergraduate biology, but why students find this difficult is unknown. Students may find cellular respiration difficult because there is a large amount of steps, or because there are persistent, long-lasting misconceptions and misunderstandings surrounding their knowledge of chemistry, which affect their performance on cellular respiration assessments. Most studies of cellular respiration focus on student macro understanding of the process related to breathing, and matter and energy. To date, no studies identify which chemistry concepts are most relevant to students' development of an understanding of the process of cellular respiration or have developed an assessment to measure student understanding of them. Following the Delphi method, the researchers conducted expert interviews with faculty members from four-year, masters-, and PhD-granting institutions who teach undergraduate general biology, and are experts in their respective fields of biology. From these interviews, researchers identified twelve chemistry concepts important to understanding cellular respiration and using surveys, these twelve concepts were refined into five (electron transfer, energy transfer, thermodynamics (law/conservation), chemical reactions, and gradients). The researchers then interviewed undergraduate introductory biology students at a large Midwestern university to identify their knowledge and misconceptions of the chemistry concepts that the faculty had identified previously as important. The CCRCI was developed using the five important chemistry concepts underlying cellular respiration. The final version of the CCRCI was administered to n=160 introductory biology students during the spring 2017 semester. Reliability of the CCRCI was evaluated using Cronbach's alpha (=.7) and split-half reliability (=.769), and validity of the instrument was assessed through content validity

  15. Using Patient Health Questionnaire-9 item parameters of a common metric resulted in similar depression scores compared to independent item response theory model reestimation.

    Science.gov (United States)

    Liegl, Gregor; Wahl, Inka; Berghöfer, Anne; Nolte, Sandra; Pieh, Christoph; Rose, Matthias; Fischer, Felix

    2016-03-01

    To investigate the validity of a common depression metric in independent samples. We applied a common metrics approach based on item-response theory for measuring depression to four German-speaking samples that completed the Patient Health Questionnaire (PHQ-9). We compared the PHQ item parameters reported for this common metric to reestimated item parameters that derived from fitting a generalized partial credit model solely to the PHQ-9 items. We calibrated the new model on the same scale as the common metric using two approaches (estimation with shifted prior and Stocking-Lord linking). By fitting a mixed-effects model and using Bland-Altman plots, we investigated the agreement between latent depression scores resulting from the different estimation models. We found different item parameters across samples and estimation methods. Although differences in latent depression scores between different estimation methods were statistically significant, these were clinically irrelevant. Our findings provide evidence that it is possible to estimate latent depression scores by using the item parameters from a common metric instead of reestimating and linking a model. The use of common metric parameters is simple, for example, using a Web application (http://www.common-metrics.org) and offers a long-term perspective to improve the comparability of patient-reported outcome measures. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. A Multidimensional Partial Credit Model with Associated Item and Test Statistics: An Application to Mixed-Format Tests

    Science.gov (United States)

    Yao, Lihua; Schwarz, Richard D.

    2006-01-01

    Multidimensional item response theory (IRT) models have been proposed for better understanding the dimensional structure of data or to define diagnostic profiles of student learning. A compensatory multidimensional two-parameter partial credit model (M-2PPC) for constructed-response items is presented that is a generalization of those proposed to…

  17. The Influence of Task Demands, Verbal Ability and Executive Functions on Item and Source Memory in Autism Spectrum Disorder

    Science.gov (United States)

    Semino, Sara; Ring, Melanie; Bowler, Dermot M.; Gaigg, Sebastian B.

    2018-01-01

    Autism Spectrum Disorder (ASD) is generally associated with difficulties in contextual source memory but not single item memory. There are surprising inconsistencies in the literature, however, that the current study seeks to address by examining item and source memory in age and ability matched groups of 22 ASD and 21 comparison adults. Results…

  18. Why are the Mathematics National Examination Items Difficult and What Is Teachers’ Strategy to Overcome It?

    Directory of Open Access Journals (Sweden)

    Heri Retnawati

    2017-07-01

    Full Text Available The quality of national examination items plays an enormous role in identifying students’ competencies mastery and their difficulties. This study aims to identify the difficult items in the Junior High School Mathematics National Examination, to find the factors that cause students’ difficulty and to reveal the strategies that the teachers and the students might implement in order to overcome them. The study is phenomenological research with the mixed methods. The data were collected using documentation of students’ responses and focus group discussion (FGD of teachers. The data analysis was conducted using Milles & Hubberman steps. The results of the study showed that there were 4 difficult items of the 40 test items for the students. The students’ difficulties were the lack of concept understanding, difficulties in calculating, difficulties in selecting information, being deceived by the distractors, being unaccustomed to completing complex and non-integers test items, and completing contextual test items that have been presented in the form of figures or narrative texts.

