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Sample records for applying item response

  1. Development of an Item Bank of Order and Graph by Applying Multidimensional Item Response Theory

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    Somprasong Senarat

    2012-08-01

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    This study aimed to develop an item bank of Order and Graph of Mattayomsuksa 1 level (grade 7. The samples were 4,800 lower secondary students from 34 schools in northeastern area of Thailand, academic year 2011 chosen through multi-stage random sampling. The research tool used in the study was a multiple choicetest of an Order and Graph lesson by applying multidimensional item response theory. Parameter were analyzed by confi rmatory factor analysis by applying multidimensional normalogive model with guessing of the program normalogive harmonic analysis robust method (NOHARM. Discrimination power and Easiness intercept were equated through non–orthogonal procrustes method. The study results indicated that there were 59 items out of 140 passed the test standard.

    Key words: Item bank; Cognitive process; Multidimensional item response theory (MIRT

  2. Structure and Measurement of Depression in Youths: Applying Item Response Theory to Clinical Data

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    Cole, David A.; Cai, Li; Martin, Nina C.; Findling, Robert L.; Youngstrom, Eric A.; Garber, Judy; Curry, John F.; Hyde, Janet S.; Essex, Marilyn J.; Compas, Bruce E.; Goodyer, Ian M.; Rohde, Paul; Stark, Kevin D.; Slattery, Marcia J.; Forehand, Rex

    2011-01-01

    Our goals in this article were to use item response theory (IRT) to assess the relation of depressive symptoms to the underlying dimension of depression and to demonstrate how IRT-based measurement strategies can yield more reliable data about depression severity than conventional symptom counts. Participants were 3,403 children and adolescents…

  3. Generalizability theory and item response theory

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    Glas, C.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 s

  4. Automated Item Selection Using Item Response Theory.

    Science.gov (United States)

    Stocking, Martha L.; And Others

    This paper presents a new heuristic approach to interactive test assembly that is called the successive item replacement algorithm. This approach builds on the work of W. J. van der Linden (1987) and W. J. van der Linden and E. Boekkooi-Timminga (1989) in which methods of mathematical optimization are combined with item response theory to…

  5. Thermal response based item identification.

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    Smith, M. K. (Morag K.); Hypes, P. A. (Philip A.); Bracken, D. S. (David S.)

    2001-01-01

    One of the most difficult problems in NDA of nuclear materials is identifying the chemical form of the nuclear material and the surrounding matrix. Recent work analyzing the calorimeter response of sources embedded in a variety of matrices has led to a possible solution to this problem. The wide range of thermal time constants exhibited by typical matrix materials lends itself to permitting the differentiation between materials, based on time constants extracted from the measured response. Potential applications include simple item identification, item fingerprinting as part of shipper-receiver measurements, and distinguishing between Pu metal and Pu oxide as required under certain proposed attribute measurements. The results of applying this technique to a variety of items will be presented and discussed.

  6. Thermal response based item identification

    International Nuclear Information System (INIS)

    One of the most difficult problems in NDA of nuclear materials is identifying the chemical form of the nuclear material and the surrounding matrix. Recent work analyzing the calorimeter response of sources embedded in a variety of matrices has led to a possible solution to this problem. The wide range of thermal time constants exhibited by typical matrix materials lends itself to permitting the differentiation between materials, based on time constants extracted from the measured response. Potential applications include simple item identification, item fingerprinting as part of shipper-receiver measurements, and distinguishing between Pu metal and Pu oxide as required under certain proposed attribute measurements. The results of applying this technique to a variety of items will be presented and discussed.

  7. Measuring Student Learning with Item Response Theory

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    Lee, Young-Jin; Palazzo, David J.; Warnakulasooriya, Rasil; Pritchard, David E.

    2008-01-01

    We investigate short-term learning from hints and feedback in a Web-based physics tutoring system. Both the skill of students and the difficulty and discrimination of items were determined by applying item response theory (IRT) to the first answers of students who are working on for-credit homework items in an introductory Newtonian physics…

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

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    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. PMID:25106393

  9. Teoria da resposta ao item aplicada ao Inventário de Depressão Beck Item response theory applied to the Beck Depression Inventory

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    Stela Maris de Jezus Castro

    2010-09-01

    Full Text Available O Inventário de Depressão Beck (BDI, uma escala que mede o traço latente de intensidade de sintomas depressivos, pode ser avaliado através da Teoria da Resposta ao Item (TRI. Este estudo utilizou o modelo TRI de Resposta Gradual na avaliação da intensidade de sintomas depressivos de 4.025 indivíduos que responderam ao BDI, de modo a explorar eficientemente a informação disponível nos diferentes aspectos possibilitados pelo uso desta metodologia. O ajuste foi efetuado no software PARSCALE. Foram identificados 13 itens do BDI nos quais pelo menos uma categoria de resposta não tinha chance maior que as demais de ser escolhida, de modo que estes itens tiveram de ser recategorizados. Os itens com maior capacidade de discriminação são relativos à tristeza, pessimismo, sentimento de fracasso, insatisfação, auto-aversão, indecisão e dificuldade para trabalhar. Os itens mais graves são aqueles relacionados com perda de peso, retraimento social e idéias suicidas. O grupo dos 202 indivíduos com as maiores intensidades de sintomas depressivos foi composto por 74% de mulheres, e praticamente 84% possuíam diagnóstico de algum transtorno psiquiátrico. Os resultados evidenciam alguns dos inúmeros ganhos advindos da utilização da TRI na análise de traços latentes.The Beck Depression Inventory (BDI, a scale that measures the latent trait intensity of depression symptoms, can be assessed by the Item Response Theory (IRT. This study used the Graded-Response model (GRM to assess the intensity of depressive symptoms in 4,025 individuals who responded to the BDI, in order to efficiently use the information available on different aspects enabled by the use of this methodology. The fit of this model was done in PARSCALE software. We identified 13 items of the BDI in which at least one response category was not more likely than others to be chosen, so that these items had to be categorized again. The items with greater power of

  10. A Mixed Effects Randomized Item Response Model

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    Fox, J.-P.; Wyrick, Cheryl

    2008-01-01

    The randomized response technique ensures that individual item responses, denoted as true item responses, are randomized before observing them and so-called randomized item responses are observed. A relationship is specified between randomized item response data and true item response data. True item response data are modeled with a (non)linear…

  11. Mokken scale analysis of mental health and well-being questionnaire item responses: a non-parametric IRT method in empirical research for applied health researchers

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    Stochl Jan

    2012-06-01

    Full Text Available Abstract Background Mokken scaling techniques are a useful tool for researchers who wish to construct unidimensional tests or use questionnaires that comprise multiple binary or polytomous items. The stochastic cumulative scaling model offered by this approach is ideally suited when the intention is to score an underlying latent trait by simple addition of the item response values. In our experience, the Mokken model appears to be less well-known than for example the (related Rasch model, but is seeing increasing use in contemporary clinical research and public health. Mokken's method is a generalisation of Guttman scaling that can assist in the determination of the dimensionality of tests or scales, and enables consideration of reliability, without reliance on Cronbach's alpha. This paper provides a practical guide to the application and interpretation of this non-parametric item response theory method in empirical research with health and well-being questionnaires. Methods Scalability of data from 1 a cross-sectional health survey (the Scottish Health Education Population Survey and 2 a general population birth cohort study (the National Child Development Study illustrate the method and modeling steps for dichotomous and polytomous items respectively. The questionnaire data analyzed comprise responses to the 12 item General Health Questionnaire, under the binary recoding recommended for screening applications, and the ordinal/polytomous responses to the Warwick-Edinburgh Mental Well-being Scale. Results and conclusions After an initial analysis example in which we select items by phrasing (six positive versus six negatively worded items we show that all items from the 12-item General Health Questionnaire (GHQ-12 – when binary scored – were scalable according to the double monotonicity model, in two short scales comprising six items each (Bech’s “well-being” and “distress” clinical scales. An illustration of ordinal item analysis

  12. Identification of a Semiparametric Item Response Model

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    Peress, Michael

    2012-01-01

    We consider the identification of a semiparametric multidimensional fixed effects item response model. Item response models are typically estimated under parametric assumptions about the shape of the item characteristic curves (ICCs), and existing results suggest difficulties in recovering the distribution of individual characteristics under…

  13. Ramsay-Curve Item Response Theory for the Three-Parameter Logistic Item Response Model

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    Woods, Carol M.

    2008-01-01

    In Ramsay-curve item response theory (RC-IRT), the latent variable distribution is estimated simultaneously with the item parameters of a unidimensional item response model using marginal maximum likelihood estimation. This study evaluates RC-IRT for the three-parameter logistic (3PL) model with comparisons to the normal model and to the empirical…

  14. Extending item response theory to online homework

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    Kortemeyer, Gerd

    2014-06-01

    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 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.

  15. Extending Item Response Theory to Online Homework

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    Kortemeyer, Gerd

    2014-01-01

    Item Response Theory 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 over wide ranges robust with respect to model assumptions and introduced noise, less so than item difficulty.

  16. An Investigation of Multiple-Response-Option Multiple-Choice Items: Item Performance and Processing Demands.

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    Huntley, Renee M.; Plake, Barbara S.

    The combinational-format item (CFI)--multiple-choice item with combinations of alternatives presented as response choices--was studied to determine whether CFIs were different from regular multiple-choice items in item characteristics or in cognitive processing demands. Three undergraduate Foundations of Education classes (consisting of a total of…

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

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    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

  18. Improvement in Detection of Differential Item Functioning Using a Mixture Item Response Theory Model.

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    Maij-de Meij, Annette M; Kelderman, Henk; van der Flier, Henk

    2010-11-30

    Usually, methods for detection of differential item functioning (DIF) compare the functioning of items across manifest groups. However, the manifest groups with respect to which the items function differentially may not necessarily coincide with the true source of the bias. It is expected that DIF detection under a model that includes a latent DIF variable is more sensitive to this source of bias. In a simulation study, it is shown that a mixture item response theory model, which includes a latent grouping variable, performs better in identifying DIF items than DIF detection methods using manifest variables only. The difference between manifest and latent DIF detection increases as the correlation between the manifest variable and the true source of the DIF becomes smaller. Different sample sizes, relative group sizes, and significance levels are studied. Finally, an empirical example demonstrates the detection of heterogeneity in a minority sample using a latent grouping variable. Manifest and latent DIF detection methods are applied to a Vocabulary test of the General Aptitude Test Battery (GATB). PMID:26760725

  19. Analyzing Force Concept Inventory with Item Response Theory

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    Wang, Jing

    2010-01-01

    Item Response Theory (IRT) is a popular assessment method used in education measurement, which builds on an assumption of a probability framework connecting students' innate ability and their actual performances on test items. The model transforms students' raw test scores through a nonlinear regression process into a scaled proficiency rating, which can be used to compare results obtained with different test questions. IRT also provides a theoretical approach to address ceiling effect and guessing. We applied IRT to analyze the Force Concept Inventory (FCI). The data was collected from 2802 students taking intro level mechanics courses at The Ohio State University. The data was analyzed with a 3-parameter item response model for multiple choice questions. We describe the procedures of the analysis and discuss the results and the interpretations. The analysis outcomes are compiled to provide a detailed IRT measurement metric of the FCI, which can be easily referenced and used by teachers and researchers for a...

  20. Evaluation of Anxiety Sensitivity among Daily Adult Smokers using Item Response Theory Analysis

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    Zvolensky, Michael J.; Strong, David; Bernstein, Amit; Vujanovic, Anka A.; Marshall, Erin C.

    2008-01-01

    The present investigation applied Item Response Theory (IRT) methodology to the 16-item Anxiety Sensitivity Index (ASI; Reiss, Peterson, Gursky, & McNally, 1986) for a sample of 475 daily adult smokers (52% women; Mage = 26.9, SD = 11.1, Range = 18 – 65). Using nonparametric item response analysis, all 16 ASI items were evaluated. Evaluation of the Option Characteristic Curves for each item revealed 4 poorly discriminating ASI items (1: “It is important not to appear nervous;” 5: “It is impor...

  1. Stochastic Approximation Methods for Latent Regression Item Response Models

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    von Davier, Matthias; Sinharay, Sandip

    2010-01-01

    This article presents an application of a stochastic approximation expectation maximization (EM) algorithm using a Metropolis-Hastings (MH) sampler to estimate the parameters of an item response latent regression model. Latent regression item response models are extensions of item response theory (IRT) to a latent variable model with covariates…

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

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    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…

  3. An item response curves analysis of the Force Concept Inventory

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    Morris, Gary A.; Harshman, Nathan; Branum-Martin, Lee; Mazur, Eric; Mzoughi, Taha; Baker, Stephen D.

    2012-09-01

    Several years ago, we introduced the idea of item response curves (IRC), a simplistic form of item response theory (IRT), to the physics education research community as a way to examine item performance on diagnostic instruments such as the Force Concept Inventory (FCI). We noted that a full-blown analysis using IRT would be a next logical step, which several authors have since taken. In this paper, we show that our simple approach not only yields similar conclusions in the analysis of the performance of items on the FCI to the more sophisticated and complex IRT analyses but also permits additional insights by characterizing both the correct and incorrect answer choices. Our IRC approach can be applied to a variety of multiple-choice assessments but, as applied to a carefully designed instrument such as the FCI, allows us to probe student understanding as a function of ability level through an examination of each answer choice. We imagine that physics teachers could use IRC analysis to identify prominent misconceptions and tailor their instruction to combat those misconceptions, fulfilling the FCI authors' original intentions for its use. Furthermore, the IRC analysis can assist test designers to improve their assessments by identifying nonfunctioning distractors that can be replaced with distractors attractive to students at various ability levels.

  4. Evaluating Item Discrimination Power of WHOQOL-BREF from an Item Response Model Perspectives

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    Lin, Ting Hsiang; Yao, Grace

    2009-01-01

    Quality of life (QOL) has become an important component of health. By using the methodology of psychometric theory, we examine the item properties of the WHOQOL-BRIEF. Samejima's graded response model with natural metrics of the logistic response function was fitted. The results showed items with negative natures were less discriminating. Items…

  5. Cognitive processes in self-report responses: tests of item context effects in work attitude measures.

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    Harrison, D A; McLaughlin, M E

    1993-02-01

    Much applied research relies on multi-item, self-report instruments. Drawing from recent cognitive theories, it was hypothesized that the items preceding a self-report item, its item context, can generate cognitive carryover and prompt context-consistent responses. These hypotheses were tested in 2 investigations: a field experiment involving 431 employees of a nonprofit urban hospital and a laboratory replication involving 245 undergraduate business students who held full- or part-time jobs. In both studies, evaluatively neutral items were placed in specially arranged blocks of uniformly positive, uniformly negative, or randomly mixed items on 3 modified Job Descriptive Index scales. Responses to the neutral items differed across the 3 forms, but scale-level psychometric properties remained unchanged. The implications of these item- and scale-level results for a variety of self-report measures in organizations are discussed. PMID:8449851

  6. Vegetable parenting practices scale: Item response modeling analyses

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    Our objective was to evaluate the psychometric properties of a vegetable parenting practices scale using multidimensional polytomous item response modeling which enables assessing item fit to latent variables and the distributional characteristics of the items in comparison to the respondents. We al...

  7. An Item Response Model for Characterizing Test Compromise.

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    Segall, Daniel O.

    2002-01-01

    Developed an item response model for characterizing test-compromise that enables the estimation of item preview and score-gain distributions. In the approach, models parameters and posterior distributions are estimated by Markov Chain Monte Carlo procedures. Simulation study results suggest that when at least some test items are known to be…

  8. Comparison of item analysis results of Korean Medical Licensing Examination according to classical test theory and item response theory

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    Eun Young Lim

    2004-01-01

    Full Text Available The results of the 64th and 65th Korean Medical Licensing Examination were analyzed according to the classical test theory and item response theory in order to know the possibility of applying item response theory to item analys and to suggest its applicability to computerized adaptive test. The correlation coefficiency of difficulty index, discriminating index and ability parameter between two kinds of analysis were got using computer programs such as Analyst 4.0, Bilog and Xcalibre. Correlation coefficiencies of difficulty index were equal to or more than 0.75; those of discriminating index were between - 0.023 and 0.753; those of ability parameter were equal to or more than 0.90. Those results suggested that the item analysis according to item response theory showed the comparable results with that according to classical test theory except discriminating index. Since the ability parameter is most widely used in the criteria-reference test, the high correlation between ability parameter and total score can provide the validity of computerized adaptive test utilizing item response theory.

  9. Using response times for item selection in adaptive testing

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    Linden, van der Wim J.

    2008-01-01

    Response times on items can be used to improve item selection in adaptive testing provided that a probabilistic model for their distribution is available. In this research, the author used a hierarchical modeling framework with separate first-level models for the responses and response times and a s

  10. Model-Based Collaborative Filtering Analysis of Student Response Data: Machine-Learning Item Response Theory

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    Bergner, Yoav; Droschler, Stefan; Kortemeyer, Gerd; Rayyan, Saif; Seaton, Daniel; Pritchard, David E.

    2012-01-01

    We apply collaborative filtering (CF) to dichotomously scored student response data (right, wrong, or no interaction), finding optimal parameters for each student and item based on cross-validated prediction accuracy. The approach is naturally suited to comparing different models, both unidimensional and multidimensional in ability, including a…

  11. Generalized Fiducial Inference for Binary Logistic Item Response Models.

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    Liu, Yang; Hannig, Jan

    2016-06-01

    Generalized fiducial inference (GFI) has been proposed as an alternative to likelihood-based and Bayesian inference in mainstream statistics. Confidence intervals (CIs) can be constructed from a fiducial distribution on the parameter space in a fashion similar to those used with a Bayesian posterior distribution. However, no prior distribution needs to be specified, which renders GFI more suitable when no a priori information about model parameters is available. In the current paper, we apply GFI to a family of binary logistic item response theory models, which includes the two-parameter logistic (2PL), bifactor and exploratory item factor models as special cases. Asymptotic properties of the resulting fiducial distribution are discussed. Random draws from the fiducial distribution can be obtained by the proposed Markov chain Monte Carlo sampling algorithm. We investigate the finite-sample performance of our fiducial percentile CI and two commonly used Wald-type CIs associated with maximum likelihood (ML) estimation via Monte Carlo simulation. The use of GFI in high-dimensional exploratory item factor analysis was illustrated by the analysis of a set of the Eysenck Personality Questionnaire data. PMID:26769340

  12. Analysis of Item Response and Differential Item Functioning of Alcohol Expectancies in Middle School Youth

    OpenAIRE

    McCarthy, Denis M.; Pedersen, Sarah L.; D'Amico, Elizabeth J.

    2009-01-01

    Drinking behavior in pre-adolescence is a significant predictor of both short and long-term negative consequences. This study examined the psychometric properties of one known risk factor for drinking in this age group, alcohol expectancies, within an Item Response Theory framework. In a sample of middle school youth (N = 1273), we tested differential item functioning (DIF) in positive and negative alcohol expectancies across grade, gender, and ethnicity. MIMIC model analyses tested differenc...

  13. Obtaining a common scale for item response theory item parameters using separate versus concurrent estimation in the common-item equating design

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    Hanson, Bradley A.; Beguin, Anton A.

    2002-01-01

    Item response theory item parameters can be estimated using data from a common-item equating design either separately for each form or concurrently across forms. This paper reports the results of a simulation study of separate versus concurrent item parameter estimation. Using simulated data from a

  14. A Bayesian Semiparametric Item Response Model with Dirichlet Process Priors

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    Miyazaki, Kei; Hoshino, Takahiro

    2009-01-01

    In Item Response Theory (IRT), item characteristic curves (ICCs) are illustrated through logistic models or normal ogive models, and the probability that examinees give the correct answer is usually a monotonically increasing function of their ability parameters. However, since only limited patterns of shapes can be obtained from logistic models…

  15. More is not Always Better: The Relation between Item Response and Item Response Time in Raven’s Matrices

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    Frank Goldhammer

    2015-03-01

    Full Text Available The role of response time in completing an item can have very different interpretations. Responding more slowly could be positively related to success as the item is answered more carefully. However, the association may be negative if working faster indicates higher ability. The objective of this study was to clarify the validity of each assumption for reasoning items considering the mode of processing. A total of 230 persons completed a computerized version of Raven’s Advanced Progressive Matrices test. Results revealed that response time overall had a negative effect. However, this effect was moderated by items and persons. For easy items and able persons the effect was strongly negative, for difficult items and less able persons it was less negative or even positive. The number of rules involved in a matrix problem proved to explain item difficulty significantly. Most importantly, a positive interaction effect between the number of rules and item response time indicated that the response time effect became less negative with an increasing number of rules. Moreover, exploratory analyses suggested that the error type influenced the response time effect.

  16. Analyzing force concept inventory with item response theory

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    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.

  17. Techniques Applied to the Authentication of Gold Jewellery Items

    International Nuclear Information System (INIS)

    Malleable and ductile, found free in nature, in alluvial deposits as nuggets and pellets, gold could easily be hammered and rolled to form simple objects such as plaques and beads since the Vth millennium BC. The evolution of the goldsmith's skill brought many changes to goldsmithing. Fabricated alloys of required quality and type replaced the natural alloys of gold, were silver and copper are present at rather variable concentrations. A gold alloy could therefore be produced with the colour and the mechanical and physical properties necessary to the final purpose of the item. (author)

  18. Analysis of Item Response and Differential Item Functioning of Alcohol Expectancies in Middle School Youths

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    McCarthy, Denis M.; Pedersen, Sarah L.; D'Amico, Elizabeth J.

    2009-01-01

    Drinking behavior in preadolescence is a significant predictor of both short- and long-term negative consequences. This study examined the psychometric properties of 1 known risk factor for drinking in this age group, alcohol expectancies, within an item response theory framework. In a sample of middle school youths (N = 1,273), the authors tested…

  19. Item response analysis of the inventory of depressive symptomatology

    OpenAIRE

    Bernstein, Ira H.; Rush, A. John; Carmody, Thomas J.; Woo, Ada; Trivedi, Madhukar H

    2006-01-01

    Background: Both the clinician (IDS-C30) and self-report (IDS-SR30) versions of the 30-item Inventory of Depressive Symptomatology have acceptable psychiatric properties and have been used in various clinical studies. These two scales, however, have not been compared using item response theory (IRT) methods to determine whether the standard scoring methods are optimal. Methods: Data were derived from 428 adult public sector outpatients with nonpsychotic major depressive disorder. The IDS-C30 ...

  20. Fighting bias with statistics: Detecting gender differences in responses to items on a preschool science assessment

    Science.gov (United States)

    Greenberg, Ariela Caren

    Differential item functioning (DIF) and differential distractor functioning (DDF) are methods used to screen for item bias (Camilli & Shepard, 1994; Penfield, 2008). Using an applied empirical example, this mixed-methods study examined the congruency and relationship of DIF and DDF methods in screening multiple-choice items. Data for Study I were drawn from item responses of 271 female and 236 male low-income children on a preschool science assessment. Item analyses employed a common statistical approach of the Mantel-Haenszel log-odds ratio (MH-LOR) to detect DIF in dichotomously scored items (Holland & Thayer, 1988), and extended the approach to identify DDF (Penfield, 2008). Findings demonstrated that the using MH-LOR to detect DIF and DDF supported the theoretical relationship that the magnitude and form of DIF and are dependent on the DDF effects, and demonstrated the advantages of studying DIF and DDF in multiple-choice items. A total of 4 items with DIF and DDF and 5 items with only DDF were detected. Study II incorporated an item content review, an important but often overlooked and under-published step of DIF and DDF studies (Camilli & Shepard). Interviews with 25 female and 22 male low-income preschool children and an expert review helped to interpret the DIF and DDF results and their comparison, and determined that a content review process of studied items can reveal reasons for potential item bias that are often congruent with the statistical results. Patterns emerged and are discussed in detail. The quantitative and qualitative analyses were conducted in an applied framework of examining the validity of the preschool science assessment scores for evaluating science programs serving low-income children, however, the techniques can be generalized for use with measures across various disciplines of research.

  1. Item response analysis of the Positive and Negative Syndrome Scale

    Directory of Open Access Journals (Sweden)

    Lindenmayer Jean-Pierre

    2007-11-01

    Full Text Available Abstract Background Statistical models based on item response theory were used to examine (a the performance of individual Positive and Negative Syndrome Scale (PANSS items and their options, (b the effectiveness of various subscales to discriminate among individual differences in symptom severity, and (c the appropriateness of cutoff scores recently recommended by Andreasen and her colleagues (2005 to establish symptom remission. Methods Option characteristic curves were estimated using a nonparametric item response model to examine the probability of endorsing each of 7 options within each of 30 PANSS items as a function of standardized, overall symptom severity. Our data were baseline PANSS scores from 9205 patients with schizophrenia or schizoaffective disorder who were enrolled between 1995 and 2003 in either a large, naturalistic, observational study or else in 1 of 12 randomized, double-blind, clinical trials comparing olanzapine to other antipsychotic drugs. Results Our analyses show that the majority of items forming the Positive and Negative subscales of the PANSS perform very well. We also identified key areas for improvement or revision in items and options within the General Psychopathology subscale. The Positive and Negative subscale scores are not only more discriminating of individual differences in symptom severity than the General Psychopathology subscale score, but are also more efficient on average than the 30-item total score. Of the 8 items recently recommended to establish symptom remission, 1 performed markedly different from the 7 others and should either be deleted or rescored requiring that patients achieve a lower score of 2 (rather than 3 to signal remission. Conclusion This first item response analysis of the PANSS supports its sound psychometric properties; most PANSS items were either very good or good at assessing overall severity of illness. These analyses did identify some items which might be further improved

  2. 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.

  3. An NCME Instructional Module on Latent DIF Analysis Using Mixture Item Response Models

    Science.gov (United States)

    Cho, Sun-Joo; Suh, Youngsuk; Lee, Woo-yeol

    2016-01-01

    The purpose of this ITEMS module is to provide an introduction to differential item functioning (DIF) analysis using mixture item response models. The mixture item response models for DIF analysis involve comparing item profiles across latent groups, instead of manifest groups. First, an overview of DIF analysis based on latent groups, called…

  4. Bad Questions: An Essay Involving Item Response Theory

    Science.gov (United States)

    Thissen, David

    2016-01-01

    David Thissen, a professor in the Department of Psychology and Neuroscience, Quantitative Program at the University of North Carolina, has consulted and served on technical advisory committees for assessment programs that use item response theory (IRT) over the past couple decades. He has come to the conclusion that there are usually two purposes…

  5. Item Response Theory in the context of Improving Student Reasoning

    Science.gov (United States)

    Goddard, Chase; Davis, Jeremy; Pyper, Brian

    2011-10-01

    We are interested to see if Item Response Theory can help to better inform the development of reasoning ability in introductory physics. A first pass through our latest batch of data from the Heat and Temperature Conceptual Evaluation, the Lawson Classroom Test of Scientific Reasoning, and the Epistemological Beliefs About Physics Survey may help in this effort.

  6. Students' Proficiency Scores within Multitrait Item Response Theory

    Science.gov (United States)

    Scott, Terry F.; Schumayer, Daniel

    2015-01-01

    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…

  7. Morphological Contributions to Adolescent Word Reading: An Item Response Approach

    Science.gov (United States)

    Goodwin, Amanda P.; Gilbert, Jennifer K.; Cho, Sun-Joo

    2013-01-01

    The current study uses a crossed random-effects item response model to simultaneously examine both reader and word characteristics and interactions between them that predict the reading of 39 morphologically complex words for 221 middle school students. Results suggest that a reader's ability to read a root word (e.g., "isolate") predicts that…

  8. Reporting of Subscores Using Multidimensional Item Response Theory

    Science.gov (United States)

    Haberman, Shelby J.; Sinharay, Sandip

    2010-01-01

    Recently, there has been increasing interest in reporting subscores. This paper examines reporting of subscores using multidimensional item response theory (MIRT) models (e.g., Reckase in "Appl. Psychol. Meas." 21:25-36, 1997; C.R. Rao and S. Sinharay (Eds), "Handbook of Statistics, vol. 26," pp. 607-642, North-Holland, Amsterdam, 2007; Beguin &…

  9. A Framework for Dimensionality Assessment for Multidimensional Item Response Models

    Science.gov (United States)

    Svetina, Dubravka; Levy, Roy

    2014-01-01

    A framework is introduced for considering dimensionality assessment procedures for multidimensional item response models. The framework characterizes procedures in terms of their confirmatory or exploratory approach, parametric or nonparametric assumptions, and applicability to dichotomous, polytomous, and missing data. Popular and emerging…

  10. Using SAS PROC MCMC for Item Response Theory Models

    Science.gov (United States)

    Ames, Allison J.; Samonte, Kelli

    2015-01-01

    Interest in using Bayesian methods for estimating item response theory models has grown at a remarkable rate in recent years. This attentiveness to Bayesian estimation has also inspired a growth in available software such as WinBUGS, R packages, BMIRT, MPLUS, and SAS PROC MCMC. This article intends to provide an accessible overview of Bayesian…

  11. Minimax D-Optimal Designs for Item Response Theory Models.

    Science.gov (United States)

    Berger, Martjin P. F.; King, C. Y. Joy; Wong, Weng Kee

    2000-01-01

    Proposed minimax designs for item response theory (IRT) models to overcome the problem of local optimality. Compared minimax designs to sequentially constructed designs for the two parameter logistic model. Results show that minimax designs can be nearly as efficient as sequentially constructed designs. (Author/SLD)

  12. Functionally unidimensional item response models for multivariate binary data

    DEFF Research Database (Denmark)

    Ip, Edward; Molenberghs, Geert; Chen, Shyh-Huei;

    2013-01-01

    The problem of fitting unidimensional item response models to potentially multidimensional data has been extensively studied. The focus of this article is on response data that have a strong dimension but also contain minor nuisance dimensions. Fitting a unidimensional model to such multidimensio......The problem of fitting unidimensional item response models to potentially multidimensional data has been extensively studied. The focus of this article is on response data that have a strong dimension but also contain minor nuisance dimensions. Fitting a unidimensional model to such...... 2 issues: (a) can a proposed nonlinear projection track the functional dimension well, and (b) what are the biases in the ability estimate and the associated standard error when estimating the functional dimension? To investigate the second issue, the nonlinear projection is used as an evaluative...

  13. An Item Response Theory Analysis of the Community of Inquiry Scale

    Science.gov (United States)

    Horzum, Mehmet Baris; Uyanik, Gülden Kaya

    2015-01-01

    The aim of this study is to examine validity and reliability of Community of Inquiry Scale commonly used in online learning by the means of Item Response Theory. For this purpose, Community of Inquiry Scale version 14 is applied on 1,499 students of a distance education center's online learning programs at a Turkish state university via internet.…

  14. Using Response Time to Detect Item Preknowledge in Computer-Based Licensure Examinations

    Science.gov (United States)

    Qian, Hong; Staniewska, Dorota; Reckase, Mark; Woo, Ada

    2016-01-01

    This article addresses the issue of how to detect item preknowledge using item response time data in two computer-based large-scale licensure examinations. Item preknowledge is indicated by an unexpected short response time and a correct response. Two samples were used for detecting item preknowledge for each examination. The first sample was from…

  15. Empirical Differences in Omission Tendency and Reading Ability in PISA: An Application of Tree-Based Item Response Models

    Science.gov (United States)

    Okumura, Taichi

    2014-01-01

    This study examined the empirical differences between the tendency to omit items and reading ability by applying tree-based item response (IRTree) models to the Japanese data of the Programme for International Student Assessment (PISA) held in 2009. For this purpose, existing IRTree models were expanded to contain predictors and to handle…

  16. 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.

  17. Item Response Theory with Covariates (IRT-C): Assessing Item Recovery and Differential Item Functioning for the Three-Parameter Logistic Model

    Science.gov (United States)

    Tay, Louis; Huang, Qiming; Vermunt, Jeroen K.

    2016-01-01

    In large-scale testing, the use of multigroup approaches is limited for assessing differential item functioning (DIF) across multiple variables as DIF is examined for each variable separately. In contrast, the item response theory with covariate (IRT-C) procedure can be used to examine DIF across multiple variables (covariates) simultaneously. To…

  18. Network Security Risk Assessment Based on Item Response Theory

    OpenAIRE

    Fangwei Li; Qing Huang; Jiang Zhu; Zhuxun Peng

    2015-01-01

    Owing to the traditional risk assessment method has one-sidedness and is difficult to reflect the real network situation, a risk assessment method based on Item Response Theory (IRT) is put forward in network security. First of all, the novel algorithms of calculating the threat of attack and the successful probability of attack are proposed by the combination of IRT model and Service Security Level. Secondly, the service weight of importance is calculated by the three-demarcation analytic hi...

  19. Evaluating social influence relations: an item-response-modeling approach:

    OpenAIRE

    Schwenk, Gero

    2009-01-01

    Subject of this paper is the measurement of social influence in social networks. The theoretical point of departure is twofold. First, focus is on cognitive processing of perceived influence. Second, three distinct dimensions of social influence are considered: persuasion, authority and coercion. Combining these considerations with Item Response Theory methods, questionnaire-type measurement instruments are proposed. These instruments are employed in a closed network case study where applicab...

  20. An Application of Item Response Theory in the Comparison of Four Conventional Item Discrimination Indices for Criterion-Referenced Tests.

    Science.gov (United States)

    Shannon, Gregory A.; Cliver, Barbara A.

    1987-01-01

    Spearman correlations were computed between item response theory-derived information functions (IIFs) and four conventional item discrimination indices: phi-coefficient; B-index; phi/phi max; and agreement statistic. Correlations between the phi-coefficient and the IIFs were very high. Data were taken from a real estate licensing test. (Author/GDC)

  1. Item Response Theory Analysis and Differential Item Functioning across Age, Gender and Country of a Short Form of the Advanced Progressive Matrices

    Science.gov (United States)

    Chiesi, Francesca; Ciancaleoni, Matteo; Galli, Silvia; Morsanyi, Kinga; Primi, Caterina

    2012-01-01

    Item Response Theory (IRT) models were applied to investigate the psychometric properties of the Arthur and Day's Advanced Progressive Matrices-Short Form (APM-SF; 1994) [Arthur and Day (1994). "Development of a short form for the Raven Advanced Progressive Matrices test." "Educational and Psychological Measurement, 54," 395-403] in order to test…

  2. An investigation of emotional intelligence measures using item response theory.

    Science.gov (United States)

    Cho, Seonghee; Drasgow, Fritz; Cao, Mengyang

    2015-12-01

    This study investigated the psychometric properties of 3 frequently administered emotional intelligence (EI) scales (Wong and Law Emotional Intelligence Scale [WLEIS], Schutte Self-Report Emotional Intelligence Test [SEIT], and Trait Emotional Intelligence Questionnaire [TEIQue]), which were developed on the basis of different theoretical frameworks (i.e., ability EI and mixed EI). By conducting item response theory (IRT) analyses, the authors examined the item parameters and compared the fits of 2 response process models (i.e., dominance model and ideal point model) for these scales with data from 355 undergraduate sample recruited from the subject pool. Several important findings were obtained. First, the EI scales seem better able to differentiate individuals at low trait levels than high trait levels. Second, a dominance model showed better model fit to the self-report ability EI scale (WLEIS) and also fit better with most subfactors of the SEIT, except for the mood regulation/optimism factor. Both dominance and ideal point models fit a self-report mixed EI scale (TEIQue). Our findings suggest (a) the EI scales should be revised to include more items at moderate and higher trait levels; and (b) the nature of the EI construct should be considered during the process of scale development. PMID:25961137

  3. 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. PMID:24033268

  4. Using the Nominal Response Model to Evaluate Response Category Discrimination in the PROMIS Emotional Distress Item Pools

    Science.gov (United States)

    Preston, Kathleen; Reise, Steven; Cai, Li; Hays, Ron D.

    2011-01-01

    The authors used a nominal response item response theory model to estimate category boundary discrimination (CBD) parameters for items drawn from the Emotional Distress item pools (Depression, Anxiety, and Anger) developed in the Patient-Reported Outcomes Measurement Information Systems (PROMIS) project. For polytomous items with ordered response…

  5. 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.

  6. On the Use of Factor-Analytic Multinomial Logit Item Response Models to Account for Individual Differences in Response Style

    Science.gov (United States)

    Johnson, Timothy R.; Bolt, Daniel M.

    2010-01-01

    Multidimensional item response models are usually implemented to model the relationship between item responses and two or more traits of interest. We show how multidimensional multinomial logit item response models can also be used to account for individual differences in response style. This is done by specifying a factor-analytic model for…

  7. Analysis of Multiple Partially Ordered Responses to Belief Items with Don't Know Option.

    Science.gov (United States)

    Ip, Edward H; Chen, Shyh-Huei; Quandt, Sara A

    2016-06-01

    Understanding beliefs, values, and preferences of patients is a tenet of contemporary health sciences. This application was motivated by the analysis of multiple partially ordered set (poset) responses from an inventory on layman beliefs about diabetes. The partially ordered set arises because of two features in the data-first, the response options contain a Don't Know (DK) option, and second, there were two consecutive occasions of measurement. As predicted by the common sense model of illness, beliefs about diabetes were not necessarily stable across the two measurement occasions. Instead of analyzing the two occasions separately, we studied the joint responses across the occasions as a poset response. Few analytic methods exist for data structures other than ordered or nominal categories. Poset responses are routinely collapsed and then analyzed as either rank ordered or nominal data, leading to the loss of nuanced information that might be present within poset categories. In this paper we developed a general class of item response models for analyzing the poset data collected from the Common Sense Model of Diabetes Inventory. The inferential object of interest is the latent trait that indicates congruence of belief with the biomedical model. To apply an item response model to the poset diabetes inventory, we proved that a simple coding algorithm circumvents the requirement of writing new codes such that standard IRT software could be directly used for the purpose of item estimation and individual scoring. Simulation experiments were used to examine parameter recovery for the proposed poset model. PMID:25479822

  8. An Item Response Theory Analysis of the Community of Inquiry Scale

    Directory of Open Access Journals (Sweden)

    Mehmet Barış Horzum

    2015-04-01

    Full Text Available The aim of this study is to examine validity and reliability of Community of Inquiry Scale commonly used in online learning by the means of Item Response Theory. For this purpose, Community of Inquiry Scale version 14 is applied on 1,499 students of a distance education center’s online learning programs at a Turkish state university via internet. The collected data is analyzed by using a statistical software package. Research data is analyzed in three aspects, which are checking model assumptions, checking model-data fit and item analysis. Item and test features of the scale are examined by the means of Graded Response Theory. In order to use this model of IRT, after testing the assumptions out of the data gathered from 1,499 participants, data model compliance was examined. Following the affirmative results gathered from the examinations, all data is analyzed by using GRM. As a result of the study, the Community of Inquiry Scale adapted to Turkish by Horzum (in press is found to be reliable and valid by the means of Classical Test Theory and Item Response Theory.

  9. Reevaluation of the Amsterdam Inventory for Auditory Disability and Handicap Using Item Response Theory

    Science.gov (United States)

    Hospers, J. Mirjam Boeschen; Smits, Niels; Smits, Cas; Stam, Mariska; Terwee, Caroline B.; Kramer, Sophia E.

    2016-01-01

    Purpose: We reevaluated the psychometric properties of the Amsterdam Inventory for Auditory Disability and Handicap (AIADH; Kramer, Kapteyn, Festen, & Tobi, 1995) using item response theory. Item response theory describes item functioning along an ability continuum. Method: Cross-sectional data from 2,352 adults with and without hearing…

  10. Limits on Log Odds Ratios for Unidimensional Item Response Theory Models

    Science.gov (United States)

    Haberman, Shelby J.; Holland, Paul W.; Sinharay, Sandip

    2007-01-01

    Bounds are established for log odds ratios (log cross-product ratios) involving pairs of items for item response models. First, expressions for bounds on log odds ratios are provided for one-dimensional item response models in general. Then, explicit bounds are obtained for the Rasch model and the two-parameter logistic (2PL) model. Results are…

  11. Analysis of differential item functioning in the depression item bank from the Patient Reported Outcome Measurement Information System (PROMIS: An item response theory approach

    Directory of Open Access Journals (Sweden)

    JOSEPH P. EIMICKE

    2009-06-01

    Full Text Available The aims of this paper are to present findings related to differential item functioning (DIF in the Patient Reported Outcome Measurement Information System (PROMIS depression item bank, and to discuss potential threats to the validity of results from studies of DIF. The 32 depression items studied were modified from several widely used instruments. DIF analyses of gender, age and education were performed using a sample of 735 individuals recruited by a survey polling firm. DIF hypotheses were generated by asking content experts to indicate whether or not they expected DIF to be present, and the direction of the DIF with respect to the studied comparison groups. Primary analyses were conducted using the graded item response model (for polytomous, ordered response category data with likelihood ratio tests of DIF, accompanied by magnitude measures. Sensitivity analyses were performed using other item response models and approaches to DIF detection. Despite some caveats, the items that are recommended for exclusion or for separate calibration were "I felt like crying" and "I had trouble enjoying things that I used to enjoy." The item, "I felt I had no energy," was also flagged as evidencing DIF, and recommended for additional review. On the one hand, false DIF detection (Type 1 error was controlled to the extent possible by ensuring model fit and purification. On the other hand, power for DIF detection might have been compromised by several factors, including sparse data and small sample sizes. Nonetheless, practical and not just statistical significance should be considered. In this case the overall magnitude and impact of DIF was small for the groups studied, although impact was relatively large for some individuals.

  12. lordif: An R Package for Detecting Differential Item Functioning Using Iterative Hybrid Ordinal Logistic Regression/Item Response Theory and Monte Carlo Simulations

    Directory of Open Access Journals (Sweden)

    Seung W. Choi

    2011-03-01

    Full Text Available Logistic regression provides a flexible framework for detecting various types of differential item functioning (DIF. Previous efforts extended the framework by using item response theory (IRT based trait scores, and by employing an iterative process using group--specific item parameters to account for DIF in the trait scores, analogous to purification approaches used in other DIF detection frameworks. The current investigation advances the technique by developing a computational platform integrating both statistical and IRT procedures into a single program. Furthermore, a Monte Carlo simulation approach was incorporated to derive empirical criteria for various DIF statistics and effect size measures. For purposes of illustration, the procedure was applied to data from a questionnaire of anxiety symptoms for detecting DIF associated with age from the Patient--Reported Outcomes Measurement Information System.

  13. Self efficacy for fruit, vegetable and water intakes: Expanded and abbreviated scales from item response modeling analyses

    Directory of Open Access Journals (Sweden)

    Cullen Karen W

    2010-03-01

    Full Text Available Abstract Objective To improve an existing measure of fruit and vegetable intake self efficacy by including items that varied on levels of difficulty, and testing a corresponding measure of water intake self efficacy. Design Cross sectional assessment. Items were modified to have easy, moderate and difficult levels of self efficacy. Classical test theory and item response modeling were applied. Setting One middle school at each of seven participating sites (Houston TX, Irvine CA, Philadelphia PA, Pittsburg PA, Portland OR, rural NC, and San Antonio TX. Subjects 714 6th grade students. Results Adding items to reflect level (low, medium, high of self efficacy for fruit and vegetable intake achieved scale reliability and validity comparable to existing scales, but the distribution of items across the latent variable did not improve. Selecting items from among clusters of items at similar levels of difficulty along the latent variable resulted in an abbreviated scale with psychometric characteristics comparable to the full scale, except for reliability. Conclusions The abbreviated scale can reduce participant burden. Additional research is necessary to generate items that better distribute across the latent variable. Additional items may need to tap confidence in overcoming more diverse barriers to dietary intake.

  14. Statistical Tests of Conditional Independence between Responses and/or Response Times on Test Items

    Science.gov (United States)

    van der Linden, Wim J.; Glas, Cees A. W.

    2010-01-01

    Three plausible assumptions of conditional independence in a hierarchical model for responses and response times on test items are identified. For each of the assumptions, a Lagrange multiplier test of the null hypothesis of conditional independence against a parametric alternative is derived. The tests have closed-form statistics that are easy to…

  15. A Pearson-Type-VII Item Response Model for Assessing Person Fluctuation

    Science.gov (United States)

    Ferrando, Pere J.

    2007-01-01

    Using Lumsden's Thurstonian fluctuation model as a starting point, this paper attempts to develop a unidimensional item response theory model intended for binary personality items. Under some additional assumptions, a new model is obtained in which the item characteristic curves are defined by a cumulative Pearson-Type-VII distribution, and the…

  16. A Comparison of Item Parameter Standard Error Estimation Procedures for Unidimensional and Multidimensional Item Response Theory Modeling

    Science.gov (United States)

    Paek, Insu; Cai, Li

    2014-01-01

    The present study was motivated by the recognition that standard errors (SEs) of item response theory (IRT) model parameters are often of immediate interest to practitioners and that there is currently a lack of comparative research on different SE (or error variance-covariance matrix) estimation procedures. The present study investigated item…

  17. Item response theory and the measurement of psychiatric constructs: some empirical and conceptual issues and challenges.

    Science.gov (United States)

    Reise, S P; Rodriguez, A

    2016-07-01

    Item response theory (IRT) measurement models are now commonly used in educational, psychological, and health-outcomes measurement, but their impact in the evaluation of measures of psychiatric constructs remains limited. Herein we present two, somewhat contradictory, theses. The first is that, when skillfully applied, IRT has much to offer psychiatric measurement in terms of scale development, psychometric analysis, and scoring. The second argument, however, is that psychiatric measurement presents some unique challenges to the application of IRT - challenges that may not be easily addressed by application of conventional IRT models and methods. These challenges include, but are not limited to, the modeling of conceptually narrow constructs and their associated limited item pools, and unipolar constructs where the expected latent trait distribution is highly skewed. PMID:27056796

  18. Adult Attachment Ratings (AAR): An Item Response Theory Analysis

    OpenAIRE

    Pilkonis, Paul A.; Kim, Yookyung; Yu, Lan; Morse, Jennifer Q.

    2013-01-01

    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 resp...

  19. An Item Response Theory Analysis of the Community of Inquiry Scale

    OpenAIRE

    Mehmet Barış Horzum; Gülden Kaya Uyanık

    2015-01-01

    The aim of this study is to examine validity and reliability of Community of Inquiry Scale commonly used in online learning by the means of Item Response Theory. For this purpose, Community of Inquiry Scale version 14 is applied on 1,499 students of a distance education center’s online learning programs at a Turkish state university via internet. The collected data is analyzed by using a statistical software package. Research data is analyzed in three aspects, which are checking model assumpt...

