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See detailAccuracy of asymptotic standard errors of the maximum and weighted likelihood estimators of proficiency levels with short tests
Magis, David ULg

in Applied Psychological Measurement (2014), 38

The maximum likelihood (ML) and the weighted likelihood (WL) estimators are commonly used to obtain proficiency level estimates with pre-calibrated item parameters. Both estimators have the same ... [more ▼]

The maximum likelihood (ML) and the weighted likelihood (WL) estimators are commonly used to obtain proficiency level estimates with pre-calibrated item parameters. Both estimators have the same asymptotic standard error (ASE) that can be easily derived from the expected information function of the test. However, the accuracy of this asymptotic formula is uncertain with short tests when only a few items are administered. The purpose of this paper is to compare the ASE of these estimators to their exact values, evaluated at the proficiency level estimates. The exact SE is computed by generating the full exact sample distribution of the estimators, so its practical feasibility is limited to small tests (except under the Rasch model). A simulation study was conducted to compare the ASE and the exact SE of the ML and WL estimators, to the “true” SE (i.e., computed as the exact SE with the true proficiency levels). It is concluded that with small tests, the exact SEs are less biased and return smaller root mean squared error values than the asymptotic SEs, while as expected the two estimators return similar results with longer tests. [less ▲]

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See detailUsing R for conducting psychometric research
Magis, David ULg

Scientific conference (2013, October 31)

R is a statistical environment that permits to perform many various analyses, from basic descriptive statistics to advanced and complex modeling through high-level graphical features. In addition, it is ... [more ▼]

R is a statistical environment that permits to perform many various analyses, from basic descriptive statistics to advanced and complex modeling through high-level graphical features. In addition, it is open-source software with thousands of users worldwide and with (almost) daily improvements by the development of additional packages. The purpose of this talk is twofold: (a) to provide a broad overview of R (in its basic form), RStudio (software for optimized display of R components) and R Commander (an add-on package with menus and toolboxes for R); and (b) to describe and illustrate the functioning of several R packages related to psychometrics in general and item response theory in particular. The talk will be at a theoretical low-level, focusing rather on applications and illustrations with examples. Topics to be covered may include (depending on time constraints): calibration of item response models, ability estimation, model checking, differential item functioning, computerized adaptive testing. Some information about the creation and compilation of R packages will also be given. References: R Core Team (2013). R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. URL http://www.R-project.org/. [less ▲]

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See detailAsymptotic distribution of robust estimators of ability and applications
Magis, David ULg

Scientific conference (2013, October 31)

In item response theory (IRT), ability estimation can be seriously affected by abnormal responses occurring from e.g., cheating, inattention, lack of time, guessing, tiredness, stress… Those phenomena may ... [more ▼]

In item response theory (IRT), ability estimation can be seriously affected by abnormal responses occurring from e.g., cheating, inattention, lack of time, guessing, tiredness, stress… Those phenomena may influence the ability estimation process tremendously. One the one hand, person fit indices were developed as post-hoc approaches to identify abnormal responses patterns as a whole (e.g., Meijer & Sijtsma, 2001). On the other hand, getting uncontaminated ability estimates would also be a challenging issue. Robust estimators were proposed in the IRT framework to lessen the impact of abnormal responses onto the estimation process (Mislevy & Bock, 1982; Schuster & Yuan, 2011; Wainer & Wright, 1980). Yet, these estimators are still rarely used in practice, mostly because very little is known about their statistical properties. The purpose of this talk is to briefly present these robust ability estimators, and to derive their asymptotic distribution under mild regularity conditions. In particular, a simple formula for the asymptotic standard error (ASE) of these estimators is obtained (Magis, in press). Results of a simulation study that involves both presence and absence of cheating in the data generation process will be outlined. References: Magis, D. (in press). On the asymptotic standard error of a class of robust estimators of ability in dichotomous item response models. British Journal of Mathematical and Statistical Psychology. Meijer, R., & Sijtsma, K. (2001). Methodology review: Evaluating person fit. Applied Psychological Measurement, 25, 107-135. doi: 10.1177/01466210122031957 Mislevy, R. J., & Bock, R. D. (1982). Biweight estimates of latent ability. Educational and Psychological Measurement, 42, 725-737. doi: 10.1177/001316448204200302 Schuster, C., & Yuan, K.-H. (2011). Robust estimation of latent ability in item response models. Journal of Educational and Behavioral Statistics, 36, 720-735. doi: 10.3102/1076998610396890 Wainer, H., & Wright, B. D. (1980). Robust estimation of ability in the Rasch model. Psychometrika, 45, 373-391. doi: 10.1007/BF02293910 [less ▲]

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See detailAsymptotic standard errors of robust estimators of ability in dichotomous item response models
Magis, David ULg

Conference (2013, October 10)

In item response theory, the classical estimators of ability are highly sensitive to response disturbances and can return strongly biased estimates of the true underlying ability level. Robust methods ... [more ▼]