  19. Exploring differential item functioning (DIF) with the Rasch model: A comparison of gender differences on eighth-grade science items in the United States and Spain

    Science.gov (United States)

    Calvert, Tasha

    Despite the attention that has been given to gender and science, boys continue to outperform girls in science achievement, particularly by the end of secondary school. Because it is unclear whether gender differences have narrowed over time (Leder, 1992; Willingham & Cole, 1997), it is important to continue a line of inquiry into the nature of gender differences, specifically at the international level. The purpose of this study was to investigate gender differences in science achievement across two countries: United States and Spain. A secondary purpose was to demonstrate an alternative method for exploring gender differences based on the many-faceted Rasch model (1980). A secondary analysis of the data from the Third International Mathematics and Science Study (TIMSS) was used to examine the relationship between gender DIF (differential item functioning) and item characteristics (item type, content, and performance expectation) across both countries. Nationally representative samples of eighth grade students in the United States and Spain who participated in TIMSS were analyzed to answer the research questions in this study. In both countries, girls showed an advantage over boys on life science items and most extended response items, whereas boys, by and large, had an advantage on earth science, physics, and chemistry items. However, even within areas that favored boys, such as physics, there were items that were differentially easier for girls. In general, patterns in gender differences were similar across both countries although there were a few differences between the countries on individual items. It was concluded that simply looking at mean differences does not provide an adequate understanding of the nature of gender differences in science achievement.

  20. Generalized polygons

    CERN Document Server

    Maldeghem, Hendrik

    1998-01-01

    This book is intended to be an introduction to the fascinating theory ofgeneralized polygons for both the graduate student and the specialized researcher in the field. It gathers together a lot of basic properties (some of which are usually referred to in research papers as belonging to folklore) and very recent and sometimes deep results. I have chosen a fairly strict geometrical approach, which requires some knowledge of basic projective geometry. Yet, it enables one to prove some typically group-theoretical results such as the determination of the automorphism groups of certain Moufang polygons. As such, some basic group-theoretical knowledge is required of the reader. The notion of a generalized polygon is a relatively recent one. But it is one of the most important concepts in incidence geometry. Generalized polygons are the building bricks of Tits buildings. They are the prototypes and precursors of more general geometries such as partial geometries, partial quadrangles, semi-partial ge­ ometries, near...

  1. Calibration of Automatically Generated Items Using Bayesian Hierarchical Modeling.

    Science.gov (United States)

    Johnson, Matthew S.; Sinharay, Sandip

    For complex educational assessments, there is an increasing use of "item families," which are groups of related items. However, calibration or scoring for such an assessment requires fitting models that take into account the dependence structure inherent among the items that belong to the same item family. C. Glas and W. van der Linden…

  2. Applying Hierarchical Model Calibration to Automatically Generated Items.

    Science.gov (United States)

    Williamson, David M.; Johnson, Matthew S.; Sinharay, Sandip; Bejar, Isaac I.

    This study explored the application of hierarchical model calibration as a means of reducing, if not eliminating, the need for pretesting of automatically generated items from a common item model prior to operational use. Ultimately the successful development of automatic item generation (AIG) systems capable of producing items with highly similar…

  3. 10 CFR 835.605 - Labeling items and containers.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Labeling items and containers. 835.605 Section 835.605... items and containers. Except as provided at § 835.606, each item or container of radioactive material... information to permit individuals handling, using, or working in the vicinity of the items or containers to...

  4. 41 CFR 101-27.404 - Review of items.

    Science.gov (United States)

    2010-07-01

    ... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true Review of items. 101-27.404 Section 101-27.404 Public Contracts and Property Management Federal Property Management...-Elimination of Items From Inventory § 101-27.404 Review of items. Except for standby or reserve stocks, items...

  5. Australian Chemistry Test Item Bank: Years 11 & 12. Volume 1.

    Science.gov (United States)

    Commons, C., Ed.; Martin, P., Ed.

    Volume 1 of the Australian Chemistry Test Item Bank, consisting of two volumes, contains nearly 2000 multiple-choice items related to the chemistry taught in Year 11 and Year 12 courses in Australia. Items which were written during 1979 and 1980 were initially published in the "ACER Chemistry Test Item Collection" and in the "ACER…

  6. ACER Chemistry Test Item Collection. ACER Chemtic Year 12.

    Science.gov (United States)

    Australian Council for Educational Research, Hawthorn.

    The chemistry test item banks contains 225 multiple-choice questions suitable for diagnostic and achievement testing; a three-page teacher's guide; answer key with item facilities; an answer sheet; and a 45-item sample achievement test. Although written for the new grade 12 chemistry course in Victoria, Australia, the items are widely applicable.…

  7. Utilizing Response Time Distributions for Item Selection in CAT

    Science.gov (United States)

    Fan, Zhewen; Wang, Chun; Chang, Hua-Hua; Douglas, Jeffrey

    2012-01-01

    Traditional methods for item selection in computerized adaptive testing only focus on item information without taking into consideration the time required to answer an item. As a result, some examinees may receive a set of items that take a very long time to finish, and information is not accrued as efficiently as possible. The authors propose two…

  8. A Review of Classical Methods of Item Analysis.

    Science.gov (United States)

    French, Christine L.

    Item analysis is a very important consideration in the test development process. It is a statistical procedure to analyze test items that combines methods used to evaluate the important characteristics of test items, such as difficulty, discrimination, and distractibility of the items in a test. This paper reviews some of the classical methods for…

  9. University Students Alternative Conceptions On Circular Motion

    Directory of Open Access Journals (Sweden)

    Ian Phil Canlas

    2015-08-01

    Full Text Available This study attempted to find out university students alternative conceptions on circular motion. An 18-item researcher-compiled and content-validated questionnaire was administered to twenty-six 26 students taking up a program in Bachelor in Secondary Education-Physical Science in their second year enrolled in a course on mechanics. Results revealed that majority of the students possess alternative conceptions on circular motion specifically along velocity acceleration and force. Moreover results showed the inconsistencies in the students understanding of circular motion concepts.