  20. Dimensionality of the UWES-17: An item response modelling analysis

    Directory of Open Access Journals (Sweden)

    Deon P. de Bruin

    2013-03-01

    Full Text Available Orientation: Questionnaires, particularly the Utrecht Work Engagement Scale (UWES-17, are an almost standard method by which to measure work engagement. Conflicting evidence regarding the dimensionality of the UWES-17 has led to confusion regarding the interpretation of scores.Research purpose: The main focus of this study was to use the Rasch model to provide insight into the dimensionality of the UWES-17, and to assess whether work engagement should be interpreted as one single overall score, three separate scores, or a combination.Motivation for the study: It is unclear whether a summative score is more representative of work engagement or whether scores are more meaningful when interpreted for each dimension separately. Previous work relied on confirmatory factor analysis; the potential of item response models has not been tapped.Research design: A quantitative cross-sectional survey design approach was used. Participants, 2429 employees of a South African Information and Communication Technology (ICT company, completed the UWES-17.Main findings: Findings indicate that work engagement should be treated as a unidimensional construct: individual scores should be interpreted in a summative manner, giving a single global score.Practical/managerial implications: Users of the UWES-17 may interpret a single, summative score for work engagement. Findings of this study should also contribute towards standardising UWES-17 scores, allowing meaningful comparisons to be made.Contribution/value-add: The findings will benefit researchers, organisational consultants and managers. Clarity on dimensionality and interpretation of work engagement will assist researchers in future studies. Managers and consultants will be able to make better-informed decisions when using work engagement data.

  1. Difference in method of administration did not significantly impact item response

    DEFF Research Database (Denmark)

    Bjorner, Jakob B; Rose, Matthias; Gandek, Barbara;

    2014-01-01

    PURPOSE: To test the impact of method of administration (MOA) on the measurement characteristics of items developed in the Patient-Reported Outcomes Measurement Information System (PROMIS). METHODS: Two non-overlapping parallel 8-item forms from each of three PROMIS domains (physical function...... assistant (PDA), or personal computer (PC) on the Internet, and a second form by PC, in the same administration. Structural invariance, equivalence of item responses, and measurement precision were evaluated using confirmatory factor analysis and item response theory methods. RESULTS: Multigroup...... confirmatory factor analysis supported equivalence of factor structure across MOA. Analyses by item response theory found no differences in item location parameters and strongly supported the equivalence of scores across MOA. CONCLUSIONS: We found no statistically or clinically significant differences in score...

  2. Item response theory-based measure of global disability in multiple sclerosis derived from the Performance Scales and related items

    OpenAIRE

    Chamot, Eric; Kister, Ilya; Cutter, Gary R.

    2014-01-01

    Background The eight Performance Scales and three assimilated scales (PS) used in North American Research Committee on Multiple Sclerosis (NARCOMS) registry surveys cover a broad range of neurologic domains commonly affected by multiple sclerosis (mobility, hand function, vision, fatigue, cognition, bladder/bowel, sensory, spasticity, pain, depression, and tremor/coordination). Each scale consists of a single 6-to-7-point Likert item with response categories ranging from “normal” to “total di...

  3. Stochastic Approximation Methods for Latent Regression Item Response Models. Research Report. ETS RR-09-09

    Science.gov (United States)

    von Davier, Matthias; Sinharay, Sandip

    2009-01-01

    This paper presents an application of a stochastic approximation EM-algorithm using a Metropolis-Hastings sampler to estimate the parameters of an item response latent regression model. Latent regression models are extensions of item response theory (IRT) to a 2-level latent variable model in which covariates serve as predictors of the…

  4. IRTPRO 2.1 for Windows (Item Response Theory for Patient-Reported Outcomes)

    Science.gov (United States)

    Paek, Insu; Han, Kyung T.

    2013-01-01

    This article reviews a new item response theory (IRT) model estimation program, IRTPRO 2.1, for Windows that is capable of unidimensional and multidimensional IRT model estimation for existing and user-specified constrained IRT models for dichotomously and polytomously scored item response data. (Contains 1 figure and 2 notes.)

  5. Secondary Psychometric Examination of the Dimensional Obsessive-Compulsive Scale: Classical Testing, Item Response Theory, and Differential Item Functioning.

    Science.gov (United States)

    Thibodeau, Michel A; Leonard, Rachel C; Abramowitz, Jonathan S; Riemann, Bradley C

    2015-12-01

    The Dimensional Obsessive-Compulsive Scale (DOCS) is a promising measure of obsessive-compulsive disorder (OCD) symptoms but has received minimal psychometric attention. We evaluated the utility and reliability of DOCS scores. The study included 832 students and 300 patients with OCD. Confirmatory factor analysis supported the originally proposed four-factor structure. DOCS total and subscale scores exhibited good to excellent internal consistency in both samples (α = .82 to α = .96). Patient DOCS total scores reduced substantially during treatment (t = 16.01, d = 1.02). DOCS total scores discriminated between students and patients (sensitivity = 0.76, 1 - specificity = 0.23). The measure did not exhibit gender-based differential item functioning as tested by Mantel-Haenszel chi-square tests. Expected response options for each item were plotted as a function of item response theory and demonstrated that DOCS scores incrementally discriminate OCD symptoms ranging from low to extremely high severity. Incremental differences in DOCS scores appear to represent unbiased and reliable differences in true OCD symptom severity. PMID:25422521

  6. Efficiently Assessing Negative Cognition in Depression: An Item Response Theory Analysis of the Dysfunctional Attitude Scale

    Science.gov (United States)

    Beevers, Christopher G.; Strong, David R.; Meyer, Bjorn; Pilkonis, Paul A.; Miller, Ivan R.

    2007-01-01

    Despite a central role for dysfunctional attitudes in cognitive theories of depression and the widespread use of the Dysfunctional Attitude Scale, form A (DAS-A; A. Weissman, 1979), the psychometric development of the DAS-A has been relatively limited. The authors used nonparametric item response theory methods to examine the DAS-A items and…

  7. An NCME Instructional Module on Estimating Item Response Theory Models Using Markov Chain Monte Carlo Methods

    Science.gov (United States)

    Kim, Jee-Seon; Bolt, Daniel M.

    2007-01-01

    The purpose of this ITEMS module is to provide an introduction to Markov chain Monte Carlo (MCMC) estimation for item response models. A brief description of Bayesian inference is followed by an overview of the various facets of MCMC algorithms, including discussion of prior specification, sampling procedures, and methods for evaluating chain…

  8. Use of NON-PARAMETRIC Item Response Theory to develop a shortened version of the Positive and Negative Syndrome Scale (PANSS

    Directory of Open Access Journals (Sweden)

    Khan Anzalee

    2011-11-01

    Full Text Available Abstract Background Nonparametric item response theory (IRT was used to examine (a the performance of the 30 Positive and Negative Syndrome Scale (PANSS items and their options ((levels of severity, (b the effectiveness of various subscales to discriminate among differences in symptom severity, and (c the development of an abbreviated PANSS (Mini-PANSS based on IRT and a method to link scores to the original PANSS. Methods Baseline PANSS scores from 7,187 patients with Schizophrenia or Schizoaffective disorder who were enrolled between 1995 and 2005 in psychopharmacology trials were obtained. Option characteristic curves (OCCs and Item Characteristic Curves (ICCs were constructed to examine the probability of rating each of seven options within each of 30 PANSS items as a function of subscale severity, and summed-score linking was applied to items selected for the Mini-PANSS. Results The majority of items forming the Positive and Negative subscales (i.e. 19 items performed very well and discriminate better along symptom severity compared to the General Psychopathology subscale. Six of the seven Positive Symptom items, six of the seven Negative Symptom items, and seven out of the 16 General Psychopathology items were retained for inclusion in the Mini-PANSS. Summed score linking and linear interpolation was able to produce a translation table for comparing total subscale scores of the Mini-PANSS to total subscale scores on the original PANSS. Results show scores on the subscales of the Mini-PANSS can be linked to scores on the original PANSS subscales, with very little bias. Conclusions The study demonstrated the utility of non-parametric IRT in examining the item properties of the PANSS and to allow selection of items for an abbreviated PANSS scale. The comparisons between the 30-item PANSS and the Mini-PANSS revealed that the shorter version is comparable to the 30-item PANSS, but when applying IRT, the Mini-PANSS is also a good indicator of

  9. Origin of the Scaling Constant "d" = 1.7 in Item Response Theory.

    Science.gov (United States)

    Camilli, Gregory

    1994-01-01

    Describes the scaling constant "d" = 1.702, used in Item Response Theory, which minimizes the maximum difference between the normal and logistic distribution functions. Recapitulates the theoretical and numerical derivation of "d" given by D. Haley (1952). (SLD)

  10. Numerical Differentiation Methods for Computing Error Covariance Matrices in Item Response Theory Modeling: An Evaluation and a New Proposal

    Science.gov (United States)

    Tian, Wei; Cai, Li; Thissen, David; Xin, Tao

    2013-01-01

    In item response theory (IRT) modeling, the item parameter error covariance matrix plays a critical role in statistical inference procedures. When item parameters are estimated using the EM algorithm, the parameter error covariance matrix is not an automatic by-product of item calibration. Cai proposed the use of Supplemented EM algorithm for…

  11. Item Response Theory Analyses of the Cambridge Face Memory Test (CFMT)

    OpenAIRE

    Cho, Sun-Joo; Wilmer, Jeremy; Herzmann, Grit; McGugin, Rankin; Fiset, Daniel; Van Gulick, Ana E.; Ryan, Katie; Gauthier, Isabel

    2015-01-01

    We evaluated the psychometric properties of the Cambridge face memory test (CFMT; Duchaine & Nakayama, 2006). First, we assessed the dimensionality of the test with a bi-factor exploratory factor analysis (EFA). This EFA analysis revealed a general factor and three specific factors clustered by targets of CFMT. However, the three specific factors appeared to be minor factors that can be ignored. Second, we fit a unidimensional item response model. This item response model showed that the CFMT...

  12. 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.

  13. How Item Response Theory can solve problems of ipsative data

    OpenAIRE

    Brown, Anna

    2010-01-01

    [eng] Multidimensional forced-choice questionnaires can reduce the impact of numerous response biases typically associated with Likert scales. However, if scored with traditional methodology these instruments produce ipsative data, which has psychometric problems, such as constrained total test score and negative average scale inter-correlation. Ipsative scores distort scale relationships and reliability estimates, and make interpretation of scores problematic. This research demonstrates how ...

  14. Model Choice and Sample Size in Item Response Theory Analysis of Aphasia Tests

    Science.gov (United States)

    Hula, William D.; Fergadiotis, Gerasimos; Martin, Nadine

    2012-01-01

    Purpose: The purpose of this study was to identify the most appropriate item response theory (IRT) measurement model for aphasia tests requiring 2-choice responses and to determine whether small samples are adequate for estimating such models. Method: Pyramids and Palm Trees (Howard & Patterson, 1992) test data that had been collected from…

  15. Harmonization of Neuroticism and Extraversion phenotypes across inventories and cohorts in the Genetics of Personality Consortium: an application of Item Response Theory

    DEFF Research Database (Denmark)

    van den Berg, S. M.; de Moor, M. H. M.; McGue, Matt;

    2014-01-01

    -analyses can be employed. Within the Genetics of Personality Consortium, we demonstrate for two clinically relevant personality traits, Neuroticism and Extraversion, how Item-Response Theory (IRT) can be applied to map item data from different inventories to the same underlying constructs. Personality item...... data were analyzed in > 160,000 individuals from 23 cohorts across Europe, USA and Australia in which Neuroticism and Extraversion were assessed by nine different personality inventories. Results showed that harmonization was very successful for most personality inventories and moderately successful...

  16. Development and Standardization of the Diagnostic Adaptive Behavior Scale: Application of Item Response Theory to the Assessment of Adaptive Behavior

    Science.gov (United States)

    Tassé, Marc J.; Schalock, Robert L.; Thissen, David; Balboni, Giulia; Bersani, Henry, Jr.; Borthwick-Duffy, Sharon A.; Spreat, Scott; Widaman, Keith F.; Zhang, Dalun; Navas, Patricia

    2016-01-01

    The Diagnostic Adaptive Behavior Scale (DABS) was developed using item response theory (IRT) methods and was constructed to provide the most precise and valid adaptive behavior information at or near the cutoff point of making a decision regarding a diagnosis of intellectual disability. The DABS initial item pool consisted of 260 items. Using IRT…

  17. Computer Response Time Measurements of Mood, Fatigue and Symptom Scale Items: Implications for Scale Response Time Uses.

    Science.gov (United States)

    Ryman, David H.; And Others

    1988-01-01

    Describes study conducted with U.S. Marine Corps enlisted personnel to measure response time to computer-administered questionnaire items, and to evaluate how measurement of response time might be useful in various research areas. Topics addressed include mood states; the occurrence of straight lining; and experimental effects of sleep loss and…

  18. Modeling Polytomous Item Responses Using Simultaneously Estimated Multinomial Logistic Regression Models

    Science.gov (United States)

    Anderson, Carolyn J.; Verkuilen, Jay; Peyton, Buddy L.

    2010-01-01

    Survey items with multiple response categories and multiple-choice test questions are ubiquitous in psychological and educational research. We illustrate the use of log-multiplicative association (LMA) models that are extensions of the well-known multinomial logistic regression model for multiple dependent outcome variables to reanalyze a set of…

  19. Item Response Theory with Estimation of the Latent Population Distribution Using Spline-Based Densities

    Science.gov (United States)

    Woods, Carol M.; Thissen, David

    2006-01-01

    The purpose of this paper is to introduce a new method for fitting item response theory models with the latent population distribution estimated from the data using splines. A spline-based density estimation system provides a flexible alternative to existing procedures that use a normal distribution, or a different functional form, for the…

  20. The Value of Item Response Theory in Clinical Assessment: A Review

    Science.gov (United States)

    Thomas, Michael L.

    2011-01-01

    Item response theory (IRT) and related latent variable models represent modern psychometric theory, the successor to classical test theory in psychological assessment. Although IRT has become prevalent in the measurement of ability and achievement, its contributions to clinical domains have been less extensive. Applications of IRT to clinical…

  1. The Shortened Raven Standard Progressive Matrices: Item Response Theory-Based Psychometric Analyses and Normative Data

    Science.gov (United States)

    Van der Elst, Wim; Ouwehand, Carolijn; van Rijn, Peter; Lee, Nikki; Van Boxtel, Martin; Jolles, Jelle

    2013-01-01

    The purpose of the present study was to evaluate the psychometric properties of a shortened version of the Raven Standard Progressive Matrices (SPM) under an item response theory framework (the one- and two-parameter logistic models). The shortened Raven SPM was administered to N = 453 cognitively healthy adults aged between 24 and 83 years. The…

  2. Discussion of David Thissen's Bad Questions: An Essay Involving Item Response Theory

    Science.gov (United States)

    Wainer, Howard

    2016-01-01

    The usual role of a discussant is to clarify and correct the paper being discussed, but in this case, the author, Howard Wainer, generally agrees with everything David Thissen says in his essay, "Bad Questions: An Essay Involving Item Response Theory." This essay expands on David Thissen's statement that there are typically two principal…

  3. Three Essays on Teacher Education Programs and Test-Takers' Response Times on Test Items

    Science.gov (United States)

    Qian, Hong

    2013-01-01

    This dissertation includes three essays: one essay focuses on the effect of teacher preparation programs on teacher knowledge while the other two focus on test-takers' response times on test items. Essay One addresses the problem of how opportunities to learn in teacher preparation programs influence future elementary mathematics teachers'…

  4. How Often Is the Misfit of Item Response Theory Models Practically Significant?

    Science.gov (United States)

    Sinharay, Sandip; Haberman, Shelby J.

    2014-01-01

    Standard 3.9 of the Standards for Educational and Psychological Testing ([, 1999]) demands evidence of model fit when item response theory (IRT) models are employed to data from tests. Hambleton and Han ([Hambleton, R. K., 2005]) and Sinharay ([Sinharay, S., 2005]) recommended the assessment of practical significance of misfit of IRT models, but…

  5. An Introduction to Item Response Theory and Rasch Models for Speech-Language Pathologists

    Science.gov (United States)

    Baylor, Carolyn; Hula, William; Donovan, Neila J.; Doyle, Patrick J.; Kendall, Diane; Yorkston, Kathryn

    2011-01-01

    Purpose: To present a primarily conceptual introduction to item response theory (IRT) and Rasch models for speech-language pathologists (SLPs). Method: This tutorial introduces SLPs to basic concepts and terminology related to IRT as well as the most common IRT models. The article then continues with an overview of how instruments are developed…

  6. Measuring Integration of Information and Communication Technology in Education: An Item Response Modeling Approach

    Science.gov (United States)

    Peeraer, Jef; Van Petegem, Peter

    2012-01-01

    This research describes the development and validation of an instrument to measure integration of Information and Communication Technology (ICT) in education. After literature research on definitions of integration of ICT in education, a comparison is made between the classical test theory and the item response modeling approach for the…

  7. D-Optimal Sequential Sampling Designs for Item Response Theory Models.

    Science.gov (United States)

    Berger, Martijn P. F.

    1994-01-01

    Problems in selection of optimal designs in item-response theory (IRT) models are resolved through a sequential design procedure that is a modification of the D-optimality procedure proposed by Wynn (1970). This algorithm leads to consistent estimates, and the errors in selecting the abilities generally do not greatly affect optimality. (SLD)

  8. Mokken scale analysis : Between the Guttman scale and parametric item response theory

    NARCIS (Netherlands)

    van Schuur, Wijbrandt H.

    2003-01-01

    This article introduces a model of ordinal unidimensional measurement known as Mokken scale analysis. Mokken scaling is based on principles of Item Response Theory (IRT) that originated in the Guttman scale. I compare the Mokken model with both Classical Test Theory (reliability or factor analysis)

  9. Using Item Response Theory to Assess Changes in Student Performance Based on Changes in Question Wording

    Science.gov (United States)

    Schurmeier, Kimberly D.; Atwood, Charles H.; Shepler, Carrie G.; Lautenschlager, Gary J.

    2010-01-01

    Five years of longitudinal data for general chemistry student assessments at the University of Georgia have been analyzed using item response theory (IRT). Our analysis indicates that minor changes in question wording on exams can make significant differences in student performance on assessment questions. This analysis encompasses data from over…

  10. The Impact of Outliers on Cronbach's Coefficient Alpha Estimate of Reliability: Ordinal/Rating Scale Item Responses

    Science.gov (United States)

    Liu, Yan; Wu, Amery D.; Zumbo, Bruno D.

    2010-01-01

    In a recent Monte Carlo simulation study, Liu and Zumbo showed that outliers can severely inflate the estimates of Cronbach's coefficient alpha for continuous item response data--visual analogue response format. Little, however, is known about the effect of outliers for ordinal item response data--also commonly referred to as Likert, Likert-type,…

  11. A modular approach for item response theory modeling with the R package flirt.

    Science.gov (United States)

    Jeon, Minjeong; Rijmen, Frank

    2016-06-01

    The new R package flirt is introduced for flexible item response theory (IRT) modeling of psychological, educational, and behavior assessment data. flirt integrates a generalized linear and nonlinear mixed modeling framework with graphical model theory. The graphical model framework allows for efficient maximum likelihood estimation. The key feature of flirt is its modular approach to facilitate convenient and flexible model specifications. Researchers can construct customized IRT models by simply selecting various modeling modules, such as parametric forms, number of dimensions, item and person covariates, person groups, link functions, etc. In this paper, we describe major features of flirt and provide examples to illustrate how flirt works in practice. PMID:26174711

  12. Modeling the World Health Organization Disability Assessment Schedule II using non-parametric item response models.

    Science.gov (United States)

    Galindo-Garre, Francisca; Hidalgo, María Dolores; Guilera, Georgina; Pino, Oscar; Rojo, J Emilio; Gómez-Benito, Juana

    2015-03-01

    The World Health Organization Disability Assessment Schedule II (WHO-DAS II) is a multidimensional instrument developed for measuring disability. It comprises six domains (getting around, self-care, getting along with others, life activities and participation in society). The main purpose of this paper is the evaluation of the psychometric properties for each domain of the WHO-DAS II with parametric and non-parametric Item Response Theory (IRT) models. A secondary objective is to assess whether the WHO-DAS II items within each domain form a hierarchy of invariantly ordered severity indicators of disability. A sample of 352 patients with a schizophrenia spectrum disorder is used in this study. The 36 items WHO-DAS II was administered during the consultation. Partial Credit and Mokken scale models are used to study the psychometric properties of the questionnaire. The psychometric properties of the WHO-DAS II scale are satisfactory for all the domains. However, we identify a few items that do not discriminate satisfactorily between different levels of disability and cannot be invariantly ordered in the scale. In conclusion the WHO-DAS II can be used to assess overall disability in patients with schizophrenia, but some domains are too general to assess functionality in these patients because they contain items that are not applicable to this pathology. PMID:25524862

  13. Fit of Item Response Theory Models: A Survey of Data from Several Operational Tests. Research Report. ETS RR-11-29

    Science.gov (United States)

    Sinharay, Sandip; Haberman, Shelby J.; Jia, Helena

    2011-01-01

    Standard 3.9 of the "Standards for Educational and Psychological Testing" (American Educational Research Association, American Psychological Association, & National Council for Measurement in Education, 1999) demands evidence of model fit when an item response theory (IRT) model is used to make inferences from a data set. We applied two recently…

  14. 单维项目因素分析:CCFA与IRT估计方法的比较%Unidimensional Item Factor Analysis: A Comparison of Categorical Confirmation Factor Analysis and the Item Response Theory

    Institute of Scientific and Technical Information of China (English)

    刘红云; 李美娟; 骆方; 李小山

    2012-01-01

    item factor load and of item discrimination parameter was influenced by the size of the whole factor load (discrimination). (5) The distribution of the threshold of test item affected the precision of the parameter estimate, and item discrimination was the most sensitive parameter to the threshold. (6) On the whole, the precision of item parameter estimate in SEM framework was higher than that in IRT framework. Both structural equation modeling (SEM) and the item response theory (IRT) could be used for factor analysis of dichotomous item responses. In this case, the measurement models of both approaches were formally equivalent. They were refined within and across different disciplines, and made complementary contributions to central measurement problems encountered in almost all empirical social science research fields. The authors concluded with considerations for categorical item factor analysis and gave some advice for applied researchers.

  15. Estimating Ordinal Reliability for Likert-Type and Ordinal Item Response Data: A Conceptual, Empirical, and Practical Guide

    Science.gov (United States)

    Gadermann, Anne M.; Guhn, Martin; Zumbo, Bruno D.

    2012-01-01

    This paper provides a conceptual, empirical, and practical guide for estimating ordinal reliability coefficients for ordinal item response data (also referred to as Likert, Likert-type, ordered categorical, or rating scale item responses). Conventionally, reliability coefficients, such as Cronbach's alpha, are calculated using a Pearson…

  16. On the Relationship between Classical Test Theory and Item Response Theory: From One to the Other and Back

    Science.gov (United States)

    Raykov, Tenko; Marcoulides, George A.

    2016-01-01

    The frequently neglected and often misunderstood relationship between classical test theory and item response theory is discussed for the unidimensional case with binary measures and no guessing. It is pointed out that popular item response models can be directly obtained from classical test theory-based models by accounting for the discrete…

  17. An evaluation of the Brief Symptom Inventory-18 using item response theory: which items are most strongly related to psychological distress?

    NARCIS (Netherlands)

    Meijer, Rob R.; Vries, de Rivka M.; Bruggen, van Vincent

    2011-01-01

    The psychometric structure of the Brief Symptom Inventory–18 (BSI-18; Derogatis, 2001) was investigated using Mokken scaling and parametric item response theory. Data of 487 outpatients, 266 students, and 207 prisoners were analyzed. Results of the Mokken analysis indicated that the BSI-18 formed a

  18. An Evaluation of the Brief Symptom Inventory-18 Using Item Response Theory: Which Items Are Most Strongly Related to Psychological Distress?

    Science.gov (United States)

    Meijer, Rob R.; de Vries, Rivka M.; van Bruggen, Vincent

    2011-01-01

    The psychometric structure of the Brief Symptom Inventory-18 (BSI-18; Derogatis, 2001) was investigated using Mokken scaling and parametric item response theory. Data of 487 outpatients, 266 students, and 207 prisoners were analyzed. Results of the Mokken analysis indicated that the BSI-18 formed a strong Mokken scale for outpatients and…

  19. An Evaluation of the Brief Symptom Inventory-18 Using Item Response Theory : Which Items Are Most Strongly Related to Psychological Distress?

    NARCIS (Netherlands)

    Meijer, Rob R.; de Vries, Rivka M.; van Bruggen, Vincent

    2011-01-01

    The psychometric structure of the Brief Symptom Inventory-18 (BSI-18; Derogatis, 2001) was investigated using Mokken scaling and parametric item response theory. Data of 487 outpatients, 266 students, and 207 prisoners were analyzed. Results of the Mokken analysis indicated that the BSI-18 formed a

  20. Racial/Ethnic Differences in Responses to the Everyday Discrimination Scale: A Differential Item Functioning Analysis

    OpenAIRE

    Lewis, Tené T.; Yang, Frances M; Jacobs, Elizabeth A.; Fitchett, George

    2012-01-01

    The authors examined the impact of race/ethnicity on responses to the Everyday Discrimination Scale, one of the most widely used discrimination scales in epidemiologic and public health research. Participants were 3,295 middle-aged US women (African-American, Caucasian, Chinese, Hispanic, and Japanese) from the Study of Women’s Health Across the Nation (SWAN) baseline examination (1996–1997). Multiple-indicator, multiple-cause models were used to examine differential item functioning (DIF) on...

  1. Mokken scale analysis: Between the Guttman scale and parametric item response theory

    OpenAIRE

    van Schuur, Wijbrandt H.

    2003-01-01

    This article introduces a model of ordinal unidimensional measurement known as Mokken scale analysis. Mokken scaling is based on principles of Item Response Theory (IRT) that originated in the Guttman scale. I compare the Mokken model with both Classical Test Theory (reliability or factor analysis) and parametric IRT models (especially with the one-parameter logistic model known as the Rasch model). Two nonparametric probabilistic versions of the Mokken model are described: the model of Monot...

  2. Reading ability and print exposure: item response theory analysis of the author recognition test.

    Science.gov (United States)

    Moore, Mariah; Gordon, Peter C

    2015-12-01

    In the author recognition test (ART), participants are presented with a series of names and foils and are asked to indicate which ones they recognize as authors. The test is a strong predictor of reading skill, and this predictive ability is generally explained as occurring because author knowledge is likely acquired through reading or other forms of print exposure. In this large-scale study (1,012 college student participants), we used item response theory (IRT) to analyze item (author) characteristics in order to facilitate identification of the determinants of item difficulty, provide a basis for further test development, and optimize scoring of the ART. Factor analysis suggested a potential two-factor structure of the ART, differentiating between literary and popular authors. Effective and ineffective author names were identified so as to facilitate future revisions of the ART. Analyses showed that the ART is a highly significant predictor of the time spent encoding words, as measured using eyetracking during reading. The relationship between the ART and time spent reading provided a basis for implementing a higher penalty for selecting foils, rather than the standard method of ART scoring (names selected minus foils selected). The findings provide novel support for the view that the ART is a valid indicator of reading volume. Furthermore, they show that frequency data can be used to select items of appropriate difficulty, and that frequency data from corpora based on particular time periods and types of texts may allow adaptations of the test for different populations. PMID:25410405

  3. An IRT Modeling of Change over Time for Repeated Measures Item Response Data Using a Random Weights Linear Logistic Test Model Approach

    Science.gov (United States)

    Paek, Insu; Baek, Sun-Geun; Wilson, Mark

    2012-01-01

    In this study, repeated measures item response data from an English language proficiency (ELP) test administered over 2 years were analyzed by item response theory-based approaches to model change over time. First, change over time was modeled by an item side change approach where change was parameterized at the item level. Second, more…

  4. Item response drift in the Family Affluence Scale: A study on three consecutive surveys of the Health Behaviour in School-aged Children (HBSC) survey

    DEFF Research Database (Denmark)

    Schnohr, Christina Warrer; Makransky, Guido; Kreiner, Svend;

    2013-01-01

    in 2002, 2006 and 2010, and examined the construct validity of the FAS, by focusing on changes in item responses over time. The analyses reported the changes in means in item responses, and fitted models which estimated differential item functioning (DIF), and local dependency (LD) between items. DIF...

  5. Deep brain stimulation and responsiveness of the Persian version of Parkinson's disease questionnaire with 39-items.

    Directory of Open Access Journals (Sweden)

    Gholam Ali Shahidi

    2014-12-01

    Full Text Available Assessment of quality-of-life (QOF as an outcome measure after deep brain stimulation (DBS surgery in patients with Parkinson's disease (PD need a valid, reliable and responsive instrument. The aim of the current study was to determine responsiveness of validated Persian version of PD questionnaire with 39-items (PDQ-39 after DBS surgery in patients with PD.Eleven patients with PD, who were candidate for DBS operation between May 2012 and June 2013 were assessed. PDQ-39 and short-form questionnaire with 36-items (SF-36 were used. To assess responsiveness of PDQ-39 standardized response mean (SRM was used.Mean age was 51.8 (8.8 and all of the patients, but just one were male (10 patients. Mean duration of the disease was 8.7 (2.1 years. Eight patients were categorized as moderate using Hoehn and Yahr (H and Y classification. All patients had a better H and Y score compared with the baseline evaluation (3.09 vs. 0.79. The amount of SRM was above 0.70 for all domains means a large responsiveness for PDQ-39.Persian version of PDQ-39 has an acceptable responsiveness and could be used to assess as an outcome measure to evaluate the effect of therapies on PD.

  6. Guidelines for ensuring socially responsible public procurement : Case city of Espoo, procurement of textile items

    OpenAIRE

    Laukkanen-Kolesnikova, Heini

    2016-01-01

    In modern society, it is essential for companies and municipalities to ensure that all players in the supply chain are acting in a socially responsible way. The purpose of this study was to find out how the city of Espoo can ensure social responsibility in their purchases. The focus of the study was in a procurement of textile items carried out by Espoo during the year 2015. The research for this thesis was based on several qualitative data including the researcher’s observations about...

  7. ltm: An R Package for Latent Variable Modeling and Item Response Analysis

    Directory of Open Access Journals (Sweden)

    Dimitris Rizopoulos

    2006-11-01

    Full Text Available The R package ltm has been developed for the analysis of multivariate dichotomous and polytomous data using latent variable models, under the Item Response Theory approach. For dichotomous data the Rasch, the Two-Parameter Logistic, and Birnbaum's Three-Parameter models have been implemented, whereas for polytomous data Semejima's Graded Response model is available. Parameter estimates are obtained under marginal maximum likelihood using the Gauss-Hermite quadrature rule. The capabilities and features of the package are illustrated using two real data examples.

  8. Validation of Sustainable Development Practices Scale Using the Bayesian Approach to Item Response Theory

    Directory of Open Access Journals (Sweden)

    Martin Hernani Merino

    2014-12-01

    Full Text Available There has been growing recognition of the importance of creating performance measurement tools for the economic, social and environmental management of micro and small enterprise (MSE. In this context, this study aims to validate an instrument to assess perceptions of sustainable development practices by MSEs by means of a Graded Response Model (GRM with a Bayesian approach to Item Response Theory (IRT. The results based on a sample of 506 university students in Peru, suggest that a valid measurement instrument was achieved. At the end of the paper, methodological and managerial contributions are presented.

  9. Online placement test based on Item Response Theory and IMS Global standards

    OpenAIRE

    Merrouch, Farid; Hnida, Meriem; Idrissi, Mohammed Khalidi; Bennani, Samir

    2014-01-01

    This paper aims to present an online placement test. It is based on the Item Response Theory to provide relevant estimates of learner competences. The proposed test is the entry point of our e-Learning system. It gathers the learner response to a set of questions and uses a specific developed algorithm to estimate its level. This algorithm identifies learning gaps, which allows tutors to conceive sequence of courses and remediation adapted to each case of learner, in order to achieve a compet...

  10. A New Item Response Theory Model for Open-Ended Online Homework with Multiple Allowed Attempts

    CERN Document Server

    Gönülateş, Emre

    2015-01-01

    Item Response Theory (IRT) was originally developed in traditional exam settings, and it has been shown that the model does not readily transfer to formative assessment in the form of online homework. We investigate if this is mostly due to learner traits that do not become apparent in exam settings, namely random guessing due to lack of diligence or dedication, and copying work from other students or resources. Both of these traits mask the true ability of the learner, which is the only trait considered in most mainstream unidimensional IRT models. We find that indeed the introduction of these traits allows to better assess the true ability of the learners, as well as to better gauge the quality of assessment items. Correspondence of the model traits to self-reported behavior is investigated and confirmed. We find that of these two traits, copying answers has a larger influence on initial homework attempts than random guessing.

  11. Using a Constructed-Response Instrument to Explore the Effects of Item Position and Item Features on the Assessment of Students' Written Scientific Explanations

    Science.gov (United States)

    Federer, Meghan Rector; Nehm, Ross H.; Opfer, John E.; Pearl, Dennis

    2015-08-01

    A large body of work has been devoted to reducing assessment biases that distort inferences about students' science understanding, particularly in multiple-choice instruments (MCI). Constructed-response instruments (CRI), however, have invited much less scrutiny, perhaps because of their reputation for avoiding many of the documented biases of MCIs. In this study we explored whether known biases of MCIs—specifically item sequencing and surface feature effects—were also apparent in a CRI designed to assess students' understanding of evolutionary change using written explanation (Assessment of COntextual Reasoning about Natural Selection [ACORNS]). We used three versions of the ACORNS CRI to investigate different aspects of assessment structure and their corresponding effect on inferences about student understanding. Our results identified several sources of (and solutions to) assessment bias in this practice-focused CRI. First, along the instrument item sequence, items with similar surface features produced greater sequencing effects than sequences of items with dissimilar surface features. Second, a counterbalanced design (i.e., Latin Square) mitigated this bias at the population level of analysis. Third, ACORNS response scores were highly correlated with student verbosity, despite verbosity being an intrinsically trivial aspect of explanation quality. Our results suggest that as assessments in science education shift toward the measurement of scientific practices (e.g., explanation), it is critical that biases inherent in these types of assessments be investigated empirically.

  12. A Teoria da Resposta ao Item: possíveis contribuições aos estudos em marketing The Item Response Theory: possible contributions to marketing studies

    Directory of Open Access Journals (Sweden)

    Danielle Ramos de Miranda Pereira

    2011-01-01

    Full Text Available A constatação da ampla utilização de escalas multidimensionais por parte dos pesquisadores da área de marketing motivou a elaboração de um artigo com o propósito de discutir a aplicação da Teoria da Resposta ao Item (TRI, bem como apresentar a essa área um método que tem se mostrado bastante eficaz na estimação de construtos comportamentais. Sendo assim, o artigo apresenta uma discussão sobre a TRI, ressaltando seus avanços em relação à Teoria Clássica do Teste (TCT e suas aplicações tradicionais no campo da psicometria e da avaliação educacional. Para verificar sua aplicabilidade nos estudos de marketing, julgou-se adequado conduzir uma aplicação prática da TRI em um estudo envolvendo uma escala já bastante utilizada pelos pesquisadores - a de orientação de mercado (Escala MkTor proposta por Narver e Slater (1990. Os resultados da aplicação demonstraram que, embora o modelo da TRI proposto possa ser considerado satisfatório para a aplicação no contexto da Orientação para o Mercado, existem muitos desafios a serem enfrentados por novos estudos como a construção de uma escala com interpretação prática, indicando o que significa para uma empresa possuir um nível de maturidade associado a um determinado construto. As considerações finais ressaltam que a grande contribuição do artigo aos estudos em marketing é a apresentação de um método alternativo para estimar de forma mais apurada os construtos e avaliar a qualidade dos itens das escalas.The widespread utilization of multidimensional scales by researchers in field of marketing have motivated the conduction of a study to discuss the application of the Item Response Theory (IRT as well as presenting a method that has proved very effective in the estimation of behavioral constructs. Therefore, this article presents a discussion about IRT highlighting its advances regarding the Classical Theory of Tests (CTT and its traditional applications in the

  13. Mild to severe social fears: ranking types of feared social situations using item response theory.

    Science.gov (United States)

    Crome, Erica; Baillie, Andrew

    2014-06-01

    Social anxiety disorder is one of the most common mental disorders, and is associated with long term impairment, distress and vulnerability to secondary disorders. Certain types of social fears are more common than others, with public speaking fears typically the most prevalent in epidemiological surveys. The distinction between performance- and interaction-based fears has been the focus of long-standing debate in the literature, with evidence performance-based fears may reflect more mild presentations of social anxiety. This study aims to explicitly test whether different types of social fears differ in underlying social anxiety severity using item response theory techniques. Different types of social fears were assessed using items from three different structured diagnostic interviews in four different epidemiological surveys in the United States (n=2261, n=5411) and Australia (n=1845, n=1497); and ranked using 2-parameter logistic item response theory models. Overall, patterns of underlying severity indicated by different fears were consistent across the four samples with items functioning across a range of social anxiety. Public performance fears and speaking at meetings/classes indicated the lowest levels of social anxiety, with increasing severity indicated by situations such as being assertive or attending parties. Fears of using public bathrooms or eating, drinking or writing in public reflected the highest levels of social anxiety. Understanding differences in the underlying severity of different types of social fears has important implications for the underlying structure of social anxiety, and may also enhance the delivery of social anxiety treatment at a population level. PMID:24873885

  14. Scaling Users' Perceptions of Library Service Quality Using Item Response Theory: A LibQUAL+ [TM] Study

    Science.gov (United States)

    Wei, Youhua; Thompson, Bruce; Cook, C. Colleen

    2005-01-01

    LibQUAL+[TM] data to date have not been subjected to the modern measurement theory called polytomous item response theory (IRT). The data interpreted here were collected from 42,090 participants who completed the "American English" version of the 22 core LibQUAL+[TM] items, and 12,552 participants from Australia and Europe who completed the…

  15. 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.

  16. Potential application of item-response theory to interpretation of medical codes in electronic patient records

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    Dregan Alex

    2011-12-01

    Full Text Available Abstract Background Electronic patient records are generally coded using extensive sets of codes but the significance of the utilisation of individual codes may be unclear. Item response theory (IRT models are used to characterise the psychometric properties of items included in tests and questionnaires. This study asked whether the properties of medical codes in electronic patient records may be characterised through the application of item response theory models. Methods Data were provided by a cohort of 47,845 participants from 414 family practices in the UK General Practice Research Database (GPRD with a first stroke between 1997 and 2006. Each eligible stroke code, out of a set of 202 OXMIS and Read codes, was coded as either recorded or not recorded for each participant. A two parameter IRT model was fitted using marginal maximum likelihood estimation. Estimated parameters from the model were considered to characterise each code with respect to the latent trait of stroke diagnosis. The location parameter is referred to as a calibration parameter, while the slope parameter is referred to as a discrimination parameter. Results There were 79,874 stroke code occurrences available for analysis. Utilisation of codes varied between family practices with intraclass correlation coefficients of up to 0.25 for the most frequently used codes. IRT analyses were restricted to 110 Read codes. Calibration and discrimination parameters were estimated for 77 (70% codes that were endorsed for 1,942 stroke patients. Parameters were not estimated for the remaining more frequently used codes. Discrimination parameter values ranged from 0.67 to 2.78, while calibration parameters values ranged from 4.47 to 11.58. The two parameter model gave a better fit to the data than either the one- or three-parameter models. However, high chi-square values for about a fifth of the stroke codes were suggestive of poor item fit. Conclusion The application of item response

  17. Racial/Ethnic Differences in Responses to the Everyday Discrimination Scale: A Differential Item Functioning Analysis

    Science.gov (United States)

    Lewis, Tené T.; Yang, Frances M.; Jacobs, Elizabeth A.; Fitchett, George

    2012-01-01

    The authors examined the impact of race/ethnicity on responses to the Everyday Discrimination Scale, one of the most widely used discrimination scales in epidemiologic and public health research. Participants were 3,295 middle-aged US women (African-American, Caucasian, Chinese, Hispanic, and Japanese) from the Study of Women’s Health Across the Nation (SWAN) baseline examination (1996–1997). Multiple-indicator, multiple-cause models were used to examine differential item functioning (DIF) on the Everyday Discrimination Scale by race/ethnicity. After adjustment for age, education, and language of interview, meaningful DIF was observed for 3 (out of 10) items: “receiving poorer service in restaurants or stores,” “being treated as if you are dishonest,” and “being treated with less courtesy than other people” (all P's < 0.001). Consequently, the “profile” of everyday discrimination differed slightly for women of different racial/ethnic groups, with certain “public” experiences appearing to have more salience for African-American and Chinese women and “dishonesty” having more salience for racial/ethnic minority women overall. “Courtesy” appeared to have more salience for Hispanic women only in comparison with African-American women. Findings suggest that the Everyday Discrimination Scale could potentially be used across racial/ethnic groups as originally intended. However, researchers should use caution with items that demonstrated DIF. PMID:22306556

  18. Measuring Consumers’ Environmental Responsibility: A Synthesis of Constructs and Measurement Scale Items

    Directory of Open Access Journals (Sweden)

    K. M. R. Taufique

    2014-04-01

    Full Text Available It is universal that central to all production is consumption. Without proper management, production along with consumption is likely to be the main sources of environmental problems. This very reality calls for consumers to be environmentally responsible in their consumption behavior. The objective of this paper is to prepare a synthesis of all the possible factors and measurement scale items to be used for assessing consumers’ environmental responsibility. For making such synthesis, all major works done on the field have been thoroughly reviewed.The paper comes up with a total of six parameters that include knowledge & awareness, attitude, green consumer value, emotional affinity toward nature, willingness to act and environment related past behavior. These tentative, yet inclusive set of parameters are thought to be useful for guiding the designing of large scale future empirical researches for developing a dependable inclusive set of parameters to test consumer’ environmental responsibility. A conceptual model and possible measurement items are proposed for further empirical research.

  19. Which person variables predict how people benefit from True-False over Constructed Response items?

    Directory of Open Access Journals (Sweden)

    Stella Bollmann

    2015-06-01

    Full Text Available The aim of this study was the investigation of the variable Benefit from TF, which we assumed to be additionally measured when using True-False instead of Constructed Response tests. Subjects who benefit from True-False have an advantage over other subjects in answering Multiple Choice or True-False exams. We expected it to be related to partial knowledge and examined its relation to other personal abilities and traits in a total of n = 106 psychology students. They completed a statistics exam in Constructed Response and True-False format and benefit items were defined as those to which the associated constructed response answer was not correct. Additionally, verbal intelligence and Big 5 measures were obtained. Results confirm the existence of the person variable Benefit from TF and its relation to partial knowledge. Furthermore, benefiters differed from others in conscientiousness and openness to experience variables. However, contrary to expectations, they did not differ in verbal IQ.

  20. Understanding the Relation between Attitude Involvement and Response Latitude Using Item Response Theory

    Science.gov (United States)

    Lake, Christopher J.; Withrow, Scott; Zickar, Michael J.; Wood, Nicole L.; Dalal, Dev K.; Bochinski, Joseph

    2013-01-01

    Adapting the original latitude of acceptance concept to Likert-type surveys, response latitudes are defined as the range of graded response options a person is willing to endorse. Response latitudes were expected to relate to attitude involvement such that high involvement was linked to narrow latitudes (the result of selective, careful…

  1. Mathematical literacy examination items and student errors: An analysis of English Second Language students’ responses

    Directory of Open Access Journals (Sweden)

    Pamela Vale

    2013-04-01

    Full Text Available Mathematical literacy is a real-world practical attribute yet students write a high-stakes examination in order to pass the subject Mathematical Literacy in the National Certificates (Vocational (NC(V. In these examinations, all sources of information are contextualised in language. It can be effortful for English second language students to decode text. The deliberate processing that is required saturates working memory and prevents these students from optimally engaging in problem solving. In this study, 15 items from an NC(V Level 4 Mathematical Literacy examination are selected, as well as 15 student responses to each of these questions. From these responses, those which are incorrect are analysed to determine whether the error is due to insufficient mathematical literacy or a lack of English language proficiency. These results are used as an indication as to whether the examination is fair and valid for this group of students.

  2. Disaster Preparedness and Response: Applied Exposure Science

    Science.gov (United States)

    In 2007, the ISEA, predecessor to ISES, held a special roundtable to discuss lessons learned for exposure science during and following environmental disasters, especially the 9/11 attacks and Hurricane Katrina. Since then, environmental agencies have been involved in responses to...

  3. Deconstructing the architecture of alcohol abuse and dependence symptoms in a community sample of late adolescent and emerging adult women: an item response approach.

    Science.gov (United States)

    Duncan, Alexis E; Agrawal, Arpana; Bucholz, Kathleen K; Sartor, Carolyn E; Madden, Pamela A F; Heath, Andrew C

    2011-07-01

    The objective of this study was to examine the underlying factorial architecture of lifetime DSM-IV alcohol use disorder (AUD) criteria in a population-based sample of adolescent and emerging adult female twins who had ever used alcohol (n=2832; aged 18-25 years), and to determine whether thresholds and factor loadings differed by age. Item response modeling was applied to DSM-IV AUD criteria. Compound criteria (e.g., persistent desire or unsuccessful attempts to quit or cut down) were included as separate items. Of the remaining 16 items, tolerance and use despite physical problems were the most and least commonly endorsed items, respectively. Underlying the items was a single factor representing liability to AUDs. Factor loadings ranged from 0.67 for blackouts to 0.90 for time spent using/recovering from effects. Some items assessing different DSM-IV criteria had very similar measurement characteristics, while others assessing the same criterion showed markedly different thresholds and factor loadings. Compared to that of women aged 21-25 years, the threshold for hazardous use was higher in women aged 18-20 years, but lower for used longer than intended and persistent desire to cut down. After accounting for threshold differences, no variations in discrimination across age groups were observed. In agreement with the extant literature, our findings indicate that the factorial structure of AUD is unidimensional, with no support for the abuse/dependence distinction. Individual components of compound criteria may differ in measurement properties; therefore pooling information from such divergent items will reduce information about the AUD construct. PMID:21306836

  4. Repeatability of food frequency assessment tools in relation to the number of items and response categories included

    OpenAIRE

    Bountziouka, V. (Vassiliki); Bathrellou, E. (Eirini); I. Zazpe; Ezquer, L. (Leyre); Martinez-Gonzalez, M. A.; Panagiotakos, D.B. (Demosthenes B.)

    2012-01-01

    Background: Accuracy of a measurement is a cornerstone in research in order to make robust conclusions about the research hypothesis. Objective: To examine whether the number of items (questions) and the number of responses of consumption included in nutritional assessment tools influence their repeatability. Methods: During 2009, 400 participants (250 from Greece, 37±13 yrs, 34% males and 150 participants from Spain, 39±17 yrs, 41% males) completed a diet index with 11-items a...

  5. The Retrospect and Prospect of Non-parametric Item Response Theory%非参数项目反应理论回顾与展望

    Institute of Scientific and Technical Information of China (English)

    陈婧; 康春花; 钟晓玲

    2013-01-01

      相比参数项目反应理论,非参数项目反应理论提供了更吻合实践情境的理论框架。目前非参数项目反应理论研究主要关注参数估计方法及其比较、数据-模型拟合验证等方面,其应用研究则集中于量表修订及个性数据和项目功能差异分析,而在认知诊断理论基础上发展起来的非参数认知诊断理论更是凸显其应用优势。未来研究应更多侧重于非参数项目反应理论的实践应用,对非参数认知诊断理论的研究也值得关注,以充分发挥非参数方法在实践领域的应用优势。%  Compared to parametric item response theory, non-parametric item response theory provide a more appropriate theoretical framework of practice situations. Non-parametric item response theory research focuses on parameter estimation methods and its comparison, data- model fitting verify etc. currently.Its applied research concentrate on scale amendments, personalized data and differential item functioning analysis. Non-parametric cognitive diagnostic theory which based on the parametric cognitive diagnostic theory gives prominence to the advantages of its application.To give full play to the advantages of non-parametric methods in practice,future studies should emphasis on the application of non-parametric item response theory while cognitive diagnosis of the non-parametric study is also worth of attention.