  10. Generalizing quasinormality

    Directory of Open Access Journals (Sweden)

    John Cossey

    2015-03-01

    Full Text Available Quasinormal subgroups have been studied for nearly 80 years. In finite groups, questions concerning them invariably reduce to p-groups, and here they have the added interest of being invariant under projectivities, unlike normal subgroups. However, it has been shown recently that certain groups, constructed by Berger and Gross in 1982, of an important universal nature with regard to the existence of core-free quasinormal subgroups gener- ally, have remarkably few such subgroups. Therefore in order to overcome this misfortune, a generalization of the concept of quasi- normality will be defined. It could be the beginning of a lengthy undertaking. But some of the initial findings are encouraging, in particular the fact that this larger class of subgroups also remains invariant under projectivities of finite p-groups, thus connecting group and subgroup lattice structures.

  11. Differential item functioning analysis of the Vanderbilt Expertise Test for cars.

    Science.gov (United States)

    Lee, Woo-Yeol; Cho, Sun-Joo; McGugin, Rankin W; Van Gulick, Ana Beth; Gauthier, Isabel

    2015-01-01

    The Vanderbilt Expertise Test for cars (VETcar) is a test of visual learning for contemporary car models. We used item response theory to assess the VETcar and in particular used differential item functioning (DIF) analysis to ask if the test functions the same way in laboratory versus online settings and for different groups based on age and gender. An exploratory factor analysis found evidence of multidimensionality in the VETcar, although a single dimension was deemed sufficient to capture the recognition ability measured by the test. We selected a unidimensional three-parameter logistic item response model to examine item characteristics and subject abilities. The VETcar had satisfactory internal consistency. A substantial number of items showed DIF at a medium effect size for test setting and for age group, whereas gender DIF was negligible. Because online subjects were on average older than those tested in the lab, we focused on the age groups to conduct a multigroup item response theory analysis. This revealed that most items on the test favored the younger group. DIF could be more the rule than the exception when measuring performance with familiar object categories, therefore posing a challenge for the measurement of either domain-general visual abilities or category-specific knowledge.

  12. Item analysis and evaluation in the examinations in the faculty of ...

    African Journals Online (AJOL)

    2014-11-05

    Nov 5, 2014 ... Key words: Classical test theory, item analysis, item difficulty, item discrimination, item response theory, reliability ... the probability of answering an item correctly or of attaining ..... A Monte Carlo comparison of item and person.

  13. Development of the Open Items Tracking System

    International Nuclear Information System (INIS)

    Riggi, V.

    1994-01-01

    The West Valley Demonstration Project, located on the site of the only commercial nuclear fuel reprocessing facility to have operated in USA, has the directed objectives of solidifying the high-level radioactive waste into a durable, solid form for shipment; decontaminating and decommissioning the tanks and facilities; and disposing of the resulting low-level and transuranic wastes. Since an escalating trend of open work items was noticed in the Fall of 1988, and there was no control mechanism for tracking and closing the open items, a Work Control System was developed for this purpose. It is self-contained system on a mainframe ARTEMIS 9000, which tracks, monitors, and closes out external commitments in a timely manner. Audits, surveillances, site appraisals, preventive maintenance, instrument calibration recall, and scheduling are covered

  14. Effect of study context on item recollection.

    Science.gov (United States)

    Skinner, Erin I; Fernandes, Myra A

    2010-07-01

    We examined how visual context information provided during encoding, and unrelated to the target word, affected later recollection for words presented alone using a remember-know paradigm. Experiments 1A and 1B showed that participants had better overall memory-specifically, recollection-for words studied with pictures of intact faces than for words studied with pictures of scrambled or inverted faces. Experiment 2 replicated these results and showed that recollection was higher for words studied with pictures of faces than when no image accompanied the study word. In Experiment 3 participants showed equivalent memory for words studied with unique faces as for those studied with a repeatedly presented face. Results suggest that recollection benefits when visual context information high in meaningful content accompanies study words and that this benefit is not related to the uniqueness of the context. We suggest that participants use elaborative processes to integrate item and meaningful contexts into ensemble information, improving subsequent item recollection.

  15. Development of an item bank for food parenting practices based on published instruments and reports from Canadian and US parents.

    Science.gov (United States)

    O'Connor, Teresia M; Pham, Truc; Watts, Allison W; Tu, Andrew W; Hughes, Sheryl O; Beauchamp, Mark R; Baranowski, Tom; Mâsse, Louise C

    2016-08-01

    Research to understand how parents influence their children's dietary intake and eating behaviors has expanded in the past decades and a growing number of instruments are available to assess food parenting practices. Unfortunately, there is no consensus on how constructs should be defined or operationalized, making comparison of results across studies difficult. The aim of this study was to develop a food parenting practice item bank with items from published scales and supplement with parenting practices that parents report using. Items from published scales were identified from two published systematic reviews along with an additional systematic review conducted for this study. Parents (n = 135) with children 5-12 years old from the US and Canada, stratified to represent the demographic distribution of each country, were recruited to participate in an online semi-qualitative survey on food parenting. Published items and parent responses were coded using the same framework to reduce the number of items into representative concepts using a binning and winnowing process. The literature contributed 1392 items and parents contributed 1985 items, which were reduced to 262 different food parenting concepts (26% exclusive from literature, 12% exclusive from parents, and 62% represented in both). Food parenting practices related to 'Structure of Food Environment' and 'Behavioral and Educational' were emphasized more by parent responses, while practices related to 'Consistency of Feeding Environment' and 'Emotional Regulation' were more represented among published items. The resulting food parenting item bank should next be calibrated with item response modeling for scientists to use in the future. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Basic concepts of materials accounting

    International Nuclear Information System (INIS)

    Markin, J.T.

    1989-01-01

    The importance of accounting for nuclear materials to the efficient, safe, and economical operation of nuclear facilities is introduced, and the following topics are covered: material balance equation; item control areas; material balance uncertainty; decision procedures for materials accounting; conventional and near-real-time accounting; regulatory requirements of the US Department of Energy and the Nuclear Regulatory Commission; and a summary related to the development of a materials accounting system to implement the basic concepts described. The summary includes a section on each of the following: problem definition, system objectives, and system design

  17. Changes in the nutritional quality of fast-food items marketed at restaurants, 2010 v. 2013.

    Science.gov (United States)

    Soo, Jackie; Harris, Jennifer L; Davison, Kirsten K; Williams, David R; Roberto, Christina A

    2018-03-27

    To examine the nutritional quality of menu items promoted in four (US) fast-food restaurant chains (McDonald's, Burger King, Wendy's, Taco Bell) in 2010 and 2013. Menu items pictured on signs and menu boards were recorded at 400 fast-food restaurants across the USA. The Nutrient Profile Index (NPI) was used to calculate overall nutrition scores for items (higher scores indicate greater nutritional quality) and was dichotomized to denote healthier v. less healthy items. Changes over time in NPI scores and energy of promoted foods and beverages were analysed using linear regression. Four hundred fast-food restaurants (McDonald's, Burger King, Wendy's, Taco Bell; 100 locations per chain). NPI of fast-food items marketed at fast-food restaurants. Promoted foods and beverages on general menu boards and signs remained below the 'healthier' cut-off at both time points. On general menu boards, pictured items became modestly healthier from 2010 to 2013, increasing (mean (se)) by 3·08 (0·16) NPI score points (Prestaurants showed limited improvements in nutritional quality in 2013 v. 2010.

  18. Validation and Structural Analysis of the Kinematics Concept Test

    Science.gov (United States)

    Lichtenberger, A.; Wagner, C.; Hofer, S. I.; Stem, E.; Vaterlaus, A.

    2017-01-01

    The kinematics concept test (KCT) is a multiple-choice test designed to evaluate students' conceptual understanding of kinematics at the high school level. The test comprises 49 multiple-choice items about velocity and acceleration, which are based on seven kinematic concepts and which make use of three different representations. In the first part…

  19. Development of the Statistical Reasoning in Biology Concept Inventory (SRBCI)

    Science.gov (United States)

    Deane, Thomas; Nomme, Kathy; Jeffery, Erica; Pollock, Carol; Birol, Gülnur

    2016-01-01

    We followed established best practices in concept inventory design and developed a 12-item inventory to assess student ability in statistical reasoning in biology (Statistical Reasoning in Biology Concept Inventory [SRBCI]). It is important to assess student thinking in this conceptual area, because it is a fundamental requirement of being…

  20. Daily dynamics of personal identity and self-concept clarity

    NARCIS (Netherlands)

    Schwartz, S.J.; Klimstra, T.A.; Luyckx, K.; Hale, W.W.; Frijns, T.; Oosterwegel, A.; van Lier, P.A.C.; Koot, H.M.; Meeus, W.H.J.

    2011-01-01

    We examined the daily dynamics among self-concept clarity and identity processes, and their effects on distress, among a sample of 580 Dutch adolescents. Participants completed measures of identity, self-concept clarity, anxiety and depression at annual intervals; and daily single-item measures of

  1. 17 CFR 260.7a-16 - Inclusion of items, differentiation between items and answers, omission of instructions.

    Science.gov (United States)

    2010-04-01

    ... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Inclusion of items, differentiation between items and answers, omission of instructions. 260.7a-16 Section 260.7a-16 Commodity and... INDENTURE ACT OF 1939 Formal Requirements § 260.7a-16 Inclusion of items, differentiation between items and...

  2. Comparing large lecture mechanics curricula using the Force Concept Inventory: A five thousand student study

    Science.gov (United States)

    Caballero, Marcos D.; Greco, Edwin F.; Murray, Eric R.; Bujak, Keith R.; Jackson Marr, M.; Catrambone, Richard; Kohlmyer, Matthew A.; Schatz, Michael F.

    2012-07-01

    The performance of over 5000 students in introductory calculus-based mechanics courses at the Georgia Institute of Technology was assessed using the Force Concept Inventory (FCI). Results from two different curricula were compared: a traditional mechanics curriculum and the Matter & Interactions (M&I) curriculum. Both were taught with similar interactive pedagogy. Post-instruction FCI averages were significantly higher for the traditional curriculum than for the M&I curriculum; the differences between curricula persist after accounting for factors such as pre-instruction FCI scores, grade point averages, and SAT scores. FCI performance on categories of items organized by concepts was also compared; traditional averages were significantly higher in each concept. We examined differences in student preparation between the curricula and found that the relative fraction of homework and lecture topics devoted to FCI force and motion concepts correlated with the observed performance differences. Concept inventories, as instruments for evaluating curricular reforms, are generally limited to the particular choice of content and goals of the instrument. Moreover, concept inventories fail to measure what are perhaps the most interesting aspects of reform: the non-overlapping content and goals that are not present in courses without reform.