  6. 非参数项目反应理论回顾与展望%The Retrospect and Prospect of Non-parametric Item Response Theory

    Institute of Scientific and Technical Information of China (English)

    陈婧; 康春花; 钟晓玲

    2013-01-01

      相比参数项目反应理论,非参数项目反应理论提供了更吻合实践情境的理论框架。目前非参数项目反应理论研究主要关注参数估计方法及其比较、数据-模型拟合验证等方面,其应用研究则集中于量表修订及个性数据和项目功能差异分析,而在认知诊断理论基础上发展起来的非参数认知诊断理论更是凸显其应用优势。未来研究应更多侧重于非参数项目反应理论的实践应用,对非参数认知诊断理论的研究也值得关注,以充分发挥非参数方法在实践领域的应用优势。%  Compared to parametric item response theory, non-parametric item response theory provide a more appropriate theoretical framework of practice situations. Non-parametric item response theory research focuses on parameter estimation methods and its comparison, data- model fitting verify etc. currently.Its applied research concentrate on scale amendments, personalized data and differential item functioning analysis. Non-parametric cognitive diagnostic theory which based on the parametric cognitive diagnostic theory gives prominence to the advantages of its application.To give full play to the advantages of non-parametric methods in practice,future studies should emphasis on the application of non-parametric item response theory while cognitive diagnosis of the non-parametric study is also worth of attention.

  7. An examination of the Psychopathy Checklist: Youth Version (PCL:YV) among male adolescent offenders: an item response theory analysis.

    Science.gov (United States)

    Tsang, Siny; Piquero, Alex R; Cauffman, Elizabeth

    2014-12-01

    This study examined the applicability of the Psychopathy Checklist: Youth Version (PCL:YV; Forth, Kosson, & Hare, 2003) among a large sample of serious offending adolescent males. Adopting an item response theory approach, item properties of the PCL:YV were examined using the generalized partial credit model. Results showed that need for stimulation, "irresponsibility," and callous & unemotional were sensitive to changes in respondents' varying psychopathy levels, whereas lack of realistic, long-term goals; superficial charm; and revocation of conditional release were less so (quoted PCL:YV item published with permission by Multi-Health Systems, Inc.; see full permissions statement in footnote 1 in the article; other items are paraphrased). Substantial differential item functioning was also found in 15 of the 20 PCL:YV items among Caucasian, African American, and Hispanic offending boys, indicating that item functioning was not invariant across race/ethnicity. Questions remain regarding whether the construct of psychopathy as assessed with the PCL:YV is equivalent across adolescents in general and across different race/ethnic groups in particular. PMID:25181395

  8. Item Response Theory Analyses of the Parent and Teacher Ratings of the DSM-IV ADHD Rating Scale

    Science.gov (United States)

    Gomez, Rapson

    2008-01-01

    The graded response model (GRM), which is based on item response theory (IRT), was used to evaluate the psychometric properties of the inattention and hyperactivity/impulsivity symptoms in an ADHD rating scale. To accomplish this, parents and teachers completed the DSM-IV ADHD Rating Scale (DARS; Gomez et al., "Journal of Child Psychology and…

  9. A psychometric analysis of the Trait Emotional Intelligence Questionnaire-Short Form (TEIQue-SF) using item response theory.

    Science.gov (United States)

    Cooper, Andrew; Petrides, K V

    2010-09-01

    Trait emotional intelligence refers to a constellation of emotional self-perceptions located at the lower levels of personality hierarchies. In 2 studies, we sought to examine the psychometric properties of the Trait Emotional Intelligence Questionnaire-Short Form (TEIQue-SF; Petrides, 2009) using item response theory (IRT). Study 1 (N= 1,119, 455 men) showed that most items had good discrimination and threshold parameters and high item information values. At the global level, the TEIQue-SF showed very good precision across most of the latent trait range. Study 2 (N= 866, 432 men) used similar IRT techniques in a new sample based on the latest version of the TEIQue-SF (version 1.50). Results replicated Study 1, with the instrument showing good psychometric properties at the item and global level. Overall, the 2 studies suggest the TEIQue-SF can be recommended when a rapid assessment of trait emotional intelligence is required. PMID:20706931

  10. Contribution of reactive and proactive control to children's working memory performance: Insight from item recall durations in response sequence planning.

    Science.gov (United States)

    Chevalier, Nicolas; James, Tiffany D; Wiebe, Sandra A; Nelson, Jennifer Mize; Espy, Kimberly Andrews

    2014-07-01

    The present study addressed whether developmental improvement in working memory span task performance relies upon a growing ability to proactively plan response sequences during childhood. Two hundred thirteen children completed a working memory span task in which they used a touchscreen to reproduce orally presented sequences of animal names. Children were assessed longitudinally at 7 time points between 3 and 10 years of age. Twenty-one young adults also completed the same task. Proactive response sequence planning was assessed by comparing recall durations for the 1st item (preparatory interval) and subsequent items. At preschool age, the preparatory interval was generally shorter than subsequent item recall durations, whereas it was systematically longer during elementary school and in adults. Although children mostly approached the task reactively at preschool, they proactively planned response sequences with increasing efficiency from age 7 on, like adults. These findings clarify the nature of the changes in executive control that support working memory performance with age. PMID:24773104

  11. Proposta de um instrumento de medida para avaliar a satisfação de clientes de bancos utilizando a Teoria da Resposta ao Item Proposal of tool to assess the satisfaction of bank customers using the Item Response Theory

    Directory of Open Access Journals (Sweden)

    Alceu Balbim Junior

    2011-01-01

    Full Text Available Este artigo apresenta um instrumento de medida para avaliação da satisfação de clientes de bancos utilizando a Teoria da Resposta ao Item (TRI. Satisfazer os clientes tem sido uma busca constante das organizações que procuram manterem-se competitivas no mercado. Estudos constatam a relação entre a qualidade percebida pelos clientes, a satisfação e fidelidade. A avaliação da satisfação pode ser realizada por meio da qualidade percebida pelos clientes e a construção de ferramentas de avaliação deve contemplar características específicas da atividade em questão. Embasando-se em artigos que avaliam a satisfação de clientes de bancos, propõe-se um instrumento formado por 29 itens. Os itens foram aplicados a 240 clientes a fim de avaliar a satisfação com o banco de maior relacionamento. Utilizando a Teoria da Resposta ao Item, foram identificados os parâmetros dos itens e a curva de informação. A análise do grau de discriminação dos itens indicou que todos são apropriados. A curva de informação obtida evidenciou o intervalo no qual o instrumento apresenta melhores estimativas para níveis de satisfação. O trabalho apresentou o nível médio de satisfação da amostra e a concentração de clientes nos diferentes níveis de satisfação da escala.This paper presents a model for assessing the satisfaction of bank customers using the Item Response Theory (IRT. Organizations are constantly making effort to satisfy customers seeking to remain competitive. Several studies have reported on the relationship between perceived quality, satisfaction, and loyalty. The assessment of satisfaction can be accomplished through the perceived quality, and the development of assessment tools should address specific features of the activity in question. Based on articles that assess the satisfaction of bank customers, this study proposes an assessment tool consisting of 29 items. The items were applied to 240 clients to assess their

  12. Bifactor and Item Response Theory Analyses of Interviewer Report Scales of Cognitive Impairment in Schizophrenia

    Science.gov (United States)

    Reise, Steven P.; Ventura, Joseph; Keefe, Richard S. E.; Baade, Lyle E.; Gold, James M.; Green, Michael F.; Kern, Robert S.; Mesholam-Gately, Raquelle; Nuechterlein, Keith H.; Seidman, Larry J.; Bilder, Robert

    2011-01-01

    A psychometric analysis of 2 interview-based measures of cognitive deficits was conducted: the 21-item Clinical Global Impression of Cognition in Schizophrenia (CGI-CogS; Ventura et al., 2008), and the 20-item Schizophrenia Cognition Rating Scale (SCoRS; Keefe et al., 2006), which were administered on 2 occasions to a sample of people with…

  13. 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…

  14. Interpreting gains and losses in conceptual test using Item Response Theory

    CERN Document Server

    Lamine, Brahim

    2015-01-01

    Conceptual tests are widely used by physics instructors to assess students' conceptual understanding and compare teaching methods. It is common to look at students' changes in their answers between a pre-test and a post-test to quantify a transition in student's conceptions. This is often done by looking at the proportion of incorrect answers in the pre-test that changes to correct answers in the post-test -- the gain -- and the proportion of correct answers that changes to incorrect answers -- the loss. By comparing theoretical predictions to experimental data on the Force Concept Inventory, we shown that Item Response Theory (IRT) is able to fairly well predict the observed gains and losses. We then use IRT to quantify the student's changes in a test-retest situation when no learning occurs and show that $i)$ up to 25\\% of total answers can change due to the non-deterministic nature of student's answer and that $ii)$ gains and losses can go from 0\\% to 100\\%. Still using IRT, we highlight the conditions tha...

  15. How Can Multivariate Item Response Theory Be Used in Reporting of Susbcores? Research Report. ETS RR-10-09

    Science.gov (United States)

    Haberman, Shelby J.; Sinharay, Sandip

    2010-01-01

    Recently, there has been increasing interest in reporting diagnostic scores. This paper examines reporting of subscores using multidimensional item response theory (MIRT) models. An MIRT model is fitted using a stabilized Newton-Raphson algorithm (Haberman, 1974, 1988) with adaptive Gauss-Hermite quadrature (Haberman, von Davier, & Lee, 2008). A…

  16. Taking the Missing Propensity into Account When Estimating Competence Scores: Evaluation of Item Response Theory Models for Nonignorable Omissions

    Science.gov (United States)

    Köhler, Carmen; Pohl, Steffi; Carstensen, Claus H.

    2015-01-01

    When competence tests are administered, subjects frequently omit items. These missing responses pose a threat to correctly estimating the proficiency level. Newer model-based approaches aim to take nonignorable missing data processes into account by incorporating a latent missing propensity into the measurement model. Two assumptions are typically…

  17. Increasing the Number of Replications in Item Response Theory Simulations: Automation through SAS and Disk Operating System

    Science.gov (United States)

    Gagne, Phill; Furlow, Carolyn; Ross, Terris

    2009-01-01

    In item response theory (IRT) simulation research, it is often necessary to use one software package for data generation and a second software package to conduct the IRT analysis. Because this can substantially slow down the simulation process, it is sometimes offered as a justification for using very few replications. This article provides…

  18. 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…

  19. Development of a Short Version of MSQOL-54 Using Factor Analysis and Item Response Theory

    Science.gov (United States)

    Rosato, Rosalba; Testa, Silvia; Bertolotto, Antonio; Confalonieri, Paolo; Patti, Francesco; Lugaresi, Alessandra; Grasso, Maria Grazia; Toscano, Anna; Giordano, Andrea; Solari, Alessandra

    2016-01-01

    Background The Multiple Sclerosis Quality of Life-54 (MSQOL-54, 52 items grouped in 12 subscales plus two single items) is the most used MS specific health related quality of life inventory. Objective To develop a shortened version of the MSQOL-54. Methods MSQOL-54 dimensionality and metric properties were investigated by confirmatory factor analysis (CFA) and Rasch modelling (Partial Credit Model, PCM) on MSQOL-54s completed by 473 MS patients. Their mean age was 41 years, 65% were women, and median Expanded Disability Status Scale (EDSS) score was 2.0 (range 0–9.5). Differential item functioning (DIF) was evaluated for gender, age and EDSS. Dimensionality of the resulting short version was assessed by exploratory factor analysis (EFA) and CFA. Cognitive debriefing of the short instrument (vs. the original) was then performed on 12 MS patients. Results CFA of MSQOL-54 subscales showed that the data fitted the overall model well. Two subscales (Role Limitations—Physical, Role Limitations—Emotional) did not fit the PCM, and were removed; two other subscales (Health Perceptions, Social Function) did not fit the model, but were retained as single items. Sexual Satisfaction (single-item subscale) was also removed. The resulting MSQOL-29 consisted of 25 items grouped in 7 subscales, plus 4 single items. PCM fit statistics were within the acceptability range for all MSQOL-29 items except one which had significant DIF by age. EFA and CFA indicated adequate fit to the original two-factor (Physical and Mental Health Composites) hypothesis. Cognitive debriefing confirmed that MSQOL-29 was acceptable and had lost no key items. Conclusions The proposed MSQOL-29 is 50% shorter than MSQOL-54, yet preserves key quality of life dimensions. Prospective validation on a large, independent MS patient sample is ongoing. PMID:27078146

  20. Small Sample Estimation in Dichotomous Item Response Models: Effect of Priors Based on Judgmental Information on the Accuracy of Item Parameter Estimates. LSAC Research Report Series.

    Science.gov (United States)

    Swaminathan, Hariharan; Hambleton, Ronald K.; Sireci, Stephen G.; Xing, Dehui; Rizavi, Saba M.

    The primary objective of this study was to investigate how incorporating prior information improves estimation of item parameters in two small samples. The factors that were investigated were sample size and the type of prior information. To investigate the accuracy with which item parameters in the Law School Admission Test (LSAT) are estimated,…

  1. Item Characteristic Curve Estimation of Signal Detection Theory-Based Personality Data: A Two-Stage Approach to Item Response Modeling.

    Science.gov (United States)

    Williams, Kevin M.; Zumbo, Bruno D.

    2003-01-01

    Developed an item characteristic curve estimation of signal detection theory based personality data. Results for 266 college students taking the Overclaiming Questionnaire (D. Paulhus and N. Bruce, 1990) suggest that this method is a reasonable approach to describing item functioning and that there are advantages to this method over traditional…

  2. Applying Systems Design and Item Response Theory to the Problem of Measuring Information Literacy Skills.

    Science.gov (United States)

    O'Connor, Lisa G.; Radcliff, Carolyn J.; Gedeon, Julie A.

    2002-01-01

    Reports on the development of the Standardized Assessment of Information Literacy Skills (SAILS) at Kent State University (Ohio) for programmatic-level assessment of information literacy skills. Once validated, the instrument will be used to assess entry skills upon admission and longitudinally to ascertain whether there is significant change in…

  3. Test Equating of the Medical Licensing Examination in 2003 and 2004 Based on the Item Response Theory

    Directory of Open Access Journals (Sweden)

    Mi Kyoung Yim

    2006-07-01

    Full Text Available The passing rate of the Medical Licensing Examination has been variable, which probably originated from the difference in the difficulty of items and/or difference in the ability level of examinees. We tried to explain the origin of the difference using the test equating method based on the item response theory. The number of items and examinees were 500, 3,647 in 2003 and 550, 3,879 in 2004. Common item nonequivalent group design was used for 30 common items. Item and ability parameters were calculated by three parametric logistic models using ICL. Scale transformation and true score equating were executed using ST and PIE. The mean of difficulty index of the year 2003 was ??.957 (SD 2.628 and that of 2004 after equating was ??.456 (SD 3.399. The mean of discrimination index of year 2003 was 0.487 (SD 0.242 and that of 2004 was 0.363 (SD 0.193. The mean of ability parameter of year 2003 was 0.00617 (SD 0.96605 and that of year 2004 was 0.94636 (SD 1.32960. The difference of the equated true score at the same ability level was high at the range of score of 200??50. The reason for the difference in passing rates over two consecutive years was due to the fact that the Examination in 2004 was easier and the abilities of the examinees in 2004 were higher. In addition, the passing rates of examinees with score of 270??94 in 2003, and those with 322??43 in 2004, were affected by the examination year.

  4. Comparisons across depression assessment instruments in adolescence and young adulthood: An Item Response Theory study using two linking methods

    OpenAIRE

    Olino, Thomas M.; Yu, Lan; McMakin, Dana L.; Forbes, Erika E.; John R. Seeley; Lewinsohn, Peter M.; Pilkonis, Paul A.

    2013-01-01

    Item response theory (IRT) methods allow for comparing the utility of instruments based on the range and precision of severity assessed by each instrument. As adolescents and young adults can display rapid increases in depressive symptoms, there is a crucial need to sensitively assess mild elevations of symptoms (as an index of initial risk) and moderate-severe symptoms (as an indicator of treatment disposition). We compare the information assessed by the Beck Depression Inventory (BDI) to th...

  5. Implicit Theories and Beta Change in Longitudinal Evaluations of Training Effectiveness: An Investigation Using Item Response Theory

    OpenAIRE

    Craig, Stephen Bartholomew

    2002-01-01

    Golembiewski, Billingsly, and Yeager (1976) conceptualized three distinct types of change that might result from development interventions, called alpha, beta, and gamma change. Recent research has found that beta and gamma change do occur as hypothesized, but the phenomena are somewhat infrequent and the precise conditions under which they occur have not been established. This study used confirmatory factor analysis and item response theory to identify gamma and beta change on a multidimensi...

  6. Item analysis of single-peaked response data : the psychometric evaluation of bipolar measurement scales

    NARCIS (Netherlands)

    Polak, Maaike Geertruida

    2011-01-01

    The thesis explains the fundamental difference between unipolar and bipolar measurement scales for psychological characteristics. We explore the use of correspondence analysis (CA), a technique that is similar to principal component analysis and is available in SAS and SPSS, to select items that tog

  7. A Substantive Process Analysis of Responses to Items from the Multistate Bar Examination

    Science.gov (United States)

    Bonner, Sarah M.; D'Agostino, Jerome V.

    2012-01-01

    We investigated examinees' cognitive processes while they solved selected items from the Multistate Bar Exam (MBE), a high-stakes professional certification examination. We focused on ascertaining those mental processes most frequently used by examinees, and the most common types of errors in their thinking. We compared the relationships between…

  8. Partially Compensatory Multidimensional Item Response Theory Models: Two Alternate Model Forms

    Science.gov (United States)

    DeMars, Christine E.

    2016-01-01

    Partially compensatory models may capture the cognitive skills needed to answer test items more realistically than compensatory models, but estimating the model parameters may be a challenge. Data were simulated to follow two different partially compensatory models, a model with an interaction term and a product model. The model parameters were…

  9. A responsible agenda for applied linguistics: Confessions of a philosopher

    Directory of Open Access Journals (Sweden)

    Albert Weideman

    2011-08-01

    Full Text Available When we undertake academic, disciplinary work, we rely on philosophical starting points. Several straightforward illustrations of this can be found in the history of applied linguistics. It is evident from the history of our field that various historically influential approaches to our discipline base themselves upon different academic confessions. This paper examines the effects of basing our applied linguistic work on the idea that applied linguistics is a discipline concerned with design. Such a characterisation does justice to both modernist and postmodernist emphases in applied linguistics. Conceptualisations of applied linguistics that came with the proposals for communicative language teaching (CLT some thirty to forty years ago propelled the discipline squarely into postmodern times. To account for this, we need to develop a theory of applied linguistics which shows what constitutive and regulative conditions exist for doing applied linguistic designs. A responsible agenda for applied linguistics today has as its first responsibility to free the users of its designs from toil and drudgery, as well as from becoming victims of fashion, ideology or theory. Secondly, it should design solutions to language problems in such a way that the technical imagination of the designer is not restricted but supported by theory and empirical investigation, and that the productive pedagogical fantasy of the implementers of such plans is set free. Thirdly, it must seek to become accountable by designing theoretically and socially defensible solutions to language problems, solutions that relieve some of the suffering, pain, poverty and injustice in our world.

  10. Recovery of Item Parameters in the Nominal Response Model: A Comparison of Marginal Maximum Likelihood Estimation and Markov Chain Monte Carlo Estimation.

    Science.gov (United States)

    Wollack, James A.; Bolt, Daniel M.; Cohen, Allan S.; Lee, Young-Sun

    2002-01-01

    Compared the quality of item parameter estimates for marginal maximum likelihood (MML) and Markov Chain Monte Carlo (MCMC) with the nominal response model using simulation. The quality of item parameter recovery was nearly identical for MML and MCMC, and both methods tended to produce good estimates. (SLD)

  11. Testing whether the DSM-5 personality disorder trait model can be measured with a reduced set of items: An item response theory investigation of the Personality Inventory for DSM-5.

    Science.gov (United States)

    Maples, Jessica L; Carter, Nathan T; Few, Lauren R; Crego, Cristina; Gore, Whitney L; Samuel, Douglas B; Williamson, Rachel L; Lynam, Donald R; Widiger, Thomas A; Markon, Kristian E; Krueger, Robert F; Miller, Joshua D

    2015-12-01

    The fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) includes an alternative model of personality disorders (PDs) in Section III, consisting in part of a pathological personality trait model. To date, the 220-item Personality Inventory for DSM-5 (PID-5; Krueger, Derringer, Markon, Watson, & Skodol, 2012) is the only extant self-report instrument explicitly developed to measure this pathological trait model. The present study used item response theory-based analyses in a large sample (n = 1,417) to investigate whether a reduced set of 100 items could be identified from the PID-5 that could measure the 25 traits and 5 domains. This reduced set of PID-5 items was then tested in a community sample of adults currently receiving psychological treatment (n = 109). Across a wide range of criterion variables including NEO PI-R domains and facets, DSM-5 Section II PD scores, and externalizing and internalizing outcomes, the correlational profiles of the original and reduced versions of the PID-5 were nearly identical (rICC = .995). These results provide strong support for the hypothesis that an abbreviated set of PID-5 items can be used to reliably, validly, and efficiently assess these personality disorder traits. The ability to assess the DSM-5 Section III traits using only 100 items has important implications in that it suggests these traits could still be measured in settings in which assessment-related resources (e.g., time, compensation) are limited. PMID:25844534

  12. Using item response theory to study the convergent and discriminant validity of three questionnaires measuring cigarette dependence.

    Science.gov (United States)

    Courvoisier, Delphine; Etter, Jean-François

    2008-09-01

    To determine whether the Cigarette Dependence Scale, the Fagerström Test for Nicotine Dependence, and the Nicotine Dependence Syndrome Scale (NDSS) reliably and correctly assessed both weakly and severely dependent individuals, the authors collected data via Internet from 2,435 current smokers, from 2004 to 2007. They used a 2-parameter item response model to determine the difficulty and discrimination of each question and used correlations between latent scores to assess convergent and discriminant validity. The reliability of all scales was close to or exceeded .70. Both the Cigarette Dependence Scale and the Fagerström Test for Nicotine Dependence had 1 misfitting item. Each NDSS scale had at least 2 misfitting items. The information curve of each of the questionnaires peaked between -2 and 2 and was low at both extremes. All questionnaires had adequate reliability and were more informative for a medium level of the underlying cigarette dependence continuum than for both extremes of this continuum. The correlations between latent scores indicated good convergent validity between questionnaires and low discriminant validity between NDSS subscales, except for Tolerance. This result suggests that nicotine dependence may not be composed of 5 dimensions but may be unidimensional and distinct from reduced sensitivity to the effects of smoking (Tolerance). PMID:18778132

  13. 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…

  14. What range of trait levels can the Autism-Spectrum Quotient (AQ) measure reliably? An item response theory analysis.

    Science.gov (United States)

    Murray, Aja Louise; Booth, Tom; McKenzie, Karen; Kuenssberg, Renate

    2016-06-01

    It has previously been noted that inventories measuring traits that originated in a psychopathological paradigm can often reliably measure only a very narrow range of trait levels that are near and above clinical cutoffs. Much recent work has, however, suggested that autism spectrum disorder traits are on a continuum of severity that extends well into the nonclinical range. This implies a need for inventories that can capture individual differences in autistic traits from very high levels all the way to the opposite end of the continuum. The Autism-Spectrum Quotient (AQ) was developed based on a closely related rationale, but there has, to date, been no direct test of the range of trait levels that the AQ can reliably measure. To assess this, we fit a bifactor item response theory model to the AQ. Results suggested that AQ measures moderately low to moderately high levels of a general autistic trait with good measurement precision. The reliable range of measurement was significantly improved by scoring the instrument using its 4-point response scale, rather than dichotomizing responses. These results support the use of the AQ in nonclinical samples, but suggest that items measuring very low and very high levels of autistic traits would be beneficial additions to the inventory. (PsycINFO Database Record PMID:26302097

  15. Factors affecting study efficiency and item non-response in health surveys in developing countries: the Jamaica national healthy lifestyle survey

    Directory of Open Access Journals (Sweden)

    Bennett Franklyn

    2007-02-01

    Full Text Available Abstract Background Health surveys provide important information on the burden and secular trends of risk factors and disease. Several factors including survey and item non-response can affect data quality. There are few reports on efficiency, validity and the impact of item non-response, from developing countries. This report examines factors associated with item non-response and study efficiency in a national health survey in a developing Caribbean island. Methods A national sample of participants aged 15–74 years was selected in a multi-stage sampling design accounting for 4 health regions and 14 parishes using enumeration districts as primary sampling units. Means and proportions of the variables of interest were compared between various categories. Non-response was defined as failure to provide an analyzable response. Linear and logistic regression models accounting for sample design and post-stratification weighting were used to identify independent correlates of recruitment efficiency and item non-response. Results We recruited 2012 15–74 year-olds (66.2% females at a response rate of 87.6% with significant variation between regions (80.9% to 97.6%; p Conclusion Informative health surveys are possible in developing countries. While survey response rates may be satisfactory, item non-response was high in respect of income and sexual practice. In contrast to developed countries, non-response to questions on income is higher and has different correlates. These findings can inform future surveys.

  16. The Effect of Response Format on the Psychometric Properties of the Narcissistic Personality Inventory: Consequences for Item Meaning and Factor Structure.

    Science.gov (United States)

    Ackerman, Robert A; Donnellan, M Brent; Roberts, Brent W; Fraley, R Chris

    2016-04-01

    The Narcissistic Personality Inventory (NPI) is currently the most widely used measure of narcissism in social/personality psychology. It is also relatively unique because it uses a forced-choice response format. We investigate the consequences of changing the NPI's response format for item meaning and factor structure. Participants were randomly assigned to one of three conditions: 40 forced-choice items (n = 2,754), 80 single-stimulus dichotomous items (i.e., separate true/false responses for each item; n = 2,275), or 80 single-stimulus rating scale items (i.e., 5-point Likert-type response scales for each item; n = 2,156). Analyses suggested that the "narcissistic" and "nonnarcissistic" response options from the Entitlement and Superiority subscales refer to independent personality dimensions rather than high and low levels of the same attribute. In addition, factor analyses revealed that although the Leadership dimension was evident across formats, dimensions with entitlement and superiority were not as robust. Implications for continued use of the NPI are discussed. PMID:25616401

  17. Uncertainties in the Item Parameter Estimates and Robust Automated Test Assembly

    Science.gov (United States)

    Veldkamp, Bernard P.; Matteucci, Mariagiulia; de Jong, Martijn G.

    2013-01-01

    Item response theory parameters have to be estimated, and because of the estimation process, they do have uncertainty in them. In most large-scale testing programs, the parameters are stored in item banks, and automated test assembly algorithms are applied to assemble operational test forms. These algorithms treat item parameters as fixed values,…

  18. Item response theory analysis of the Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised in the Pooled Resource Open-Access ALS Clinical Trials Database.

    Science.gov (United States)

    Bacci, Elizabeth D; Staniewska, Dorota; Coyne, Karin S; Boyer, Stacey; White, Leigh Ann; Zach, Neta; Cedarbaum, Jesse M

    2016-01-01

    Our objective was to examine dimensionality and item-level performance of the Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised (ALSFRS-R) across time using classical and modern test theory approaches. Confirmatory factor analysis (CFA) and Item Response Theory (IRT) analyses were conducted using data from patients with amyotrophic lateral sclerosis (ALS) Pooled Resources Open-Access ALS Clinical Trials (PRO-ACT) database with complete ALSFRS-R data (n = 888) at three time-points (Time 0, Time 1 (6-months), Time 2 (1-year)). Results demonstrated that in this population of 888 patients, mean age was 54.6 years, 64.4% were male, and 93.7% were Caucasian. The CFA supported a 4* individual-domain structure (bulbar, gross motor, fine motor, and respiratory domains). IRT analysis within each domain revealed misfitting items and overlapping item response category thresholds at all time-points, particularly in the gross motor and respiratory domain items. Results indicate that many of the items of the ALSFRS-R may sub-optimally distinguish among varying levels of disability assessed by each domain, particularly in patients with less severe disability. Measure performance improved across time as patient disability severity increased. In conclusion, modifications to select ALSFRS-R items may improve the instrument's specificity to disability level and sensitivity to treatment effects. PMID:26473473

  19. An autoregressive growth model for longitudinal item analysis.

    Science.gov (United States)

    Jeon, Minjeong; Rabe-Hesketh, Sophia

    2016-09-01

    A first-order autoregressive growth model is proposed for longitudinal binary item analysis where responses to the same items are conditionally dependent across time given the latent traits. Specifically, the item response probability for a given item at a given time depends on the latent trait as well as the response to the same item at the previous time, or the lagged response. An initial conditions problem arises because there is no lagged response at the initial time period. We handle this problem by adapting solutions proposed for dynamic models in panel data econometrics. Asymptotic and finite sample power for the autoregressive parameters are investigated. The consequences of ignoring local dependence and the initial conditions problem are also examined for data simulated from a first-order autoregressive growth model. The proposed methods are applied to longitudinal data on Korean students' self-esteem. PMID:26645083

  20. Culturally Sensitive Depression Assessment for Chinese American Immigrants: Development of a Comprehensive Measure and a Screening Scale Using an Item Response Approach

    OpenAIRE

    Wong, Rose; Wu, Rufina; Guo, Carmen; Lam, Julia K.; Snowden, Lonnie R.

    2011-01-01

    The present mixed methods study developed a comprehensive measure and a screening scale of depression for Chinese American immigrants by combining an emic approach with item response analysis. Clinical participants were immigrants diagnosed by licensed clinicians who worked in the community. Qualitative interviews with clinicians and clinical participants (N = 63) supported the definition of the construct of depression—which guided scale development—and a 47-item pilot scale. Clinical and com...

  1. 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.

  2. An overview of the Normal Ogive Harmonic Analysis Robust Method (NOHARM) approach to item response theory

    OpenAIRE

    Lee, J J; Lee, M. K.

    2016-01-01

    Here we provide a description of the IRT estimation method known as Normal Ogive Harmonic Analysis Robust Method (NOHARM). Although in some ways this method has been superseded by new computer programs that also adopt a specifically factor-analytic approach, its fundamental principles remain useful in certain applications, which include calculating the residual covariance matrix and rescaling the distribution of the common factor (latent trait). These principles can be applied to parameter es...

  3. The Elements of Item Response Theory and its Framework in Analyzing Introductory Astronomy College Student Misconceptions. I. Galaxies

    CERN Document Server

    Favia, Andrej; Thorpe, Geoffrey L

    2013-01-01

    This is the first in a series of papers that analyze college student beliefs in realms where common astronomy misconceptions are prevalent. Data was collected through administration of an inventory distributed at the end of an introductory college astronomy course. In this paper, we present the basic mathematics of item response theory (IRT), and then we use it to explore concepts related to galaxies. We show how IRT determines the difficulty of each galaxy topic under consideration. We find that the concept of galaxy spatial distribution presents the greatest challenge to students of all the galaxy topics. We also find and present the most logical sequence to teach galaxy topics as a function of the audience's age.

  4. Lessons from the Ebola Outbreak: Action Items for Emerging Infectious Disease Preparedness and Response.

    Science.gov (United States)

    Jacobsen, Kathryn H; Aguirre, A Alonso; Bailey, Charles L; Baranova, Ancha V; Crooks, Andrew T; Croitoru, Arie; Delamater, Paul L; Gupta, Jhumka; Kehn-Hall, Kylene; Narayanan, Aarthi; Pierobon, Mariaelena; Rowan, Katherine E; Schwebach, J Reid; Seshaiyer, Padmanabhan; Sklarew, Dann M; Stefanidis, Anthony; Agouris, Peggy

    2016-03-01

    As the Ebola outbreak in West Africa wanes, it is time for the international scientific community to reflect on how to improve the detection of and coordinated response to future epidemics. Our interdisciplinary team identified key lessons learned from the Ebola outbreak that can be clustered into three areas: environmental conditions related to early warning systems, host characteristics related to public health, and agent issues that can be addressed through the laboratory sciences. In particular, we need to increase zoonotic surveillance activities, implement more effective ecological health interventions, expand prediction modeling, support medical and public health systems in order to improve local and international responses to epidemics, improve risk communication, better understand the role of social media in outbreak awareness and response, produce better diagnostic tools, create better therapeutic medications, and design better vaccines. This list highlights research priorities and policy actions the global community can take now to be better prepared for future emerging infectious disease outbreaks that threaten global public health and security. PMID:26915507

  5. Which person variables predict how people benefit from True-False over Constructed Response items?

    OpenAIRE

    Stella Bollmann; Eva Böbel; Moritz Heene

    2015-01-01

    The aim of this study was the investigation of the variable Benefit from TF, which we assumed to be additionally measured when using True-False instead of Constructed Response tests. Subjects who benefit from True-False have an advantage over other subjects in answering Multiple Choice or True-False exams. We expected it to be related to partial knowledge and examined its relation to other personal abilities and traits in a total of n = 106 psychology students. They completed a statistics exa...

  6. Developmental changes in reading do not alter the development of visual processing skills: an application of explanatory item response models in grades K-2.

    Science.gov (United States)

    Santi, Kristi L; Kulesz, Paulina A; Khalaf, Shiva; Francis, David J

    2015-01-01

    Visual processing has been widely studied in regard to its impact on a students' ability to read. A less researched area is the role of reading in the development of visual processing skills. A cohort-sequential, accelerated-longitudinal design was utilized with 932 kindergarten, first, and second grade students to examine the impact of reading acquisition on the processing of various types of visual discrimination and visual motor test items. Students were assessed four times per year on a variety of reading measures and reading precursors and two popular measures of visual processing over a 3-year period. Explanatory item response models were used to examine the roles of person and item characteristics on changes in visual processing abilities and changes in item difficulties over time. Results showed different developmental patterns for five types of visual processing test items, but most importantly failed to show consistent effects of learning to read on changes in item difficulty. Thus, the present study failed to find support for the hypothesis that learning to read alters performance on measures of visual processing. Rather, visual processing and reading ability improved together over time with no evidence to suggest cross-domain influences from reading to visual processing. Results are discussed in the context of developmental theories of visual processing and brain-based research on the role of visual skills in learning to read. PMID:25717311

  7. Developmental changes in reading do not alter the development of visual processing skills: An application of explanatory item response models in grades K-2

    Directory of Open Access Journals (Sweden)

    Kristi L Santi

    2015-02-01

    Full Text Available Visual processing has been widely studied in regard to its impact on a students’ ability to read. A less researched area is the role of reading in the development of visual processing skills. A cohort-sequential, accelerated-longitudinal design was utilized with 932 kindergarten, first, and second grade students to examine the impact of reading acquisition on the processing of various types of visual discrimination and visual motor test items. Students were assessed four times per year on a variety of reading measures and reading precursors and two popular measures of visual processing over a three-year period. Explanatory item response models were used to examine the roles of person and item characteristics on changes in visual processing abilities and changes in item difficulties over time. Results showed different developmental patterns for five types of visual processing test items, but most importantly failed to show consistent effects of learning to read on changes in item difficulty. Thus, the present study failed to find support for the hypothesis that learning to read alters performance on measures of visual processing. Rather, visual processing and reading ability improved together over time with no evidence to suggest cross-domain influences from reading to visual processing. Results are discussed in the context of developmental theories of visual processing and brain-based research on the role of visual skills in learning to read.

  8. Calibrating the Medical Council of Canada’s Qualifying Examination Part I using an integrated item response theory framework: a comparison of models and designs

    Science.gov (United States)

    2016-01-01

    Purpose: The aim of this research was to compare different methods of calibrating multiple choice question (MCQ) and clinical decision making (CDM) components for the Medical Council of Canada’s Qualifying Examination Part I (MCCQEI) based on item response theory. Methods: Our data consisted of test results from 8,213 first time applicants to MCCQEI in spring and fall 2010 and 2011 test administrations. The data set contained several thousand multiple choice items and several hundred CDM cases. Four dichotomous calibrations were run using BILOG-MG 3.0. All 3 mixed item format (dichotomous MCQ responses and polytomous CDM case scores) calibrations were conducted using PARSCALE 4. Results: The 2-PL model had identical numbers of items with chi-square values at or below a Type I error rate of 0.01 (83/3,499 or 0.02). In all 3 polytomous models, whether the MCQs were either anchored or concurrently run with the CDM cases, results suggest very poor fit. All IRT abilities estimated from dichotomous calibration designs correlated very highly with each other. IRT-based pass-fail rates were extremely similar, not only across calibration designs and methods, but also with regard to the actual reported decision to candidates. The largest difference noted in pass rates was 4.78%, which occurred between the mixed format concurrent 2-PL graded response model (pass rate= 80.43%) and the dichotomous anchored 1-PL calibrations (pass rate= 85.21%). Conclusion: Simpler calibration designs with dichotomized items should be implemented. The dichotomous calibrations provided better fit of the item response matrix than more complex, polytomous calibrations. PMID:26883811

  9. Calibrating the Medical Council of Canada’s Qualifying Examination Part I using an integrated item response theory framework: a comparison of models and designs

    Directory of Open Access Journals (Sweden)

    Andre F. De Champlain

    2016-01-01

    Full Text Available Purpose: The aim of this research was to compare different methods of calibrating multiple choice question (MCQ and clinical decision making (CDM components for the Medical Council of Canada’s Qualifying Examination Part I (MCCQEI based on item response theory. Methods: Our data consisted of test results from 8,213 first time applicants to MCCQEI in spring and fall 2010 and 2011 test administrations. The data set contained several thousand multiple choice items and several hundred CDM cases. Four dichotomous calibrations were run using BILOG-MG 3.0. All 3 mixed item format (dichotomous MCQ responses and polytomous CDM case scores calibrations were conducted using PARSCALE 4. Results: The 2-PL model had identical numbers of items with chi-square values at or below a Type I error rate of 0.01 (83/3,499 or 0.02. In all 3 polytomous models, whether the MCQs were either anchored or concurrently run with the CDM cases, results suggest very poor fit. All IRT abilities estimated from dichotomous calibration designs correlated very highly with each other. IRT-based pass-fail rates were extremely similar, not only across calibration designs and methods, but also with regard to the actual reported decision to candidates. The largest difference noted in pass rates was 4.78%, which occurred between the mixed format concurrent 2-PL graded response model (pass rate= 80.43% and the dichotomous anchored 1-PL calibrations (pass rate= 85.21%. Conclusion: Simpler calibration designs with dichotomized items should be implemented. The dichotomous calibrations provided better fit of the item response matrix than more complex, polytomous calibrations.

  10. Psychopathy in adolescent offenders: an item response theory study of the antisocial process screening device-self report and the Psychopathy Checklist: Youth Version.

    Science.gov (United States)

    Dillard, Crystal L; Salekin, Randall T; Barker, Edward D; Grimes, Ross D

    2013-04-01

    Few studies have examined the item functioning of youth psychopathy measures or compared the functioning of clinician and self-report based indices. Even fewer studies have made these comparisons in both male and female adolescent samples. The present study examined the applicability of items from two psychopathy measures, the Antisocial Process Screening Device (APSD; Frick, P. J., & Hare, R. D., 2001, The Antisocial Process Screening Device. Toronto, Ontario, Canada: Multi-Health Systems) and Psychopathy Checklist: Youth Version (PCL:YV; Forth, A. E., Kosson, D. S., & Hare, R. D., 2003, The Psychopathy Checklist: Youth Version. Toronto, Ontario, Canada: Multi-Health Systems), to adolescent boys and girls who had come into contact with the law. Item Response Theory was used to test item functioning of the two psychopathy indices. Examination of the Item Response Theory trace lines indicated that the APSD and the PCL:YV have both highly discriminating and poorly discriminating items and that the measures differ in the regions of psychopathy they cover. The PCL:YV is particularly effective at assessing interpersonal and affective features of psychopathy and to a lesser extent, lifestyle and antisocial features. The APSD appears to be effective at assessing narcissism and impulsivity but not callousness. In addition, the items most discriminating of the underlying construct of psychopathy for males and females demonstrate some important differences. These findings suggest that the measures may tap different underlying elements of the same overlaying construct. This may account for modest correlations between the measures. The findings suggest that clinicians should be aware of the regions that each measure best taps and also suggest that continued refinement and revisions to the youth psychopathy measures may be required. PMID:22686465

  11. Computerized Adaptive Testing with Item Clones. Research Report.

    Science.gov (United States)

    Glas, Cees A. W.; van der Linden, Wim J.

    To reduce the cost of item writing and to enhance the flexibility of item presentation, items can be generated by item-cloning techniques. An important consequence of cloning is that it may cause variability on the item parameters. Therefore, a multilevel item response model is presented in which it is assumed that the item parameters of a…

  12. Desenvolvimento de uma escala para medir o potencial empreendedor utilizando a Teoria da Resposta ao Item (TRI Development of a scale to measure the entrepreneurial potential using the Item Response Theory (IRT

    Directory of Open Access Journals (Sweden)

    Luciano Ricardo Rath Alves

    2011-01-01

    Full Text Available Diversas variáveis estão relacionadas ao desenvolvimento da atividade empreendedora, verifica-se, entre elas, a importância do agente empreendedor. Dos estudos que contribuem para o seu entendimento, este segue a linha que defende que o empreendedor tem características e traços de personalidade singulares em relação à população, os quais são propícios ao sucesso do empreendedorismo. O objetivo deste trabalho é desenvolver uma escala para medir o potencial empreendedor utilizando a Teoria da Resposta ao Item. Foi utilizado o modelo logístico de dois parâmetros da TRI. As estimativas dos parâmetros foram obtidas a partir da amostra com 764 pessoas que responderam a um instrumento composto por 103 itens. A curva de informação e do erro padrão do teste e a interpretação qualitativa de níveis da escala permitiram determinar o intervalo mais apropriado para utilização do instrumento. Os resultados mostraram que a escala é mais adequada para avaliar indivíduos com baixo até moderadamente alto potencial empreendedor. Por isso, sugere-se que novos itens sejam incorporados ao instrumento para mensurar e interpretar níveis ainda mais elevados. A Teoria da Resposta ao Item permite que novos itens sejam calibrados a fim de mensurar os empreendedores com alto potencial empreendedor, aproveitando os dados já obtidos.Several variables are related to the development of entrepreneurial activities. An important one among them is the entrepreneurial agent. This study is one of many that contribute to the understanding of the entrepreneurial agent. In its line of thought, it upholds the idea that the entrepreneur has characteristics and personality traits that stand out from the general population and that are favorable to the success of the entrepreneurship. This study aims at developing a measurement scale for entrepreneurial potential using the Item Response Theory. The items were generated by Santos (2008 based on a theoretical model

  13. Development of the Perinatal Depression Inventory (PDI)-14 using item response theory: a comparison of the BDI-II, EPDS, PDI, and PHQ-9.

    Science.gov (United States)

    Brodey, Benjamin B; Goodman, Sherryl H; Baldasaro, Ruth E; Brooks-DeWeese, Amy; Wilson, Melanie Elliott; Brodey, Inger S B; Doyle, Nora M

    2016-04-01

    The objective of this study is to develop a simple, brief, self-report perinatal depression inventory that accurately measures severity in a number of populations. Our team developed 159 Likert-scale perinatal depression items using simple sentences with a fifth-grade reading level. Based on iterative cognitive interviewing (CI), an expert panel improved and winnowed the item pool based on pre-determined criteria. The resulting 67 items were administered to a sample of 628 pregnant and 251 postpartum women with different levels of depression at private and public sector obstetrics clinics, together with the Beck Depression Inventory (BDI-II), Edinburg Postpartum Depression Scale (EPDS), and the Patient Health Questionnaire (PHQ-9), as well as Module A of the Structured Clinical Interview for DSM-IV Diagnoses (SCID). Responses were evaluated using Item Response Theory (IRT). The Perinatal Depression Inventory (PDI)-14 items are highly informative regarding depression severity and function similarly and informatively across pregnant/postpartum, white/non-white, and private-clinic/public-clinic populations. PDI-14 scores correlate well with the PHQ-9, EPDS, and BDI-II, but the PDI-14 provides a more precise measure of severity using far fewer words. The PDI-14 is a brief depression assessment that excels at accurately measuring depression severity across a wide range of severity and perinatal populations. PMID:26271280

  14. Waste minimization concepts applied to oil spill response

    International Nuclear Information System (INIS)

    Lessons learned from past US oil spill response histories show that prudent waste management principles have not been a primary consideration in making decisions for tactical response to major open-water oil spills. Contingency planners (government and industry) consistently choose a mechanical response strategy usually resulting in significant shoreline impact and waste generation (secondary pollution from response actions). Generally, the Environmental Protection Agency's waste minimization hierarchy is not used when managing a major open-water oil spill, subsequent cleanup of oiled shorelines, response to oiled wildlife, and final disposal of oily waste. Contingency plans do not adequately weigh the ecological ramifications from response-generated waste and response-generated pollution when deciding how to protect the environment. This paper shows how the EPA's waste minimization hierarchy should be used during all phases of an oil spill response: strategic planning, tactical planning, and response execution

  15. Examining the Impact of Unscorable Item Responses on the Validity and Interpretability of MMPI-2/MMPI-2-RF Restructured Clinical (RC) Scale Scores

    Science.gov (United States)

    Dragon, Wendy R.; Ben-Porath, Yossef S.; Handel, Richard W.

    2012-01-01

    This article examined the impact of unscorable item responses on the psychometric validity and practical interpretability of scores on the Restructured Clinical (RC) Scales of the Minnesota Multiphasic Personality Inventory-2/Minnesota Multiphasic Personality Inventory-2-Restructured Form (MMPI-2/MMPI-2-RF). In analyses conducted with five…

  16. Evaluation of an Arabic Version of Children's Self-Report Social Skills Scale (CS[superscript 4]) Based on Item Response Theory

    Science.gov (United States)

    Hussein, Mohamed Habashy

    2010-01-01

    The present study examined the psychometric properties of the Arabic version of Children's Self-report Social Skills Scale (CS[superscript 4]) using a generalized partial credit model (GPCM). Data from 722 primary school children (401 boys and 321 girls) responses, in Egypt, were analyzed using GPCM. The results indicated that the 21 items are…

  17. An Item Response Theory Analysis of Harter's Self-Perception Profile for Children or Why Strong Clinical Scales Should Be Distrusted

    Science.gov (United States)

    Egberink, Iris J. L.; Meijer, Rob R.