  3. Book Review: The Architecture of Concepts: The Historical Formation of Human Rights

    Directory of Open Access Journals (Sweden)

    Scott Nicholas Romaniuk

    2014-12-01

    Full Text Available How do concepts come to be? And, in particular, how current conceptions of international human rights are built upon a particular conceptual architecture? Peter de Bolla, author of The Architecture of Concepts: The Historical Formation of Human Rights, addresses these questions in incremental steps, building on what scholars currently understand when it comes to concepts more generally. The methodology is based on the use of the Eighteenth Century Collection Online (ECCO digital archives predominantly, with the aim of constructing data-dependent descriptions of conceptual architectures. The author, thus, looks at conceptual networks and the extensive relationships found within them so as to direct researchers in conducting future plotting of connectivities within networks. The opening chapter looks at concepts as a way of thinking. Concepts are treated as a metaphorical “subway or tube maps project into multiple dimensions.” The author then focuses on the eighteenth century and its printed materials. The use of large data allows the author to extrapolate matters of language spanning large communities. The following chapters combine the issue of creating conceptual dispositions with poignant debates about rights that pervaded the First Continental Congress during the 1770s, while repositioning the items of inquiry, mentioned previously, by challenging the assumption of the origin(s of human rights.

  4. General general game AI

    OpenAIRE

    Togelius, Julian; Yannakakis, Georgios N.; 2016 IEEE Conference on Computational Intelligence and Games (CIG)

    2016-01-01

    Arguably the grand goal of artificial intelligence research is to produce machines with general intelligence: the capacity to solve multiple problems, not just one. Artificial intelligence (AI) has investigated the general intelligence capacity of machines within the domain of games more than any other domain given the ideal properties of games for that purpose: controlled yet interesting and computationally hard problems. This line of research, however, has so far focuse...

  5. Dissociating the neural correlates of intra-item and inter-item working-memory binding.

    Directory of Open Access Journals (Sweden)

    Carinne Piekema

    Full Text Available BACKGROUND: Integration of information streams into a unitary representation is an important task of our cognitive system. Within working memory, the medial temporal lobe (MTL has been conceptually linked to the maintenance of bound representations. In a previous fMRI study, we have shown that the MTL is indeed more active during working-memory maintenance of spatial associations as compared to non-spatial associations or single items. There are two explanations for this result, the mere presence of the spatial component activates the MTL, or the MTL is recruited to bind associations between neurally non-overlapping representations. METHODOLOGY/PRINCIPAL FINDINGS: The current fMRI study investigates this issue further by directly comparing intrinsic intra-item binding (object/colour, extrinsic intra-item binding (object/location, and inter-item binding (object/object. The three binding conditions resulted in differential activation of brain regions. Specifically, we show that the MTL is important for establishing extrinsic intra-item associations and inter-item associations, in line with the notion that binding of information processed in different brain regions depends on the MTL. CONCLUSIONS/SIGNIFICANCE: Our findings indicate that different forms of working-memory binding rely on specific neural structures. In addition, these results extend previous reports indicating that the MTL is implicated in working-memory maintenance, challenging the classic distinction between short-term and long-term memory systems.

  6. Evaluating rivastigmine in mild-to-moderate Parkinson's disease dementia using ADAS-cog items.

    Science.gov (United States)

    Schmitt, Frederick A; Aarsland, Dag; Brønnick, Kolbjørn S; Meng, Xiangyi; Tekin, Sibel; Olin, Jason T

    2010-08-01

    Rivastigmine has been shown to improve cognition in patients with Parkinson's disease dementia (PDD). To further explore the impact of anticholinesterase therapy on PDD, Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-cog) items were assessed in a retrospective analysis of a 24-week, double-blind, placebo-controlled trial of rivastigmine. Mean changes from baseline at week 24 were calculated for ADAS-cog item scores and for 3 cognitive domain scores. A total of 362 patients were randomized to 3 to 12 mg/d rivastigmine capsules and 179 to placebo. Patients with PDD receiving rivastigmine improved versus placebo on items: word recall, following commands, ideational praxis, remembering test instructions, and comprehension of spoken language (P ADAS-cog is sensitive to broad cognitive changes in PDD. Overall, rivastigmine was associated with improvements on individual cognitive items and general cognitive domains.

  7. Ohio dentists' awareness and incorporation of the dental home concept.

    Science.gov (United States)