    2011-01-01

    The authors investigated the psychometric properties of the subscales of the Self-Perception Profile for Children with item response theory (IRT) models using a sample of 611 children. Results from a nonparametric Mokken analysis and a parametric IRT approach for boys (n = 268) and girls (n = 343) were compared. The authors found that most scales…

  18. An item response theory analysis of Harter's Self-Perception Profile for Children or why strong clinical scales should be distrusted

    NARCIS (Netherlands)

    Egberink, Iris J. L.; Meijer, Rob R.

    2011-01-01

    The authors investigated the psychometric properties of the subscales of the Self-Perception Profile for Children with item response theory (IRT) models using a sample of 611 children. Results from a nonparametric Mokken analysis and a parametric IRT approach for boys (n = 268) and girls (n = 343) w

  19. Measuring Student Involvement: A Comparison of Classical Test Theory and Item Response Theory in the Construction of Scales from Student Surveys

    Science.gov (United States)

    Sharkness, Jessica; DeAngelo, Linda

    2011-01-01

    This study compares the psychometric utility of Classical Test Theory (CTT) and Item Response Theory (IRT) for scale construction with data from higher education student surveys. Using 2008 Your First College Year (YFCY) survey data from the Cooperative Institutional Research Program at the Higher Education Research Institute at UCLA, two scales…

  20. Understanding and quantifying cognitive complexity level in mathematical problem solving items

    Directory of Open Access Journals (Sweden)

    SUSAN E. EMBRETSON

    2008-09-01

    Full Text Available The linear logistic test model (LLTM; Fischer, 1973 has been applied to a wide variety of new tests. When the LLTM application involves item complexity variables that are both theoretically interesting and empirically supported, several advantages can result. These advantages include elaborating construct validity at the item level, defining variables for test design, predicting parameters of new items, item banking by sources of complexity and providing a basis for item design and item generation. However, despite the many advantages of applying LLTM to test items, it has been applied less often to understand the sources of complexity for large-scale operational test items. Instead, previously calibrated item parameters are modeled using regression techniques because raw item response data often cannot be made available. In the current study, both LLTM and regression modeling are applied to mathematical problem solving items from a widely used test. The findings from the two methods are compared and contrasted for their implications for continued development of ability and achievement tests based on mathematical problem solving items.

  1. A responsible agenda for applied linguistics: Confessions of a philosopher

    OpenAIRE

    Albert Weideman

    2011-01-01

    When we undertake academic, disciplinary work, we rely on philosophical starting points. Several straightforward illustrations of this can be found in the history of applied linguistics. It is evident from the history of our field that various historically influential approaches to our discipline base themselves upon different academic confessions. This paper examines the effects of basing our applied linguistic work on the idea that applied linguistics is a discipline concerned with design. ...

  2. Waste minimization concepts applied to oil spill response

    International Nuclear Information System (INIS)

    Oil Pollution Act 1990 requires bulk oil cargo vessels and facilities' owners and operators to formulate oil spill response plans for U.S. Coast Guard approval. The industry-based plans should provide specific enhancement to localized, general plans being developed by a team of federal, state, and local agency representatives, including industry participation. This group planning process is referred to as Area Contingency Plans. Although the intensive response planning probably will improve marine oil spill preparedness, current oil spill management practices and regulatory guidelines do not encourage waste minimization - type environmental accountability. This paper provides a waste minimization analysis of the available oil spill response technologies and strategies, offering an environmental management overview on how to best protect the environment after a marine oil spill

  3. A New Extension of the Binomial Error Model for Responses to Items of Varying Difficulty in Educational Testing and Attitude Surveys.

    Directory of Open Access Journals (Sweden)

    James A Wiley

    Full Text Available We put forward a new item response model which is an extension of the binomial error model first introduced by Keats and Lord. Like the binomial error model, the basic latent variable can be interpreted as a probability of responding in a certain way to an arbitrarily specified item. For a set of dichotomous items, this model gives predictions that are similar to other single parameter IRT models (such as the Rasch model but has certain advantages in more complex cases. The first is that in specifying a flexible two-parameter Beta distribution for the latent variable, it is easy to formulate models for randomized experiments in which there is no reason to believe that either the latent variable or its distribution vary over randomly composed experimental groups. Second, the elementary response function is such that extensions to more complex cases (e.g., polychotomous responses, unfolding scales are straightforward. Third, the probability metric of the latent trait allows tractable extensions to cover a wide variety of stochastic response processes.

  4. Harmonization of Neuroticism and Extraversion phenotypes across inventories and cohorts in the Genetics of Personality Consortium:an application of Item Response Theory

    OpenAIRE

    Van den Berg, Stéphanie M.; Marleen H. M. de Moor; McGue, Matt; Pettersson, Erik; Terracciano, Antonio; Verweij, Karin J. H.; Amin, Najaf; Derringer, Jaime; Esko, Tõnu; van Grootheest, Gerard; Hansell, Narelle K.; Huffman, Jennifer; Konte, Bettina; Lahti, Jari; Luciano, Michelle

    2014-01-01

    Mega- or meta-analytic studies (e.g. genome-wide association studies) are increasingly used in behavior genetics. An issue in such studies is that phenotypes are often measured by different instruments across study cohorts, requiring harmonization of measures so that more powerful fixed effect meta-analyses can be employed. Within the Genetics of Personality Consortium, we demonstrate for two clinically relevant personality traits, Neuroticism and Extraversion, how Item-Response Theory (IRT) ...

  5. Developing a Numerical Ability Test for Students of Education in Jordan: An Application of Item Response Theory

    Science.gov (United States)

    Abed, Eman Rasmi; Al-Absi, Mohammad Mustafa; Abu shindi, Yousef Abdelqader

    2016-01-01

    The purpose of the present study is developing a test to measure the numerical ability for students of education. The sample of the study consisted of (504) students from 8 universities in Jordan. The final draft of the test contains 45 items distributed among 5 dimensions. The results revealed that acceptable psychometric properties of the test;…

  6. The D-Optimality Item Selection Criterion in the Early Stage of CAT: A Study with the Graded Response Model

    Science.gov (United States)

    Passos, Valeria Lima; Berger, Martijn P. F.; Tan, Frans E. S.

    2008-01-01

    During the early stage of computerized adaptive testing (CAT), item selection criteria based on Fisher"s information often produce less stable latent trait estimates than the Kullback-Leibler global information criterion. Robustness against early stage instability has been reported for the D-optimality criterion in a polytomous CAT with the…

  7. Digital timing algorithms applied to fast scintillators response

    International Nuclear Information System (INIS)

    The future Facility for Antiproton and Ion Research (FAIR) will house the calorimeter and spectrometer CALIFA, whose design, construction and testing are currently being carried out by the R3B collaboration. The mentioned calorimeter is an array of scintillation detectors displayed in a barrel configuration, which covers the total solid angle. These new fast scintillation materials have been developed in last few years and their main interest lies on their versatility, which allows their use both for applications and fundamental research. In the same way, fast digitizers let the collection of signals at increasingly higher sampling frequencies. Our research takes advantage of these fair properties and is therefore focused on the analysis of digitized pulses for several aims: understanding the behaviour of radiation inside new fast scintillators and the development or improvement of digital algorithms which yield accurate resolution for fast timing and may be also applied to particle identification.

  8. Identifying an efficient set of items sensitive to clinical-range externalizing problems in children.

    Science.gov (United States)

    Petersen, Isaac T; Bates, John E; Dodge, Kenneth A; Lansford, Jennifer E; Pettit, Gregory S

    2016-05-01

    The present study applied item response theory to identify an efficient set of items of the Achenbach Externalizing scale from the Child Behavior Checklist (CBCL; 33 items) and Teacher's Report Form (TRF; 35 items) that were sensitive to clinical-range scores. Mothers and teachers rated children's externalizing problems annually from ages 5 to 13 years in 2 independent samples (Ns = 585 and 1,199). Item properties for each rater across ages 5-8 and 9-13 were examined with item response theory. We identified 10 mother- and teacher-reported items from both samples based on the items' measurement precision for subclinical and clinical levels of externalizing problems: externalizing problems that involve meanness to others, destroying others' things, fighting, lying and cheating, attacking people, screaming, swearing/obscene language, temper tantrums, threatening people, and being loud. Scores on the scales using these items had strong reliability and psychometric properties, capturing nearly as much information as the full Externalizing scale for classifying clinical levels of externalizing problems. Scores on the scale with the 10 CBCL items had moderate accuracy, equivalent to the full Externalizing scale, in classifying diagnoses of conduct disorder based on a research diagnostic interview. Of course, comprehensive clinical assessment would consider additional items, dimensions of behavior, and sources of information, too, but it appears that the behaviors tapped by this select set of items may be core to externalizing psychopathology in children. (PsycINFO Database Record PMID:26322800

  9. Applying Bayesian belief networks in rapid response situations

    Energy Technology Data Exchange (ETDEWEB)

    Gibson, William L [Los Alamos National Laboratory; Deborah, Leishman, A. [Los Alamos National Laboratory; Van Eeckhout, Edward [Los Alamos National Laboratory

    2008-01-01

    The authors have developed an enhanced Bayesian analysis tool called the Integrated Knowledge Engine (IKE) for monitoring and surveillance. The enhancements are suited for Rapid Response Situations where decisions must be made based on uncertain and incomplete evidence from many diverse and heterogeneous sources. The enhancements extend the probabilistic results of the traditional Bayesian analysis by (1) better quantifying uncertainty arising from model parameter uncertainty and uncertain evidence, (2) optimizing the collection of evidence to reach conclusions more quickly, and (3) allowing the analyst to determine the influence of the remaining evidence that cannot be obtained in the time allowed. These extended features give the analyst and decision maker a better comprehension of the adequacy of the acquired evidence and hence the quality of the hurried decisions. They also describe two example systems where the above features are highlighted.

  10. Natural History of Dependency in the Elderly: A 24-Year Population-Based Study Using a Longitudinal Item Response Theory Model.

    Science.gov (United States)

    Edjolo, Arlette; Proust-Lima, Cécile; Delva, Fleur; Dartigues, Jean-François; Pérès, Karine

    2016-02-15

    We aimed to describe the hierarchical structure of Instrumental Activities of Daily Living (IADL) and basic Activities of Daily Living (ADL) and trajectories of dependency before death in an elderly population using item response theory methodology. Data were obtained from a population-based French cohort study, the Personnes Agées QUID (PAQUID) Study, of persons aged ≥65 years at baseline in 1988 who were recruited from 75 randomly selected areas in Gironde and Dordogne. We evaluated IADL and ADL data collected at home every 2-3 years over a 24-year period (1988-2012) for 3,238 deceased participants (43.9% men). We used a longitudinal item response theory model to investigate the item sequence of 11 IADL and ADL combined into a single scale and functional trajectories adjusted for education, sex, and age at death. The findings confirmed the earliest losses in IADL (shopping, transporting, finances) at the partial limitation level, and then an overlapping of concomitant IADL and ADL, with bathing and dressing being the earliest ADL losses, and finally total losses for toileting, continence, eating, and transferring. Functional trajectories were sex-specific, with a benefit of high education that persisted until death in men but was only transient in women. An in-depth understanding of this sequence provides an early warning of functional decline for better adaptation of medical and social care in the elderly. PMID:26825927

  11. Cross-validation study using item response theory: the health-related quality of life for eating disorders questionnaire-short version.

    Science.gov (United States)

    Bilbao, Amaia; Las Hayas, Carlota; Forero, Carlos G; Padierna, Angel; Martin, Josune; Quintana, José M

    2014-08-01

    The Health-Related Quality of Life for Eating Disorder-Short questionnaire is one of the most suitable existing instruments for measuring quality of life in patients with eating disorders. The objective of the study was to evaluate its reliability, validity, and responsiveness in a cohort of 377 patients. A comprehensive validation process was performed, including confirmatory factor analysis and a graded response model, and assessments of reliability and responsiveness at 1 year of follow-up. The confirmatory factor analysis confirmed the two second-order latent traits, social maladjustment, and mental health and functionality. The graded response model results showed that all items were good for discriminating their respective latent traits. Cronbach's alpha coefficients were high, and responsiveness parameters showed moderate changes. In conclusion, this short questionnaire has good psychometric properties. Its simplicity and ease of application further enhance its acceptability and usefulness in clinical research and trials, as well as in routine practice. PMID:24235177

  12. Teoria de Resposta ao Item na análise de uma prova de estatística em universitários Item Response Theory to analyze a statistics test in university students

    Directory of Open Access Journals (Sweden)

    Claudette Maria Medeiros Vendramini

    2005-12-01

    Full Text Available Este estudo objetivou aplicar a Teoria de Resposta ao Item na análise das 15 questões de múltipla escolha de uma prova de estatística apresentada na forma de gráficos ou de tabelas estatísticas. Participaram 413 universitários, selecionados por conveniência, de duas instituições da rede particular de ensino superior, predominantemente do curso de Psicologia (91,5%. Os universitários foram 80% do gênero feminino e do período diurno (69,8%, com idades de 16 a 53 anos, média 24,4 e desvio padrão 7,4. A prova é predominantemente unidimensional e os itens são mais bem ajustados ao modelo logístico de três parâmetros. Os índices de discriminação, dificuldade e correlação bisserial apresentam valores aceitáveis. Os resultados mostram as dificuldades apresentadas pelos estudantes com relação aos conceitos matemáticos e estatísticos, dificuldades essas observadas em outras pesquisas desde o ensino fundamental. Sugere-se que esses conceitos sejam tratados mais profundamente no ensino superior.This study aimed to use the Item Response Theory to analyze the 15 multiple-choice questions of a statistics test presented in the statistics graphics or tables form. The 414 university students were selected by convenience from two private universities, predominantly psychology students (91.5%. The university students were 80% female and with 16-53 years old, mean 24.4 and standard deviation 7.4. The test has predominantly one dimension and the items can be better fitting to the model of three parameters. The indexes of difficulty, discrimination and bisserial correlation presented acceptable values. The results indicate the difficulties of university students in the mathematic and statistic concepts, that difficulties are observed in the other studies since the elementary education. One suggests making more profound studies of these concepts in higher education.

  13. Item response theory in the production of indicators of socioeconomic metropolitan region of Maringá, Paraná State, Brazil - doi: 10.4025/actascitechnol.v34i4.10478

    Directory of Open Access Journals (Sweden)

    Vanessa Rufino da Silva

    2012-10-01

    Full Text Available This study aimed to identify and produce through models of Item Response Theory (IRT a socio-economic indicator based in the items observed in 2000 Census, following the methodology by Soares (2005. By the IRT Methodology, this indicator, as a latent variable, is obtained through the construction of specific models and scales, making it possible to measure this variable, which according to Andrade et al. (2000, IRT analyzes each item which compose the measuring instrument. This case consists of binary or dichotomous items, which assess the possession of certain assets of domestic comfort. The characteristics of each item were analyzed, as the ability to discrimination and income necessary for the possession of certain property. It was concluded that with 13 items, a trustworthy questionnaire can be done for the construction of a socioeconomic index of Maringa’s metropolitan region.

  14. Item Difficulty Modeling of Paragraph Comprehension Items

    Science.gov (United States)

    Gorin, Joanna S.; Embretson, Susan E.

    2006-01-01

    Recent assessment research joining cognitive psychology and psychometric theory has introduced a new technology, item generation. In algorithmic item generation, items are systematically created based on specific combinations of features that underlie the processing required to correctly solve a problem. Reading comprehension items have been more…

  15. Spare Items validation

    International Nuclear Information System (INIS)

    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)

  16. Fuzzy clustering applied to a demand response model in a smart grid contingency scenario

    OpenAIRE

    Pereira, Rita; Fagundes, Andre; Melicio, Rui; Mendes, Victor,; Figueiredo, Joao; Martins, Joao; Quadrado, Jose

    2014-01-01

    This paper focus on a demand response model analysis in a smart grid context considering a contingency scenario. A fuzzy clustering technique is applied on the developed demand response model and an analysis is performed for the contingency scenario. Model considerations and architecture are described. The demand response developed model aims to support consumers decisions regarding their consumption needs and possible economic benefits.

  17. Identifying the ‘red flags’ for unhealthy weight control among adolescents: Findings from an item response theory analysis of a national survey

    Directory of Open Access Journals (Sweden)

    Utter Jennifer

    2012-08-01

    Full Text Available Abstract Background Weight control behaviors are common among young people and are associated with poor health outcomes. Yet clinicians rarely ask young people about their weight control; this may be due to uncertainty about which questions to ask, specifically around whether certain weight loss strategies are healthier or unhealthy or about what weight loss behaviors are more likely to lead to adverse outcomes. Thus, the aims of the current study are: to confirm, using item response theory analysis, that the underlying latent constructs of healthy and unhealthy weight control exist; to determine the ‘red flag’ weight loss behaviors that may discriminate unhealthy from healthy weight loss; to determine the relationships between healthy and unhealthy weight loss and mental health; and to examine how weight control may vary among demographic groups. Methods Data were collected as part of a national health and wellbeing survey of secondary school students in New Zealand (n = 9,107 in 2007. Item response theory analyses were conducted to determine the underlying constructs of weight control behaviors and the behaviors that discriminate unhealthy from healthy weight control. Results The current study confirms that there are two underlying constructs of weight loss behaviors which can be described as healthy and unhealthy weight control. Unhealthy weight control was positively correlated with depressive mood. Fasting and skipping meals for weight loss had the lowest item thresholds on the unhealthy weight control continuum, indicating that they act as ‘red flags’ and warrant further discussion in routine clinical assessments. Conclusions Routine assessments of weight control strategies by clinicians are warranted, particularly for screening for meal skipping and fasting for weight loss as these behaviors appear to ‘flag’ behaviors that are associated with poor mental wellbeing.

  18. Disparities in self-reported geriatric depressive symptoms due to sociodemographic differences: An extension of the bi-factor item response theory model for use in differential item functioning

    OpenAIRE

    Yang, Frances M.; Tommet, Doug; Jones, Richard N.

    2009-01-01

    This study evaluates the measurement noninvariance, or differential item functioning (DIF), in the Center for Epidemiological Studies-Depression (CES-D) items attributable to age, sex, and race/ethnicity among community-dwelling older adults. Participants (N = 2773) were from the New Haven site of the Established Populations for Epidemiologic Studies in the Elderly. Statistical analyses included exploratory factor analysis, bi-factor confirmatory factor analysis, and a bi-factor multiple indi...

  19. Generalized Full-Information Item Bifactor Analysis

    Science.gov (United States)

    Cai, Li; Yang, Ji Seung; Hansen, Mark

    2011-01-01

    Full-information item bifactor analysis is an important statistical method in psychological and educational measurement. Current methods are limited to single-group analysis and inflexible in the types of item response models supported. We propose a flexible multiple-group item bifactor analysis framework that supports a variety of…

  20. Ranking Popular Items By Naive Bayes Algorithm

    Directory of Open Access Journals (Sweden)

    Shiramshetty Gouthami

    2012-03-01

    Full Text Available The problem of ranking popular items is getting increasing interest from a number of research areas. Several algorithms have been proposed for this task. The described problem of ranking and suggesting items arises in diverse applications include interactive computational system for helping people to leverage social information; in technical these systems are called social navigation systems. These social navigation systems help each individual in their performance and decision making over selecting the items. Based on the each individual response the ranking and suggesting of popular items were done. The individual feedback might be obtained by displaying a set of suggested items, where the selection of items is based on the preference of the individual. The aim is to suggest popular items by rapidly studying the true popularity ranking of items. The difficulty in suggesting the true popular items to the users can give emphasis to reputation for some items but may mutilate the resulting item ranking for other items. So the problem of ranking and suggesting items affected many applications including suggestions and search query suggestions for social tagging systems. In this paper we propose Naïve Bayes algorithm for ranking and suggesting popular items.

  1. Applying responsive web design in a small business - case: Satakunnankadun sauna

    OpenAIRE

    Lopez Garcia, Angel

    2013-01-01

    This thesis was created for Innolink Research Oy. The thesis is based on a project that involves the creation of a responsive website for Satakunnankadun sauna, which is a small business owned by Innolink Research Oy. The objective of the thesis is to prove that by applying responsive web design on a small business website such as Satakunnankadun Sauna, it is possible to increase the amount of customers and reve-nues. The project consists of planning, developing and launching a responsive...

  2. Contribution of reactive and proactive control to children's working memory performance: Insight from item recall durations in response sequence planning

    OpenAIRE

    Chevalier, Nicolas; James, Tiffany D.; Wiebe, Sandra A.; Nelson, Jennifer Mize; Espy, Kimberly Andrews

    2014-01-01

    The present study addressed whether developmental improvement in working memory span task performance relies upon a growing ability to proactively plan response sequences during childhood. 213 children completed a working memory span task in which they used a touchscreen to reproduce orally presented sequences of animal names. Children were assessed longitudinally at seven time points between 3 and 10 years of age, and 21 young adults completed the same task. Proactive response sequence plann...

  3. Automated estimation of the truncation of room impulse response by applying a nonlinear decay model.

    Science.gov (United States)

    Janković, Marko; Ćirić, Dejan G; Pantić, Aleksandar

    2016-03-01

    Noise represents one of the most significant disturbances in measured room impulse responses (RIRs), and it has a potentially large impact on evaluation of the decay parameters. In order to reduce noise effects, various methods have been applied, including truncation of an RIR. In this paper, a procedure for the response truncation based on a model of RIR (nonlinear decay model) is presented. The model is represented by an exponential decay plus stationary noise. Unknown parameters of the model are calculated by an optimization that minimizes the difference between the curve generated by the model and the target one of the response to be truncated. Different curves can be applied in the optimization-absolute value of the RIR, logarithmic decay curve, and Schroeder curve obtained by the backward integration of the RIR. The proposed procedure is tested on various synthesized and measured impulse responses. It is compared with the procedure taken from the literature, often applied in practice. PMID:27036242

  4. Obtaining Some Degree of Correspondence Between Unequatable Scores: A Comparison of Item Response Theory and Equipercentile Equating Methods.

    Science.gov (United States)

    Yen, Wendy M.

    Test scores that are not perfectly reliable cannot be strictly equated unless they are strictly parallel. This fact implies that tau equivalence can be lost if an equipercentile equating is applied to observed scores that are not strictly parallel. Thirty-six simulated data sets are produced to simulate equating tests with different difficulties…

  5. 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.

  6. Principles and procedures of considering item sequence effects in the development of calibrated item pools: Conceptual analysis and empirical illustration

    Directory of Open Access Journals (Sweden)

    Safir Yousfi

    2012-12-01

    Full Text Available Item responses can be context-sensitive. Consequently, composing test forms flexibly from a calibrated item pool requires considering potential context effects. This paper focuses on context effects that are related to the item sequence. It is argued that sequence effects are not necessarily a violation of item response theory but that item response theory offers a powerful tool to analyze them. If sequence effects are substantial, test forms cannot be composed flexibly on the basis of a calibrated item pool, which precludes applications like computerized adaptive testing. In contrast, minor sequence effects do not thwart applications of calibrated item pools. Strategies to minimize the detrimental impact of sequence effects on item parameters are discussed and integrated into a nomenclature that addresses the major features of item calibration designs. An example of an item calibration design demonstrates how this nomenclature can guide the process of developing a calibrated item pool.

  7. A Generalized Model with Internal Restrictions on Item Difficulty for Polytomous Items

    Science.gov (United States)

    Wang, Wen-Chung; Jin, Kuan-Yu

    2010-01-01

    In this study, the authors extend the standard item response model with internal restrictions on item difficulty (MIRID) to fit polytomous items using cumulative logits and adjacent-category logits. Moreover, the new model incorporates discrimination parameters and is rooted in a multilevel framework. It is a nonlinear mixed model so that existing…

  8. Development of the Perinatal Depression Inventory (PDI)-14 using item response theory: a comparison of the BDI-II, EPDS, PDI, and PHQ-9

    OpenAIRE

    Brodey, Benjamin B.; Goodman, Sherryl H.; Baldasaro, Ruth E.; Brooks-DeWeese, Amy; Wilson, Melanie Elliott; Brodey, Inger S. B.; Doyle, Nora M.

    2015-01-01

    The objective of this study is to develop a simple, brief, self-report perinatal depression inventory that accurately measures severity in a number of populations. Our team developed 159 Likert-scale perinatal depression items using simple sentences with a fifth-grade reading level. Based on iterative cognitive interviewing (CI), an expert panel improved and winnowed the item pool based on pre-determined criteria. The resulting 67 items were administered to a sample of 628 pregnant and 251 po...

  9. A Comparison of the Approaches of Generalizability Theory and Item Response Theory in Estimating the Reliability of Test Scores for Testlet-Composed Tests

    Science.gov (United States)

    Lee, Guemin; Park, In-Yong

    2012-01-01

    Previous assessments of the reliability of test scores for testlet-composed tests have indicated that item-based estimation methods overestimate reliability. This study was designed to address issues related to the extent to which item-based estimation methods overestimate the reliability of test scores composed of testlets and to compare several…

  10. Reactor calculation in coarse mesh by finite element method applied to matrix response method

    International Nuclear Information System (INIS)

    The finite element method is applied to the solution of the modified formulation of the matrix-response method aiming to do reactor calculations in coarse mesh. Good results are obtained with a short running time. The method is applicable to problems where the heterogeneity is predominant and to problems of evolution in coarse meshes where the burnup is variable in one same coarse mesh, making the cross section vary spatially with the evolution. (E.G.)

  11. Response of vetch, lentil, chickpea and red pea to pre- or post-emergence applied herbicides

    Directory of Open Access Journals (Sweden)

    I. Vasilakoglou

    2013-09-01

    Full Text Available Broad-leaved weeds constitute a serious problem in the production of winter legumes, but few selective herbicides controlling these weeds have been registered in Europe. Four field experiments were conducted in 2009/10 and repeated in 2010/11 in Greece to study the response of common vetch (Vicia sativa L., lentil (Lens culinaris Medik., chickpea (Cicer arietinum L. and red pea (Lathyrus cicera L. to several rates of the herbicides pendimethalin, S-metolachlor, S-metolachlor plus terbuthylazine and flumioxazin applied pre-emergence, as well as imazamox applied post-emergence. Phytotoxicity, crop height, total weight and seed yield were evaluated during the experiments. The results of this study suggest that common vetch, lentil, chickpea and red pea differed in their responses to the herbicides tested. Pendimethalin at 1.30 kg ha-1, S-metolachlor at 0.96 kg ha-1 and flumioxazine at 0.11 kg ha-1 used as pre-emergence applied herbicides provided the least phytotoxicity to legumes. Pendimethalin at 1.98 kg ha-1 and both rates of S-metolachlor plus terbuthylazine provided the greatest common lambsquarters (Chenopodium album L. control. Imazamox at 0.03 to 0.04 kg ha-1 could also be used as early post-emergence applied herbicide in common vetch and red pea without any significant detrimental effect.

  12. Postural responses to anterior and posterior perturbations applied to the upper trunk of standing human subjects.

    Science.gov (United States)

    Colebatch, James G; Govender, Sendhil; Dennis, Danielle L

    2016-02-01

    This study concerned the effects of brisk perturbations applied to the shoulders of standing subjects to displace them either forwards or backwards, our aim being to characterise the responses to these disturbances. Subjects stood on a force platform, and acceleration was measured at the level of C7, the sacrum and both tibial tuberosities. Surface EMG was measured from soleus (SOL), tibialis anterior (TA), the hamstrings (HS), quadriceps (QUAD), rectus abdominis (RA) and lumbar paraspinal (PS) muscles. Trials were recorded for each of four conditions: subjects' eyes open (reference) or closed and on a firm (reference) or compliant surface. Observations were also made of voluntary postural reactions to a tap over the deltoid. Anterior perturbations (mean C7 acceleration 251.7 mg) evoked activity within the dorsal muscles (SOL, HS, PS) with a similar latency to voluntary responses to shoulder tapping. Responses to posterior perturbations (mean C7 acceleration -240.4 mg) were more complex beginning, on average, at shorter latency than voluntary activity (median TA 78.0 ms). There was activation of TA, QUAD and SOL associated with initial forward acceleration of the lower legs. The EMG responses consisted of an initial phasic discharge followed by a more prolonged one. These responses differ from the pattern of automatic postural responses that follow displacements at the level of the ankles, and it is unlikely that proprioceptive afferents excited by ankle movement had a role in the initial responses. Vision and surface properties had only minor effects. Perturbations of the upper trunk evoke stereotyped compensatory postural responses for each direction of perturbation. For posterior perturbations, EMG onset occurs earlier than for voluntary responses. PMID:26487178

  13. Identification of multi-modal plasma responses to applied magnetic perturbations using the plasma reluctance

    Science.gov (United States)

    Logan, Nikolas C.; Paz-Soldan, Carlos; Park, Jong-Kyu; Nazikian, Raffi

    2016-05-01

    Using the plasma reluctance, the Ideal Perturbed Equilibrium Code is able to efficiently identify the structure of multi-modal magnetic plasma response measurements and the corresponding impact on plasma performance in the DIII-D tokamak. Recent experiments demonstrated that multiple kink modes of comparable amplitudes can be driven by applied nonaxisymmetric fields with toroidal mode number n = 2. This multi-modal response is in good agreement with ideal magnetohydrodynamic models, but detailed decompositions presented here show that the mode structures are not fully described by either the least stable modes or the resonant plasma response. This work identifies the measured response fields as the first eigenmodes of the plasma reluctance, enabling clear diagnosis of the plasma modes and their impact on performance from external sensors. The reluctance shows, for example, how very stable modes compose a significant portion of the multi-modal plasma response field and that these stable modes drive significant resonant current. This work is an overview of the first experimental applications using the reluctance to interpret the measured response and relate it to multifaceted physics, aimed towards providing the foundation of understanding needed to optimize nonaxisymmetric fields for independent control of stability and transport.

  14. Aplicação da TRI em uma medida de avaliação da compreensão de leitura Use of the item response theory on a measure for reading comprehension assessment

    Directory of Open Access Journals (Sweden)

    Lucas de Francisco Carvalho

    2013-01-01

    Full Text Available Este trabalho objetivou verificar os parâmetros dos itens e dos sujeitos, por meio da Teoria de Resposta ao Item (TRI, em uma medida de avaliação da compreensão de leitura, englobando análises quantitativas e qualitativas do mapa de itens, assim como investigar a presença de funcionamento diferencial dos itens (DIF. Participaram 518 crianças do 3º, 4º e 5º anos do ensino fundamental, com idades entre 6 e 16 anos, de escolas particular e pública de Belo Horizonte. Utilizou-se um texto elaborado de acordo com a técnica de Cloze. Foi confirmada a unidimensionalidade do instrumento; verificou-se média de theta maior que a média de dificuldade dos itens; e, a presença de DIF foi observada em alguns itens de acordo com os anos de ensino. Tais resultados demonstraram evidências de validade para o instrumento e são discutidos no trabalho.The objective of the present study was to verify the parameters of items and people by using the Item Response Theory (IRT in a reading comprehension measurement, including quantitative and qualitative analyses of the items map as well as to investigate the presence of Differential Item Functioning (DIF. The sample consisted of 518 children from the 3rd, 4th and 5th grades, aged from 6 to 16, from private and public schools in the city of Belo Horizonte-MG. The instrument was a text prepared according to Cloze technique. The data confirmed the unidimensionality of the instrument; showed average theta higher than the average of items; and, the presence of DIF was observed in some items in relation to the school grades. The results demonstrated validity evidence for the instrument and are discussed in this paper.

  15. Research Computer Adaptive Testing Algorithms Based on Item Response Theory%基于项目反应理论的计算机自适应测试算法的研究与实现

    Institute of Scientific and Technical Information of China (English)

    刘锋; 郭维威

    2014-01-01

    With the continuous development of educational testing theory, computer adaptive test has been widely studied and applied, this paper is based on item response theory, using the three-parameter Logistic model to provide a efficient computerized adaptive testing algorithms, thereby to improve the efficiency and accuracy of the test, and finally achieve the evaluation of the ability of candidates.%随着教育测试理论的不断发展,计算机自适应测试得到了广泛的研究与应用,本文在项目反应理论的基础上,采用三参数Logistic模型进行研究,提出了一种有效的计算机自适应测试算法,从而提高测试的效率和准确性,实现对应试者能力水平的估计。

  16. Gibbs sampling method in multidimensional two parameter logistic item response model%多维二参数Logistic项目反应模型的Gibbs抽样法

    Institute of Scientific and Technical Information of China (English)

    付志慧; 李斌

    2014-01-01

    Item response theory (IRT)is based on three assumptions:unidimensionality,local independence and monotonicity.However these assumption has some defects need to be improved.Research shows that use unidimensional model to fit multidimensional data will increase measurement error and make wrong inference to students’ability.Just because of this researchers extend the unidimensional IRT to the multidimensional IRT from different perspectives.Since the multidimensional model has more parameters need to be estimated,traditional methods such as marginal maximum likelihood and Bayes modal estimation procedures are not suitable.However,Gibbs sampler has a great potential to be an efficient and versatile estimation procedure in item response theory.In this article,based on a data augmentation scheme using the Gibbs sampler,we propose a Bayesian procedure to estimate the multidimensional two parameter logistic model (2PLM).With the introduction of latent variable,the full conditional distributions are tractable,and consequently the Gibbs sampling is easy to implement for any prior assumptions.%项目反应理论主要有3个基本假设:单维性,局部独立性和单调性。但是这3个假设存在一些弊端亟待解决。一些科学研究表明,用单维模型来模拟多维测量数据往往会增大测量误差,导致对学生的能力做出不正确的推论。因此,研究者基于各种不同的测验背景,将单维项目反应模型推广到多维项目反应模型。多维项目反应模型涉及到的参数较多,如果采用传统的估计方法,如边际最大似然法和贝叶斯众数估计法处理起来比较困难。然而,在项目反应理论中,Gibbs抽样法可以作为一种高效灵活的估计方法加以应用。基于 Gibbs 抽样的增加数据的技巧,给出了多维二参数 Logistic项目反应模型的Bayes估计方法。随着潜在变量的引入,每个参数的满条件分布都很容易得到,并且不受先

  17. Simulated Annealing Approach Applied to the Energy Resource Management Considering Demand Response for Electric Vehicles

    DEFF Research Database (Denmark)

    Sousa, Tiago; Vale, Zita; Morais, Hugo

    2013-01-01

    The aggregation and management of Distributed Energy Resources (DERs) by an Virtual Power Players (VPP) is an important task in a smart grid context. The Energy Resource Management (ERM) of theses DERs can become a hard and complex optimization problem. The large integration of several DERs...... Simulated Annealing (SA) approach to determine the ERM considering an intensive use of DERs, mainly EVs. In this paper, the possibility to apply Demand Response (DR) programs to the EVs is considered. Moreover, a trip reduce DR program is implemented. The SA methodology is tested on a 32-bus distribution...

  18. Applying Total Physical Response(TPR)Theory to Teaching Chinese Children English

    Institute of Scientific and Technical Information of China (English)

    张院院

    2015-01-01

    Now it has become a fashion in our society that young learners aged from 6 or even younger participate in foreign language learning.With the Second Language Acquisition theories,it is believed that learning a foreign language from the childhood can facilitate the learning.Children need a teaching method which conforms to their psychological and physical characteristics.American psychologist James Asher develops Total Physical Response,which advocates leaning through physical actions.He believes that children should learn a foreign language happily and confidently,just like the process of acquiring their mother tongue.However,Total Physical Response can not be applied effectively in the teaching process due to children’s instincts and characteristics.If there is a way or strategy which takes advantage of children’s characteristics and control their behavior in class,the teaching results would be more satisfying.

  19. Academic freedom and the professional responsibilities of applied ethicists: a comment on Minerva.

    Science.gov (United States)

    Dawson, Angus; Herington, Jonathan

    2014-05-01

    Academic freedom is an important good, but it comes with several responsibilities. In this commentary we seek to do two things. First, we argue against Francesca Minerva's view of academic freedom as presented in her article 'New threats to academic freedom' on a number of grounds. We reject the nature of the absolutist moral claim to free speech for academics implicit in the article; we reject the elitist role for academics as truth-seekers explicit in her view; and we reject a possible more moderate re-construction of her view based on the harm/offence distinction. Second, we identify some of the responsibilities of applied ethicists, and illustrate how they recommend against allowing for anonymous publication of research. Such a proposal points to the wider perils of a public discourse which eschews the calm and careful discussion of ideas. PMID:24724542

  20. Sugarcane Yield Response to Furrow-Applied Organic Amendments on Sand Soils

    Directory of Open Access Journals (Sweden)

    J. Mabry McCray

    2015-01-01

    Full Text Available Organic amendments have been shown to increase sugarcane yield on sand soils in Florida. These soils have very low water and nutrient-holding capacities because of the low content of organic matter, silt, and clay. Because of high costs associated with broadcast application, this field study was conducted to determine sugarcane yield response to furrow application of two organic amendments on sand soils. One experiment compared broadcast application (226 m3 ha−1 of mill mud and yard waste compost, furrow application (14, 28, and 56 m3 ha−1 of these materials, and no amendment. Another experiment compared furrow applications (28 and 56 m3 ha−1 of mill mud and yard waste compost with no amendment. There were significant yield (t sucrose ha−1 responses to broadcast and furrow-applied mill mud but responses to furrow applications were not consistent across sites. There were no significant yield responses to yard waste compost suggesting that higher rates or repeated applications of this amendment will be required to achieve results comparable to mill mud. Results also suggest that enhancing water and nutrient availability in the entire volume of the root zone with broadcast incorporation of organic amendments is the more effective approach for low organic matter sands.

  1. Methodological issues regarding power of classical test theory (CTT and item response theory (IRT-based approaches for the comparison of patient-reported outcomes in two groups of patients - a simulation study

    Directory of Open Access Journals (Sweden)

    Boyer François

    2010-03-01

    Full Text Available Abstract Background Patients-Reported Outcomes (PRO are increasingly used in clinical and epidemiological research. Two main types of analytical strategies can be found for these data: classical test theory (CTT based on the observed scores and models coming from Item Response Theory (IRT. However, whether IRT or CTT would be the most appropriate method to analyse PRO data remains unknown. The statistical properties of CTT and IRT, regarding power and corresponding effect sizes, were compared. Methods Two-group cross-sectional studies were simulated for the comparison of PRO data using IRT or CTT-based analysis. For IRT, different scenarios were investigated according to whether items or person parameters were assumed to be known, to a certain extent for item parameters, from good to poor precision, or unknown and therefore had to be estimated. The powers obtained with IRT or CTT were compared and parameters having the strongest impact on them were identified. Results When person parameters were assumed to be unknown and items parameters to be either known or not, the power achieved using IRT or CTT were similar and always lower than the expected power using the well-known sample size formula for normally distributed endpoints. The number of items had a substantial impact on power for both methods. Conclusion Without any missing data, IRT and CTT seem to provide comparable power. The classical sample size formula for CTT seems to be adequate under some conditions but is not appropriate for IRT. In IRT, it seems important to take account of the number of items to obtain an accurate formula.

  2. 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

    OBJECTIVE: To improve measurement precision, the European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Group is developing an item bank for computerized adaptive testing (CAT) of emotional functioning (EF). The item bank will be within the conceptual framework 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...

  3. Asymmetric Response of Ferroelastic Domain-Wall Motion under Applied Bias.

    Science.gov (United States)

    Jablonski, Michael L; Liu, Shi; Winkler, Christopher R; Damodaran, Anoop R; Grinberg, Ilya; Martin, Lane W; Rappe, Andrew M; Taheri, Mitra L

    2016-02-10

    The switching of domains in ferroelectric and multiferroic materials plays a central role in their application to next-generation computer systems, sensing applications, and memory storage. A detailed understanding of the response to electric fields and the switching behavior in the presence of complex domain structures and extrinsic effects (e.g., defects and dislocations) is crucial for the design of improved ferroelectrics. In this work, in situ transmission electron microscopy is coupled with atomistic molecular dynamics simulations to explore the response of 71° ferroelastic domain walls in BiFeO3 with various orientations under applied electric-field excitation. We observe that 71° domain walls can have intrinsically asymmetric responses to opposing biases. In particular, when the electric field has a component normal to the domain wall, forward and backward domain-wall velocities can be dramatically different for equal and opposite fields. Additionally, the presence of defects and dislocations can strongly affect the local switching behaviors through pinning or nucleation of the domain walls. These results offer insight for controlled ferroelastic domain manipulation via electric-field engineering. PMID:26695346

  4. Sliding Wear Response of a Bronze Bushing: Influence of Applied Load and Test Environment

    Science.gov (United States)

    Prasad, B. K.

    2012-10-01

    This investigation pertains to the examination of the sliding wear behavior of a leaded-tin bronze bushing under the conditions of varying applied loads and test environments against a steel shaft. The test environment was changed by adding 5% of solid lubricants like talc and lead to an oil lubricant separately as well as in combination; the fraction of the two (solid) lubricants within the solid lubricant mixture was varied in the range of 25-75% in the latter case. The wear performance of the bushing was characterized in terms of the wear rate, frictional heating, and friction coefficient. The increasing load led to deterioration in the wear response, while the addition of the solid lubricant particles produced a reverse effect. Further, an appreciable difference in the wear behavior was not observed when the tests were conducted in the oil plus talc and oil plus lead lubricant mixtures. However, the oil containing lead and talc together brought about a significant improvement in the wear response; best results were obtained in the case of the lubricant mixture consisting of lead and talc together in the ratio of 3:1 in the oil. The observed wear behavior of the samples has been discussed in terms of specific characteristics of various microconstituents. The features of the wear surfaces and subsurface regions further substantiated the wear response and enabled us to understand the operating material removal mechanisms.

  5. 用项目反应理论分析自陈量表时最佳模型的选择%Choice of optimal item response model for analysis of self-report questionnaire

    Institute of Scientific and Technical Information of China (English)

    周晶; 郭庆科

    2005-01-01

    log-likelihood with the least items whose mean square residual error were greater than 2, and the volume of test information was greater than that provided by one-parameter model and no less than the three-parameter model. Therefore, the two-parameter logistic model was the best for 2-point scoring model. But the measurement precision of two-parameter Logistic model was lower than that of multi-grade response model.CONCLUSION: When 2-point items are adopted in self-report questionnaire, 2-parameter logistic model can be applied but not 1- or 3-parameter Logistic models. But when the questionnaire uses items that have more than 2 response grades, the measurement precision can be better than that of 2-point data. Merge of the options for the items may result in lowered measurement precision.

  6. Optimal Test Design with Rule-Based Item Generation

    Science.gov (United States)

    Geerlings, Hanneke; van der Linden, Wim J.; Glas, Cees A. W.

    2013-01-01

    Optimal test-design methods are applied to rule-based item generation. Three different cases of automated test design are presented: (a) test assembly from a pool of pregenerated, calibrated items; (b) test generation on the fly from a pool of calibrated item families; and (c) test generation on the fly directly from calibrated features defining…

  7. Modeling Item Response Times with a Two-State Mixture Model: A New Approach to Measuring Speededness. Law School Admission Council Computerized Testing Report. LSAC Research Report Series.

    Science.gov (United States)

    Schnipke, Deborah L.; Scrams, David J.

    Speededness refers to the extent to which time limits affect test takers' performance. With regard to the Law School Admission Test (LSAT), speededness is currently measured by calculating the proportion of test takers who do not reach each item on the test. These proportions typically increase slightly toward the end of the test, indicating that…

  8. Psychometric properties of responses by clinicians and older adults to a 6-item Hebrew version of the Hamilton Depression Rating Scale (HAM-D6)

    DEFF Research Database (Denmark)

    Bachner, Yaacov G; O'Rourke, Norm; Goldfracht, Margalit; Bech, Per; Ayalon, Liat

    2013-01-01

    The Hamilton Depression Rating Scale (HAM-D) is commonly used as a screening instrument, as a continuous measure of change in depressive symptoms over time, and as a means to compare the relative efficacy of treatments. Among several abridged versions, the 6-item HAM-D6 is used most widely in large...

  9. Applying the response matrix method for solving coupled neutron diffusion and transport problems

    International Nuclear Information System (INIS)

    The numerical determination of the flux and power distribution in the design of large power reactors is quite a time-consuming procedure if the space under consideration is to be subdivided into very fine weshes. Many computing methods applied in reactor physics (such as the finite-difference method) require considerable computing time. In this thesis it is shown that the response matrix method can be successfully used as an alternative approach to solving the two-dimension diffusion equation. Furthermore it is shown that sufficient accuracy of the method is achieved by assuming a linear space dependence of the neutron currents on the boundaries of the geometries defined for the given space. (orig.)

  10. Responses of Greenhouse Tomato and Pepper Yields and Nitrogen Dynamics to Applied Compound Fertilizers

    Institute of Scientific and Technical Information of China (English)

    ZHU Jian-Hua; LI Xiao-Lin; ZHANG Fu-Suo; LI Jun-Liang; P.CHRISTIE

    2004-01-01

    Yield and N uptake of tomato (Lycopersicum esculentum Mill.) and pepper (Capsicum annuum L.) crops in five successive rotations receiving two compound fertilizers (12-12-17 and 21-8-11 N-P2O5-K2O) were studied to determine 1)crop responses,2) dynamics of NO3-N and NH4-N in different soil layers,3) N balance and 4) system-level N efficiencies.Five treatments (2 fertilizers,2 fertilizer rates and a control),each with three replicates,were arranged in the study.The higher N fertilizer rate,300 kg N ha-1 (versus 150 kg N ha-i),returned higher vegetable fruit yields and total aboveground N uptake with the largest crop responses occurring for the low-N fertilizer (12-12-17) applied at 300 kg N ha-1 rather than with the high-N fertilizer (21-8-11). Ammonium-N in the top 90 cm of the soil profile declined during the experiment,while nitrate-N remained at a similar level throughout the experiment with the lower rate of fertilizer N.At the higher rate of N fertilizer there was a continuous NO3-N accumulation of over 800 kg N ha-1. About 200 kg N ha-1 was applied with irrigation to each crop using NO3-contaminated groundwater. In general,about 50% of the total N input was recovered from all treatments. Pepper,relative to tomato,used N more efficiently with smaller N losses,but the crops utilized less than 29% of the fertilizer N over the two and a half-year period. Local agricultural practices maintained high residual soil nutrient status. Thus,optimization of irrigation is required to minimize nitrate leaching and maximize crop N recovery.

  11. Was Kiobel Detrimental to Corporate Social Responsibility? Applying Lessons Learnt From American Exceptionalism

    Directory of Open Access Journals (Sweden)

    Benjamin Thompson

    2014-02-01

    Full Text Available The recent decision in the US Supreme Court Kiobel case applied the presumption against extraterritoriality towards the Alien Tort Statute, decreasing the potential scope of tort actions that can be made against corporations for severe human rights violations. In light of the growing influence of multinational corporations and the lack of any international law regime to regulate corporate wrongdoing, this decision might be seen as a blow against one of the few potential avenues for justice for those victims of corporate human rights violations. The Alien Tort Statute is not a jurisdictional statute that allows for claims under international law but is rather a uniquely American cause of action unconnected to international law. The question remains whether an extension of American law to provide remedies for severe corporate human rights abuses can be justified in the absence of any such remedies existent in international law. This article will attempt to answer this question applying criteria developed by leading scholars in response to American exceptionalism. It will argue that the Kiobel decision, rather than being detrimental to holding corporations accountable, actually addresses many of the negative aspects of extraterritorial litigation whilst preserving some possibility of remedy for victims of severe human rights violations by corporations.

  12. The method of averaging applied to pharmacokinetic/pharmacodynamic indirect response models.

    Science.gov (United States)

    Dunne, Adrian; de Winter, Willem; Hsu, Chyi-Hung; Mariam, Shiferaw; Neyens, Martine; Pinheiro, José; Woot de Trixhe, Xavier

    2015-08-01

    The computational effort required to fit the pharmacodynamic (PD) part of a pharmacokinetic/pharmacodynamic (PK/PD) model can be considerable if the differential equations describing the model are solved numerically. This burden can be greatly reduced by applying the method of averaging (MAv) in the appropriate circumstances. The MAv gives an approximate solution, which is expected to be a good approximation when the PK profile is periodic (i.e. repeats its values in regular intervals) and the rate of change of the PD response is such that it is approximately constant over a single period of the PK profile. This paper explains the basis of the MAv by means of a simple mathematical derivation. The NONMEM® implementation of the MAv using the abbreviated FORTRAN function FUNCA is described and explained. The application of the MAv is illustrated by means of an example involving changes in glycated hemoglobin (HbA1c%) following administration of canagliflozin, a selective sodium glucose co-transporter 2 inhibitor. The PK/PD model applied to these data is fitted with NONMEM® using both the MAv and the standard method using a numerical differential equation solver (NDES). Both methods give virtually identical results but the NDES method takes almost 8 h to run both the estimation and covariance steps, whilst the MAv produces the same results in less than 30 s. An outline of the NONMEM® control stream and the FORTRAN code for the FUNCA function is provided in the appendices. PMID:26142076

  13. A Stepwise Test Characteristic Curve Method to Detect Item Parameter Drift

    Science.gov (United States)

    Guo, Rui; Zheng, Yi; Chang, Hua-Hua

    2015-01-01

    An important assumption of item response theory is item parameter invariance. Sometimes, however, item parameters are not invariant across different test administrations due to factors other than sampling error; this phenomenon is termed item parameter drift. Several methods have been developed to detect drifted items. However, most of the…

  14. Building Representative Composite Items

    OpenAIRE

    Leroy, Vincent; Amer-Yahia, Sihem; Gaussier, Eric; Mirisaee, Hamid

    2015-01-01

    The problem of summarizing a large collection of homogeneous items has been addressed extensively in particular in the case of geo-tagged datasets (e.g. Flickr photos and tags). In our work, we study the problem of summarizing large collections of heterogeneous items. For example, a user planning to spend extended periods of time in a given city would be interested in seeing a map of that city with item summaries in different geographic areas, each containing a theater, a gym, a bakery, a few...

  15. Response surface methodology applied to the study of the microwave-assisted synthesis of quaternized chitosan.

    Science.gov (United States)

    Santos, Danilo Martins Dos; Bukzem, Andrea de Lacerda; Campana-Filho, Sérgio Paulo

    2016-03-15

    A quaternized derivative of chitosan, namely N-(2-hydroxy)-propyl-3-trimethylammonium chitosan chloride (QCh), was synthesized by reacting glycidyltrimethylammonium chloride (GTMAC) and chitosan (Ch) in acid medium under microwave irradiation. Full-factorial 2(3) central composite design and response surface methodology (RSM) were applied to evaluate the effects of molar ratio GTMAC/Ch, reaction time and temperature on the reaction yield, average degree of quaternization (DQ¯) and intrinsic viscosity ([η]) of QCh. The molar ratio GTMAC/Ch was the most important factor affecting the response variables and RSM results showed that highly substituted QCh (DQ¯ = 71.1%) was produced at high yield (164%) when the reaction was carried out for 30min. at 85°C by using molar ratio GTMAC/Ch 6/1. Results showed that microwave-assisted synthesis is much faster (≤30min.) as compared to conventional reaction procedures (>4h) carried out in similar conditions except for the use of microwave irradiation. PMID:26794768

  16. Hormonal and neuromuscular responses to mechanical vibration applied to upper extremity muscles.

    Directory of Open Access Journals (Sweden)

    Riccardo Di Giminiani

    Full Text Available OBJECTIVE: To investigate the acute residual hormonal and neuromuscular responses exhibited following a single session of mechanical vibration applied to the upper extremities among different acceleration loads. METHODS: Thirty male students were randomly assigned to a high vibration group (HVG, a low vibration group (LVG, or a control group (CG. A randomized double-blind, controlled-parallel study design was employed. The measurements and interventions were performed at the Laboratory of Biomechanics of the University of L'Aquila. The HVG and LVG participants were exposed to a series of 20 trials ×10 s of synchronous whole-body vibration (WBV with a 10-s pause between each trial and a 4-min pause after the first 10 trials. The CG participants assumed an isometric push-up position without WBV. The outcome measures were growth hormone (GH, testosterone, maximal voluntary isometric contraction during bench-press, maximal voluntary isometric contraction during handgrip, and electromyography root-mean-square (EMGrms muscle activity (pectoralis major [PM], triceps brachii [TB], anterior deltoid [DE], and flexor carpi radialis [FCR]. RESULTS: The GH increased significantly over time only in the HVG (P = 0.003. Additionally, the testosterone levels changed significantly over time in the LVG (P = 0.011 and the HVG (P = 0.001. MVC during bench press decreased significantly in the LVG (P = 0.001 and the HVG (P = 0.002. In the HVG, the EMGrms decreased significantly in the TB (P = 0.006 muscle. In the LVG, the EMGrms decreased significantly in the DE (P = 0.009 and FCR (P = 0.006 muscles. CONCLUSION: Synchronous WBV acutely increased GH and testosterone serum concentrations and decreased the MVC and their respective maximal EMGrms activities, which indicated a possible central fatigue effect. Interestingly, only the GH response was dependent on the acceleration with respect to the subjects' responsiveness.

  17. The NASA Applied Science Program Disasters Area: Disaster Applications Research and Response

    Science.gov (United States)

    Murray, J. J.; Lindsay, F. E.; Stough, T.; Jones, C. E.

    2014-12-01

    The goal of the Natural Disaster Application Area is to use NASA's capabilities in spaceborne, airborne, surface observations, higher-level derived data products, and modeling and data analysis to improve natural disaster forecasting, mitigation, and response. The Natural Disaster Application Area applies its remote sensing observations, modeling and analysis capabilities to provide hazard and disaster information where and when it is needed. Our application research activities specifically contribute to 1) Understanding the natural processes that produce hazards, 2)Developing hazard mitigation technologies, and 3)Recognizing vulnerability of interdependent critical infrastructure. The Natural Disasters Application area selects research projects through a rigorous, impartial peer-review process that address a broad spectrum of disasters which afflict populations within the United States, regionally and globally. Currently there are 19 active projects in the research portfolio which address the detection, characterization, forecasting and response to a broad range of natural disasters including earthquakes, tsunamis, volcanic eruptions and ash dispersion, wildfires, hurricanes, floods, tornado damage assessment, oil spills and disaster data mining. The Disasters team works with federal agencies to aid the government in meeting the challenges associated with natural disaster response and to transfer technologies to agencies as they become operational. Internationally, the Disasters Area also supports the Committee on Earth Observations Working Group on Disasters, and the International Charter on Space and Disasters to increase, strengthen, and coordinate contributions of NASA Earth-observing satellites and applications products to disaster risk management. The CEOS group will lead pilot efforts focused on identifying key systems to support flooding, earthquake, and volcanic events.

  18. Interpretation of differential item functioning analyses using external review

    DEFF Research Database (Denmark)

    Scott, Neil W; Fayers, Peter M; Aaronson, Neil K; Bottomley, Andrew; de Graeff, Alexander; Groenvold, Mogens; Gundy, Chad; Koller, Michael; Petersen, Morten A; Sprangers, Mirjam A G

    2010-01-01

    Differential item functioning (DIF) analyses are used to determine whether certain groups respond differently to a particular item of a test or questionnaire; however, these do not explain the reasons for observed response differences. Many studies have used external reviews of items, sometimes u...

  19. Privacy concerns in responses to sensitive questions: a survey experiment on the influence of numeric codes on unit nonresponse, item nonresponse, and misreporting

    OpenAIRE

    Bader, Felix; Bauer, Johannes; Kroher, Martina; Riordan, Patrick

    2016-01-01

    "Paper-and-pencil surveys are a widely used method for gaining data. Numeric codes printed on the questionnaire are often a prerequisite for the use of scan software, which, in turn, permits a fast and efficient entering of the data from such surveys. However, printed numbers used for optical mark recognition on a questionnaire can provoke concerns about anonymity that may lead to unit nonresponse, item nonresponse, and misreporting. To test this, we conducted an experiment in a mail survey o...

  20. Modelización de una Prueba de Analogías Figurales con la Teoría de Respuesta al Ítem / Modelling Figural Analogies Test with the Item Response Theory

    Directory of Open Access Journals (Sweden)

    G. Diego Blum

    2011-12-01

    Full Text Available The psychometric properties of a Figural Analogies Test are described within the framework of Item Response Theory. Thirty-six 2x2 matrix figures were constructed by using location, distortion and number rules. The sample included 499 psychology students from the University of Buenos Aires, 79% of whom were women. The 3-Parameter Logistic Model was used obtaining a highly satisfactory global fit at 5% (p = .47. Only 3 items did not fit the model. It had good overall discriminatory power (a: M = 1.02, SD = .33, a medium level of difficulty (b: M = -.03, SD = .63 and the c level was slightly lower than expected with six possible answers (c: M = .14, SD = .05. The conditions for modelling the test and possible disadvantages of the present study are discussed.

  1. "Sample-Independent" Item Parameters? An Investigation of the Stability of IRT Item Parameters Estimated from Small Data Sets.

    Science.gov (United States)

    Sireci, Stephen G.

    Whether item response theory (IRT) is useful to the small-scale testing practitioner is examined. The stability of IRT item parameters is evaluated with respect to the classical item parameters (i.e., p-values, biserials) obtained from the same data set. Previous research investigating the effect of sample size on IRT parameter estimation has…

  2. Item Screening in Graphical Loglinear Rasch Models

    DEFF Research Database (Denmark)

    Kreiner, Svend; Christensen, Karl Bang

    2011-01-01

    are used methodically. This paper describes how. It contains a systematic study of the Markov properties and the way they can be used to distinguish spurious from genuine evidence of DIF and local dependence and proposes a strategy for initial item screening that will reduce the time needed to...... identify a graphical loglinear Rasch model that fits the item responses. The last part of the paper illustrates the item screening procedure on simulated data and on data on the PF subscale measuring physical functioning in the SF36 Health Survey inventory....

  3. Applying economic guidelines for responsible tourism in a World Heritage Site

    Directory of Open Access Journals (Sweden)

    Willem J.L. Coetzee

    2008-05-01

    Full Text Available This article proposes an integrated sustainable tourism development strategy for the Vredefort Dome as a World Heritage Site. In particular, it analyses the integration of the South African guidelines for responsible tourism applied to a local community. All tourism product owners in the Dome area formed part of this research that was conducted by means of a survey. The strategy that was formulated for the area aims to ensure that future generations will be able to utilise the resources in the same manner as the present generation. It is indicated that this intra-generational equity will only be possible through an integrated approach. The value of this research is its contribution to responsible tourism and, concurrently, its emphasis on the fact that tourism destinations in South Africa need to be developed in an integrated and sustainable manner.In order for the Vredefort Dome to be a World Heritage Site, and to exist as a protected area, it is imperative that the tourism product owners in the area realise their roles as custodians of this precious site. This proposition leads to the main aim of this study, namely to develop an integrated tourism development strategy for the Vredefort Dome as a World Heritage site.The results of the empirical study indicated that tourism stakeholders are prepared to improve the present situation in the Vredefort Dome and are willing to adjust their business practices in the future. Such changes in practice involve some strategic issues, and the economic, social and environmental strategies will give direction to this World Heritage Site to become more sustainable.

  4. Avertable dose intervention applied in emergency response dose evaluation system for nuclear emergency preparedness in Taiwan

    International Nuclear Information System (INIS)

    In Taiwan the new guides for the nuclear emergency public protective action were laid down by the Atomic Energy Council (AEC) of Executive Yuan, Taiwan, ROC on July 15th, 2005. The main modifications of the guides are that the avertable dose is applied as the intervention levels and suggests the public protective actions. The emergency response dose evaluation system named RPDOSE, which was developed in 2005, was employed in this work to enhance the capability of the avertable dose evaluation for the villages in the emergency planning zone (EPZ). The period of the long-term weather forecasting data was extended from 4 to 8 days to satisfy the requirement of avertable dose computing. According to the intervention levels, the RPDOSE system is used to calculate the avertable dose and suggest appropriate public protective actions such as sheltering, evacuation or iodine prophylaxis as well as the proposed acting times for each village in the EPZ. This system was employed and examined in the annual nuclear emergency exercise of 2008 in the Maanshan nuclear power plant.

  5. Avertable dose intervention applied in emergency response dose evaluation system for nuclear emergency preparedness in Taiwan

    Energy Technology Data Exchange (ETDEWEB)

    Lu Chunghsin, E-mail: chlu@iner.gov.t [Health Physics Division, Institute of Nuclear Energy Research, No. 1000, Wunhua Rd., Jiaan Village, Longtan Township, Taoyuan County 32546, Taiwan (China); Teng Jenhsin [Research and Development Center, Central Weather Bureau, Taiwan (China); Yang Yungmuh; Chang Borjing [Health Physics Division, Institute of Nuclear Energy Research, No. 1000, Wunhua Rd., Jiaan Village, Longtan Township, Taoyuan County 32546, Taiwan (China)

    2010-06-21

    In Taiwan the new guides for the nuclear emergency public protective action were laid down by the Atomic Energy Council (AEC) of Executive Yuan, Taiwan, ROC on July 15th, 2005. The main modifications of the guides are that the avertable dose is applied as the intervention levels and suggests the public protective actions. The emergency response dose evaluation system named RPDOSE, which was developed in 2005, was employed in this work to enhance the capability of the avertable dose evaluation for the villages in the emergency planning zone (EPZ). The period of the long-term weather forecasting data was extended from 4 to 8 days to satisfy the requirement of avertable dose computing. According to the intervention levels, the RPDOSE system is used to calculate the avertable dose and suggest appropriate public protective actions such as sheltering, evacuation or iodine prophylaxis as well as the proposed acting times for each village in the EPZ. This system was employed and examined in the annual nuclear emergency exercise of 2008 in the Maanshan nuclear power plant.

  6. 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

    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......-BREF domains is a more adequate expression of quality of life than the total score of all 26 items. Although none of the subscales are statistically sufficient measures of their domains, the profile scores seem to be adequate approximations to the optimal score....

  7. Item Overexposure in Computerized Classification Tests Using Sequential Item Selection

    Science.gov (United States)

    Huebner, Alan

    2012-01-01

    Computerized classification tests (CCTs) often use sequential item selection which administers items according to maximizing psychometric information at a cut point demarcating passing and failing scores. This paper illustrates why this method of item selection leads to the overexposure of a significant number of items, and the performances of…

  8. Evaluation of Item Candidates: The PROMIS Qualitative Item Review

    OpenAIRE

    DeWalt, Darren A.; Rothrock, Nan; Yount, Susan; Stone, Arthur A.

    2007-01-01

    One of the PROMIS (Patient-Reported Outcome Measurement Information System) network's primary goals is the development of a comprehensive item bank for patient-reported outcomes of chronic diseases. For its first set of item banks, PROMIS chose to focus on pain, fatigue, emotional distress, physical function, and social function. An essential step for the development of an item pool is the identification, evaluation, and revision of extant questionnaire items for the core item pool. In this w...

  9. Consumer satisfaction and item response theory: creating a measurement scale Avaliação do nível de satisfação de alunos de uma instituição de ensino superior: uma aplicação da teoria da resposta ao item

    Directory of Open Access Journals (Sweden)

    Silvana Ligia Vincenzi Bortolotti

    2012-01-01

    Full Text Available Today, people have increasingly demanded more from the state and enterprises. Consumer satisfaction is not an organizational option, but rather a matter of survival for any institution. The quest for measurement of consumer satisfaction has been ongoing in many areas of research, and researchers have concentrated efforts to demonstrate the psychometric quality of their measurements. However, the techniques employed by these commitments have not kept pace with the advances in psychometric theory and methods. The Item Response Theory (IRT is an approach used for assessing latent trait. It is commonly used in educational and psychological tests and provides additional information beyond that obtained from classic psychometric techniques. This article presents a model of cumulative application of item response theory to measure the extent of students' satisfaction with their courses by creating a measurement scale. The Graded Response Model was used. The results demonstrate the effectiveness of this theory in measuring satisfaction since it places both items as individuals on the same scale. This theory may be valuable in the evaluation of customer satisfaction and many other organizational phenomena. The findings may help the decision maker of an enterprise with the correction of flows, processes, and procedures, and, consequently, it may help generate increased efficiency and effectiveness in daily tasks and in event management business. Finally, the information obtained from the analysis can play a role in the development and/or evaluation of institutional planning.O tema deste trabalho é a utilização da Teoria da Resposta ao Item (TRI como ferramenta de avaliação de aspectos organizacionais específicos. O objetivo é aplicar um modelo cumulativo da TRI para criar uma medida de satisfação de alunos com seus cursos, avaliando também a satisfação no ensino e criando uma escala de medida. Muito utilizada nas áreas educacional e psicol

  10. Guideline Implementation: Prevention of Retained Surgical Items.

    Science.gov (United States)

    Fencl, Jennifer L

    2016-07-01

    A surgical item unintentionally retained in a patient after an operative or other invasive procedure is a serious, preventable medical error with the potential to cause the patient great harm. Perioperative RNs play a key role in preventing retained surgical items (RSIs). The updated AORN "Guideline for prevention of retained surgical items" provides guidance for implementing a consistent, multidisciplinary approach to RSI prevention; accounting for surgical items; preventing retention of device fragments; reconciling count discrepancies; and using adjunct technologies to supplement manual count procedures. This article focuses on key points of the guideline to help perioperative personnel provide optimal care during a procedure. Key points addressed include taking responsibility for RSI prevention as a team; minimizing distractions, noise, and interruptions during counts; using consistent counting methods; reconciling discrepancies; and participating in performance-improvement activities. Perioperative RNs should review the complete guideline for additional information and for guidance in writing and updating policies and procedures. PMID:27350354

  11. 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.

  12. Criteria for eliminating items of a Test of Figural Analogies

    Directory of Open Access Journals (Sweden)

    Diego Blum

    2013-12-01

    Full Text Available This paper describes the steps taken to eliminate two of the items in a Test of Figural Analogies (TFA. The main guidelines of psychometric analysis concerning Classical Test Theory (CTT and Item Response Theory (IRT are explained. The item elimination process was based on both the study of the CTT difficulty and discrimination index, and the unidimensionality analysis. The a, b, and c parameters of the Three Parameter Logistic Model of IRT were also considered for this purpose, as well as the assessment of each item fitting this model. The unfavourable characteristics of a group of TFA items are detailed, and decisions leading to their possible elimination are discussed.

  13. Cotton response to poultry litter applied by subsurface banding relative to surface broadcasting

    Science.gov (United States)

    Dry poultry litter is typically land-applied by surface broadcasting, a practice that exposes certain litter nutrients to volatilization loss. Applying litter with a new, experimental implement that places the litter in narrow bands below the soil surface may reduce or eliminate such losses but has...

  14. Effects of Reusing Baseline Volumes of Interest by Applying (Non-)Rigid Image Registration on Positron Emission Tomography Response Assessments

    OpenAIRE

    van Velden, Floris H. P.; Ida A Nissen; Wendy Hayes; Velasquez, Linda M; Hoekstra, Otto S.; Ronald Boellaard

    2014-01-01

    OBJECTIVES: Reusing baseline volumes of interest (VOI) by applying non-rigid and to some extent (local) rigid image registration showed good test-retest variability similar to delineating VOI on both scans individually. The aim of the present study was to compare response assessments and classifications based on various types of image registration with those based on (semi)-automatic tumour delineation. METHODS: Baseline (n = 13), early (n = 12) and late (n = 9) response (after one and three ...

  15. Analyzing the Role of Corporate Social Responsibility on Reputation Building and Image Formation : Case Lapland University of Applied Sciences

    OpenAIRE

    Ghiyaei, Parisa

    2014-01-01

    Today Corporate Social Responsibility (henceforth CSR) is gaining cumulative importance among individuals and corporations. CSR is an umbrella word which covers all responsibilities related to economic, environment, society and ethics. Concepts such as green marketing and sustainability have recently been added under the umbrella of CSR. Lapland University of Applied Sciences (hereinafter Lapland UAS) is interested in building reputation. Therefore, the main objective of the current rese...

  16. 'Forget me (not)?' - Remembering Forget-Items Versus Un-Cued Items in Directed Forgetting.

    Science.gov (United States)

    Zwissler, Bastian; Schindler, Sebastian; Fischer, Helena; Plewnia, Christian; Kissler, Johanna M

    2015-01-01

    Humans need to be able to selectively control their memories. This capability is often investigated in directed forgetting (DF) paradigms. In item-method DF, individual items are presented and each is followed by either a forget- or remember-instruction. On a surprise test of all items, memory is then worse for to-be-forgotten items (TBF) compared to to-be-remembered items (TBR). This is thought to result mainly from selective rehearsal of TBR, although inhibitory mechanisms also appear to be recruited by this paradigm. Here, we investigate whether the mnemonic consequences of a forget instruction differ from the ones of incidental encoding, where items are presented without a specific memory instruction. Four experiments were conducted where un-cued items (UI) were interspersed and recognition performance was compared between TBR, TBF, and UI stimuli. Accuracy was encouraged via a performance-dependent monetary bonus. Experiments varied the number of items and their presentation speed and used either letter-cues or symbolic cues. Across all experiments, including perceptually fully counterbalanced variants, memory accuracy for TBF was reduced compared to TBR, but better than for UI. Moreover, participants made consistently fewer false alarms and used a very conservative response criterion when responding to TBF stimuli. Thus, the F-cue results in active processing and reduces false alarm rate, but this does not impair recognition memory beyond an un-cued baseline condition, where only incidental encoding occurs. Theoretical implications of these findings are discussed. PMID:26635657

  17. Data Visualization of Item-Total Correlation by Median Smoothing

    Science.gov (United States)

    Yu, Chong Ho; Douglas, Samantha; Lee, Anna; An, Min

    2016-01-01

    This paper aims to illustrate how data visualization could be utilized to identify errors prior to modeling, using an example with multi-dimensional item response theory (MIRT). MIRT combines item response theory and factor analysis to identify a psychometric model that investigates two or more latent traits. While it may seem convenient to…

  18. Applying international standards and guidelines on corporate social responsibility: An action plan

    NARCIS (Netherlands)

    Cramer, J.M.

    2005-01-01

    How can a company start the process of corporate social responsibility in an international context, thereby makinge use of diverse standards and guidelines? This question immediately came to the fore emerged after the start of the programme ‘Corporate social responsibility in international context’

  19. 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.

  20. Suggestion of True Popular Items

    Directory of Open Access Journals (Sweden)

    Huidrom Romesh Chandra Singh

    2010-07-01

    Full Text Available Making of suggestion of items using user’s feedback creates some problems in the actual ranking of the items. It populates some items while it suppresses some others. In short, it affects the original popularity of the items. Our goal in this paper is to make a suggestion of the items and rank them according to true/original popularity. We use some ranking and suggesting algorithms in order to achieve our goal. Our result provides a very effective performance which givesa true popularity of the items.

  1. 78 FR 26790 - Summary of Responses To Request for Information (RFI): Opportunities To Apply a Department of...

    Science.gov (United States)

    2013-05-08

    ... Information (RFI): Opportunities To Apply a Department of Health and Human Services Message Library To Advance... Administration, HHS. ACTION: Summary of Responses to Request for Information (RFI). SUMMARY: On January 29, 2013, the Health Resources and Services Administration (HRSA) issued a Request for Information (RFI)...

  2. Influence of applied magnetic field strength and frequency response of pick-up coil on the magnetic barkhausen noise profile

    International Nuclear Information System (INIS)

    The influence of applied magnetic field strength and frequency response of the pick-up coil on the shape of Magnetic Barkhausen Noise (MBN) profile have been studied. The low frequency MBN measurements have been carried out using 5 different MBN pick-up coils at two different ranges of applied magnetic field strengths on quenched and tempered (QT) and case-carburised and tempered (CT) 18CrNiMo7 steel bar samples. The MBN pick-up coils have been designed to obtain different frequency response such that the peak frequency response varies from ∼4 kHz to ∼32 kHz and the amplitude of low frequency signals decreases gradually. At lower applied magnetic field strength of ±14,000 A/m, all the pick-up coils produced a single peak MBN profile for both QT and CT sample. However, at higher applied magnetic field strength of ±22,000 A/m, the MBN profile showed two peaks for both QT and CT samples for pick-up coils with peak frequency response up to ∼17 kHz. Also, there is systematic reduction in peak 2 for QT sample and asymmetric reduction in the heights of peak 1 and peak 2 for CT sample with increase in peak frequency response of the pick-up coils. The decreasing sensitivity of pick-up coils with increasing peak frequency response to MBN signal generation is indicated by the gradual reduction in width of MBN profile and height of peak 2 in the QT sample. The drastic reduction in peak 1 as compared to peak 2 in the CT sample shows the effect of decreasing low frequency response of the pick-up coils on lowering skin-depth of MBN signal detection. This study clearly suggests that it is essential to optimise both maximum applied magnetic field strength and frequency response of the MBN pick-up coil for maximising the shape of the MBN profile for appropriate correlation with the magnetisation process and hence the material properties. - Highlights: • Influence of magnetic field and frequency response of pick-up coil on MBN profile. • Characteristic frequency response

  3. Physics Items and Student's Performance at Enem

    CERN Document Server

    Gonçalves, Wanderley P

    2013-01-01

    The Brazilian National Assessment of Secondary Education (ENEM, Exame Nacional do Ensino M\\'edio) has changed in 2009: from a self-assessment of competences at the end of high school to an assessment that allows access to college and student financing. From a single general exam, now there are tests in four areas: Mathematics, Language, Natural Sciences and Social Sciences. A new Reference Matrix is build with components as cognitive domains, competencies, skills and knowledge objects; also, the methodological framework has changed, using now Item Response Theory to provide scores and allowing longitudinal comparison of results from different years, providing conditions for monitoring high school quality in Brazil. We present a study on the issues discussed in Natural Science Test of ENEM over the years 2009, 2010 and 2011. Qualitative variables are proposed to characterize the items, and data from students' responses in Physics items were analysed. The qualitative analysis reveals the characteristics of the ...

  4. Response surface method applied to optimization of estradiol permeation in chitosan membranes

    Indian Academy of Sciences (India)

    Luciano Mengatto; María I Cabrera; Julio A Luna

    2012-06-01

    The present work deals with the study of estradiol permeation in chitosan membranes. A fractional factorial design was built for the determination of the main factors affecting estradiol permeation. The independent factors analysed were: concentration of chitosan, concentration of cross-linking agent, cross-linking time and thermal treatment. It was found that concentration of chitosan and cross-linking time significantly affected the response. The effects of thermal treatment and concentration of cross-linking agent were not significant. An optimization process based on response surface methodology was carried out in order to develop a statistical model which describes the relationship between active independent variables and estradiol flux. This model can be used to find out a combination of factor levels during response optimization. Possible options for response optimization are to maximize, minimize or move towards a target value.

  5. Spectral response curve models applied to forest cover-type discrimination

    Science.gov (United States)

    Hudson, W. D.; Lusch, D. P.

    1984-01-01

    The potential of remote sensing systems to provide a cost-effective inventory tool in the case of forest resources is currently of interest to a variety of natural resources management agencies. A number of studies have been performed regarding the use of Landsat data for mapping forest resources in Michigan. The present paper is concerned with current research, which has been directed toward the development and evaluation of computer-implemented classifications for the identification and characterization of coniferous forest types in Michigan's northern Lower Peninsula. Attention is given to the characteristic response curves from Landsat MSS data, spectral response curve models, and forest cover-type discrimination. It is found that spectral response curve models can be used to evaluate and explain the characteristic spectral responses of coniferous forest types on a snow-covered, winter Landsat scene.

  6. Bayesian item selection in constrained adaptive testing using shadow tests

    OpenAIRE

    Bernard P. Veldkamp

    2010-01-01

    Application of Bayesian item selection criteria in computerized adaptive testing might result in improvement of bias and MSE of the ability estimates. The question remains how to apply Bayesian item selection criteria in the context of constrained adaptive testing, where large numbers of specifications have to be taken into account in the item selection process. The Shadow Test Approach is a general purpose algorithm for administering constrained CAT. In this paper it is shown how the approac...

  7. IRT Item Parameters and the Reliability and Validity of Pretest, Posttest, and Gain Scores

    Science.gov (United States)

    May, Kim; Jackson, Tameika S.

    2005-01-01

    The effect of different combinations of item response theory (IRT) item parameters (item difficulty, item discrimination, and the guessing probability) on the reliability and construct validity (correlation with the latent trait being measured) of pretest, posttest, and gain scores was analytically examined using the 3-parameter logistic (3PL)…

  8. Intentional Forgetting Reduces Color-Naming Interference: Evidence from Item-Method Directed Forgetting

    Science.gov (United States)

    Lee, Yuh-shiow; Lee, Huang-mou; Fawcett, Jonathan M.

    2013-01-01

    In an item-method-directed forgetting task, Chinese words were presented individually, each followed by an instruction to remember or forget. Colored probe items were presented following each memory instruction requiring a speeded color-naming response. Half of the probe items were novel and unrelated to the preceding study item, whereas the…

  9. Applying international standards and guidelines on corporate social responsibility: An action plan

    OpenAIRE

    Cramer, J.M.

    2005-01-01

    How can a company start the process of corporate social responsibility in an international context, thereby makinge use of diverse standards and guidelines? This question immediately came to the fore emerged after the start of the programme ‘Corporate social responsibility in international context’ programme of the National Initiative for Sustainable Development (NIDO), running which runs from January 2003 – August 2005. The objective of this programme is to concretise, in cooperation with 22...

  10. Response of winter wheat (Triticum aestivum L.) to autumn applied saflufenacil

    OpenAIRE

    Lynette R. Brown; Nader Soltani; Christy Shropshire; Peter H. Sikkema

    2012-01-01

    There is limited information on the effect of saflufenacil application timing when applied in autumn to winter wheat. Five field experiments were conducted over a three-year period (2007- 2009) at two locations (Ridgetown and Exeter, Ontario) to evaluate the tolerance of winter wheat to autumn applications of saflufenacil applied pre-plant (PP), pre-emergence (PRE), or post-emergence (POST) at 25, 50, 100 and 200 g a.i. ha-1. As the dose of saflufenacil increased, the a...

  11. Item Analysis and Differential Item Functioning of a Brief Conduct Problem Screen

    OpenAIRE

    Wu, Johnny; King, Kevin M; Racz, Sarah Jensen; Witkiewitz, Katie; McMahon, Robert J.

    2011-01-01

    Research has shown that boys display higher levels of childhood conduct problems than girls, and Black children display higher levels than White children, but few studies have tested for scalar equivalence of conduct problems across gender and race. The authors conducted a 2-parameter item response theory (IRT) model to examine item characteristics of the Authority Acceptance scale from the Teacher Observation of Classroom Adaptation-Revised (AA-TOCA-R; L. Larsson-Werthamer, S. G. Kellam, & L...

  12. Conscientiousness in the workplace : Applying mixture IRT to investigate scalability and predictive validity

    NARCIS (Netherlands)

    Egberink, I.J.L.; Meijer, R.R.; Veldkamp, B.P.

    2010-01-01

    Mixture item response theory (IRT) models have been used to assess multidimensionality of the construct being measured and to detect different response styles for different groups. In this study a mixture version of the graded response model was applied to investigate scalability and predictive vali

  13. Peer to peer sexual harassment :emerging law as it applies to school building administrators' legal responsibility for prevention and response

    OpenAIRE

    Berlin, Lois F

    1996-01-01

    The purpose of this study was to closely examine relevant case law to determine if a legal argument exists that holds school administrators legally responsible for protecting students from peer to peer sexual harassment, particularly under federal laws. A second purpose of this study was to determine if a theoretical and/or regulatory base is available to support the argument. The research questions for this study were: (1) Does an argument emerge from analysis of appropriat...

  14. 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).

  15. New technologies for item monitoring

    International Nuclear Information System (INIS)

    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)

  16. Item2Vec: Neural Item Embedding for Collaborative Filtering

    OpenAIRE

    Barkan, Oren; Koenigstein, Noam

    2016-01-01

    Many Collaborative Filtering (CF) algorithms are item-based in the sense that they analyze item-item relations in order to produce item similarities. Recently, several works in the field of Natural Language Processing suggested to learn a latent representation of words using neural embedding algorithms. Among them, the Skip-gram with Negative Sampling (SGNS), also known as Word2Vec, was shown to provide state-of-the-art results on various linguistics tasks. In this paper, we show that item-ba...

  17. 项目反应理论下计算机自适应考试系统的设计与实现%The Design and Implementation of Computer Adaptive Testing Based on Item Response Theory

    Institute of Scientific and Technical Information of China (English)

    姜霞; 张晖; 李波

    2014-01-01

    Computer adaptive testing based on the Item Response Theory can choose diffirent questions for examinees according to their abilities and arrange different papers for different examinees , It can estimate the examinees ’ abilities faster and more accurately .This paper describes the procedures of computerized adaptive testing .Research were conducted and corresponding solutions were proposed about the model se -lection, item selection strategies , parameter estimation and other key technologies , making possible the design and development of the computerized adaptive testing system .%项目反应理论下的计算机自适应考试能够根据应试者的实际能力水平选择相应难度的试题,做到因人施测,实现更快、更准地对应试者能力进行估计。对计算机自适应考试施测过程进行了描述,对模型的选择、选题策略、参数估计等关键技术进行研究并提出相应的解决方法,实现了系统的设计与开发。

  18. Responses of mink to auditory stimuli: Prerequisites for applying the ‘cognitive bias’ approach

    DEFF Research Database (Denmark)

    Svendsen, Pernille Maj; Malmkvist, Jens; Halekoh, Ulrich;

    2012-01-01

    The aim of the study was to determine and validate prerequisites for applying a cognitive (judgement) bias approach to assessing welfare in farmed mink (Neovison vison). We investigated discrimination ability and associative learning ability using auditory cues. The mink (n = 15 females) were...... farmed mink in a judgement bias approach would thus appear to be feasible. However several specific issues are to be considered in order to successfully adapt a cognitive bias approach to mink, and these are discussed....

  19. The household responsibility system and social change in rural Guizhou, China: applying a cohort approach

    NARCIS (Netherlands)

    Yuan, J.

    2010-01-01

    Since the introduction of the Household Responsibility System (HRS) in 1978, Chinese rural households have experienced many changes. The HRS allows farming households to organize their own agricultural production on contracted lands, enabling them to work more efficiently and get more benefits compa

  20. AQUATIC ANIMAL RESPIRATION AND COUGH RESPONSE APPLIED TO INNOVATIVE ENVIRONMENTAL BIOMONITORING: A BIBLIOGRAPHY

    Science.gov (United States)

    This bibliography encompasses a body of in-depth technical information on the mechanics and physiology of respiration in aquatic animals (vertebrate and invertebrate). In compiling the bibliography, special emphasis was given to identifying studies that deal with responses of thi...

  1. Corn growth response to elevated CO2 varies with the amount of nitrogen applied

    Science.gov (United States)

    Corn, with C4 photosynthetic carbon metabolism, often has no photosynthetic, growth, or yield response to elevated carbon dioxide concentrations. In C3 species, the yield stimulation at elevated carbon dioxide concentrations often decreases with nitrogen limitation. I tested whether such a nitroge...

  2. GENDER DIFFERENCES IN APPLYING COMPLIMENTS AND COMPLIMENT RESPONSES IN CHINESE CONTEXT

    Institute of Scientific and Technical Information of China (English)

    OuanLihong

    2004-01-01

    The previous research done by the author shows that there exist significant differences between men and women in their realization patterns of compliments and compliment responses. These differences are reflected in the strategies used in complimenting and responding to compliments. Generally, women tend to use more polite strategies than men do. This article will explore these differences from both social and cultural perspectives.

  3. Donor impurity states and related optical response in a lateral coupled dot-ring system under applied electric field

    Energy Technology Data Exchange (ETDEWEB)

    Correa, J.D. [Departamento de Ciencias Básicas, Universidad de Medellín, Medellín (Colombia); Mora-Ramos, M.E. [Centro de Investigación en Ciencias, Instituto de Ciencias Básicas y Aplicadas, Universidad Autonoma del Estado de Morelos, Av. Universidad 1001, CP 62209 Cuernavaca, Morelos (Mexico); Duque, C.A., E-mail: cduque@fisica.udea.edu.co [Grupo de Materia Condensada-UdeA, Instituto de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín (Colombia)

    2015-09-01

    A study on the effects of an externally applied electric field on the linear optical absorption and relative refractive index change associated with transitions between off-center donor impurity states in laterally coupled quantum dot-ring system is reported. Electron states are calculated within the effective mass and parabolic band approximations by means of an exact diagonalization procedure. The states and the optical response in each case show significant sensitivity to the geometrical distribution of confining energies as well as to the strength of the applied field.

  4. Donor impurity states and related optical response in a lateral coupled dot-ring system under applied electric field

    International Nuclear Information System (INIS)

    A study on the effects of an externally applied electric field on the linear optical absorption and relative refractive index change associated with transitions between off-center donor impurity states in laterally coupled quantum dot-ring system is reported. Electron states are calculated within the effective mass and parabolic band approximations by means of an exact diagonalization procedure. The states and the optical response in each case show significant sensitivity to the geometrical distribution of confining energies as well as to the strength of the applied field

  5. Radiation-therapeutic properties of living and killed antitularensis vaccine applied after polysaccharide modulation of immune response

    International Nuclear Information System (INIS)

    The popular conception of modern immunology that the most reliable remedy against tularensis infection is the living antitularensis vaccine is considered. Similar conception exists in the radiobiology, where the radioresistance enhancement with different biological response modifiers is mainly due to the stimulation of the cell mediated immune protection. The comparative study is performed of the radiotherapeutic features of living and killed antitularensis vaccines, applied after polysaccharide stimulation. It is established that the best effect has been observed with the killed antitularensis vaccine applied 14 days before gamma irradiation (cobalt-60, 6.8 Gy). (author)

  6. Dose response of selected ion chambers in applied homogeneous transverse and longitudinal magnetic fields

    International Nuclear Information System (INIS)

    Purpose: The magnetic fields of an integrated MR-Linac system will alter the paths of electrons that produce ions in the ionization chambers. The dose response of selected ion chambers is evaluated in the presence of varying transverse and longitudinal magnetic fields. The investigation is useful in calibration of therapeutic x-ray beams associated with MR-Linac systems. Methods: The Monte Carlo code PENELOPE was used to model the irradiation of NE2571, and PR06C ionization chambers in the presence of a transverse and longitudinal (with respect to the photon beam) magnetic fields of varying magnitude. The long axis of each chamber was simulated both parallel and perpendicular to the incident photon beam for each magnetic field case. The dose deposited in each chamber for each case was compared to the case with zero magnetic field by means of a ratio. The PR06C chamber's response was measured in the presence of a transverse magnetic field with field strengths ranging from 0.0 to 0.2 T to compare to simulated results. Results: The simulations and measured data show that in the presence of a transverse magnetic field there is a considerable dose response (maximum of 11% near 1.0 T in the ion chambers investigated, which depends on the magnitude of magnetic field, and relative orientation of the magnetic field, radiation beam, and ion chamber. Measurements made with the PR06C chamber verify these results in the region of measurement. In contrast, a longitudinal magnetic field produces only a slight increase in dose response (2% at 1.5 T) that rises slowly with increasing magnetic field and is seemingly independent of chamber orientation. Response trends were similar for the two ion chambers and relative orientations considered, but slight variations are present from chamber to chamber. Conclusions: Care must be taken when making ion chamber measurements in a transverse magnetic field. Ion chamber responses vary not only with transverse field strength, but with chamber

  7. Dose response of selected solid state detectors in applied homogeneous transverse and longitudinal magnetic fields

    International Nuclear Information System (INIS)

    Purpose: MR-Linac devices under development worldwide will require standard calibration, commissioning, and quality assurance. Solid state radiation detectors are often used for dose profiles and percent depth dose measurements. The dose response of selected solid state detectors is therefore evaluated in varying transverse and longitudinal magnetic fields for this purpose. Methods: The Monte Carlo code PENELOPE was used to model irradiation of a PTW 60003 diamond detector and IBA PFD diode detector in the presence of a magnetic field. The field itself was varied in strength, and oriented both transversely and longitudinally with respect to the incident photon beam. The long axis of the detectors was oriented either parallel or perpendicular to the photon beam. The dose to the active volume of each detector in air was scored, and its ratio to dose with zero magnetic field strength was determined as the “dose response” in magnetic field. Measurements at low fields for both detectors in transverse magnetic fields were taken to evaluate the accuracy of the simulations. Additional simulations were performed in a water phantom to obtain few representative points for beam profile and percent depth dose measurements. Results: Simulations show significant dose response as a function of magnetic field in transverse field geometries. This response can be near 20% at 1.5 T, and it is highly dependent on the detectors’ relative orientation to the magnetic field, the energy of the photon beam, and detector composition. Measurements at low transverse magnetic fields verify the simulations for both detectors in their relative orientations to radiation beam. Longitudinal magnetic fields, in contrast, show little dose response, rising slowly with magnetic field, and reaching 0.5%–1% at 1.5 T regardless of detector orientation. Water tank and in air simulation results were the same within simulation uncertainty where lateral electronic equilibrium is present and expectedly

  8. 17 CFR 229.512 - (Item 512) Undertakings.

    Science.gov (United States)

    2010-04-01

    ... statement to include any financial statements required by “Item 8.A. of Form 20-F (17 CFR 249.220f)” at the... with Item 1100(c)(1) of Regulation AB (17 CFR 229.1100(c)(1)) shall be deemed to be a new registration... CFR 229.1105), information provided in response to that Item pursuant to Rule 312 of Regulation...

  9. Safety Evaluation for Packaging (onsite) T Plant Canyon Items

    International Nuclear Information System (INIS)

    This safety evaluation for packaging (SEP) evaluates and documents the ability to safely ship mostly unique inventories of miscellaneous T Plant canyon waste items (T-P Items) encountered during the canyon deck clean off campaign. In addition, this SEP addresses contaminated items and material that may be shipped in a strong tight package (STP). The shipments meet the criteria for onsite shipments as specified by Fluor Hanford in HNF-PRO-154, Responsibilities and Procedures for all Hazardous Material Shipments

  10. Calibrating well-being, quality of life and common mental disorder items: psychometric epidemiology in public mental health research

    Science.gov (United States)

    Böhnke, Jan R.; Croudace, Tim J.

    2016-01-01

    Background The assessment of ‘general health and well-being’ in public mental health research stimulates debates around relative merits of questionnaire instruments and their items. Little evidence regarding alignment or differential advantages of instruments or items has appeared to date. Aims Population-based psychometric study of items employed in public mental health narratives. Method Multidimensional item response theory was applied to General Health Questionnaire (GHQ-12), Warwick-Edinburgh Mental Well-being Scale (WEMWBS) and EQ-5D items (Health Survey for England, 2010–2012; n = 19 290). Results A bifactor model provided the best account of the data and showed that the GHQ-12 and WEMWBS items assess mainly the same construct. Only one item of the EQ-5D showed relevant overlap with this dimension (anxiety/depression). Findings were corroborated by comparisons with alternative models and cross-validation analyses. Conclusions The consequences of this lack of differentiation (GHQ-12 v. WEMWBS) for mental health and well-being narratives deserves discussion to enrich debates on priorities in public mental health and its assessment. PMID:26635327

  11. Bayesian item selection in constrained adaptive testing using shadow tests

    NARCIS (Netherlands)

    Veldkamp, Bernard P.

    2010-01-01

    Application of Bayesian item selection criteria in computerized adaptive testing might result in improvement of bias and MSE of the ability estimates. The question remains how to apply Bayesian item selection criteria in the context of constrained adaptive testing, where large numbers of specificati

  12. Bayesian Item Selection in Constrained Adaptive Testing Using Shadow Tests

    Science.gov (United States)

    Veldkamp, Bernard P.

    2010-01-01

    Application of Bayesian item selection criteria in computerized adaptive testing might result in improvement of bias and MSE of the ability estimates. The question remains how to apply Bayesian item selection criteria in the context of constrained adaptive testing, where large numbers of specifications have to be taken into account in the item…

  13. 17 CFR 229.406 - (Item 406) Code of ethics.

    Science.gov (United States)

    2010-04-01

    ... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false (Item 406) Code of ethics. 229... 406) Code of ethics. (a) Disclose whether the registrant has adopted a code of ethics that applies to... code of ethics, explain why it has not done so. (b) For purposes of this Item 406, the term code...

  14. Site response of heterogeneous natural deposits to harmonic excitation applied to more than 100 case histories

    Science.gov (United States)

    Chenari, Reza Jamshidi; Bostani Taleshani, Shirin Aminzadeh

    2016-06-01

    Variation of shear-wave propagation velocity (SWV) with depth was studied by analyzing more than one hundred actual SWV profiles. Linear, power, and hyperbolic variation schemes were investigated to find the most representative form for naturally occurred alluvial deposits. It was found that hyperbolic (asymptotic) variation dominates the majority of cases and it can be reliably implemented in analytical or analytical-numerical procedures. Site response analyses for a one-layer heterogeneous stratum were conducted to find an equivalent homogeneous alternative which simplifies the analysis procedure but does not compromise the accuracy of the resonance and amplification responses. Harmonic average, arithmetic average and mid-value equivalents are chosen from the literature for investigation. Furthermore, full and partial depth averaging schemes were evaluated and compared in order to verify the validity of current practices which rely upon averaging shallow depths, viz., the first 30 m of the strata. Engineering bedrock concept was discussed and the results were compared.

  15. The Umbra Simulation and Integration Framework Applied to Emergency Response Training

    Science.gov (United States)

    Hamilton, Paul Lawrence; Britain, Robert

    2010-01-01

    The Mine Emergency Response Interactive Training Simulation (MERITS) is intended to prepare personnel to manage an emergency in an underground coal mine. The creation of an effective training environment required realistic emergent behavior in response to simulation events and trainee interventions, exploratory modification of miner behavior rules, realistic physics, and incorporation of legacy code. It also required the ability to add rich media to the simulation without conflicting with normal desktop security settings. Our Umbra Simulation and Integration Framework facilitated agent-based modeling of miners and rescuers and made it possible to work with subject matter experts to quickly adjust behavior through script editing, rather than through lengthy programming and recompilation. Integration of Umbra code with the WebKit browser engine allowed the use of JavaScript-enabled local web pages for media support. This project greatly extended the capabilities of Umbra in support of training simulations and has implications for simulations that combine human behavior, physics, and rich media.