    Hammersmith, Kimberly J; Siegal, Mark D; Casamassimo, Paul S; Amini, Homa

    2013-06-01

    The authors measured the awareness of the dental home concept among pediatric dentists (PDs) and general practice dentists (GPs) in Ohio and determined whether they included dental home characteristics for children 5 years and younger into their practices. The authors sent a pretested 20-question survey to all Ohio PDs and to a random sample of approximately 20 percent of GPs in Ohio. The authors designed the survey to elicit information about dental home awareness and the extent to which dental home characteristics were incorporated into dental practices. More than 90 percent of both GPs and PDs incorporated or intended to incorporate into their dental practices the specific dental home characteristics mentioned in 20 of 41 items related to dental home characteristics. Of the respondents who did not already incorporate dental home characteristics into their practices, however, most did not intend to do so. Less than 50 percent of respondents in both groups responded positively to some items in the culturally effective group, and GPs were less likely than were PDs to provide a range of behavior management services and to provide treatment for patients with complex medical and dental treatment needs. PDs were more likely than were GPs to accept Ohio Medicaid (64 versus 33 percent). PDs were more likely than were GPs (78 versus 18 percent) to be familiar with the term "dental home." More recent dental school graduates were more familiar with the term. Most Ohio PDs' and GPs' practices included characteristics found in the definition of dental home, despite a general lack of concept awareness on the part of GPs. Research is needed to provide an evidence base for the dental home. Practical Implications. Once an evidence base is developed for the important aspects of the dental home and the definition is revised, efforts should be made to incorporate these aspects more broadly into dental practice.

  8. Content Validity and Psychometric Characteristics of the "Knowledge about Older Patients Quiz" for Nurses Using Item Response Theory.

    Science.gov (United States)

    Dikken, Jeroen; Hoogerduijn, Jita G; Kruitwagen, Cas; Schuurmans, Marieke J

    2016-11-01

    To assess the content validity and psychometric characteristics of the Knowledge about Older Patients Quiz (KOP-Q), which measures nurses' knowledge regarding older hospitalized adults and their certainty regarding this knowledge. Cross-sectional. Content validity: general hospitals. Psychometric characteristics: nursing school and general hospitals in the Netherlands. Content validity: 12 nurse specialists in geriatrics. Psychometric characteristics: 107 first-year and 78 final-year bachelor of nursing students, 148 registered nurses, and 20 nurse specialists in geriatrics. Content validity: The nurse specialists rated each item of the initial KOP-Q (52 items) on relevance. Ratings were used to calculate Item-Content Validity Index and average Scale-Content Validity Index (S-CVI/ave) scores. Items with insufficient content validity were removed. Psychometric characteristics: Ratings of students, nurses, and nurse specialists were used to test for different item functioning (DIF) and unidimensionality before item characteristics (discrimination and difficulty) were examined using Item Response Theory. Finally, norm references were calculated and nomological validity was assessed. Content validity: Forty-three items remained after assessing content validity (S-CVI/ave = 0.90). Psychometric characteristics: Of the 43 items, two demonstrating ceiling effects and 11 distorting ability estimates (DIF) were subsequently excluded. Item characteristics were assessed for the remaining 30 items, all of which demonstrated good discrimination and difficulty parameters. Knowledge was positively correlated with certainty about this knowledge. The final 30-item KOP-Q is a valid, psychometrically sound, comprehensive instrument that can be used to assess the knowledge of nursing students, hospital nurses, and nurse specialists in geriatrics regarding older hospitalized adults. It can identify knowledge and certainty deficits for research purposes or serve as a tool in educational

  9. An introduction to Item Response Theory and Rasch Analysis of the Eating Assessment Tool (EAT-10).

    Science.gov (United States)

    Kean, Jacob; Brodke, Darrel S; Biber, Joshua; Gross, Paul

    2018-03-01

    Item response theory has its origins in educational measurement and is now commonly applied in health-related measurement of latent traits, such as function and symptoms. This application is due in large part to gains in the precision of measurement attributable to item response theory and corresponding decreases in response burden, study costs, and study duration. The purpose of this paper is twofold: introduce basic concepts of item response theory and demonstrate this analytic approach in a worked example, a Rasch model (1PL) analysis of the Eating Assessment Tool (EAT-10), a commonly used measure for oropharyngeal dysphagia. The results of the analysis were largely concordant with previous studies of the EAT-10 and illustrate for brain impairment clinicians and researchers how IRT analysis can yield greater precision of measurement.

  10. Measuring everyday functional competence using the Rasch assessment of everyday activity limitations (REAL) item bank.

    Science.gov (United States)

    Oude Voshaar, Martijn A H; Ten Klooster, Peter M; Vonkeman, Harald E; van de Laar, Mart A F J

    2017-11-01

    Traditional patient-reported physical function instruments often poorly differentiate patients with mild-to-moderate disability. We describe the development and psychometric evaluation of a generic item bank for measuring everyday activity limitations in outpatient populations. Seventy-two items generated from patient interviews and mapped to the International Classification of Functioning, Disability and Health (ICF) domestic life chapter were administered to 1128 adults representative of the Dutch population. The partial credit model was fitted to the item responses and evaluated with respect to its assumptions, model fit, and differential item functioning (DIF). Measurement performance of a computerized adaptive testing (CAT) algorithm was compared with the SF-36 physical functioning scale (PF-10). A final bank of 41 items was developed. All items demonstrated acceptable fit to the partial credit model and measurement invariance across age, sex, and educational level. Five- and ten-item CAT simulations were shown to have high measurement precision, which exceeded that of SF-36 physical functioning scale across the physical function continuum. Floor effects were absent for a 10-item empirical CAT simulation, and ceiling effects were low (13.5%) compared with SF-36 physical functioning (38.1%). CAT also discriminated better than SF-36 physical functioning between age groups, number of chronic conditions, and respondents with or without rheumatic conditions. The Rasch assessment of everyday activity limitations (REAL) item bank will hopefully prove a useful instrument for assessing everyday activity limitations. T-scores obtained using derived measures can be used to benchmark physical function outcomes against the general Dutch adult population.