  16. Contribution of Reactive and Proactive Control to Children's Working Memory Performance: Insight from Item Recall Durations in Response Sequence Planning

    Science.gov (United States)

    Chevalier, Nicolas; James, Tiffany D.; Wiebe, Sandra A.; Nelson, Jennifer Mize; Espy, Kimberly Andrews

    2014-01-01

    The present study addressed whether developmental improvement in working memory span task performance relies upon a growing ability to proactively plan response sequences during childhood. Two hundred thirteen children completed a working memory span task in which they used a touchscreen to reproduce orally presented sequences of animal names.…

  17. Extensions of the Ordered Response Model Applied to Consumer Valuation of New Products

    OpenAIRE

    Das, J.W.M.

    1995-01-01

    In an ordered response model the observed variable is based upon classifying an unobserved variable into one out of a finite number of intervals forming a dissection of the real line (cf. Amemiya, 1981). This model considers the boundaries of the intervals as (unknown) deterministic parameters, the same for every individual. Terza (1985) extended this through the relaxation of the assumed constancy of the boundaries: he allowed the boundaries to be a linear function of observed explanatory va...

  18. The household responsibility system and social change in rural Guizhou, China: applying a cohort approach

    OpenAIRE

    Yuan, J.

    2010-01-01

    Since the introduction of the Household Responsibility System (HRS) in 1978, Chinese rural households have experienced many changes. The HRS allows farming households to organize their own agricultural production on contracted lands, enabling them to work more efficiently and get more benefits compared to during the collective era. Since the market liberation, the number of enterprises that can absorb the surplus labour has increased, and many men migrate to earn cash. This entails changes in...

  19. Enhancing Radiological Emergency Preparedness and Response in South East Asia Through Applied Training and Capability Development

    International Nuclear Information System (INIS)

    The potential malicious use of high activity radioactive sources remains a security concern for governments and the international community. The Code of Conduct on the Safety and Security of Radioactive Sources recognizes the importance of having in place the expertise, measures and tools to detect, respond to and mitigate the consequences of accidents or malicious acts involving radioactive sources. The Australian Regional Security of Radioactive Sources Project has collaborated with States in South East Asia to enhance their radiological emergency preparedness and response (EPR) capacity to security related incidents involving radioactive sources out of regulatory control. The aim of this collaboration is to improve and maintain the national core technical capabilities to enable an effective and safe response to any security related radiological incident. The main elements of this collaborative approach are: (a) identifying the priority areas for training through needs analysis; (b) strengthening individual professional expertise through a structured approach to training; and (c) enhancing individual agency and national nuclear and radiological EPR arrangements and capabilities. This collaboration has enhanced the sustainable development and implementation of South East Asian States’ national EPR capabilities and arrangements to ensure detection, response and mitigation measures are effective, systematic and well integrated within their national framework. (author)

  20. Selected KSC Applied Physics Lab Responses to Shuttle Processing Measurement Requests

    Science.gov (United States)

    Youngquist, Robert C.

    2010-01-01

    The KSC Applied Physics Lab has been supporting Shuttle Ground Processing for over 20 years by solving problems brought to us by Shuttle personnel. Roughly half of the requests to our lab have been to find ways to make measurements, or to improve on an existing measurement process. This talk will briefly cover: 1) Centering the aft end of the External Tank between the Solid Rocket Boosters; 2) Positioning the GOX Vent Hood over the External Tank; 3) Remote Measurements of External Tank Damage; 4) Strain Measurement in the Orbiter Sling; and 5) Over-center Distance Measurement in an Over-center Mechanism.

  1. Applying Tep Measurements to Assess the Response of Hastelloy to Long Time Aging

    Science.gov (United States)

    Ifergane, S.; Gelbstein, Y.; Dahan, I.; Pinkas, M.; Landau, A.

    2009-03-01

    Hastelloy C-276 service temperature is restricted due to precipitation of the intermetallic compound μ. Time-temperature curves indicate that the highest precipitation rate is obtained at about 870° C. Thermoelectric Power (TEP) measurements were applied to monitor the precipitation kinetics during aging at 870° C. The TEP was found to be well correlated with the amount of μ phase formed during aging and with the reduction in impact energy and ductility. It was demonstrated that TEP measurements could be used to monitor aging of Hastelloy C-276.

  2. Social Responsibility in Research Practice: Engaging applied scientists with the socio-ethical context of their work

    OpenAIRE

    Schuurbiers, D.

    2010-01-01

    How to encourage researchers to critically reflect on the ethical and social dimensions of their work? That is the central research question of this thesis. It starts from the assumption that the neutrality view of the social responsibility of the researcher – the view that researchers have no business with the social and ethical dimensions of their work – has become untenable, at least as far as applied sciences such as nano- and biotechnology are concerned. Instead, this thesis adopts a bro...

  3. Yield responses of maize as influenced by supplemental foliar applied phosphorus under drought stress

    Directory of Open Access Journals (Sweden)

    Zahoor Ahmad

    2015-12-01

    Full Text Available Drought is one of the most serious problems posing a grave threat to cereals production including maize. A field study was conducted to evaluate the effect of foliar applied phosphorus @ 8 kg ha-1 at 8th leaf stage on yield and yield components of four maize hybrids i.e two drought tolerant (6525, 32B33 and two drought sensitive (Hycorn and 31P41 under normal and water stress conditions. RCBD with factorial arrangement were employed to lay out the experiment with a net plot size of 4.75 m x 5 m with three replication at research area of Agronomy, Department of Agronomy, University of Agriculture Faisalabad, Pakistan. The foliar applied phosphorus @ 8 kg ha-1 at 8th leaf stage of maize significantly affect the yield and yield parameters in both drought tolerant and sensitive hybrids. The water stress decreased the 1000-grain weight (21.2%, grain yield (21.3% and biological yield (22.4% as compared to normal irrigation. The both drought tolerant hybrids of maize (6525 and 32B33 performed better than drought sensitive hybrids (Hycorn and 31P41 under normal and water stress conditions.

  4. Stress responses of Calluna vulgaris to reduced and oxidised N applied under 'real world conditions'

    International Nuclear Information System (INIS)

    Effects and implications of reduced and oxidised N, applied under 'real world' conditions, since May 2002, are reported for Calluna growing on an ombrotrophic bog. Ammonia has been released from a 10 m line source generating monthly concentrations of 180-6 μg m-3, while ammonium chloride and sodium nitrate are applied in rainwater at nitrate and ammonium concentrations below 4 mM and providing up to 56 kg N ha-1 year-1 above a background deposition of 10 kg N ha-1 year-1. Ammonia concentrations, >8 μg m-3 have significantly enhanced foliar N concentrations, increased sensitivity to drought, frost and winter desiccation, spring frost damage and increased the incidence of pathogen outbreaks. The mature Calluna bushes nearest the NH3 source have turned bleached and moribund. By comparison the Calluna receiving reduced and oxidised N in rain has shown no significant visible or stress related effects with no significant increase in N status. - Exposure to NH3 reduces stress resistance and increases visible damage in mature Calluna

  5. Improving humanitarian response through an innovative pre-positioning concept : an investigation of how commercial vessels can be used to store and transport relief items

    OpenAIRE

    Wilberg, Kristin Heien; Olafsen, Amund Leinaas

    2013-01-01

    Both the number of natural disasters and the people affected by these disasters have increased substantially during the recent decades. Not only is the frequency higher, but the complexity, severity and magnitude of natural disasters has also increased. This trend, combined with the limited amount of funding provided by donors, has created a critical need for improved humanitarian response systems. Even though logistics has evolved from being seen as a necessary expense to become an important...

  6. Measuring health status in British patients with rheumatoid arthritis: reliability, validity and responsiveness of the short form 36-item health survey (SF-36).

    Science.gov (United States)

    Ruta, D A; Hurst, N P; Kind, P; Hunter, M; Stubbings, A

    1998-04-01

    The objective was to assess the performance of the SF-36 health survey (SF-36) in a sample of patients with rheumatoid arthritis (RA) stratified by functional class. The eight SF-36 subscales and the two summary scales (the physical and mental component scales) were assessed for test retest reliability, construct validity and responsiveness to self-reported change in health. In 233 patients with RA, the SF-36 scales were: reliable (intra-class correlation coefficients 0.76-0.93); correlated with American College of Rheumatology (ACR) core disease activity measures [Spearman r = -0.12 (erythrocyte sedimentation rate) to -0.89 (Modified Health Assessment Questionnaire)]; and responsive to improvements in health (standardized response means 0.27-0.9). The distribution of scores on four of the eight subscales (physical function, role limitations physical, role limitations emotional and social function) was clearly non-Gaussian. Very marked floor effects were noted with the physical function scale, and both ceiling and floor effects with the other three subscales. The two SF-36 physical and mental component summary scales are reliable, valid and responsive measures of health status in patients with RA. Six of the eight subscales meet standards required for comparing groups of patients, and the physical function and general health scales may be suitable for monitoring individuals. The two scales measuring role limitations have poor measurement characteristics. The SF-36 pain and physical function scales may be suitable for use as patient self-assessed measures of pain and physical function within the ACR core disease activity set. PMID:9619895

  7. Sugarcane Yield Response to Furrow-Applied Organic Amendments on Sand Soils

    OpenAIRE

    J. Mabry McCray; Shangning Ji; Leslie E. Baucum

    2015-01-01

    Organic amendments have been shown to increase sugarcane yield on sand soils in Florida. These soils have very low water and nutrient-holding capacities because of the low content of organic matter, silt, and clay. Because of high costs associated with broadcast application, this field study was conducted to determine sugarcane yield response to furrow application of two organic amendments on sand soils. One experiment compared broadcast application (226 m3 ha−1) of mill mud and yard waste co...

  8. Counterfeit and Fraudulent Items - Mitigating the risk

    International Nuclear Information System (INIS)

    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

  9. Response of Triatoma infestans to pour-on cypermethrin applied to chickens under laboratory conditions

    Directory of Open Access Journals (Sweden)

    Ivana Amelotti

    2009-05-01

    Full Text Available This article reports the effects of a pour-on formulation of cypermethrin (6% active ingredient applied to chickens exposed to Triatoma infestans, the main vector of Chagas disease in rural houses of the Gran Chaco Region of South America. This study was designed as a completely random experiment with three experimental groups and five replicates. Third instar nymphs were fed on chickens treated with 0, 1 and 2 cc of the formulation. Nymphs were allowed to feed on the chickens at different time intervals after the insecticide application. Third-instar nymphs fed on treated chickens showed a higher mortality, took less blood during feeding and had a lower moulting rate. The mortality rate was highest seven days after the insecticide solution application and blood intake was affected until 30 days after the application of the solution.

  10. Monte Carlo simulation of the response functions of CdTe detectors to be applied in x-ray spectroscopy

    International Nuclear Information System (INIS)

    In this work, the energy response functions of a CdTe detector were obtained by Monte Carlo (MC) simulation in the energy range from 5 to 160 keV, using the PENELOPE code. In the response calculations the carrier transport features and the detector resolution were included. The computed energy response function was validated through comparison with experimental results obtained with 241Am and 152Eu sources. In order to investigate the influence of the correction by the detector response at diagnostic energy range, x-ray spectra were measured using a CdTe detector (model XR-100T, Amptek), and then corrected by the energy response of the detector using the stripping procedure. Results showed that the CdTe exhibits good energy response at low energies (below 40 keV), showing only small distortions on the measured spectra. For energies below about 80 keV, the contribution of the escape of Cd- and Te-K x-rays produce significant distortions on the measured x-ray spectra. For higher energies, the most important correction is the detector efficiency and the carrier trapping effects. The results showed that, after correction by the energy response, the measured spectra are in good agreement with those provided by a theoretical model of the literature. Finally, our results showed that the detailed knowledge of the response function and a proper correction procedure are fundamental for achieving more accurate spectra from which quality parameters (i.e., half-value layer and homogeneity coefficient) can be determined. - Highlights: • The response function of a CdTe detector was determined by Monte Carlo simulation. • The simulation takes into account all interaction process, the carrier transport and the Gaussian resolution. • The influence of different effects of spectral distortion was investigated. • CdTe detector was applied for x-ray spectroscopy. • The proper correction procedure is needed to achieve realistic x-ray spectra

  11. A price-responsive dispatching strategy for Vehicle-to-Grid: An economic evaluation applied to the case of Singapore

    Science.gov (United States)

    Pelzer, Dominik; Ciechanowicz, David; Aydt, Heiko; Knoll, Alois

    2014-06-01

    Employing electric vehicles as short-term energy storage could improve power system stability and at the same time create a new income source for vehicle owners. In this paper, the economic viability of this concept referred to as Vehicle-to-Grid is investigated. For this purpose, a price-responsive charging and dispatching strategy built upon temporally resolved electricity market data is presented. This concept allows vehicle owners to maximize returns by restricting market participation to profitable time periods. As a case study, this strategy is then applied using the example of Singapore. It is shown that an annual loss of S 1000 resulting from a non-price-responsive strategy as employed in previous works can be turned into a S 130 profit by applying the price-responsive approach. In addition to this scenario, realistic mobility patterns which restrict the temporal availability of vehicles are considered. In this case, profits in the range of S 21-S 121 are achievable. Returns in this order of magnitude are not expected to make Vehicle-to-Grid a viable business case, sensitivity analyses, however, show that improved technical parameters could increase profitability. It is further assumed that employing the price-responsive strategy to other national markets may yield significantly greater returns.

  12. A Formulation of the Mantel-Haenszel Differential Item Functioning Parameter with Practical Implications. Statistical Report. LSAC Research Report Series.

    Science.gov (United States)

    Roussos, Louis A.; Schnipke, Deborah L.; Pashley, Peter J.

    The Mantel-Haenszel (MH) differential item functioning (DIF) parameter for uniform DIF is well defined when item responses follow the two-parameter-logistic (2PPL) item response function (IRF), but not when they follow the three-parameter-logistic (3PL) IRF, the model typically used with multiple choice items. This research report presents a…

  13. Avian response to timber harvesting applied experimentally to manage Cerulean Warbler breeding populations

    Science.gov (United States)

    Sheehan, James; Wood, Petra Bohall; Buehler, David A.; Keyser, Patrick D.; Larkin, Jeffrey L.; Rodewald, Amanda D.; Wigley, T. Bently; Boves, Than J.; George, Gregory A.; Bakermans, Marja H.; Beachy, Tiffany A.; Evans, Andrea; McDermott, Molly E.; Newell, Felicity L.; Perkins, Kelly A.; White, Matthew

    2014-01-01

    Timber harvesting has been proposed as a management tool to enhance breeding habitat for the Cerulean Warbler (Setophaga cerulea), a declining Neotropical–Nearctic migratory songbird that nests in the canopy of mature eastern deciduous forests. To evaluate how this single-species management focus might fit within an ecologically based management approach for multiple forest birds, we performed a manipulative experiment using four treatments (three intensities of timber harvests and an unharvested control) at each of seven study areas within the core Cerulean Warbler breeding range. We collected pre-harvest (one year) and post-harvest (four years) data on the territory density of Cerulean Warblers and six additional focal species, avian community relative abundance, and several key habitat variables. We evaluated the avian and habitat responses across the 3–32 m2 ha−1 residual basal area (RBA) range of the treatments. Cerulean Warbler territory density peaked with medium RBA (∼16 m2 ha−1). In contrast, territory densities of the other focal species were negatively related to RBA (e.g., Hooded Warbler [Setophaga citrina]), were positively related to RBA (e.g., Ovenbird [Seiurus aurocapilla]), or were not sensitive to this measure (Scarlet Tanager [Piranga olivacea]). Some species (e.g., Hooded Warbler) increased with time post-treatment and were likely tied to a developing understory, whereas declines (e.g., Ovenbird) were immediate. Relative abundance responses of additional species were consistent with the territory density responses of the focal species. Across the RBA gradient, greatest separation in the avian community was between early successional forest species (e.g., Yellow-breasted Chat [Icteria virens]) and closed-canopy mature forest species (e.g., Ovenbird), with the Cerulean Warbler and other species located intermediate to these two extremes. Overall, our results suggest that harvests within 10–20 m2 ha−1 RBA yield the largest

  14. Differential Weighting of Items to Improve University Admission Test Validity

    OpenAIRE

    Eduardo Backhoff Escudero; Felipe Tirado Segura; Norma Larrazolo Reyna

    2001-01-01

    This paper gives an evaluation of different ways to increase university admission test criterion-related validity, by differentially weighting test items. We compared four methods of weighting multiple-choice items of the Basic Skills and Knowledge Examination (EXHCOBA): (1) punishing incorrect responses by a constant factor, (2) weighting incorrect responses, considering the levels of error, (3) weighting correct responses, considering the item’s difficulty, based on the Classic Measur...

  15. Characteristics of the excavation response zone as applied to shaft sealing

    International Nuclear Information System (INIS)

    Effective sealing of an underground repository requires high quality seals. Clay-based backfills in combination with cement plugs are the possible candidates. An important component of the shaft sealing program is the development of techniques to predict and monitor the flow in the excavation response zone (ERZ) and at the seal-rock interface. The mechanical and hydraulic performance of the seal and backfill and the flow characteristics of the ERZ under in situ conditions will be tested in three experimental shafts to be excavated in the URL. The use of the vacuum permeability technique for characterization of the hydraulic properties and of the permeability distribution in the ERZ under various geomechanical conditions is discussed

  16. EPR response characterization of drugs excipients for applying in accident dosimetry

    International Nuclear Information System (INIS)

    Some drugs are widely used by the population and can be employed to dose retrospective. The carbohydrates (saccharides), commonly used as excipients in the pharmaceutical industry, produce a quantity of free radicals after gamma irradiation, making them useful for dosimetry in emergency or accident situations that imply in dose evaluation from the materials found nearly or in contact with victims. In general, EPR signal from pulverized pills of some drugs are very complex due to the variety of components in the formulation. Because of this fact, some pharmaceutical excipients identified in the pill composition were also analysed by EPR spectrometry. On the counter drugs were studied: Cebion glucose, AAS, Aspirina, Conmel, Lacto-Purga and sugar substitutive ZeroCal. The excipients were: lactose, amide, anhydrous glucose and magnesium stearate. In some samples the number of radicals produced increased with the dose, showing a linear response for a dose range of interest and an adequate sensibility for dosimetry in accident cases

  17. A Comparison of Four Differential Item Functioning Procedures in the Presence of Multidimensionality

    Science.gov (United States)

    Bastug, Özlem Yesim Özbek

    2016-01-01

    Differential item functioning (DIF), or item bias, is a relatively new concept. It has been one of the most controversial and the most studied subject in measurement theory. DIF occurs when people who have the same ability level but from different groups have a different probability of a correct response. According to Item Response Theory (IRT),…

  18. Response surface methodology applied to Supercritical Fluid Extraction (SFE) of carotenoids from Persimmon (Diospyros kaki L.).

    Science.gov (United States)

    Zaghdoudi, Khalil; Framboisier, Xavier; Frochot, Céline; Vanderesse, Régis; Barth, Danielle; Kalthoum-Cherif, Jamila; Blanchard, Fabrice; Guiavarc'h, Yann

    2016-10-01

    Supercritical carbon dioxide with ethanol as co-solvent was used to extract carotenoids from persimmon fruits (Diospyros kaki L.). Based on a response surface methodology (RSM), a predicting model describing the effects of CO2 temperature, pressure, flow rate, ethanol percentage and extraction time was set up for each of the four carotenoids of interest. The best extraction yields in our experimental domain were found at 300 bars, 60°C, 25% (w/w) ethanol, 3mL/min flow rate and 30min for xanthophylls (all-trans-lutein, all-trans-zeaxanthin and all-trans-β-cryptoxanthin). The yields were 15.46±0.56, 16.81±1.74 and 33.23±2.91μg/g of persimmon powder for all-trans-lutein, all-trans-zeaxanthin and all-trans-β-cryptoxanthin, respectively. As a non-oxygenated carotenoid, all-trans-β-carotene was better extracted using 100 bars, 40°C, 25% (w/w) ethanol, 1mL/min flow rate and 30min extraction time, with an extraction yield of 11.19±0.47μg/g of persimmon powder. PMID:27132842

  19. Teste de Raciocínio Auditivo Musical (RAu: estudo inicial por meio da Teoria de Reposta ao Item Test de Raciocinio Auditivo Musical (RAu: estudio inicial a través de la Teoría de Repuesta al Ítem Auditory Musical Reasoning Test: an initial study with Item Response Theory

    Directory of Open Access Journals (Sweden)

    Fernando Pessotto

    2012-12-01

    ón entre los grupos de músicos y no músicos. Los datos encontrados apuntan evidencias de que los ítems miden una dimensión principal (alfa=0,92 con alta capacidad para diferenciar los grupos de músicos profesionales, aficionados y laicos obteniéndose un coeficiente de validez de criterio de r=0,68. Los resultados indican evidencias positivas de precisión y validez para el RAu.This study investigated internal structure and criterion validity of a test that aims at assessing auditory processing of musical ability (Auditory Musical Reasoning Test, RAu. 162 people of both sexes were evaluated, 56.8% men, aged between 15 and 59 years of age (M=27.5; SD=9.01. Participants were divided among musicians (N=24, amateurs (N=62 and lay people (N=76 according to the extension of their knowledge in music. Full Information Item Factor Analysis verified the dimensionality of the instrument and also the properties of the items via Item Response Theory (IRT. Furthermore, we sought to identify the ability to discriminate between professional musicians, amateurs and lay people. Data showed evidence that the items measure a major dimension (alpha=.92 with high ability to differentiate groups of musicians, amateurs and lay people giving a criterion validity coefficient of r=.68. The results indicate positive evidence of reliability and validity for RAu test.

  20. Computerized adaptive testing with item cloning

    NARCIS (Netherlands)

    Glas, Cees A.W.; Linden, van der Wim J.

    2003-01-01

    To increase the number of items available for adaptive testing and reduce the cost of item writing, the use of techniques of item cloning has been proposed. An important consequence of item cloning is possible variability between the item parameters. To deal with this variability, a multilevel item

  1. 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)

  2. Physical protection: threat response and performance goals as applied at the nuclear material inspection and storage (NMIS) building

    International Nuclear Information System (INIS)

    Only one aspect of nuclear security has been discussed here, a disciplined approach to physical protection systems (PPS) design. The best security against a multitude of threats to the nuclear industry is a dynamic and multifaceted safeguards program. It is one that combines PPS design with employee screening, reliability or behavioral observation programs, procedural control, assessment techniques, response capabilities, and security hardware. To be effective, such a program must be supported by management and applied uniformly to all personnel, including the safeguards and security staff

  3. Implementing and operating the Hanford Environmental Information System and applying it to the carbon tetrachloride expedited response action

    International Nuclear Information System (INIS)

    To manage waste and perform environmental monitoring and restoration at the 1450-square kilometer (560-square mile) Hanford Site in southeastern Washington State, vast amounts of scientific and technical data are being generated from sampling. This paper provides an overview of the Hanford Environmental Information System (HEIS), a computerized system designed and implemented to manage the Site's environmental sampling data, lessons learned from putting HEIS into operation, and how HEIS is being applied to the carbon tetrachloride expedited response action being performed at the Site

  4. Three controversies over item disclosure in medical licensure examinations

    Directory of Open Access Journals (Sweden)

    Yoon Soo Park

    2015-09-01

    Full Text Available In response to views on public's right to know, there is growing attention to item disclosure – release of items, answer keys, and performance data to the public – in medical licensure examinations and their potential impact on the test's ability to measure competence and select qualified candidates. Recent debates on this issue have sparked legislative action internationally, including South Korea, with prior discussions among North American countries dating over three decades. The purpose of this study is to identify and analyze three issues associated with item disclosure in medical licensure examinations – 1 fairness and validity, 2 impact on passing levels, and 3 utility of item disclosure – by synthesizing existing literature in relation to standards in testing. Historically, the controversy over item disclosure has centered on fairness and validity. Proponents of item disclosure stress test takers’ right to know, while opponents argue from a validity perspective. Item disclosure may bias item characteristics, such as difficulty and discrimination, and has consequences on setting passing levels. To date, there has been limited research on the utility of item disclosure for large scale testing. These issues requires ongoing and careful consideration.

  5. Three controversies over item disclosure in medical licensure examinations.

    Science.gov (United States)

    Park, Yoon Soo; Yang, Eunbae B

    2015-01-01

    In response to views on public's right to know, there is growing attention to item disclosure - release of items, answer keys, and performance data to the public - in medical licensure examinations and their potential impact on the test's ability to measure competence and select qualified candidates. Recent debates on this issue have sparked legislative action internationally, including South Korea, with prior discussions among North American countries dating over three decades. The purpose of this study is to identify and analyze three issues associated with item disclosure in medical licensure examinations - 1) fairness and validity, 2) impact on passing levels, and 3) utility of item disclosure - by synthesizing existing literature in relation to standards in testing. Historically, the controversy over item disclosure has centered on fairness and validity. Proponents of item disclosure stress test takers' right to know, while opponents argue from a validity perspective. Item disclosure may bias item characteristics, such as difficulty and discrimination, and has consequences on setting passing levels. To date, there has been limited research on the utility of item disclosure for large scale testing. These issues requires ongoing and careful consideration. PMID:26374693

  6. Automatic Association of News Items.

    Science.gov (United States)

    Carrick, Christina; Watters, Carolyn

    1997-01-01

    Discussion of electronic news delivery systems and the automatic generation of electronic editions focuses on the association of related items of different media type, specifically photos and stories. The goal is to be able to determine to what degree any two news items refer to the same news event. (Author/LRW)

  7. The 18 Household Food Security Survey items provide valid food security classifications for adults and children in the Caribbean

    OpenAIRE

    Nunes Cheryl; Gulliford Martin C; Rocke Brian

    2006-01-01

    Abstract Background We tested the properties of the 18 Household Food Security Survey (HFSS) items, and the validity of the resulting food security classifications, in an English-speaking middle-income country. Methods Survey of primary school children in Trinidad and Tobago. Parents completed the HFSS. Responses were analysed for the 10 adult-referenced items and the eight child-referenced items. Item response theory models were fitted. Item calibrations and subject scores from a one-paramet...

  8. The ITER 3D Magnetic Diagnostic Response to Applied n=3 and n=4 RMP's

    Energy Technology Data Exchange (ETDEWEB)

    Lazerson, S A [PPPL

    2014-09-01

    The ITER magnetic diagnostic response to applied n=3 and n=4 RMPs has been calculated for the 15MA scenario. The VMEC code was utilized to calculate free boundary 3D ideal MHD equilibria, where the non-stellarator symmetric terms were included in the calculation. This allows an assessment to be made of the possible boundary displacements due to RMP application in ITER. As the VMEC code assumes a continuous set of nested flux surface, the possibility of island and stochastic region formation is ignored. At the start of the current at-top (L-Mode) application of n = 4 RMP's indicates approximately 1 cm peak-to-peak displacements on the low field side of the plasma while later in the shot (H-mode) perturbations as large as 3 cm are present. Forward modeling of the ITER magnetic diagnostics indicates significant non-axisymmetric plasma response, exceeding 10% the axisymmetric signal in many of the flux loops. Magnetic field probes seem to indicate a greater robustness to 3D effects but still indicate large sensitivities to 3D effects in a number of sensors. Forward modeling of the diagnostics response to 3D equilibria allows assessment of diagnostics design and control scenarios.

  9. Item response times in computerized adaptive testing

    OpenAIRE

    LUTZ F. HORNKE

    2000-01-01

    Tiempos de respuesta al ítem en tests adaptativos informatizados. Los tests adaptativos informatizados (TAI) proporcionan puntuaciones y a la vez tiempos de respuesta a los ítems. La investigación sobre el significado adicional que se puede obtener de la información contenida en los tiempos de respuesta es de especial interés. Se dispuso de los datos de 5912 jóvenes en un test adaptativo informatizado. Estudios anteriores indican mayores tiempos de respuesta cuan...

  10. Nonparametric Cognitive Diagnosis:A Cluster Diagnostic Method Based on Grade Response Items%非参数认知诊断方法:多级评分的聚类分析

    Institute of Scientific and Technical Information of China (English)

    康春花; 任平; 曾平飞

    2015-01-01

    基于属性合分和聚类分析的思想提出了适用于多级评分的聚类分析方法,同时探讨了属性层次结构、样本容量和失误率对该方法判准率的影响。研究发现:(1)该方法在各种试验情境下均有较高的模式判准率和边际判准率;(2)判准率不依赖样本容量的大小,使其可适用于小型测评及课堂评估;(3)判准率受属性层次紧密度影响较小;(4)该方法在实践情境中表现出较好的内外部效度。%Examinations help students learn more efficiently by filling their learning gaps. To achieve this goal, we have to differentiate students who have from those who have not mastered a set of attributes as measured by the test through cognitive diagnostic assessment. K-means cluster analysis, being a nonparametric cognitive diagnosis method requires the Q-matrix only, which reflects the relationship between attributes and items. This does not require the estimation of the parameters, so is independent of sample size, simple to operate, and easy to understand. Previous research use the sum score vectors or capability scores vector as the clustering objects. These methods are only adaptive for dichotomous data. Structural response items are, however, the main type used in examinations, particularly as required in recent reforms. On the basis of previous research, this paper puts forward a method to calculate a capability matrix reflecting the mastery level on skills and is applicable to grade response items. Our study included four parts. First, we introduced the K-means cluster diagnosis method which has been adapted for dichotomous data. Second, we expanded the K-means cluster diagnosis method for grade response data (GRCDM). Third, in Part Two, we investigated the performance of the method introduced using a simulation study. Fourth, we investigated the performance of the method in an empirical study. The simulation study focused on three factors. First, the sample size was

  11. Development of an item bank for computerized adaptive test (CAT) measurement of pain

    DEFF Research Database (Denmark)

    Petersen, Morten Aa; Aaronson, Neil K; Chie, Wei-Chu; Conroy, Thierry; Costantini, Anna; Hammerlid, Eva; Hjermstad, Marianne J; Kaasa, Stein; Loge, Jon H; Velikova, Galina; Young, Teresa; Groenvold, Mogens

    2016-01-01

    by the EORTC QLQ-C30 questionnaire. METHODS: The development process consisted of four steps: (1) literature search, (2) formulation of new items and expert evaluations, (3) pretesting and (4) field-testing and psychometric analyses for the final selection of items. RESULTS: In step 1, we identified...... 337 pain items from the literature. Twenty-nine new items fitting the QLQ-C30 item style were formulated in step 2 that were reduced to 26 items by expert evaluations. Based on interviews with 31 patients from Denmark, France and the UK, the list was further reduced to 21 items in step 3. In phase 4......, responses were obtained from 1103 cancer patients from five countries. Psychometric evaluations showed that 16 items could be retained in a unidimensional item bank. Evaluations indicated that use of the CAT measure may reduce sample size requirements with 15-25 % compared to using the QLQ-C30 pain scale...

  12. OSL and Tl response characterization of micro LiF:Mg, Ti dosimeters to be applied to VMAT quality assurance

    Energy Technology Data Exchange (ETDEWEB)

    Bravim, A.; Campos, L. L. [Instituto de Pesquisas Energeticas e Nucleares / CNEN, Av. Lineu Prestes 2242, Cidade Universitaria, 05508-000 Sao Paulo (Brazil); Sakuraba, R. K.; Da Cruz, J. C., E-mail: ambravim@hotmail.com [Sociedade Beneficente Israelita Brasileira - Hospital Albert Einstein, Av. Albert Einstein 627/701, Jardim Leonor, 05652-900 Sao Paulo (Brazil)

    2014-08-15

    VMAT Rapid Arc is a new method of treatment responsible for a change in the setting of radiotherapy, bringing benefits and allowing a lower toxicity in the treatment of patients. With this treatment is possible to minimize the radiation dose to the healthy tissues and escalate the dose to the target volume (tumor) (Hall, 1998; Mundt, 2005; Bortfeld, 2006). The quality assurance is essential to verify the operation of all components involved in the process of treatment planning and dose delivery. Several organizations recommended the verification of patient dose for quality improvement in radiotherapy and the recommended maximum values for the uncertainty in the dose range of ± 5% (ICRU, 1976, AAPM, 1983). This paper aims to evaluate the feasibility of applying LiF:Mg,Ti micro dosimeters as a new method of dosimetry to VMAT Rapid Arc. (Author)

  13. Applying Physically Representative Watershed Modelling to Assess Peak and Low Flow Response to Timber Harvest: Application for Watershed Assessments

    Science.gov (United States)

    MacDonald, R. J.; Anderson, A.; Silins, U.; Craig, J. R.

    2014-12-01

    Forest harvesting, insects, disease, wildfire, and other disturbances can combine with climate change to cause unknown changes to the amount and timing of streamflow from critical forested watersheds. Southern Alberta forest and alpine areas provide downstream water supply for agriculture and water utilities that supply approximately two thirds of the Alberta population. This project uses datasets from intensely monitored study watersheds and hydrological model platforms to extend our understanding of how disturbances and climate change may impact various aspects of the streamflow regime that are of importance to downstream users. The objectives are 1) to use the model output of watershed response to disturbances to inform assessments of forested watersheds in the region, and 2) to investigate the use of a new flexible modelling platform as a tool for detailed watershed assessments and hypothesis testing. Here we applied the RAVEN hydrological modelling framework to quantify changes in key hydrological processes driving peak and low flows in a headwater catchment along the eastern slopes of the Canadian Rocky Mountains. The model was applied to simulate the period from 2006 to 2011 using data from the Star Creek watershed in southwestern Alberta. The representation of relevant hydrological processes was verified using snow survey, meteorological, and vegetation data collected through the Southern Rockies Watershed Project. Timber harvest scenarios were developed to estimate the effects of cut levels ranging from 20 to 100% over a range of elevations, slopes, and aspects. We quantified changes in the timing and magnitude of low flow and high flow events during the 2006 to 2011 period. Future work will assess changes in the probability of low and high flow events using a long-term meteorological record. This modelling framework enables relevant processes at the watershed scale to be accounted in a physically robust and computational efficient manner. Hydrologic

  14. A Classical Test Theory Perspective on LSAT Local Item Dependence. LSAC Research Report Series. Statistical Report.

    Science.gov (United States)

    Reese, Lynda M.

    This study extended prior Law School Admission Council (LSAC) research related to the item response theory (IRT) local item independence assumption into the realm of classical test theory. Initially, results from the Law School Admission Test (LSAT) and two other tests were investigated to determine the approximate state of local item independence…

  15. Item Characteristic Curve Parameters: Effects of Sample Size on Linear Equating.

    Science.gov (United States)

    Ree, Malcom James; Jensen, Harald E.

    By means of computer simulation of test responses, the reliability of item analysis data and the accuracy of equating were examined for hypothetical samples of 250, 500, 1000, and 2000 subjects for two tests with 20 equating items plus 60 additional items on the same scale. Birnbaum's three-parameter logistic model was used for the simulation. The…

  16. Bootstrap Standard Errors for Maximum Likelihood Ability Estimates When Item Parameters Are Unknown

    Science.gov (United States)

    Patton, Jeffrey M.; Cheng, Ying; Yuan, Ke-Hai; Diao, Qi

    2014-01-01

    When item parameter estimates are used to estimate the ability parameter in item response models, the standard error (SE) of the ability estimate must be corrected to reflect the error carried over from item calibration. For maximum likelihood (ML) ability estimates, a corrected asymptotic SE is available, but it requires a long test and the…

  17. Selection of unidimensional scales from a multidimensional item bank in the polytomous Mokken IRT model

    NARCIS (Netherlands)

    Hemker, BT; Sijtsma, Klaas; Molenaar, Ivo W

    1995-01-01

    An automated item selection procedure for selecting unidimensional scales of polytomous items from multidimensional datasets is developed for use in the context of the Mokken item response theory model of monotone homogeneity (Mokken & Lewis, 1982). The selection procedure is directly based on the s

  18. A Markov Chain Monte Carlo Approach to Confirmatory Item Factor Analysis

    Science.gov (United States)

    Edwards, Michael C.

    2010-01-01

    Item factor analysis has a rich tradition in both the structural equation modeling and item response theory frameworks. The goal of this paper is to demonstrate a novel combination of various Markov chain Monte Carlo (MCMC) estimation routines to estimate parameters of a wide variety of confirmatory item factor analysis models. Further, I show…

  19. The Asymptotic Distribution of Ability Estimates: Beyond Dichotomous Items and Unidimensional IRT Models

    Science.gov (United States)

    Sinharay, Sandip

    2015-01-01

    The maximum likelihood estimate (MLE) of the ability parameter of an item response theory model with known item parameters was proved to be asymptotically normally distributed under a set of regularity conditions for tests involving dichotomous items and a unidimensional ability parameter (Klauer, 1990; Lord, 1983). This article first considers…

  20. Item Vector Plots for the Multidimensional Three-Parameter Logistic Model

    Science.gov (United States)

    Bryant, Damon; Davis, Larry

    2011-01-01

    This brief technical note describes how to construct item vector plots for dichotomously scored items fitting the multidimensional three-parameter logistic model (M3PLM). As multidimensional item response theory (MIRT) shows promise of being a very useful framework in the test development life cycle, graphical tools that facilitate understanding…

  1. Diagnosing Integrity of Transformer Windings by Applying Statistical Tools to Frequency Response Analysis Data Obtained at Site

    Directory of Open Access Journals (Sweden)

    M. Prameela

    2014-03-01

    Full Text Available This study presents the results of Sweep Frequency Response Analysis (SFRA measurement work carried out on number of power transformers at various sites involving problems like shorting of winding turns, core faults and related issues, On-Load Tap Changer (OLTC open contacts and winding displacement issues. The numerical parameters Viz., Min-Max ratio (MM, Mean Square Error (MSE, Maximum Absolute difference (MABS, Absolute Sum of Logarithmic Error (ASLE, Standard Deviation (S.D. and Correlation Coefficient (CC computed in three different frequency bands are presented to aid the interpretation of SFRA data. Comparison of frequency responses among different phases of the same transformer and with sister units were carried out to interpret the data. The study presents limits for various numerical parameters to diagnose the condition of the transformer and discriminate the faulty winding after accounting for manufacturing, design and asymmetry of the winding. The results presented in the study will help in interpreting the SFRA data by applying numerical techniques and assess the condition of the transformer.

  2. RESPONSE SURFACE METHODOLOGY APPLIED TO LACCASES ACTIVITIES EXHIBITED BY STENOTROPHOMONAS MALTOPHILIA AAP56 IN DIFFERENT GROWTH CONDITIONS

    Directory of Open Access Journals (Sweden)

    Said Galai,

    2011-12-01

    Full Text Available Stenotrophomonas maltophilia AAP56, laccase-producing bacteria, growing under different conditions, exhibit laccase activity that is highly affected by some environmental factors. Response surface methodology (RSM was applied for the determination of laccase factor dependence using two substrates: ABTS (2,2’-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid and DMP (2,6 Dimethoxy-phenol. RSM was carried out with a 24 factorial design using four variables, namely, dye (0 to 0.1 mg mL-1, Cu in Med (0 to 400 µM, shaking (0 to 150 rpm, and CuSO4 in assay (0 to 0.2 mM. Significant correlation between the effects of these variables on R1 (ABTS oxidase activity and R2 (DMP oxidase activity responses was detected. Astonishing results showed differences between these two activities with respect to copper activity dependence. Anoxic conditions exhibited a significant ability to induce the enzyme. This bacterial laccase activity (produced under optimal conditions according to RSM was used to decolorize an azoic dye, Reactive Black 5 (RB5. It was efficient only in the presence of a redox mediator to degrade RB5 after 20 min of incubation time.

  3. Het nut van item respons theorie bij de constructie en evaluatie van niet-cognitieve instrumenten voor selectie en assessment binnen organisaties. : (The usefulness of item response theory for the construction and evaluation of noncognitive tests in personnel selection and assessment.)

    NARCIS (Netherlands)

    Egberink, Iris J. L.; Meijer, Rob R.

    2012-01-01

    In this article we discuss the use of IRT for the development and application of noncognitive measures in personnel selection and career development. We introduce the basic principles of IRT and we discuss the usefulness of IRT to evaluate the quality of items and tests to assess the measurement pre

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

    OpenAIRE

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

    2009-01-01

    Introduction 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. Methods The process was stepwise: we sea...

  5. Estimating the Nominal Response Model Under Nonnormal Conditions

    OpenAIRE

    Preston, KSJ; Reise, SP

    2014-01-01

    The nominal response model (NRM), a much understudied polytomous item response theory (IRT) model, provides researchers the unique opportunity to evaluate within-item category distinctions. Polytomous IRT models, such as the NRM, are frequently applied to psychological assessments representing constructs that are unlikely to be normally distributed in the population. Unfortunately, models estimated using estimation software with the MML/EM algorithm frequently employs a set of normal quadratu...

  6. 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

  7. Increasing Active Student Responding in a University Applied Behavior Analysis Course: The Effect of Daily Assessment and Response Cards on End of Week Quiz Scores

    Science.gov (United States)

    Malanga, Paul R.; Sweeney, William J.

    2008-01-01

    The study compared the effects of daily assessment and response cards on average weekly quiz scores in an introduction to applied behavior analysis course. An alternating treatments design (Kazdin 1982, "Single-case research designs." New York: Oxford University Press; Cooper et al. 2007, "Applied behavior analysis." Upper Saddle River:…

  8. Three controversies over item disclosure in medical licensure examinations

    OpenAIRE

    Park, Yoon Soo; Yang, Eunbae B.

    2015-01-01

    In response to views on public’s right to know, there is growing attention to item disclosure – release of items, answer keys, and performance data to the public – in medical licensure examinations and their potential impact on the test’s ability to measure competence and select qualified candidates. Recent debates on this issue have sparked legislative action internationally, including South Korea, with prior discussions among North American countries dating over three decades. The purpose o...

  9. Towards microbiological quality assurance in radiation sterilization processing: the limiting case model applied to a microbial population having a distribution of radiation responses

    International Nuclear Information System (INIS)

    A limiting case model, developed earlier to provide a conservative estimate of the proportion of non-sterile items (P) in an irradiated population of items contaminated with micro-organisms of a single type, has been extended to include items having organisms of different types. Estimates of P are compared with exact values derived on purely theoretical grounds and with values obtained by computer simulation of microbiological inactivation on items. (author)

  10. Item Type and Gender Differences on the Mental Rotations Test

    Science.gov (United States)

    Voyer, Daniel; Doyle, Randi A.

    2010-01-01

    This study investigated gender differences on the Mental Rotations Test (MRT) as a function of item and response types. Accordingly, 86 male and 109 female undergraduate students completed the MRT without time limits. Responses were coded as reflecting two correct (CC), one correct and one wrong (CW), two wrong (WW), one correct and one blank…

  11. A method for accurate modelling of the crystal response function at a crystal sub-level applied to PET reconstruction

    Science.gov (United States)

    Stute, S.; Benoit, D.; Martineau, A.; Rehfeld, N. S.; Buvat, I.

    2011-02-01

    Positron emission tomography (PET) images suffer from low spatial resolution and signal-to-noise ratio. Accurate modelling of the effects affecting resolution within iterative reconstruction algorithms can improve the trade-off between spatial resolution and signal-to-noise ratio in PET images. In this work, we present an original approach for modelling the resolution loss introduced by physical interactions between and within the crystals of the tomograph and we investigate the impact of such modelling on the quality of the reconstructed images. The proposed model includes two components: modelling of the inter-crystal scattering and penetration (interC) and modelling of the intra-crystal count distribution (intraC). The parameters of the model were obtained using a Monte Carlo simulation of the Philips GEMINI GXL response. Modelling was applied to the raw line-of-response geometric histograms along the four dimensions and introduced in an iterative reconstruction algorithm. The impact of modelling interC, intraC or combined interC and intraC on spatial resolution, contrast recovery and noise was studied using simulated phantoms. The feasibility of modelling interC and intraC in two clinical 18F-NaF scans was also studied. Measurements on Monte Carlo simulated data showed that, without any crystal interaction modelling, the radial spatial resolution in air varied from 5.3 mm FWHM at the centre of the field-of-view (FOV) to 10 mm at 266 mm from the centre. Resolution was improved with interC modelling (from 4.4 mm in the centre to 9.6 mm at the edge), or with intraC modelling only (from 4.8 mm in the centre to 4.3 mm at the edge), and it became stationary across the FOV (4.2 mm FWHM) when combining interC and intraC modelling. This improvement in resolution yielded significant contrast enhancement, e.g. from 65 to 76% and 55.5 to 68% for a 6.35 mm radius sphere with a 3.5 sphere-to-background activity ratio at 55 and 215 mm from the centre of the FOV, respectively

  12. A method for accurate modelling of the crystal response function at a crystal sub-level applied to PET reconstruction

    International Nuclear Information System (INIS)

    Positron emission tomography (PET) images suffer from low spatial resolution and signal-to-noise ratio. Accurate modelling of the effects affecting resolution within iterative reconstruction algorithms can improve the trade-off between spatial resolution and signal-to-noise ratio in PET images. In this work, we present an original approach for modelling the resolution loss introduced by physical interactions between and within the crystals of the tomograph and we investigate the impact of such modelling on the quality of the reconstructed images. The proposed model includes two components: modelling of the inter-crystal scattering and penetration (interC) and modelling of the intra-crystal count distribution (intraC). The parameters of the model were obtained using a Monte Carlo simulation of the Philips GEMINI GXL response. Modelling was applied to the raw line-of-response geometric histograms along the four dimensions and introduced in an iterative reconstruction algorithm. The impact of modelling interC, intraC or combined interC and intraC on spatial resolution, contrast recovery and noise was studied using simulated phantoms. The feasibility of modelling interC and intraC in two clinical 18F-NaF scans was also studied. Measurements on Monte Carlo simulated data showed that, without any crystal interaction modelling, the radial spatial resolution in air varied from 5.3 mm FWHM at the centre of the field-of-view (FOV) to 10 mm at 266 mm from the centre. Resolution was improved with interC modelling (from 4.4 mm in the centre to 9.6 mm at the edge), or with intraC modelling only (from 4.8 mm in the centre to 4.3 mm at the edge), and it became stationary across the FOV (4.2 mm FWHM) when combining interC and intraC modelling. This improvement in resolution yielded significant contrast enhancement, e.g. from 65 to 76% and 55.5 to 68% for a 6.35 mm radius sphere with a 3.5 sphere-to-background activity ratio at 55 and 215 mm from the centre of the FOV, respectively

  13. MMPI-2 Item Endorsements in Dissociative Identity Disorder vs. Simulators.

    Science.gov (United States)

    Brand, Bethany L; Chasson, Gregory S; Palermo, Cori A; Donato, Frank M; Rhodes, Kyle P; Voorhees, Emily F

    2016-03-01

    Elevated scores on some MMPI-2 (Minnesota Multiphasic Inventory-2) validity scales are common among patients with dissociative identity disorder (DID), which raises questions about the validity of their responses. Such patients show elevated scores on atypical answers (F), F-psychopathology (Fp), atypical answers in the second half of the test (FB), schizophrenia (Sc), and depression (D) scales, with Fp showing the greatest utility in distinguishing them from coached and uncoached DID simulators. In the current study, we investigated the items on the MMPI-2 F, Fp, FB, Sc, and D scales that were most and least commonly endorsed by participants with DID in our 2014 study and compared these responses with those of coached and uncoached DID simulators. The comparisons revealed that patients with DID most frequently endorsed items related to dissociation, trauma, depression, fearfulness, conflict within family, and self-destructiveness. The coached group more successfully imitated item endorsements of the DID group than did the uncoached group. However, both simulating groups, especially the uncoached group, frequently endorsed items that were uncommonly endorsed by the DID group. The uncoached group endorsed items consistent with popular media portrayals of people with DID being violent, delusional, and unlawful. These results suggest that item endorsement patterns can provide useful information to clinicians making determinations about whether an individual is presenting with DID or feigning. PMID:26944745

  14. Approximate Revenue Maximization with Multiple Items

    OpenAIRE

    Sergiu Hart; Noam Nisan

    2012-01-01

    Myerson's classic result provides a full description of how a seller can maximize revenue when selling a single item. We address the question of revenue maximization in the simplest possible multi-item setting: two items and a single buyer who has independently distributed values for the items, and an additive valuation. In general, the revenue achievable from selling two independent items may be strictly higher than the sum of the revenues obtainable by selling each of them separately. In fa...