  11. CTTITEM: SAS macro and SPSS syntax for classical item analysis.

    Science.gov (United States)

    Lei, Pui-Wa; Wu, Qiong

    2007-08-01

    This article describes the functions of a SAS macro and an SPSS syntax that produce common statistics for conventional item analysis including Cronbach's alpha, item difficulty index (p-value or item mean), and item discrimination indices (D-index, point biserial and biserial correlations for dichotomous items and item-total correlation for polytomous items). These programs represent an improvement over the existing SAS and SPSS item analysis routines in terms of completeness and user-friendliness. To promote routine evaluations of item qualities in instrument development of any scale, the programs are available at no charge for interested users. The program codes along with a brief user's manual that contains instructions and examples are downloadable from suen.ed.psu.edu/-pwlei/plei.htm.

  12. Implicit theories of online trolling: Evidence that attention-seeking conceptions are associated with increased psychological resilience.

    Science.gov (United States)

    Maltby, John; Day, Liz; Hatcher, Ruth M; Tazzyman, Sarah; Flowe, Heather D; Palmer, Emma J; Frosch, Caren A; O'Reilly, Michelle; Jones, Ceri; Buckley, Chloe; Knieps, Melanie; Cutts, Katie

    2016-08-01

    Three studies were conducted to investigate people's conceptions of online trolls, particularly conceptions associated with psychological resilience to trolling. In Study 1, a factor analysis of participants' ratings of characteristics of online trolls found a replicable bifactor model of conceptions of online trolls, with a general factor of general conceptions towards online trolls being identified, but five group factors (attention-conflict seeking, low self-confidence, viciousness, uneducated, amusement) as most salient. In Study 2, participants evaluated hypothetical profiles of online trolling messages to establish the validity of the five factors. Three constructs (attention-conflict seeking, viciousness, and uneducated) were actively employed when people considered profiles of online trolling scenarios. Study 3 introduced a 20-item 'Conceptions of Online Trolls scale' to examine the extent to which the five group factors were associated with resilience to trolling. Results indicated that viewing online trolls as seeking conflict or attention was associated with a decrease in individuals' negative affect around previous trolling incidents. Overall, the findings suggest that adopting an implicit theories approach can further our understanding and measurement of conceptions towards trolling through the identification of five salient factors, of which at least one factor may act as a resilience strategy. © 2015 The British Psychological Society.

  13. Social Concepts and Judgments: A Semantic Differential Analysis of the Concepts Feminist, Man, and Woman

    Science.gov (United States)

    Pierce, W. David; Sydie, R. A.; Stratkotter, Rainer

    2003-01-01

    Male and female participants (N = 274) made judgments about the social concepts of "feminist," "man," and "woman" on 63 semantic differential items. Factor analysis identified three basic dimensions termed evaluative, potency, and activity as well as two secondary factors called expressiveness and sexuality. Results for the evaluative dimension…

  14. Control of Suspect/Counterfeit and Defective Items

    Energy Technology Data Exchange (ETDEWEB)

    Sheriff, Marnelle L.

    2013-09-03

    This procedure implements portions of the requirements of MSC-MP-599, Quality Assurance Program Description. It establishes the Mission Support Alliance (MSA) practices for minimizing the introduction of and identifying, documenting, dispositioning, reporting, controlling, and disposing of suspect/counterfeit and defective items (S/CIs). employees whose work scope relates to Safety Systems (i.e., Safety Class [SC] or Safety Significant [SS] items), non-safety systems and other applications (i.e., General Service [GS]) where engineering has determined that their use could result in a potential safety hazard. MSA implements an effective Quality Assurance (QA) Program providing a comprehensive network of controls and verification providing defense-in-depth by preventing the introduction of S/CIs through the design, procurement, construction, operation, maintenance, and modification of processes. This procedure focuses on those safety systems, and other systems, including critical load paths of lifting equipment, where the introduction of S/CIs would have the greatest potential for creating unsafe conditions.

  15. Checking Equity: Why Differential Item Functioning Analysis Should Be a Routine Part of Developing Conceptual Assessments

    Czech Academy of Sciences Publication Activity Database

    Martinková, Patrícia; Drabinová, Adéla; Liaw, Y.L.; Sanders, E.A.; McFarland, J.L.; Price, R.M.

    2017-01-01

    Roč. 16, č. 2 (2017), č. článku rm2. ISSN 1931-7913 R&D Projects: GA ČR GJ15-15856Y Grant - others:NSF(US) DUE-1043443 Institutional support: RVO:67985807 Keywords : differential item functioning * fairness * conceptual assessments * concept inventory * undergraduate education * bias Subject RIV: AM - Education OBOR OECD: Education , special (to gifted persons, those with learning disabilities) Impact factor: 3.930, year: 2016

  16. A review of the effects on IRT item parameter estimates with a focus on misbehaving common items in test equating

    Directory of Open Access Journals (Sweden)

    Michalis P Michaelides

    2010-10-01

    Full Text Available Many studies have investigated the topic of change or drift in item parameter estimates in the context of Item Response Theory. Content effects, such as instructional variation and curricular emphasis, as well as context effects, such as the wording, position, or exposure of an item have been found to impact item parameter estimates. The issue becomes more critical when items with estimates exhibiting differential behavior across test administrations are used as common for deriving equating transformations. This paper reviews the types of effects on IRT item parameter estimates and focuses on the impact of misbehaving or aberrant common items on equating transformations. Implications relating to test validity and the judgmental nature of the decision to keep or discard aberrant common items are discussed, with recommendations for future research into more informed and formal ways of dealing with misbehaving common items.

  17. A Review of the Effects on IRT Item Parameter Estimates with a Focus on Misbehaving Common Items in Test Equating.

    Science.gov (United States)

    Michaelides, Michalis P

    2010-01-01

    Many studies have investigated the topic of change or drift in item parameter estimates in the context of item response theory (IRT). Content effects, such as instructional variation and curricular emphasis, as well as context effects, such as the wording, position, or exposure of an item have been found to impact item parameter estimates. The issue becomes more critical when items with estimates exhibiting differential behavior across test administrations are used as common for deriving equating transformations. This paper reviews the types of effects on IRT item parameter estimates and focuses on the impact of misbehaving or aberrant common items on equating transformations. Implications relating to test validity and the judgmental nature of the decision to keep or discard aberrant common items are discussed, with recommendations for future research into more informed and formal ways of dealing with misbehaving common items.

  18. Psychometric Properties of the Heart Disease Knowledge Scale: Evidence from Item and Confirmatory Factor Analyses.

    Science.gov (United States)

    Lim, Bee Chiu; Kueh, Yee Cheng; Arifin, Wan Nor; Ng, Kok Huan

    2016-07-01

    Heart disease knowledge is an important concept for health education, yet there is lack of evidence on proper validated instruments used to measure levels of heart disease knowledge in the Malaysian context. A cross-sectional, survey design was conducted to examine the psychometric properties of the adapted English version of the Heart Disease Knowledge Questionnaire (HDKQ). Using proportionate cluster sampling, 788 undergraduate students at Universiti Sains Malaysia, Malaysia, were recruited and completed the HDKQ. Item analysis and confirmatory factor analysis (CFA) were used for the psychometric evaluation. Construct validity of the measurement model was included. Most of the students were Malay (48%), female (71%), and from the field of science (51%). An acceptable range was obtained with respect to both the difficulty and discrimination indices in the item analysis results. The difficulty index ranged from 0.12-0.91 and a discrimination index of ≥ 0.20 were reported for the final retained 23 items. The final CFA model showed an adequate fit to the data, yielding a 23-item, one-factor model [weighted least squares mean and variance adjusted scaled chi-square difference = 1.22, degrees of freedom = 2, P-value = 0.544, the root mean square error of approximation = 0.03 (90% confidence interval = 0.03, 0.04); close-fit P-value = > 0.950]. Adequate psychometric values were obtained for Malaysian undergraduate university students using the 23-item, one-factor model of the adapted HDKQ.

  19. Diagnosing Students’ conception on atomic structure using open ended questions

    Science.gov (United States)

    Fitriza, Z.; Gazali, F.

    2018-05-01

    This study aims to diagnose students’ conception on atomic structure concepts using open ended questions. For this reason, a 7 items of assay test was administered to 135 senior high school students from different schools in West Sumatera. The data were collected using a an open ended test which is covering the concept used in the topic Atomic Structure. The open ended test of students’ conceptual was developed to identify the alternative conceptions that student might have regarding the concepts in Atomic Structure, to measure the level of students’ conceptions, and the way of students’ thinking concerning the concepts. The results showed that students find difficulties about some concepts of Atomic structure such as atom, atomic model, electron configuration, period and group.The result of this study illuminated the concepts to be underlined in developing teaching and learning approach concerning the topic of Atomic Structure.

  20. Analysis of the ENADE items complexity based on the Revised Bloom Taxonomy: contributions to physics teaching

    Directory of Open Access Journals (Sweden)

    João Paulo de Castro Costa

    2017-12-01

    Full Text Available The National Student Performance Exam (ENADE is the main component of the National Higher Education Evaluation System (SINAES that deals with the Brazilian Higher Education Degrees. This article deals with 120 (one hundred and twenty objectives and discursive items from four ENADE editions for Teaching Physics Degree, applied in 2005, 2008, 2011 and 2014. We search for the Exam complexity throughout cognitive aspects mobilized to solve each item, according to the Bloom Taxonomy Revised (BTR. The BTR proposes a two-dimensional matrix classification that crosses a knowledge dimension, which means, “what” students must know in order to answer the questions, with the cognitive process involved in the task, reflecting “how” the problem was solved. According the BTR theory, the knowledge has been understood in the dimensions: effective, conceptual, procedure and metacognitive, which deals, respectively with basics terminology knowledge, concepts knowledge, procedure methodology knowledge and reflexive/analytical knowledge. The cognitive process described in verbs at the BTR presents the student´s skills in the resolutions ranked as: to remember, to understand, to apply, to analyze, to evaluate and to create. To classify discursive items, pattern answers were used, and to classify multiple choice items, our resolutions of the questions were used. The items were located at the two-dimensional BTR matrix, which gives us an Exam complexity overview. We observe that only 17 (14% items are in the effective knowledge domain, while 103 (86% items require the conceptual and procedure knowledge domain, which demands higher complexity. We consider these results compatible with the ENADE role as a Higher Brazilian Education quality referential. We intend to update Physics professors throughout Physics Teaching Examination in order to increase their commitment to the Higher Education Evaluation. We also believe that understanding the examination could