  15. 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

  16. 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

  17. Prediction of true test scores from observed item scores and ancillary data.

    Science.gov (United States)

    Haberman, Shelby J; Yao, Lili; Sinharay, Sandip

    2015-05-01

    In many educational tests which involve constructed responses, a traditional test score is obtained by adding together item scores obtained through holistic scoring by trained human raters. For example, this practice was used until 2008 in the case of GRE(®) General Analytical Writing and until 2009 in the case of TOEFL(®) iBT Writing. With use of natural language processing, it is possible to obtain additional information concerning item responses from computer programs such as e-rater(®). In addition, available information relevant to examinee performance may include scores on related tests. We suggest application of standard results from classical test theory to the available data to obtain best linear predictors of true traditional test scores. In performing such analysis, we require estimation of variances and covariances of measurement errors, a task which can be quite difficult in the case of tests with limited numbers of items and with multiple measurements per item. As a consequence, a new estimation method is suggested based on samples of examinees who have taken an assessment more than once. Such samples are typically not random samples of the general population of examinees, so that we apply statistical adjustment methods to obtain the needed estimated variances and covariances of measurement errors. To examine practical implications of the suggested methods of analysis, applications are made to GRE General Analytical Writing and TOEFL iBT Writing. Results obtained indicate that substantial improvements are possible both in terms of reliability of scoring and in terms of assessment reliability. PMID:25773314

  18. Selection of Common Items as an Unrecognized Source of Variability in Test Equating: A Bootstrap Approximation Assuming Random Sampling of Common Items

    Science.gov (United States)

    Michaelides, Michalis P.; Haertel, Edward H.

    2014-01-01

    The standard error of equating quantifies the variability in the estimation of an equating function. Because common items for deriving equated scores are treated as fixed, the only source of variability typically considered arises from the estimation of common-item parameters from responses of samples of examinees. Use of alternative, equally…

  19. Decoding dynamic brain patterns from evoked responses: A tutorial on multivariate pattern analysis applied to time-series neuroimaging data

    OpenAIRE

    Grootswagers, Tijl; Wardle, Susan G.; Carlson, Thomas A.

    2016-01-01

    Multivariate pattern analysis (MVPA) or brain decoding methods have become standard practice in analysing fMRI data. Although decoding methods have been extensively applied in Brain Computing Interfaces (BCI), these methods have only recently been applied to time-series neuroimaging data such as MEG and EEG to address experimental questions in Cognitive Neuroscience. In a tutorial-style review, we describe a broad set of options to inform future time-series decoding studies from a Cognitive N...

  20. Monte Carlo simulation of the response functions of Cd Te detectors to be applied in X-rays spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Tomal, A. [Universidade Federale de Goias, Instituto de Fisica, Campus Samambaia, 74001-970, Goiania, (Brazil); Lopez G, A. H.; Santos, J. C.; Costa, P. R., E-mail: alessandra_tomal@yahoo.com.br [Universidade de Sao Paulo, Instituto de Fisica, Rua du Matao Travessa R. 187, Cidade Universitaria, 05508-090 Sao Paulo (Brazil)

    2014-08-15

    In this work, the energy response functions of a Cd Te detector were obtained by Monte Carlo simulation in the energy range from 5 to 150 keV, using the Penelope code. The response functions simulated included the finite detector resolution and the carrier transport. The simulated energy response matrix was validated through comparison with experimental results obtained for radioactive sources. In order to investigate the influence of the correction by the detector response at diagnostic energy range, x-ray spectra were measured using a Cd Te detector (model Xr-100-T, Amptek), and then corrected by the energy response of the detector using the stripping procedure. Results showed that the Cd Te exhibit good energy response at low energies (below 40 keV), showing only small distortions on the measured spectra. For energies below about 70 keV, the contribution of the escape of Cd- and Te-K x-rays produce significant distortions on the measured x-ray spectra. For higher energies, the most important correction is the detector efficiency and the carrier trapping effects. The results showed that, after correction by the energy response, the measured spectra are in good agreement with those provided by different models from the literature. Finally, our results showed that the detailed knowledge of the response function and a proper correction procedure are fundamental for achieve more accurate spectra from which several qualities parameters (i.e. half-value layer, effective energy and mean energy) can be determined. (Author)

  1. Guidelines based on validity criteria for the development of multiple choice items

    OpenAIRE

    Moreno Rodríguez, Rafael; Martínez Cervantes, Rafael Jesús; Muñiz Fernández, José

    2015-01-01

    Background: Many different guidelines have been presented for the construction of multiple choice items. Those guidelines have been based on the observation of errors when constructing items but not on any clear scientifi c criterion. Our main objective was to draw up guidelines for the development of multiple choice items based on validity criteria. Method: We used the properties of adjustment, precision, and differentiation, applying them to three basic phases of instrumen...

  2. Development of the Assessment Items of Debris Flow Using the Delphi Method

    Science.gov (United States)

    Byun, Yosep; Seong, Joohyun; Kim, Mingi; Park, Kyunghan; Yoon, Hyungkoo

    2016-04-01

    In recent years in Korea, Typhoon and the localized extreme rainfall caused by the abnormal climate has increased. Accordingly, debris flow is becoming one of the most dangerous natural disaster. This study aimed to develop the assessment items which can be used for conducting damage investigation of debris flow. Delphi method was applied to classify the realms of assessment items. As a result, 29 assessment items which can be classified into 6 groups were determined.

  3. Editors' Conclusion: Child, Youth, and Parent Responses to the Terrorism of September 11, 2001--Implications for Applied Developmental Science and Practice

    Science.gov (United States)

    Aber, J. Lawrence; Gershoff, Elizabeth T.

    2004-01-01

    Even as the events of September 11, 2001 recede into the past, the need for applied developmental science to lend its expertise to assist with one's understanding of and coping with civilian responses to terrorism has never been greater. What has the field learned from studies of the effects of events of September 11th on children, youths, and…

  4. The Relationship between Item Context Characteristics and Student Performance: The Case of the 2006 and 2009 PISA Science Items

    Science.gov (United States)

    Ruiz-Primo, Maria Araceli; Li, Min

    2015-01-01

    Background: A long-standing premise in test design is that contextualizing test items makes them concrete, less demanding, and more conducive to determining whether students can apply or transfer their knowledge. Purpose: We assert that despite decades of study and experience, much remains to be learned about how to construct effective and fair…

  5. Item Overlap Correlations: Definitions, Interpretations, and Implications.

    Science.gov (United States)

    Hsu, Louis M.

    1994-01-01

    Item overlap coefficient (IOC) formulas are discussed, providing six warnings about their calculation and interpretation and some explanations of why item overlap influences the Minnesota Multiphasic Personality Inventory and the Millon Clinical Multiaxial Inventory factor structures. (SLD)

  6. Investigating factors affecting students’ performance to PISA Science items

    Directory of Open Access Journals (Sweden)

    V. Hatzinikita

    2008-01-01

    Full Text Available The present paper aims to investigate, on the one hand, the extent to which PISA Science items validly assess the knowledge and skills of 15 year-old Greek students, while, on the other hand, to examine the effect of the following factors: student’s gender, scientific processes and contexts (situations on the students’ performance in these PISA items. The research used paper-and-pencil test with published PISA Science items, conducted individual semi-structured interviews with 15 year-old students and finally marked the students’ responses, according to the PISA marking guide. Τhe basic finding resulting from the data analysis is that the paper-and-pencil test with the PISA Science items does not tend, unlike the interview, to effectively record the Greek students’ Science knowledge and skills. Moreover, the analysis revealed that the performance of students in the PISA Science items (paper-and-pencil test and interview tend to be independent of the student’s gender and depend on the context in which the knowledge and processes are assessed. Additionally, the possible correlation between the students’ performance and the factor of scientific processes seems to depend on the setting in which the students provide their responses (paper-and-pencil test or interview.

  7. Monte Carlo simulation of the response functions of CdTe detectors to be applied in x-ray spectroscopy.

    Science.gov (United States)

    Tomal, A; Santos, J C; Costa, P R; Lopez Gonzales, A H; Poletti, M E

    2015-06-01

    In this work, the energy response functions of a CdTe detector were obtained by Monte Carlo (MC) simulation in the energy range from 5 to 160keV, using the PENELOPE code. In the response calculations the carrier transport features and the detector resolution were included. The computed energy response function was validated through comparison with experimental results obtained with (241)Am and (152)Eu sources. In order to investigate the influence of the correction by the detector response at diagnostic energy range, x-ray spectra were measured using a CdTe detector (model XR-100T, Amptek), and then corrected by the energy response of the detector using the stripping procedure. Results showed that the CdTe exhibits good energy response at low energies (below 40keV), showing only small distortions on the measured spectra. For energies below about 80keV, the contribution of the escape of Cd- and Te-K x-rays produce significant distortions on the measured x-ray spectra. For higher energies, the most important correction is the detector efficiency and the carrier trapping effects. The results showed that, after correction by the energy response, the measured spectra are in good agreement with those provided by a theoretical model of the literature. Finally, our results showed that the detailed knowledge of the response function and a proper correction procedure are fundamental for achieving more accurate spectra from which quality parameters (i.e., half-value layer and homogeneity coefficient) can be determined. PMID:25599872

  8. 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)

  9. The PROMIS Physical Function item bank was calibrated to a standardized metric and shown to improve measurement efficiency

    DEFF Research Database (Denmark)

    Rose, Matthias; Bjørner, Jakob; Gandek, Barbara;

    2014-01-01

    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. RESULTS: 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...

  10. 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)

  11. Real and Artificial Differential Item Functioning

    Science.gov (United States)

    Andrich, David; Hagquist, Curt

    2012-01-01

    The literature in modern test theory on procedures for identifying items with differential item functioning (DIF) among two groups of persons includes the Mantel-Haenszel (MH) procedure. Generally, it is not recognized explicitly that if there is real DIF in some items which favor one group, then as an artifact of this procedure, artificial DIF…

  12. Design patterns for digital item types in higher education

    NARCIS (Netherlands)

    Draaijer, S.; Hartog, R.J.M.

    2007-01-01

    A set of design patterns for digital item types has been developed in response to challenges identified in various projects by teachers in higher education. The goal of the projects in question was to design and develop formative and summative tests, and to develop interactive learning material in t

  13. IRT-Estimated Reliability for Tests Containing Mixed Item Formats

    Science.gov (United States)

    Shu, Lianghua; Schwarz, Richard D.

    2014-01-01

    As a global measure of precision, item response theory (IRT) estimated reliability is derived for four coefficients (Cronbach's a, Feldt-Raju, stratified a, and marginal reliability). Models with different underlying assumptions concerning test-part similarity are discussed. A detailed computational example is presented for the targeted…

  14. 32 CFR 507.17 - Procurement and wear of heraldic items.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 3 2010-07-01 2010-07-01 true Procurement and wear of heraldic items. 507.17... AUTHORITIES AND PUBLIC RELATIONS MANUFACTURE AND SALE OF DECORATIONS, MEDALS, BADGES, INSIGNIA, COMMERCIAL USE... Procurement and wear of heraldic items. (a) The provisions of this part do not apply to contracts awarded...

  15. Applications of NLP Techniques to Computer-Assisted Authoring of Test Items for Elementary Chinese

    Science.gov (United States)

    Liu, Chao-Lin; Lin, Jen-Hsiang; Wang, Yu-Chun

    2010-01-01

    The authors report an implemented environment for computer-assisted authoring of test items and provide a brief discussion about the applications of NLP techniques for computer assisted language learning. Test items can serve as a tool for language learners to examine their competence in the target language. The authors apply techniques for…

  16. A comparison of response spectrum and direct integration analysis methods as applied to a nuclear component support structure (U)

    International Nuclear Information System (INIS)

    Seismic qualification of Class I nuclear components is accomplished using a variety of analytical methods. This paper compares the results of time history dynamic analyses of a heat exchanger support structure using response spectrum and time history direct integration analysis methods. Dynamic analysis is performed on the detailed component models using the two methods. A linear elastic model is used for both the response spectrum and direct integration methods. A nonlinear model, which includes friction and nonlinear springs, is analyzed using time history input by direct integration. The loads from the three cases are compared

  17. 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…

  18. Expected Equating Error Resulting from Incorrect Handling of Item Parameter Drift among the Common Items

    Science.gov (United States)

    Miller, G. Edward; Fitzpatrick, Steven J.

    2009-01-01

    Incorrect handling of item parameter drift during the equating process can result in equating error. If the item parameter drift is due to construct-irrelevant factors, then inclusion of these items in the estimation of the equating constants can be expected to result in equating error. On the other hand, if the item parameter drift is related to…

  19. Social Responsibility in Research Practice: Engaging applied scientists with the socio-ethical context of their work

    NARCIS (Netherlands)

    Schuurbiers, D.

    2010-01-01

    How to encourage researchers to critically reflect on the ethical and social dimensions of their work? That is the central research question of this thesis. It starts from the assumption that the neutrality view of the social responsibility of the researcher – the view that researchers have no busin

  20. Schema-Triggered Cognitive and Affective Response to Music: Applying an Information-Processing Model to Rock 'N' Roll.

    Science.gov (United States)

    Voelker, David H.; Pettey, Gary R.

    To account for cognitive and affective responses to popular music, a pilot study used an information processing model to show that affect results largely from the activation of affect-laden schemas by the music stimulus. Subjects, 196 students from an introductory course in interpersonal communication at a medium-sized university, listened to a…

  1. 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.

  2. Differential item functioning in Patient Reported Outcomes Measurement Information System® (PROMIS®) Physical Functioning short forms: Analyses across ethnically diverse groups

    OpenAIRE

    Jones, Richard N.; Doug Tommet; Mildred Ramirez; Roxanne Jensen; Teresi, Jeanne A.

    2016-01-01

    We analyzed physical functioning short form items derived from the PROMIS® item bank (PF16) using data from more than 5,000 recently diagnosed, ethnically diverse cancer patients. Our goal was to determine if the short form items demonstrated evidence of differential item functioning (DIF) according to sociodemographic characteristics in this clinical sample. We evaluated respons-es for evidence of unidimensionality, local independence (given a single common factor), differen-tial item functi...

  3. Understanding emotional responses to breast/ovarian cancer genetic risk assessment: an applied test of a cognitive theory of emotion.

    Science.gov (United States)

    Phelps, Ceri; Bennett, Paul; Brain, Kate

    2008-10-01

    This study explored whether Smith and Lazarus' (1990, 1993) cognitive theory of emotion could predict emotional responses to an emotionally ambiguous real-life situation. Questionnaire data were collected from 145 women upon referral for cancer genetic risk assessment. These indicated a mixed emotional reaction of both positive and negative emotions to the assessment. Hierarchical regression analyses revealed that the hypothesised models explained between 20% and 33% of the variance of anxiety, hope and gratitude scores, but only 10% of the variance for challenge scores. For the previously unmodelled emotion of relief, 31% of the variance was explained by appraisals and core relational themes. The findings help explain why emotional responses to cancer genetic risk assessment vary and suggest that improving the accuracy of individuals' beliefs and expectations about the assessment process may help subsequent adaptation to risk information. PMID:18942008

  4. GIS analysis to apply theoretical Minimal Model on glacier flow line and assess glacier response in climate change scenarios

    OpenAIRE

    M. Moretti; Mattavelli, M; De Amicis, Mattia; Maggi, V

    2014-01-01

    The development of theoretical work about glacier dynamics has given rise to the construction of mathematical models to assess glacier response in climate change scenarios. Glacier are sentinels of climate condition and the Project of Interest NextData will favour new data production about the present and past climatic variability and future climate projections, as well as new assessments of the impact of climate change on environment. The aim of this specific research program is to develo...

  5. Diagnosing Integrity of Transformer Windings by Applying Statistical Tools to Frequency Response Analysis Data Obtained at Site

    OpenAIRE

    M. Prameela; Pradeep M. Nirgude; G. Radhakrishna Murthy

    2014-01-01

    This study presents the results of Sweep Frequency Response Analysis (SFRA) measurement work carried out on number of power transformers at various sites involving problems like shorting of winding turns, core faults and related issues, On-Load Tap Changer (OLTC) open contacts and winding displacement issues. The numerical parameters Viz., Min-Max ratio (MM), Mean Square Error (MSE), Maximum Absolute difference (MABS), Absolute Sum of Logarithmic Error (ASLE), Standard Deviation (S.D.) and Co...

  6. A hybrid multiple criteria decision analysis framework for corporate social responsibility implementation applied to an extractive industry case study

    OpenAIRE

    Poplawska, Jolanta; Labib, Ashraf; Reed, Debbie

    2015-01-01

    Integration of Corporate Social Responsibility (CSR) into a company’s mainstream strategy is a complex task. Practical implementation of CSR requires analysis of both the external and internal environments to determine the prospects and challenges significantly influencing integration of sustainability into business strategy. In order to overcome limitations of single multi criteria decision analysis (MCDA) models, this article proposes a hybrid integrated framework combining cognitive mappin...

  7. Parallel Matrix Factorization for Binary Response

    CERN Document Server

    Khanna, Rajiv; Agarwal, Deepak; Chen, Beechung

    2012-01-01

    Predicting user affinity to items is an important problem in applications like content optimization, computational advertising, and many more. While bilinear random effect models (matrix factorization) provide state-of-the-art performance when minimizing RMSE through a Gaussian response model on explicit ratings data, applying it to imbalanced binary response data presents additional challenges that we carefully study in this paper. Data in many applications usually consist of users' implicit response that are often binary -- clicking an item or not; the goal is to predict click rates, which is often combined with other measures to calculate utilities to rank items at runtime of the recommender systems. Because of the implicit nature, such data are usually much larger than explicit rating data and often have an imbalanced distribution with a small fraction of click events, making accurate click rate prediction difficult. In this paper, we address two problems. First, we show previous techniques to estimate bi...

  8. 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…

  9. A Paradox in the Study of the Benefits of Test-Item Review

    Science.gov (United States)

    van der Linden, Wim J.; Jeon, Minjeong; Ferrara, Steve

    2011-01-01

    According to a popular belief, test takers should trust their initial instinct and retain their initial responses when they have the opportunity to review test items. More than 80 years of empirical research on item review, however, has contradicted this belief and shown minor but consistently positive score gains for test takers who changed…

  10. 75 FR 57287 - Notice of Intent to Repatriate a Cultural Item: Oshkosh Public Museum, Oshkosh, WI

    Science.gov (United States)

    2010-09-20

    ... National Park Service Notice of Intent to Repatriate a Cultural Item: Oshkosh Public Museum, Oshkosh, WI... repatriate a cultural item in the possession of the Oshkosh Public Museum, Oshkosh, WI, that meets the... determinations in this notice are the sole responsibility of the museum, institution, or Federal agency that...

  11. 76 FR 28065 - Notice of Intent To Repatriate a Cultural Item: Montana Historical Society, Helena, MT

    Science.gov (United States)

    2011-05-13

    ... National Park Service Notice of Intent To Repatriate a Cultural Item: Montana Historical Society, Helena... repatriate a cultural item in the possession of the Montana Historical Society, Helena, MT, that meets the... notice are the sole responsibility of the museum, institution, or Federal agency that has control of...

  12. 49 CFR 375.207 - What items must be in my advertisements?

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 5 2010-10-01 2010-10-01 false What items must be in my advertisements? 375.207... Services to My Customers General Responsibilities § 375.207 What items must be in my advertisements? (a) You and your agents must publish and use only truthful, straightforward, and honest advertisements....

  13. A Simulation Study of the Effects of Ability Range Restriction on IRT Item Bias Detection Procedures.

    Science.gov (United States)

    Lautenschlager, Gary J.; Park, Dong-Gun

    The effects of variations in degree of range restriction and different subgroup sample sizes on the validity of several item bias detection procedures based on Item Response Theory (IRT) were investigated in a simulation study. The degree of range restriction for each of two subpopulations was varied by cutting the specified subpopulation ability…

  14. IRT Item Parameter Recovery with Marginal Maximum Likelihood Estimation Using Loglinear Smoothing Models

    Science.gov (United States)

    Casabianca, Jodi M.; Lewis, Charles

    2015-01-01

    Loglinear smoothing (LLS) estimates the latent trait distribution while making fewer assumptions about its form and maintaining parsimony, thus leading to more precise item response theory (IRT) item parameter estimates than standard marginal maximum likelihood (MML). This article provides the expectation-maximization algorithm for MML estimation…

  15. Applying Central Composite Design and Response Surface Methodology to Optimize Growth and Biomass Production of Haemophilus influenzae Type b

    Science.gov (United States)

    Momen, Seyed Bahman; Siadat, Seyed Davar; Akbari, Neda; Ranjbar, Bijan; Khajeh, Khosro

    2016-01-01

    Background Haemophilus influenzae type b (Hib) is the leading cause of bacterial meningitis, otitis media, pneumonia, cellulitis, bacteremia, and septic arthritis in infants and young children. The Hib capsule contains the major virulence factor, and is composed of polyribosyl ribitol phosphate (PRP) that can induce immune system response. Vaccines consisting of Hib capsular polysaccharide (PRP) conjugated to a carrier protein are effective in the prevention of the infections. However, due to costly processes in PRP production, these vaccines are too expensive. Objectives To enhance biomass, in this research we focused on optimizing Hib growth with respect to physical factors such as pH, temperature, and agitation by using a response surface methodology (RSM). Materials and Methods We employed a central composite design (CCD) and a response surface methodology to determine the optimum cultivation conditions for growth and biomass production of H. influenzae type b. The treatment factors investigated were initial pH, agitation, and temperature, using shaking flasks. After Hib cultivation and determination of dry biomass, analysis of experimental data was performed by the RSM-CCD. Results The model showed that temperature and pH had an interactive effect on Hib biomass production. The dry biomass produced in shaking flasks was about 5470 mg/L, which was under an initial pH of 8.5, at 250 rpm and 35° C. Conclusions We found CCD and RSM very effective in optimizing Hib culture conditions, and Hib biomass production was greatly influenced by pH and incubation temperature. Therefore, optimization of the growth factors to maximize Hib production can lead to 1) an increase in bacterial biomass and PRP productions, 2) lower vaccine prices, 3) vaccination of more susceptible populations, and 4) lower risk of Hib infections.

  16. Response surface method applied to the thermoeconomic optimization of a complex cogeneration system modeled in a process simulator

    International Nuclear Information System (INIS)

    This work presents the application of a surrogate model – a response surface – to replace the objective function to be minimized in the thermoeconomic optimization of a complex thermal system modeled with the aid of an expert process simulator. The objective function accounts for fuel, capital, operation and maintenance costs of the thermal system, and depends on nine decision variables. The minimization task is performed through the computational integration of two professional programs, a process simulator and a mathematical platform. Five algorithms are used to perform the optimization: the pattern search and genetic algorithms, both available in the mathematical platform, plus three custom-coded algorithms, differential evolution, particle swarm and simulated annealing. A comparative analysis of the performance of all five methods is presented, together with a critical appraisal of the surrogate model effectiveness. In the course of the optimization procedure, the process simulator computes the thermodynamic properties of all flows of the thermal system and solves the mass and energy balances each time the objective function has to be evaluated. By handling a set of radial basis functions as an approximation model to the original computationally expensive objective function, it is found here that the number of function evaluations can be appreciably reduced without significant deviation of the optimal value. The present study indicates that, for a thermoeconomic system optimization problem with a large number of decision variables and/or a costly objective function, the application of the response surface surrogate may prove more efficient than the original simulation model, reducing substantially the computational time involved in the optimization. - Highlights: ► A successful response surface method was proposed. ► The surrogate model may be more efficient than the original simulation model. ► Relative differences of less than 5% were found for the

  17. Segmenting and targeting American university students to promote responsible alcohol use: a case for applying social marketing principles.

    Science.gov (United States)

    Deshpande, Sameer; Rundle-Thiele, Sharyn

    2011-10-01

    The current study contributes to the social marketing literature in the American university binge-drinking context in three innovative ways. First, it profiles drinking segments by "values" and "expectancies" sought from behaviors. Second, the study compares segment values and expectancies of two competing behaviors, that is, binge drinking and participation in alternative activities. Third, the study compares the influence of a variety of factors on both behaviors in each segment. Finally, based on these findings and feedback from eight university alcohol prevention experts, appropriate strategies to promote responsible alcohol use for each segment are proposed. PMID:22054026

  18. Current Situations and Future Perspectives of Applying Corporate Responsibility in Finland : Cases: Alma Media, Finnair, Finnvera, Metso, UPM

    OpenAIRE

    Bui, Nghiem Dac Vinh

    2012-01-01

    Corporate Responsibility (CR) has been a very popular concept these days in business life. Stakeholders use CR to monitor and evaluate a company's operation(s). Companies use CR as a method of risk management, strategic marketing, and even in attracting new investors. The emerging of CR worldwide is really fast and obvious. Within 50 years, CR has developed from a small initiative to be an important part of every business. In Finland, the concept of CR was also adopted and utilised. This pape...

  19. Periradicular Tissue Responses to Biologically Active Molecules or MTA When Applied in Furcal Perforation of Dogs' Teeth

    Directory of Open Access Journals (Sweden)

    Anna Zairi

    2012-01-01

    Full Text Available The aim of this study was the comparative evaluation of inflammatory reactions and tissue responses to four growth factors, or mineral trioxide aggregate (MTA, or a zinc-oxide-eugenol-based cement (IRM as controls, when used for the repair of furcal perforations in dogs’ teeth. Results showed significantly higher inflammatory cell response in the transforming growth factorβ1 (TGFβ1 and zinc-oxide-eugenol-based cement (IRM groups and higher rates of epithelial proliferation in the TGFβ1, basic fibroblast growth factor (bFGF, and insulin growth factor-I (IGF-I groups compared to the MTA. Significantly higher rates of bone formation were found in the control groups compared to the osteogenic protein-1 (OP-1. Significantly higher rates of cementum formation were observed in the IGF-I and bFGF groups compared to the IRM. None of the biologically active molecules can be suggested for repairing furcal perforations, despite the fact that growth factors exerted a clear stimulatory effect on cementum formation and inhibited collagen capsule formation. MTA exhibited better results than the growth factors.

  20. Assessment of Water Quality in Coastal Environments of Mohammedia Applying Responses of Biochemical Biomarkers in the Brown Mussel Perna perna

    Directory of Open Access Journals (Sweden)

    Laila El Jourmi

    2012-01-01

    Full Text Available The present work aims to assess the marine environment quality in Mohammedia, using the response of the biochemical biomarkers in the brown mussel Perna perna. The biomarkers selected in this work are : glutathione S-transferase (GST as phase II enzyme and the acetylcholinesterase (AChE activity as neurotoxicity marker. The Oxidative stress is evaluated using catalase (CAT, a well-known anti-oxidant enzyme, and malondialdehyde (MDA accumulation as marker of oxidation of membrane phospholipids through lipid peroxidation. And finally the metallothioneine (MT as stress proteins. Our data indicated that CAT, GST activity and MDA, MT concentration in whole mussel bodies, are a higher and significant (p 0.05 in mussels collected at polluted site when compared to specimen sampled from control one.In contrary the response of AChE activity was significantly inhibited in mussels from polluted site when compared to control value. The multi-marker results confirm that mussels from Mohammedia have been submitted to polluted environment.

  1. Applying the universal neutron transport codes to the calculation of well-logging probe response at different rock porosities

    International Nuclear Information System (INIS)

    The use of universal neutron transport codes in order to calculate the parameters of well-logging probes presents a new approach first tried in U.S.A. and UK in the eighties. This paper deals with first such an attempt in Poland. The work is based on the use of MORSE code developed in Oak Ridge National Laboratory in U.S.A.. Using CG MORSE code we calculated neutron detector response when surrounded with sandstone of porosities 19% and 38%. During the work it come out that it was necessary to investigate different methods of estimation of the neutron flux. The stochastic estimation method as used currently in the original MORSE code (next collision approximation) can not be used because of slow convergence of its variance. Using the analog type of estimation (calculation of the sum of track lengths inside detector) we obtained results of acceptable variance (∼ 20%) for source-detector spacing smaller than 40 cm. The influence of porosity on detector response is correctly described for detector positioned at 27 cm from the source. At the moment the variances are quite large. (author). 33 refs, 8 figs, 8 tabs

  2. Wavelet prism decomposition analysis applied to CARS spectroscopy: a tool for accurate and quantitative extraction of resonant vibrational responses.

    Science.gov (United States)

    Kan, Yelena; Lensu, Lasse; Hehl, Gregor; Volkmer, Andreas; Vartiainen, Erik M

    2016-05-30

    We propose an approach, based on wavelet prism decomposition analysis, for correcting experimental artefacts in a coherent anti-Stokes Raman scattering (CARS) spectrum. This method allows estimating and eliminating a slowly varying modulation error function in the measured normalized CARS spectrum and yields a corrected CARS line-shape. The main advantage of the approach is that the spectral phase and amplitude corrections are avoided in the retrieved Raman line-shape spectrum, thus significantly simplifying the quantitative reconstruction of the sample's Raman response from a normalized CARS spectrum in the presence of experimental artefacts. Moreover, the approach obviates the need for assumptions about the modulation error distribution and the chemical composition of the specimens under study. The method is quantitatively validated on normalized CARS spectra recorded for equimolar aqueous solutions of D-fructose, D-glucose, and their disaccharide combination sucrose. PMID:27410113

  3. Measuring prescribing: the shortcomings of the item.

    OpenAIRE

    Bogle, S. M.; Harris, C. M.

    1994-01-01

    OBJECTIVES--To assess the validity of the item as a measure of the volume of a drug prescribed; and to investigate the possibility that higher quantities per item are prescribed for patients who are not exempt from the prescription charge. DESIGN--Five substudies. For the first, a frequency distribution was derived of the different quantities per item of 10 commonly used drugs prescribed by 20 randomly selected practices in each of five family health service authority areas. For the second, t...

  4. Postural responses applied in a control model in cochlear implant users with pre-lingual hearing loss.

    Science.gov (United States)

    Suarez, Hamlet; Ferreira, Enrique; Alonso, Rafael; Arocena, Sofia; San Roman, Cecilia; Herrera, Tamara; Lapilover, Valeria

    2016-04-01

    Conclusions The assessment of postural responses (PR) based in a feedback control system model shows selective gains in different bands of frequencies adaptable with child development. Objective PR characterization of pre-lingual cochlear implant users (CIU) in different sensory conditions. Methods Total energy consumption of the body's center of pressure signal (ECCOP) and its distribution in three bands of frequencies: band 1 (0-0.1 Hz), band 2 (0.1-0.7 Hz), and band 3 (0.7-20 Hz) was measured in a sample of 18 CIU (8-16 years old) and in a control group (CG) (8-15 years old). They were assessed in a standing position on a force platform in two sensory conditions: 1 = Eyes open. 2 = Eyes closed and standing on foam. Results In condition 1, total ECCOP of PR and its proportion of energy consumption in the three bands of frequencies were similar between CIU and CG (p > 0.05). In condition 2, CIU have significantly higher ECCOP, mainly in high frequencies (bands 2 and 3) (p < 0.05). ECCOP values decreased with age also, mainly in bands 2 and 3. This behavior is interpreted in the control system model proposed as an adaptation process related with child development. PMID:26824633

  5. Nursing students' response to self-directed learning: an evaluation of a learning process applying Jarvis' framework.

    Science.gov (United States)

    Pedley, G E; Arber, A

    1997-02-01

    This paper evaluates the effectiveness of a student-centred module of learning using Jarvis' experiential framework. One hundred and thirty-five students undertook the module over a 9-month period. A semi-structured questionnaire was used to explore students' learning, choice of topic, structure, and benefit of the module. The data were analysed using simple descriptive statistics and content analysis. A key theme emerged related to the beneficial learning experience. Presentation skills/shared learning, choice and autonomy, taking responsibility, and research skills were other themes that emerged. Whilst the literature suggests students dislike experiential forms of learning, the positive evaluation of this module demonstrates that it can be used effectively. Furthermore, Jarvis' model provides a useful framework for structuring this approach to learning. One of the research strategies within a nursing faculty should be to develop progressive student-focused educational methods and evaluate their effect or professional preparation. This, it is argued, needs to be perceived as a valuable and essential activity within an academic nursing department. PMID:9044017

  6. Does radioadaptive response also apply to the case of heavy-ion irradiations in fetal and adult mice?

    International Nuclear Information System (INIS)

    Possible induction of adaptive response (AR) by the high linear energy transfer (LET) accelerated heavy ion irradiations (HI) is being attempted both in young adult female mice and in fetal mice of C57BL/6J Jms strain, using growth delay, hematopoietic damage and reduced survival in vivo, prenatal growth delay, malformation and death in utero as endpoints. In this fiscal year, using carbon, silicon, neon, and iron ion irradiations and X-rays, we demonstrated that 1) in the in utero studies, the priming low dose X-irradiations could induce protective effects against the detrimental effects from the high LET heavy-ion challenging irradiations from neon but not from iron beams; 2) in the in vivo studies, the priming low dose X-irradiations could induce protective effects against the detrimental effects from the high LET heavy-ion challenging irradiations from neon beams; 3) also in the in vivo studies, priming low dose of high LET iron ions did not show any protective effects against challenging dose from X-rays while priming low dose of high LET carbon ions could induce protective effects against the detrimental effects from the high LET heavy-ion challenging irradiations from neon beams. (author)

  7. 41 CFR 101-30.701-1 - Item reduction study.

    Science.gov (United States)

    2010-07-01

    ... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true Item reduction study. 101....7-Item Reduction Program § 101-30.701-1 Item reduction study. Item reduction study means the study... so identified, a replacement item shall be proposed. The result of item reduction studies...

  8. 41 CFR 101-30.701-2 - Item standardization code.

    Science.gov (United States)

    2010-07-01

    ... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true Item standardization code....7-Item Reduction Program § 101-30.701-2 Item standardization code. Item standardization code (ISC) means a code assigned an item in the supply system which identifies the item as authorized...

  9. Does radioadaptive response also apply to the case of heavy-ion irradiations in fetal and adult mice?

    International Nuclear Information System (INIS)

    Possible induction of adaptive response (AR) by the high LET accelerated heavy ion irradiations (HI) is being attempted both in young adult female mice and in fetal mice of C57BL/6J Jms strain, using growth delay, hematopoietic damage and reduced survival in utero, prenatal growth delay, malformation and death in utero as endpoints. Investigations are to verify if priming dose from low LET X-irradiation could induce an AR against the detrimental effects from the high challenging dose of HI, if priming dose from HI could induce an AR against the high challenging dose from low LET X-irradiations, and if an AR could be induced when both priming and challenging doses are from HI. Three kinds of HI are being examined: carbon, silicon and iron, with the LET values of about 15, 55, and 200 keV/micrometer, respectively. Results show, at whole body level for the first time, that priming dose of low LET X-irradiations could induce AR both in vivo and in utero against the challenging dose from high LET HI, and priming dose from high LET HI could induce AR against the challenging dose from low LET X-irradiations in vivo. The remaining questions that if priming dose from HI could induce an AR against the challenging dose from low LET X-irradiations in ulero, if an AR could be induced both in vivo and in utero when both priming and challenging doses are from HI, and if there is any LET dependency in AR induction at whole body level, are still to be answered by further intensive investigations. (author)

  10. Does radioadaptive response also apply to the case of heavy-ion irradiations in fetal and adult mice?

    International Nuclear Information System (INIS)

    Possible induction of adaptive response (AR) by the high linear energy transfer (LET) accelerated heavy ion irradiations (HI) is being attempted both in young adult female mice and in fetal mice of C57BL/6J Jms strain, using growth delay, hematopoietic damage and reduced survival in vivo, prenatal growth delay, malformation and death in utero as endpoints. Investigations are to verify if priming dose from low LET X-irradiation could induce an AR against the detrimental effects from the high challenging dose of HI, if priming dose from HI could induce an AR against the high challenging dose from low LET X-irradiations, and if an AR could be induced when both priming and challenging doses are from HI. Four kinds of HI are being examined: carbon, neon, silicon and iron, with the LET values of about 15, 30, 55, and 200 keV/micrometer, respectively. Results show that the priming low dose X-irradiations could induce AR against high LET heavy-ion challenging irradiations from carbon and silicon beams in vivo and in utero, but not iron ions in vivo; the priming low dose carbon-ion irradiations could induce AR against the high challenging irradiations in vivo from X-rays or carbon ions, but not silicon and iron ions; priming dose from carbon, silicon or iron ions could not induce any AR against challenging dose from X-rays in utero. It seems that AR induction at whole body level is radiation quality-related event. Further investigations are needed to answer if this event is of LET- or/and nuclide-dependency. (author)

  11. Managing suspect and counterfeit items in the nuclear industry

    International Nuclear Information System (INIS)

    Some manufacturers and suppliers use inferior materials and processes to make substandard supplies whose properties can vary significantly from established standards and specifications. Other suppliers distribute items that they know do not meet the purchase requirements or provide documentation that misrepresent actual conformance to established specifications and standards. These substandard supplies, or suspect/counterfeit items (S/CIs), pose potential threats to the safety of workers, the public and the environment and may also have a detrimental effect on security and operations at nuclear facilities. Nuclear facilities often procure and use commercial-grade items and the quality assurance policies/procedures and procurement methods are not always properly applied to avoid the entry of S/Cls into those facilities. This publication offers practical guidance on how to apply existing quality assurance programmes to effectively prevent the procurement and use of S/Cls. In particular, it provides a practical method of applying the requirements and guidance contained in the IAEA Safety Series 50-C/SG-Q: Code and Safety Guides on Quality Assurance for Safety in Nuclear Power Plants and other Nuclear Installations (1996), to the S/CIs issue

  12. Quantitative Analysis of Complex Multiple-Choice Items in Science Technology and Society: Item Scaling

    Directory of Open Access Journals (Sweden)

    Ángel Vázquez Alonso

    2005-05-01

    Full Text Available The scarce attention to assessment and evaluation in science education research has been especially harmful for Science-Technology-Society (STS education, due to the dialectic, tentative, value-laden, and controversial nature of most STS topics. To overcome the methodological pitfalls of the STS assessment instruments used in the past, an empirically developed instrument (VOSTS, Views on Science-Technology-Society have been suggested. Some methodological proposals, namely the multiple response models and the computing of a global attitudinal index, were suggested to improve the item implementation. The final step of these methodological proposals requires the categorization of STS statements. This paper describes the process of categorization through a scaling procedure ruled by a panel of experts, acting as judges, according to the body of knowledge from history, epistemology, and sociology of science. The statement categorization allows for the sound foundation of STS items, which is useful in educational assessment and science education research, and may also increase teachers’ self-confidence in the development of the STS curriculum for science classrooms.

  13. 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...

  14. Item versus System Learning: Explaining Free Variation.

    Science.gov (United States)

    Ellis, Rod

    1999-01-01

    Provides an explanation for the existence of free variation in learner language. Argues that interlanguage is best conceptualized as sets of loose lexical networks that are gradually reorganized into a system or systems. Free variation arises when learners add items to those they have already acquired and before they analyze these items and…

  15. 76 FR 60474 - Commercial Item Handbook

    Science.gov (United States)

    2011-09-29

    ... Defense Acquisition Regulations System Commercial Item Handbook AGENCY: Defense Acquisition Regulations... Commercial Item Handbook. The purpose of the Handbook is to help acquisition personnel develop sound business... the Handbook. DATES: Comments should be submitted in writing to the address shown below on or...

  16. 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...

  17. 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.

  18. How Important Are Items on a Student Evaluation? A Study of Item Salience

    Science.gov (United States)

    Hills, Stacey Barlow; Naegle, Natali; Bartkus, Kenneth R.

    2009-01-01

    Although student evaluations of teaching (SETs) have been the subject of numerous research studies, the salience of SET items to students has not been examined. In the present study, the authors surveyed 484 students from a large public university. The authors suggest that not all items are viewed equally and that measures of item salience can…

  19. Designing P-Optimal Item Pools in Computerized Adaptive Tests with Polytomous Items

    Science.gov (United States)

    Zhou, Xuechun

    2012-01-01

    Current CAT applications consist of predominantly dichotomous items, and CATs with polytomously scored items are limited. To ascertain the best approach to polytomous CAT, a significant amount of research has been conducted on item selection, ability estimation, and impact of termination rules based on polytomous IRT models. Few studies…

  20. Selection of material balance areas and item control areas

    International Nuclear Information System (INIS)

    Section 70.58, ''Fundamental Nuclear Material Controls,'' of 10 CFR Part 70, ''Special Nuclear Material,'' requires certain licensees authorized to possess more than one effective kilogram of special nuclear material to establish Material Balance Areas (MBAs) or Item Control Areas (ICAs) for the physical and administrative control of nuclear materials. This section requires that: (1) each MBA be an identifiable physical area such that the quantity of nuclear material being moved into or out of the MBA is represented by a measured value; (2) the number of MBAs be sufficient to localize nuclear material losses or thefts and identify the mechanisms; (3) the custody of all nuclear material within an MBA or ICA be the responsibility of a single designated individual; and (4) ICAs be established according to the same criteria as MBAs except that control into and out of such areas would be by item identity and count for previously determined special nuclear material quantities, the validity of which must be ensured by tamper-safing unless the items are sealed sources. This guide describes bases acceptable to the NRC staff for the selection of material balance areas and item control areas. (U.S.)

  1. Effect of Applied Potential on the Formation of Self-Organized TiO2 Nanotube Arrays and Its Photoelectrochemical Response

    Directory of Open Access Journals (Sweden)

    Chin Wei Lai

    2011-01-01

    Full Text Available Self-organized TiO2 nanotube arrays have been fabricated by anodization of Ti foil in an electrochemical bath consisting of 1 M of glycerol with 0.5 wt% of NH4F. The effects of applied potential on the resulting nanotubes were illustrated. Among all of the applied potentials, 30 V resulted in the highest uniformity and aspect ratio TiO2 nanotube arrays with the tube's length approximately 1 μm and pore's size of 85 nm. TiO2 nanotube arrays were amorphous in as-anodized condition. The anatase phase was observed after annealing at 400∘C in air atmosphere. The effect of crystallization and effective surface area of TiO2 nanotube arrays in connection with the photoelectrochemical response was reported. Photoelectrochemical response under illumination was enhanced by using the annealed TiO2 nanotube arrays which have larger effective surface area to promote more photoinduced electrons.

  2. Effects of topically-applied olive oil on the response of hamster skin to single or multiple doses of 230 kV X-rays

    International Nuclear Information System (INIS)

    The effects of topically-applied olive oil on the response of hamster skin to single or multiple doses of X-rays has been studied. The olive oil was applied either 15 min or 1 hour before the radiation exposures. The treatment did not alter the temporal pattern of development and recovery from the radiation injury. For single exposures, olive oil did not alter the 1-to-30 day average skin response. However, when it was administered at each treatment when three radiation fractions were given over a 4-day interval (3 fractions/4 days), a significant increase in the amount of dose recovered was found compared with control irradiated animals. For controls, the average amount of dose recovered per fractionation interval, (Dsub(n) - Dsub(l)/(n-1), was about 505 rad. For animals treated with olive oil 15 min before irradiation, it was about 720 rad; and for those treated 1 hour before irradiation, it was 782 rad. The data indicated a definite radioprotective effect of topical administration of olive oil, but at present the mechanism is not known. (author)

  3. Reliability, Validity, and Predictive Utility of the 25-Item Criminogenic Cognitions Scale (CCS).

    Science.gov (United States)

    Tangney, June Price; Stuewig, Jeffrey; Furukawa, Emi; Kopelovich, Sarah; Meyer, Patrick; Cosby, Brandon

    2012-10-01

    Theory, research, and clinical reports suggest that moral cognitions play a role in initiating and sustaining criminal behavior. The 25 item Criminogenic Cognitions Scale (CCS) was designed to tap 5 dimensions: Notions of entitlement; Failure to Accept Responsibility; Short-Term Orientation; Insensitivity to Impact of Crime; and Negative Attitudes Toward Authority. Results from 552 jail inmates support the reliability, validity, and predictive utility of the measure. The CCS was linked to criminal justice system involvement, self-report measures of aggression, impulsivity, and lack of empathy. Additionally, the CCS was associated with violent criminal history, antisocial personality, and clinicians' ratings of risk for future violence and psychopathy (PCL:SV). Furthermore, criminogenic thinking upon incarceration predicted subsequent official reports of inmate misconduct during incarceration. CCS scores varied somewhat by gender and race. Research and applied uses of CCS are discussed. PMID:24072946

  4. Comparisons of methamphetamine psychotic and schizophrenic symptoms: a differential item functioning analysis.

    Science.gov (United States)

    Srisurapanont, Manit; Arunpongpaisal, Suwanna; Wada, Kiyoshi; Marsden, John; Ali, Robert; Kongsakon, Ronnachai

    2011-06-01

    The concept of negative symptoms in methamphetamine (MA) psychosis (e.g., poverty of speech, flatten affect, and loss of drive) is still uncertain. This study aimed to use differential item functioning (DIF) statistical techniques to differentiate the severity of psychotic symptoms between MA psychotic and schizophrenic patients. Data of MA psychotic and schizophrenic patients were those of the participants in the WHO Multi-Site Project on Methamphetamine-Induced Psychosis (or WHO-MAIP study) and the Risperidone Long-Acting Injection in Thai Schizophrenic Patients (or RLAI-Thai study), respectively. To confirm the unidimensionality of psychotic syndromes, we applied the exploratory and confirmatory factor analyses (EFA and CFA) on the eight items of Manchester scale. We conducted the DIF analysis of psychotic symptoms observed in both groups by using nonparametric kernel-smoothing techniques of item response theory. A DIF composite index of 0.30 or greater indicated the difference of symptom severity. The analyses included the data of 168 MA psychotic participants and the baseline data of 169 schizophrenic patients. For both data sets, the EFA and CFA suggested a three-factor model of the psychotic symptoms, including negative syndrome (poverty of speech, psychomotor retardation and flatten/incongruous affect), positive syndrome (delusions, hallucinations and incoherent speech) and anxiety/depression syndrome (anxiety and depression). The DIF composite indexes comparing the severity differences of all eight psychotic symptoms were lower than 0.3. The results suggest that, at the same level of syndrome severity (i.e., negative, positive, and anxiety/depression syndromes), the severity of psychotic symptoms, including the negative ones, observed in MA psychotic and schizophrenic patients are almost the same. PMID:21277930

  5. Psychometric evaluation and predictive validity of Ryffs psychological well-being items in a UK birth cohort sample of women

    OpenAIRE

    Wadsworth Michael EJ; Kuh Diana; Huppert Felicia A; Ploubidis George B; Abbott Rosemary A; Croudace Tim J

    2006-01-01

    Abstract Background Investigations of the structure of psychological well-being items are useful for advancing knowledge of what dimensions define psychological well-being in practice. Ryff has proposed a multidimensional model of psychological well-being and her questionnaire items are widely used but their latent structure and factorial validity remains contentious. Methods We applied latent variable models for factor analysis of ordinal/categorical data to a 42-item version of Ryff's psych...

  6. Translation of Transylvanian Culture-Specific Items into English

    Directory of Open Access Journals (Sweden)

    Kémenes Árpád

    2015-12-01

    Full Text Available The present paper focuses on some difficulties encountered during the translation of culture-specific items in Zsuzsa Tapodi’s articles Links between the East and the West: Historical Bonds between the Hungarians and the Balkan Peoples and Hungarian Ethnographic Region in Romania, published in the May 2014 issue of Carmina Balcanica. As far as the theoretical framework adopted in this study is concerned, the terminology on translation strategies relies on the taxonomy developed by Aixelá (1996, while the classification of culture-specific items has been influenced by Dimitriu (2002 and Yılmaz-Gümüş (2012. The study provides a definition of the term ‘culture-specific item’, considers the targetreaders’ awareness of source-language culture, and presents a number of translation strategies applied to mediate culture-bound information between the source and target cultures.

  7. Ion beam studies of archaeological gold jewellery items

    Science.gov (United States)

    Demortier, G.

    1996-06-01

    Analytical work on material of archaeological interest performed at LARN mainly concerns gold jewellery, with an emphasis to solders on the artefacts and to gold plating or copper depletion gilding. PIXE, RBS but also PIGE and NRA have been applied to a large variety of items. On the basis of elemental analysis, we have identified typical workmanship of ancient goldsmiths in various regions of the world: finely decorated Mesopotamian items, Hellenistic and Byzantine craftsmanship, cloisonne of the Merovingian period, depletion gilding on Pre-Colombian tumbaga. This paper is some shortening of the work performed at LARN during the last ten years. Criteria to properly use PIXE for quantitative analysis of non-homogeneous ancient artefacts presented at the 12th IBA conference in 1995 are also shortly discussed.

  8. Ion beam studies of archaeological gold jewellery items

    International Nuclear Information System (INIS)

    Analytical work on material of archaeological interest performed at LARN mainly concerns gold jewellery, with an emphasis to solders on the artefacts and to gold plating or copper depletion gilding. PIXE, RBS but also PIGE and NRA have been applied to a large variety of items. On the basis of elemental analysis, we have identified typical workmanship of ancient goldsmiths in various regions of the world: finely decorated Mesopotamian items, Hellenistic and Byzantine craftsmanship, cloisonne of the Merovingian period, depletion gilding on Pre-Colombian tumbaga. This paper is some shortening of the work performed at LARN during the last ten years. Criteria to properly use PIXE for quantitative analysis of non-homogeneous ancient artefacts presented at the 12th IBA conference in 1995 are also shortly discussed. (orig.)

  9. Ion beam studies of archaeological gold jewellery items

    Energy Technology Data Exchange (ETDEWEB)

    Demortier, G. [Facultes Universitaires Notre-Dame de la Paix, Namur (Belgium). Lab. d`Analyses par Reactions Nucleaires

    1996-06-01

    Analytical work on material of archaeological interest performed at LARN mainly concerns gold jewellery, with an emphasis to solders on the artefacts and to gold plating or copper depletion gilding. PIXE, RBS but also PIGE and NRA have been applied to a large variety of items. On the basis of elemental analysis, we have identified typical workmanship of ancient goldsmiths in various regions of the world: finely decorated Mesopotamian items, Hellenistic and Byzantine craftsmanship, cloisonne of the Merovingian period, depletion gilding on Pre-Colombian tumbaga. This paper is some shortening of the work performed at LARN during the last ten years. Criteria to properly use PIXE for quantitative analysis of non-homogeneous ancient artefacts presented at the 12th IBA conference in 1995 are also shortly discussed. (orig.).

  10. Watch - a low-cost, secure-item monitoring system

    International Nuclear Information System (INIS)

    Sandia National Laboratories has developed a remote sensor package that provides a low-cost, convenient way of monitoring item movement. Originally, the package was intended for use in valve monitoring, but it is now possible to use it in any sensor application where hardwire installation is impractical or uneconomical. Full system implementation includes a receiver/controller which correlates the arrival time of RF signals generated by item-monitoring transmitters to increase communication security. Wireless Alarm Transmission of Contained Handling (WATCH) is such a system. One important application of WATCH is in storage vaults where there are a number of material containers. Applying WATCH to inventory control reduces inventory workload and employee exposure rates; the system also provides quick access to inventory information by interfacing the system with plant site computer systems

  11. Blooms' separation of the final exam of Engineering Mathematics II: Item reliability using Rasch measurement model

    Science.gov (United States)

    Fuaad, Norain Farhana Ahmad; Nopiah, Zulkifli Mohd; Tawil, Norgainy Mohd; Othman, Haliza; Asshaari, Izamarlina; Osman, Mohd Hanif; Ismail, Nur Arzilah

    2014-06-01

    In engineering studies and researches, Mathematics is one of the main elements which express physical, chemical and engineering laws. Therefore, it is essential for engineering students to have a strong knowledge in the fundamental of mathematics in order to apply the knowledge to real life issues. However, based on the previous results of Mathematics Pre-Test, it shows that the engineering students lack the fundamental knowledge in certain topics in mathematics. Due to this, apart from making improvements in the methods of teaching and learning, studies on the construction of questions (items) should also be emphasized. The purpose of this study is to assist lecturers in the process of item development and to monitor the separation of items based on Blooms' Taxonomy and to measure the reliability of the items itself usingRasch Measurement Model as a tool. By using Rasch Measurement Model, the final exam questions of Engineering Mathematics II (Linear Algebra) for semester 2 sessions 2012/2013 were analysed and the results will provide the details onthe extent to which the content of the item providesuseful information about students' ability. This study reveals that the items used in Engineering Mathematics II (Linear Algebra) final exam are well constructed but the separation of the items raises concern as it is argued that it needs further attention, as there is abig gap between items at several levels of Blooms' cognitive skill.

  12. A Strategy for Optimizing Item-Pool Management

    NARCIS (Netherlands)

    Ariel, Adelaide; Linden, van der Wim 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 prod

  13. Cognitive interviewing methodology in the development of a pediatric item bank: a patient reported outcomes measurement information system (PROMIS study

    Directory of Open Access Journals (Sweden)

    DeWalt Darren A

    2009-01-01

    Full Text Available Abstract Background The evaluation of patient-reported outcomes (PROs in health care has seen greater use in recent years, and methods to improve the reliability and validity of PRO instruments are advancing. This paper discusses the cognitive interviewing procedures employed by the Patient Reported Outcomes Measurement Information System (PROMIS pediatrics group for the purpose of developing a dynamic, electronic item bank for field testing with children and adolescents using novel computer technology. The primary objective of this study was to conduct cognitive interviews with children and adolescents to gain feedback on items measuring physical functioning, emotional health, social health, fatigue, pain, and asthma-specific symptoms. Methods A total of 88 cognitive interviews were conducted with 77 children and adolescents across two sites on 318 items. From this initial item bank, 25 items were deleted and 35 were revised and underwent a second round of cognitive interviews. A total of 293 items were retained for field testing. Results Children as young as 8 years of age were able to comprehend the majority of items, response options, directions, recall period, and identify problems with language that was difficult for them to understand. Cognitive interviews indicated issues with item comprehension on several items which led to alternative wording for these items. Conclusion Children ages 8–17 years were able to comprehend most item stems and response options in the present study. Field testing with the resulting items and response options is presently being conducted as part of the PROMIS Pediatric Item Bank development process.

  14. Developing a Model for Optimizing Inventory of Repairable Items at Single Operating Base

    OpenAIRE

    Le, Tin

    2016-01-01

    The use of EOQ model in inventory management is popular. However, EOQ models has many disadvantages, especially, when the model is applied to manage repairable items. In order to deal with high-cost and repairable items, Craig C. Sherbrooke introduced a model in his book “Optimal Inventory Modeling of Systems: Multi-Echelon Techniques”. The research focus is to implement and develop a program to execute the single-site in-ventory model for repairable items. The model helps to significantl...

  15. 不同认知成分在图形推理测验项目难度预测中的作用%The Role of Different Cognitive Components in the Prediction of the Figural Reasoning Test's Item Difficulty

    Institute of Scientific and Technical Information of China (English)

    李中权; 王力; 张厚粲; 周仁来

    2011-01-01

    Figural reasoning tests (as represented by Raven's tests) are widely applied as effective measures of fluid intelligence in recruitment and personnel selection. However, several studies have revealed that those tests are not appropriate anymore due to high item exposure rates. Computerized automatic item generation (AIG) has gradually been recognized as a promising technique in handling item exposure. Understanding sources of item variation constitutes the initial stage of Computerized AIG, that is, searching for the underlying processing components and the stimuli that significantly influence those components. Some studies have explored sources of item variation, but so far there are no consistent results. This study investigated the relation between item difficulties and stimuli factors (e.g., familiarity of figures, abstraction of attributes, perceptual organization, and memory load) and determines the relative importance of those factors in predicting item difficulities.Eight sets of figural reasoning tests (each set containing 14 items imitating items from Raven's Advanced Progressive Matrics, APM) were constructed manipulating the familiarity of figures, the degree of abstraction of attributes, the perceptual organization as well as the types and number of rules. Using anchor-test design, these tests were administrated via the internet to 6323 participants with 10 items drawing from APAM as anchor items; thus, each participant completed 14 items from either one set and 10 anchor items within half an hour. In order to prevent participants from using response elimination strategy, we presented one item stem first, then alternatives in turn, and asked participants to determine which alternative was the best.DIMTEST analyses were conducted on the participants' responses on each of eight tests. Results showed that items measure a single dimension on each test. Likelihood ratio test indicated that the data fit two-parameter logistic model (2PL) best. Items were

  16. Quantification of the response delay of mobile radon-in-air detectors applied for detecting short-term fluctuations of radon-in-water concentrations

    International Nuclear Information System (INIS)

    Radon-in-water concentration time-series that are detected by means of radon-in-air detectors usually demonstrate a distinct response delay between radon-in-water concentration and the related radon-in-air records. This response delay results in recorded radon-in-air time-series that are not fully reflecting short-term radon-in-water fluctuations. The response delay is due to (i) the water/air transfer kinetics of radon and (ii) the delayed decay equilibrium between 222Rn and its progeny 218Po, which is actually being measured by most radon-in-air monitors. In the discussed study we designed a laboratory experiment with a defined radon-in-water input function, recorded the radon-in-air response signal and analysed the two time-series. Radon-in-air records showed a delay of about 10 min relative to the radon-in-water concentrations. However, for reconstructing the original radon-in-water signal based on the detected radon-in-air time-series we developed a numerical model considering all delay causing parameters. It was shown that the applied model allows reconstructing the input signal without any time delay and with correct concentrations for all concentration fluctuations lasting longer than about 10 min. In conclusion we can state that the developed numerical model allows a precise determination of radon-in-water concentration time-series based on radon-in-air records even if short-term fluctuations (>10 min) occur. (authors)

  17. 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...

  18. 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...

  19. Reminiscence and item recovery in free recall.

    Science.gov (United States)

    Madigan, S

    1976-05-01

    The item recovery or reminiscence component of recall in RTT procedures was investigated in two free recall experiments. In the first, Erdelyi and Becker's (1974) "hypermnesia" effect was found with pictures as the to-be-remembered material: total amount recalled increased over two successive test trials, and included a large reminiscence effect, with some 27% of previously unrecalled items appearing in the second test. The second experiment, with word lists, showed that the frequency of occurrence of new items was greater following a 12-min separation of two test trials than in two relatively massed tests. This kind of item recovery is relevant to models of output interference and retrieval limitations in free recall, and may be also related to spontaneous recovery effects. PMID:21287027

  20. The Analysis of The Multiple Choice Item

    Institute of Scientific and Technical Information of China (English)

    曹吴惠

    2009-01-01

    In this article, the author analyzes in detail the advantages, disadvantages and forming of the multiple choice item in examinations. On its basis, the author also exploree some aspects the teacher should pay attention to while setting an examination paper.

  1. Evaluating commercial-grade replacement items

    International Nuclear Information System (INIS)

    A nuclear power plant uses thousands of replacement items during its lifetime. When many suppliers abandoned their quality assurance programs during the plant construction slowdown of the early 1980s, an EPRI-sponsored utility group called NCIG developed guidelines to help utilities evaluate replacement items themselves. However, the need became clear for greater collaboration. Thus EPRI established the Joint Utility Task Group (JUTG) to pool utilities' resources and develop criteria for dedicating commercial-grade items for safety-related nuclear applications. So far, the JUTG has developed a generic evaluation process and completed technical evaluations of 56 replacement items. The resulting information is available in an on-line database through EPRINET

  2. Gender differences in national assessment of educational progress science items: What does i don't know really mean?

    Science.gov (United States)

    Linn, Marcia C.; de Benedictis, Tina; Delucchi, Kevin; Harris, Abigail; Stage, Elizabeth

    The National Assessment of Educational Progress Science Assessment has consistently revealed small gender differences on science content items but not on science inquiry items. This assessment differs from others in that respondents can choose I don't know rather than guessing. This paper examines explanations for the gender differences including (a) differential prior instruction, (b) differential response to uncertainty and use of the I don't know response, (c) differential response to figurally presented items, and (d) different attitudes towards science. Of these possible explanations, the first two received support. Females are more likely to use the I don't know response, especially for items with physical science content or masculine themes such as football. To ameliorate this situation we need more effective science instruction and more gender-neutral assessment items.

  3. An analysis of the differential item function through Mantel-Haenszel, SIBTEST and Logistic Regression Methods

    Directory of Open Access Journals (Sweden)

    Süleyman Demir

    2014-04-01

    Full Text Available This study performs a Differential Item Function (DIF analysis in terms of gender and culture on the items available in the PISA 2009 mathematics literacy sub-test. The DIF analyses were done through the Mantel Haenszel, Logistic Regression and the SIBTEST methods. The data for the gender variable were collected from the responses given by 332 students to the items in the mathematics literacy sub-test during the administration of the 5th booklet in the PISA 2009 application whereas the data for the culture variable were collected through the application of the 5th booklet in Turkey, Germany, Finland and the United States in the PISA 2009 application. As a result of DIF analysis according to gender, 4 items carried out in favor of men, only one item can be said to be advantageous in favor of girls. As a result of DIF analysis according to culture, 16 items for Turkish and German students, 14 items for Turkish and Finn students, 18 items for Turkish and United States students were determined.

  4. Techniques for reducing error in the calorimetric measurement of low wattage items

    Energy Technology Data Exchange (ETDEWEB)

    Sedlacek, W.A.; Hildner, S.S.; Camp, K.L.; Cremers, T.L.

    1993-08-01

    The increased need for the measurement of low wattage items with production calorimeters has required the development of techniques to maximize the precision and accuracy of the calorimeter measurements. An error model for calorimetry measurements is presented. This model is used as a basis for optimizing calorimetry measurements through baseline interpolation. The method was applied to the heat measurement of over 100 items and the results compared to chemistry assay and mass spectroscopy.

  5. On the impact of missing values on item fit and the model validness of the Rasch model

    Directory of Open Access Journals (Sweden)

    Klaus D. Kubinger

    2011-09-01

    Full Text Available A crucial point regarding the development and calibration of an aptitude test is the presence of missing values. In most test administrations, examinees omit individual items even in high-stakes tests. The most common procedure for treating these missing values in data analysis is to score these responses as incorrect; however, an alternative would be to consider omitted responses as if they were not administered to the examinee in question. Previous research has found that both procedures for dealing with missing values result in bias in item and person parameter estimation. Regarding test construction, not only is there an interest in item parameter estimation, but also in global and item-specific model tests as well as goodness-of-fit indices. On the basis of such statistics, it will be decided which items constitute the final item pool of a test. The present study therefore investigates the influence of two different procedures for dealing with missing values on model and item-specific tests as well as item fit indices for the Rasch model. The impact of these different treatment alternatives is shown for an empirical example and, furthermore, for simulated data. Simulations reveal that the global model test, as well as the item test, is affected by the procedures used to deal with missing values. To summarize, the results indicate that scoring omitted items as incorrect leads to seriously biased results.

  6. When Social Influence Meets Item Inference

    OpenAIRE

    Hung, Hui-Ju; Shuai, Hong-Han; Yang, De-Nian; Huang, Liang-Hao; Lee, Wang-Chien; Pei, Jian; Chen, Ming-Syan

    2015-01-01

    Research issues and data mining techniques for product recommendation and viral marketing have been widely studied. Existing works on seed selection in social networks do not take into account the effect of product recommendations in e-commerce stores. In this paper, we investigate the seed selection problem for viral marketing that considers both effects of social influence and item inference (for product recommendation). We develop a new model, Social Item Graph (SIG), that captures both ef...

  7. New developments in reprocessing semicritical items.

    Science.gov (United States)

    Rutala, William A; Weber, David J

    2013-05-01

    Semicritical medical devices are defined as items that come into contact with mucous membranes or nonintact skin (eg, gastrointestinal endoscopes). Such medical devices require minimally high-level disinfection. Because many of these items are temperature sensitive, low-temperature chemical methods must be used rather than steam sterilization. Strict adherence to current guidelines is required because more outbreaks have been linked to inadequately cleaned or disinfected endoscopes undergoing high-level disinfection than any other medical device. PMID:23622752

  8. Cultural Consensus Theory: Aggregating Continuous Responses in a Finite Interval

    Science.gov (United States)

    Batchelder, William H.; Strashny, Alex; Romney, A. Kimball

    Cultural consensus theory (CCT) consists of cognitive models for aggregating responses of "informants" to test items about some domain of their shared cultural knowledge. This paper develops a CCT model for items requiring bounded numerical responses, e.g. probability estimates, confidence judgments, or similarity judgments. The model assumes that each item generates a latent random representation in each informant, with mean equal to the consensus answer and variance depending jointly on the informant and the location of the consensus answer. The manifest responses may reflect biases of the informants. Markov Chain Monte Carlo (MCMC) methods were used to estimate the model, and simulation studies validated the approach. The model was applied to an existing cross-cultural dataset involving native Japanese and English speakers judging the similarity of emotion terms. The results sharpened earlier studies that showed that both cultures appear to have very similar cognitive representations of emotion terms.

  9. Influence of applied electric fields on the electron-related second and third-order nonlinear optical responses in two dimensional elliptic quantum dots

    Science.gov (United States)

    Giraldo-Tobón, Eugenio; Ospina, Walter; Miranda-Pedraza, Guillermo L.; Mora-Ramos, Miguel E.

    2015-07-01

    The coefficients of the second-order nonlinear optical rectification and the generation of second and third harmonics, related to electron energy transitions in a two-dimensional elliptical quantum dot are calculated. The conduction band states are obtained using the finite element method to numerically solve the effective mass Schrödinger differential equation in the parabolic approximation, including the influence of an externally applied static electric field. It comes about that the geometry of the ellipse has a strong influence on the optical response, being the large eccentricity case the more favorable one. Furthermore, it is shown that the application of an electric field is of most importance for achieving well-resolved higher harmonics signals.

  10. Structural changes in single membranes in response to an applied transmembrane electric potential revealed by time-resolved neutron/X-ray interferometry

    International Nuclear Information System (INIS)

    Highlights: ► Time-resolved (or transient) neutron/X-ray reflectivity. ► Neutron/X-ray reflectivity enhanced by interferometric techniques. ► Electric potential induced changes in a hybrid lipid bilayer membrane. ► Electric potential induced changes in a voltage-sensor protein membrane. - Abstract: The profile structure of a hybrid lipid bilayer, tethered to the surface of an inorganic substrate and fully hydrated with a bulk aqueous medium in an electrochemical cell, was investigated as a function of the applied transbilayer electric potential via time-resolved neutron reflectivity, enhanced by interferometry. Significant, and fully reversible structural changes were observed in the distal half (with respect to the substrate surface) of the hybrid bilayer comprised of a zwitterionic phospholipid in response to a +100 mV potential with respect to 0 mV. These arise presumably due to reorientation of the electric dipole present in the polar headgroup of the phospholipid and its resulting effect on the thickness of the phospholipid’s hydrocarbon chain layer within the hybrid bilayer’s profile structure. The profile structure of the voltage-sensor domain from a voltage-gated ion channel protein within a phospholipid bilayer membrane, tethered to the surface of an inorganic substrate and fully hydrated with a bulk aqueous medium in an electrochemical cell, was also investigated as a function of the applied transmembrane electric potential via time-resolved X-ray reflectivity, enhanced by interferometry. Significant, fully-reversible, and different structural changes in the protein were detected in response to ±100 mV potentials with respect to 0 mV. The approach employed is that typical of transient spectroscopy, shown here to be applicable to both neutron and X-ray reflectivity of thin films

  11. Single-Item Measurement of Suicidal Behaviors: Validity and Consequences of Misclassification.

    Science.gov (United States)

    Millner, Alexander J; Lee, Michael D; Nock, Matthew K

    2015-01-01

    Suicide is a leading cause of death worldwide. Although research has made strides in better defining suicidal behaviors, there has been less focus on accurate measurement. Currently, the widespread use of self-report, single-item questions to assess suicide ideation, plans and attempts may contribute to measurement problems and misclassification. We examined the validity of single-item measurement and the potential for statistical errors. Over 1,500 participants completed an online survey containing single-item questions regarding a history of suicidal behaviors, followed by questions with more precise language, multiple response options and narrative responses to examine the validity of single-item questions. We also conducted simulations to test whether common statistical tests are robust against the degree of misclassification produced by the use of single-items. We found that 11.3% of participants that endorsed a single-item suicide attempt measure engaged in behavior that would not meet the standard definition of a suicide attempt. Similarly, 8.8% of those who endorsed a single-item measure of suicide ideation endorsed thoughts that would not meet standard definitions of suicide ideation. Statistical simulations revealed that this level of misclassification substantially decreases statistical power and increases the likelihood of false conclusions from statistical tests. Providing a wider range of response options for each item reduced the misclassification rate by approximately half. Overall, the use of single-item, self-report questions to assess the presence of suicidal behaviors leads to misclassification, increasing the likelihood of statistical decision errors. Improving the measurement of suicidal behaviors is critical to increase understanding and prevention of suicide. PMID:26496707

  12. Single-Item Measurement of Suicidal Behaviors: Validity and Consequences of Misclassification.

    Directory of Open Access Journals (Sweden)

    Alexander J Millner

    Full Text Available Suicide is a leading cause of death worldwide. Although research has made strides in better defining suicidal behaviors, there has been less focus on accurate measurement. Currently, the widespread use of self-report, single-item questions to assess suicide ideation, plans and attempts may contribute to measurement problems and misclassification. We examined the validity of single-item measurement and the potential for statistical errors. Over 1,500 participants completed an online survey containing single-item questions regarding a history of suicidal behaviors, followed by questions with more precise language, multiple response options and narrative responses to examine the validity of single-item questions. We also conducted simulations to test whether common statistical tests are robust against the degree of misclassification produced by the use of single-items. We found that 11.3% of participants that endorsed a single-item suicide attempt measure engaged in behavior that would not meet the standard definition of a suicide attempt. Similarly, 8.8% of those who endorsed a single-item measure of suicide ideation endorsed thoughts that would not meet standard definitions of suicide ideation. Statistical simulations revealed that this level of misclassification substantially decreases statistical power and increases the likelihood of false conclusions from statistical tests. Providing a wider range of response options for each item reduced the misclassification rate by approximately half. Overall, the use of single-item, self-report questions to assess the presence of suicidal behaviors leads to misclassification, increasing the likelihood of statistical decision errors. Improving the measurement of suicidal behaviors is critical to increase understanding and prevention of suicide.

  13. An Application of Reverse Engineering to Automatic Item Generation: A Proof of Concept Using Automatically Generated Figures

    Science.gov (United States)

    Lorié, William A.

    2013-01-01

    A reverse engineering approach to automatic item generation (AIG) was applied to a figure-based publicly released test item from the Organisation for Economic Cooperation and Development (OECD) Programme for International Student Assessment (PISA) mathematical literacy cognitive instrument as part of a proof of concept. The author created an item…

  14. Gender differential item functioning on a national field-specific test: The case of PhD entrance exam of TEFL in Iran

    OpenAIRE

    Alireza Ahmadi; Ali Darabi Bazvand

    2016-01-01

    Differential Item Functioning (DIF) exists when examinees of equal ability from different groups have different probabilities of successful performance in a certain item. This study examined gender differential item functioning across the PhD Entrance Exam of TEFL (PEET) in Iran, using both logistic regression (LR) and one-parameter item response theory (1-p IRT) models. The PEET is a national test consisting of a centralized written examination designed to provide information on the eligibil...

  15. 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

    OpenAIRE

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

    2016-01-01

    BACKGROUND: 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 psych...

  16. 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

    OpenAIRE

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

    2016-01-01

    Background 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 psycho...

  17. Time-frequency analysis of laser Doppler flowmetry signals recorded in response to a progressive pressure applied locally on anaesthetized healthy rats

    Energy Technology Data Exchange (ETDEWEB)

    Humeau, Anne [Groupe ISAIP-ESAIP, 18 rue du 8 mai 1945, BP 80022, 49180 Saint Barthelemy d' Anjou Cedex (France); Koitka, Audrey [Laboratoire de Physiologie et d' Explorations Vasculaires, Centre Hospitalier Universitaire d' Angers, 49033 Angers Cedex 01 (France); Abraham, Pierre [Laboratoire de Physiologie et d' Explorations Vasculaires, Centre Hospitalier Universitaire d' Angers, 49033 Angers Cedex 01 (France); Saumet, Jean-Louis [Laboratoire de Physiologie et d' Explorations Vasculaires, Centre Hospitalier Universitaire d' Angers, 49033 Angers Cedex 01 (France); L' Huillier, Jean-Pierre [Ecole Nationale Superieure d' Arts et Metiers (ENSAM), Laboratoire Procedes-Materiaux-Instrumentation (LPMI), 2 boulevard du Ronceray, BP 3525, 49035 Angers Cedex (France)

    2004-03-07

    The laser Doppler flowmetry technique has recently been used to report a significant transient increase of the cutaneous blood flow signal, in response to a local non-noxious pressure applied progressively on the skin of both healthy humans and rats. This phenomenon is not entirely understood yet. In the present work, a time-frequency analysis is applied to signals recorded on anaesthetized healthy rats, at rest and during a cutaneous pressure-induced vasodilation (PIV). The comparison, at rest and during PIV, of the scalogram relative energies and scalogram relative amplitudes in five bands, corresponding to five characteristic frequencies, shows an increased contribution for the endothelial related metabolic activity in PIV signals, till 400 s after the beginning of the progressive pressure application. The other subsystems (heart, respiration, myogenic and neurogenic activities) contribute relatively less during PIV than at rest. The differences are statistically significant for all the relative activities in the interval 0-200 s following the beginning of the pressure. These results and others obtained on patients, such as diabetics, could increase the understanding of some cutaneous pathologies involved in various neurological diseases and in the pathophysiology of decubitus ulcers.

  18. Time-frequency analysis of laser Doppler flowmetry signals recorded in response to a progressive pressure applied locally on anaesthetized healthy rats

    International Nuclear Information System (INIS)

    The laser Doppler flowmetry technique has recently been used to report a significant transient increase of the cutaneous blood flow signal, in response to a local non-noxious pressure applied progressively on the skin of both healthy humans and rats. This phenomenon is not entirely understood yet. In the present work, a time-frequency analysis is applied to signals recorded on anaesthetized healthy rats, at rest and during a cutaneous pressure-induced vasodilation (PIV). The comparison, at rest and during PIV, of the scalogram relative energies and scalogram relative amplitudes in five bands, corresponding to five characteristic frequencies, shows an increased contribution for the endothelial related metabolic activity in PIV signals, till 400 s after the beginning of the progressive pressure application. The other subsystems (heart, respiration, myogenic and neurogenic activities) contribute relatively less during PIV than at rest. The differences are statistically significant for all the relative activities in the interval 0-200 s following the beginning of the pressure. These results and others obtained on patients, such as diabetics, could increase the understanding of some cutaneous pathologies involved in various neurological diseases and in the pathophysiology of decubitus ulcers

  19. Using Effect Sizes for Research Reporting: Examples Using Item Response Theory to Analyze Differential Item Functioning

    Science.gov (United States)

    Steinberg, Lynne; Thissen, David

    2006-01-01

    The psychological literature currently emphasizes reporting the "effect size" of research findings in addition to the outcome of any tests of significance. However, some confusion may result from the fact that there are three distinct uses of effect sizes in the psychological literature, namely, power analysis, research synthesis, and research…

  20. Evaluating the Mathematics Interest Inventory Using Item Response Theory: Differential Item Functioning across Gender and Ethnicities

    Science.gov (United States)

    Wei, Tianlan; Chesnut, Steven R.; Barnard-Brak, Lucy; Stevens, Tara; Olivárez, Arturo, Jr.

    2014-01-01

    As the United States has begun to lag behind other developed countries in performance on mathematics and science, researchers have sought to explain this with theories of teaching, knowledge, and motivation. We expand this examination by further analyzing a measure of interest that has been linked to student performance in mathematics and…

  1. Use of Robust z in Detecting Unstable Items in Item Response Theory Models

    Science.gov (United States)

    Huynh, Huynh; Meyer, Patrick

    2010-01-01

    The first part of this paper describes the use of the robust z[subscript R] statistic to link test forms using the Rasch (or one-parameter logistic) model. The procedure is then extended to the two-parameter and three-parameter logistic and two-parameter partial credit (2PPC) models. A real set of data was used to illustrate the extension. The…

  2. The effect of Trier Social Stress Test (TSST on item and associative recognition of words and pictures in healthy participants

    Directory of Open Access Journals (Sweden)

    Jonathan eGuez

    2016-04-01

    Full Text Available Psychological stress, induced by the Trier Social Stress Test (TSST, has repeatedly been shown to alter memory performance. Although factors influencing memory performance such as stimulus nature (verbal /pictorial and emotional valence have been extensively studied, results whether stress impairs or improves memory are still inconsistent. This study aimed at exploring the effect of TSST on item versus associative memory for neutral, verbal, and pictorial stimuli. 48 healthy subjects were recruited, 24 participants were randomly assigned to the TSST group and the remaining 24 participants were assigned to the control group. Stress reactivity was measured by psychological (subjective state anxiety ratings and physiological (Galvanic skin response recording measurements. Subjects performed an item-association memory task for both stimulus types (words, pictures simultaneously, before, and after the stress/non-stress manipulation. The results showed that memory recognition for pictorial stimuli was higher than for verbal stimuli. Memory for both words and pictures was impaired following TSST; while the source for this impairment was specific to associative recognition in pictures, a more general deficit was observed for verbal material, as expressed in decreased recognition for both items and associations following TSST. Response latency analysis indicated that the TSST manipulation decreased response time but at the cost of memory accuracy. We conclude that stress does not uniformly affect memory; rather it interacts with the task’s cognitive load and stimulus type. Applying the current study results to patients diagnosed with disorders associated with traumatic stress, our findings in healthy subjects under acute stress provide further support for our assertion that patients’ impaired memory originates in poor recollection processing following depletion of attentional resources.

  3. The Effect of Trier Social Stress Test (TSST) on Item and Associative Recognition of Words and Pictures in Healthy Participants.

    Science.gov (United States)

    Guez, Jonathan; Saar-Ashkenazy, Rotem; Keha, Eldad; Tiferet-Dweck, Chen

    2016-01-01

    Psychological stress, induced by the Trier Social Stress Test (TSST), has repeatedly been shown to alter memory performance. Although factors influencing memory performance such as stimulus nature (verbal/pictorial) and emotional valence have been extensively studied, results whether stress impairs or improves memory are still inconsistent. This study aimed at exploring the effect of TSST on item versus associative memory for neutral, verbal, and pictorial stimuli. 48 healthy subjects were recruited, 24 participants were randomly assigned to the TSST group and the remaining 24 participants were assigned to the control group. Stress reactivity was measured by psychological (subjective state anxiety ratings) and physiological (Galvanic skin response recording) measurements. Subjects performed an item-association memory task for both stimulus types (words, pictures) simultaneously, before, and after the stress/non-stress manipulation. The results showed that memory recognition for pictorial stimuli was higher than for verbal stimuli. Memory for both words and pictures was impaired following TSST; while the source for this impairment was specific to associative recognition in pictures, a more general deficit was observed for verbal material, as expressed in decreased recognition for both items and associations following TSST. Response latency analysis indicated that the TSST manipulation decreased response time but at the cost of memory accuracy. We conclude that stress does not uniformly affect memory; rather it interacts with the task's cognitive load and stimulus type. Applying the current study results to patients diagnosed with disorders associated with traumatic stress, our findings in healthy subjects under acute stress provide further support for our assertion that patients' impaired memory originates in poor recollection processing following depletion of attentional resources. PMID:27148117

  4. The Effect of Trier Social Stress Test (TSST) on Item and Associative Recognition of Words and Pictures in Healthy Participants

    Science.gov (United States)

    Guez, Jonathan; Saar-Ashkenazy, Rotem; Keha, Eldad; Tiferet-Dweck, Chen

    2016-01-01

    Psychological stress, induced by the Trier Social Stress Test (TSST), has repeatedly been shown to alter memory performance. Although factors influencing memory performance such as stimulus nature (verbal/pictorial) and emotional valence have been extensively studied, results whether stress impairs or improves memory are still inconsistent. This study aimed at exploring the effect of TSST on item versus associative memory for neutral, verbal, and pictorial stimuli. 48 healthy subjects were recruited, 24 participants were randomly assigned to the TSST group and the remaining 24 participants were assigned to the control group. Stress reactivity was measured by psychological (subjective state anxiety ratings) and physiological (Galvanic skin response recording) measurements. Subjects performed an item-association memory task for both stimulus types (words, pictures) simultaneously, before, and after the stress/non-stress manipulation. The results showed that memory recognition for pictorial stimuli was higher than for verbal stimuli. Memory for both words and pictures was impaired following TSST; while the source for this impairment was specific to associative recognition in pictures, a more general deficit was observed for verbal material, as expressed in decreased recognition for both items and associations following TSST. Response latency analysis indicated that the TSST manipulation decreased response time but at the cost of memory accuracy. We conclude that stress does not uniformly affect memory; rather it interacts with the task’s cognitive load and stimulus type. Applying the current study results to patients diagnosed with disorders associated with traumatic stress, our findings in healthy subjects under acute stress provide further support for our assertion that patients’ impaired memory originates in poor recollection processing following depletion of attentional resources.

  5. A sampling and classification item selection approach with content balancing.

    Science.gov (United States)

    Chen, Pei-Hua

    2015-03-01

    Existing automated test assembly methods typically employ constrained combinatorial optimization. Constructing forms sequentially based on an optimization approach usually results in unparallel forms and requires heuristic modifications. Methods based on a random search approach have the major advantage of producing parallel forms sequentially without further adjustment. This study incorporated a flexible content-balancing element into the statistical perspective item selection method of the cell-only method (Chen et al. in Educational and Psychological Measurement, 72(6), 933-953, 2012). The new method was compared with a sequential interitem distance weighted deviation model (IID WDM) (Swanson & Stocking in Applied Psychological Measurement, 17(2), 151-166, 1993), a simultaneous IID WDM, and a big-shadow-test mixed integer programming (BST MIP) method to construct multiple parallel forms based on matching a reference form item-by-item. The results showed that the cell-only method with content balancing and the sequential and simultaneous versions of IID WDM yielded results comparable to those obtained using the BST MIP method. The cell-only method with content balancing is computationally less intensive than the sequential and simultaneous versions of IID WDM. PMID:24610145

  6. Use of an Aquarium as a Novel Enrichment Item for Singly Housed Rhesus Macaques (Macaca mulatta)

    OpenAIRE

    Meade, Theresa M; Hutchinson, Eric; Krall, Caroline; Watson, Julie

    2014-01-01

    Locomotor stereotypies are behaviors often seen in singly housed rhesus macaques (Macaca mulatta) and are considered to represent a maladaptive response to captive environments. Active and passive enrichment items are commonly used to mitigate these and other abnormal behaviors. Active enrichment items allow physical manipulation and may be temporarily successful in reducing stereotypies, but their beneficial effects usually are confined to relatively short periods of active use. Passive enri...

  7. Item Bank Development for a Revised Pediatric Evaluation of Disability Inventory (PEDI)

    OpenAIRE

    Dumas, Helene M.; Fragala-Pinkham, Maria A.; Stephen M. Haley; Coster, Wendy J.; Kramer, Jessica M.; KAO, YING-CHIA; Moed, Richard

    2010-01-01

    The Pediatric Evaluation of Disability Inventory (PEDI) is a useful clinical and research assessment but it has limitations in content, age range and efficiency. The purpose of this article is to describe the process used to develop the item bank for a new computerized adaptive test version of the PEDI (PEDI-CAT). An expanded item set and response scales were reviewed by clinician experts and examined at parent and clinician focus groups. Eleven parents participated in 32 cognitive interviews...

  8. Clinical relevance of single item quality of life indicators in cancer clinical trials

    OpenAIRE

    Bernhard, J.; Sullivan, M.; Hürny, C; Coates, A S; Rudenstam, C-M

    2001-01-01

    We investigated the hypothesis that global single-item quality-of-life indicators are less precise for specific treatment effects (discriminant validity) than multi-item scales but similarly efficient for overall treatment comparisons and changes over time (responsiveness) because they reflect the summation of the individual meaning and importance of various factors. Linear analogue self-assessment (LASA) indicators for physical well-being, mood and coping were compared with the Hospital Anxi...

  9. 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.

  10. Performance-based evaluation of commercial-grade items

    International Nuclear Information System (INIS)

    For the last decade, regulatory expectations for the procurement process for nuclear safety-related commercial-grade items (CGIs) have increased. These changes are driven by US Nuclear Regulatory Commission (NRC) concern for fraudulent or misrepresented parts and significant marketplace changes. The industry responded to these concerns by developing improved procurement programs that changed the detail to which parts were specified and received and provided for verification of attributes that were critical to successful performance of safety-related function(s). Like its counterparts, Duquesne Light Company (DLCo) began applying enhanced program requirements to procurements initiated after September 1, 1989, in order to meet the industry's January 1, 1990, commitment

  11. Software for MUF evaluating in item nuclear material accounting

    International Nuclear Information System (INIS)

    Nuclear material accounting is a key measure for nuclear safeguard. Software for MUF evaluation in item nuclear material accounting was worked out in this paper. It is composed of several models, including input model, data processing model, data inquiring model, data print model, system setting model etc. It could be used to check the variance of the measurement and estimate the confidence interval according to the MUF value. To insure security of the data multi-user management function was applied in the software. (authors)

  12. Application of Item Analysis to Assess Multiple-Choice Examinations in the Mississippi Master Cattle Producer Program

    Science.gov (United States)

    Parish, Jane A.; Karisch, Brandi B.

    2013-01-01

    Item analysis can serve as a useful tool in improving multiple-choice questions used in Extension programming. It can identify gaps between instruction and assessment. An item analysis of Mississippi Master Cattle Producer program multiple-choice examination responses was performed to determine the difficulty of individual examinations, assess the…

  13. Applied Electromagnetics

    International Nuclear Information System (INIS)

    These proceedings contain papers relating to the 3rd Japanese-Bulgarian-Macedonian Joint Seminar on Applied Electromagnetics. Included are the following groups: Numerical Methods I; Electrical and Mechanical System Analysis and Simulations; Inverse Problems and Optimizations; Software Methodology; Numerical Methods II; Applied Electromagnetics

  14. Technical evaluation process for specifying replacement items

    International Nuclear Information System (INIS)

    As nuclear power plants continue in the transition to a strictly operating and maintenance mode, the engineering involvement required to specify and procure replacement parts and components continues to increase. The evaluation process for a replacement item has one simple goal: to specify an effective set of technical and quality requirements that will result in the procurement of an item meeting the plant design basis. The evaluation process is depicted in a simplified block diagram showing the elements of engineering evaluation from a functional perspective. These elements are the following: (1) need for a technical evaluation; (2) components and part classification; (3) failure mode and effect analysis (FMEA); (4) critical characteristics for design determination; (5) like-for-like or alternate item evaluation; and (6) technical and quality requirements determination

  15. 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.

  16. An Evaluation of Items and Dimensional Structure of a Scale to Measure Teachers’ Professional Commitment in Thailand

    Directory of Open Access Journals (Sweden)

    Jirawat Tansakul

    2015-05-01

    Full Text Available The purpose of this study was to examine the items and the dimensionality of a scale to measure professional commitment of teachers in Thailand. Data were collected by in-depth interview and questionnaire. The content analysis was conducted with the qualitative data for the purpose of item writing. Differential item functioning (DIF, exploratory factor analysis (EFA, confirmatory factor analysis (CFA, and bi-factor CFA model analysis were conducted to establish validity evidence. As a result of EFA and CFA, the study showed that a 3-dimensional scale can effectively measure professional commitment of teachers, which was achieved by the 18-item measure. A polytomuos item response theory model was also fitted to estimate item parameters and to examine the test information function.

  17. Positive and negative item wording and its influence on the assessment of callous-unemotional traits.

    Science.gov (United States)

    Ray, James V; Frick, Paul J; Thornton, Laura C; Steinberg, Laurence; Cauffman, Elizabeth

    2016-04-01

    [Correction Notice: An Erratum for this article was reported in Vol 28(4) of Psychological Assessment (see record 2015-33818-001). In the article, the sixth sentence of the second full paragraph in the Data Analyses subsection of the Method section should read "For k response categories, there are k-1 threshold parameters."] This study examined the item functioning of the Inventory of Callous-Unemotional Traits (ICU) in an ethnically diverse sample 1,190 of first-time justice-involved adolescents (mean age = 15.28 years, SD = 1.29). On elimination of 2 items, the total ICU score provided a reliable (internally consistent and stable) and valid (correlated with and predictive of measures of empathy, school conduct problems, delinquency, and aggression) continuous measure of callous and unemotional (CU) traits. A shortened, 10-item version of the total scale, developed from item response theory (IRT) analyses, appeared to show psychometric properties similar to those of the full ICU and, thus, could be used as an abbreviated measure of CU traits. Finally, item analyses and tests of validity suggested that the factor structure of the ICU reported in a large number of past studies could reflect method variance related to the ICU, including equal numbers of positively and negatively worded items. Specifically, positively worded items (i.e., items for which higher ratings are indicative of higher levels of CU traits) were more likely to be rated in the lower response categories, showed higher difficulty levels in IRT analyses (i.e., discriminated best at higher levels of CU traits), and were more highly correlated with measures of antisocial and aggressive behavior. On the basis of these findings, we recommend using the total ICU as a continuous measure of CU traits and do not recommend continued use of the subscale structure that has been reported in multiple past studies. (PsycINFO Database Record PMID:26121386

  18. MULTI-ITEM FAIR EXCHANGE SCHEME

    Institute of Scientific and Technical Information of China (English)

    Zheng Dong; Chen Kefei

    2002-01-01

    As more business is conduced over the Internet, the fair exchange problem assumes increasing importance. However, the problem of multi-party fair exchange has not been studied as widely as the more fundamental problem of 2-party fair exchange. Recently, Franklin and Tsudik proposed two protocols for n-party multi-item exchange on FC'98, SUCEX-1 and SUCES-2. This paper first gives an attack on the proposed protocol SUCEX-1, then presents two protocols for multi-item exchange, one is an improved protocol of SUCEX-1, another is the extension of protocol SUCEX-2.

  19. MULTI—ITEM FAIR EXCHANGE SCHEME

    Institute of Scientific and Technical Information of China (English)

    ZhengDong; ChenKefei

    2002-01-01

    As more ubsiness is conduced over the Internet,the fair exchange problem assumes increasing importance,However,the problem of multi-party fair exchange has not been studied as widely as the more fundamental problem of 2-party fair exchange,Recently,Franklin and Tsudik proposed two protocols for n-parth multi-item exchange on FC'98,SUCEX-1 and SUCES-2,This paper first gives an attack on the proposed protocol SUCEX-1,then presents two protocols for multi-item exchange,one is an improoved protocol of SUCEX-1,another is the extension of protocol SUCEX-2.

  20. 粗糙集在项目认知属性标定中的应用%Application of Rough Set Theory in Item Cognitive Attribute Identification

    Institute of Scientific and Technical Information of China (English)

    唐小娟; 丁树良; 俞宗火

    2015-01-01

    samples of subjects and items are necessary for CD-CAT to identify item attributes. The second limit of CD-CAT is that it is based on item pool, and the development of item pool is very expensive that the cost of one item is about $1000. Cognitive diagnosis is designed to provide information about students’ cognitive strengths and weaknesses and to assist the teaching. So, the best place to use it is in classrooms. But cognitive diagnosis is just used in lager–scale examinations now for two reasons: First, most cognitive diagnosis models are based on probability models which need a large sample in estimating item parameters, and the using of these cognitive diagnosis models are also based on a large sample of subjects even the items’ parameters have been estimated. Secondary, even though the method of CD-CAT can be used in a small–scale examination once the item parameters are known, CAT has been prohibited in many kinds of examinations for other reasons. So, it is very necessary to find a new method to indentify item attributes when item parameters are unknown, examinees are less and feedbacks are timely. In the current studies, we apply a new method – Rough Set Theory (RST) to ICAI. RST can solve the uncertainty in CD caused by the size of knowledge granularity. It doesn’t require any priori knowledge. Through the knowledge reduction, RST induces decision or classification rules, and then classifies the object. At first, we verificate the application of RST in ICAI. Then, in Study One, we explore how the match ratio of subjects' knowledge states and the slippage in subjects' responses to items impact the match ratio of item attributes. The number of item attributes is a variable which impacts the accuracy of CD, so, we also examine how the number of cognitive contributes impact the match ratio of item attributes. The results show that: (1) In the absence of item parameters, the rough set theory of ICAI has fast diagnostic speed and good results even though