In item response theory, the classical estimators of ability are highly sensitive to response disturbances and can return strongly biased estimates of the true underlying ability level. Robust methods were introduced to lessen the impact of such aberrant responses onto the estimation process. The computation of asymptotic (i.e., large sample) standard errors (ASE) for these robust estimators, however, has not been fully considered yet. This paper focuses on a broad class of robust ability estimators, de ned by an appropriate selection of the weight function and the residual measure, for which the ASE is derived from the theory of estimating equations. The maximum likelihood (ML) and the robust estimators, together with their estimated ASE, are then compared through a simulation study. It is concluded that both the estimators and their ASE perform similarly in absence of response disturbances, while the robust estimator and its estimated ASE are less biased and outperform their ML counterparts in presence of response disturbances with large impact on the item response process. [less ▲]

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See detailA small overview of available computer software to support computerized adaptive testing
Magis, David ULg

Conference (2013, August 27)

Computerized adaptive testing (CAT) is becoming a central tool for testing and assessment. It offers many advantages over fixed (“paper-and-pencil”) methods, such as individualized assessment, reduction ... [more ▼]

Computerized adaptive testing (CAT) is becoming a central tool for testing and assessment. It offers many advantages over fixed (“paper-and-pencil”) methods, such as individualized assessment, reduction of fraud, and straightforward estimation of proficiency levels. CAT has been studied for decades and remains an up-to-date research field in psychometrics and educational science. Practical CAT administration, however, is less frequently considered in such studies. Assigning CAT to respondents requires both the sufficient availability of computer machines, and the use of a powerful and easy-to-use CAT software. With the fast increase of computer resources at moderate cost, the availability of computer machines is becoming a less central, yet important, issue in the practical assessment of CAT tests. The choice of an accurate CAT software, on the other hand, should be guided by its flexibility, its underlying statistical modeling, and its user-friendly potential. According to the type of research or data analysis, some CAT software might be preferred to another. It is therefore important for the researcher or the clinician to know about the current availability of such software, in line with current research and practice in the CAT framework. Moreover, these software should allow enough flexibility to incorporate updates and new theoretical developments, such as e.g., new rules for next item selection. This talk proposes a simple and user-oriented presentation of several CAT software that are currently available. The software to be presented are: the Firestar software (Choi, 2009), the R package catR (Magis & Raîche, 2012), the R package catIrt (Nydick, 2012) and the CAT web-platform Concerto (Kosinski & Rust, 2011). The first three are non-commercial software, while Concerto is a web interface between end users (willing to develop computerized assessment tests) and catR (as underlying routine software). Both R packages are written to be most useful for researchers, without end-user interface, and are therefore less appealing for applied researchers who are not familiar with R. Yet, they offer flexible solutions by means of many options to optimize the design of the test and generate many response patterns for further analyses. Also, they can be easily integrated as sub-routines for more sophisticated CAT software. Firestar provides a user interface and makes all necessary computations with underlying R code. This talk aims at focusing on freely available CAT software. For this reason, only the four aforementioned programs will be presented, although it exists other, commercial CAT software such as e.g., the CATSim software (Assessment Systems Corporation, 2012). The different CAT software are briefly presented and their advantages and drawbacks, flexibility and usefulness are compared, mostly from the point of view of the applied researcher and clinician. The following criteria were retained for objective comparison: (a) their main goal of application; (b) the type of data and IRT modeling they can deal with; (c) the type of users they are focusing on; (d) their operating options; (e) their availability and flexibility for further improvements. A small demonstration of the R package catR will be proposed optionally, depending on time limitation. References Assessment Systems Corporation (2012). CATSim: Comprehensive simulation of computerized adaptive testing. St. Paul, MN. URL: http://www.assess.com/. Choi , S. W. (2009). Firestar: Computerized adaptive testing simulation program for polytomous item response theory models. Applied Psychological Measurement, 33, 644-645. Kosinski, M., & Rust, J. (2011). The development of Concerto: An open source online adaptive testing platform. Paper presented at the International Association for Computerized and Adaptive Testing (IACAT), Pacific Grove, CA. Magis, D., & Raîche, G. (2012). Random generation of response patterns under computerized adaptive testing with the R package catR. Journal of Statistical Software, 48, 1-31. Nydick, S. W. (2012). catIrt: An R package for simulating IRT-based computerized adaptive tests. R package version 0.3-0. [less ▲]

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See detailEquivalence of weighted likelihood and Jeffreys modal estimation of proficiency under polytomous item response models
Magis, David ULg

Conference (2013, July 23)

This talk focuses on two proficiency level estimators in item response theory (IRT) framework: the weighted likelihood estimator (WLE) and the Jeffreys modal estimator (JME), that is, the usual Bayes ... [more ▼]

This talk focuses on two proficiency level estimators in item response theory (IRT) framework: the weighted likelihood estimator (WLE) and the Jeffreys modal estimator (JME), that is, the usual Bayes modal estimator with Jeffreys’ non-informative prior. With dichotomously scored items, the WLE and the JME are completely equivalent under the two-parameter logistic model, while remarkable relationships were established under the three-parameter logistic model. The purpose of this talk is to extend such comparison to polytomously scored items. It is shown that both WLE and JME are also equivalent for two broad classes of polytomous IRT models, including, among others, the (modified) graded response model, the (generalized) partial credit model, the rating scale model and the nominal response model. Parallelisms with dichotomously scored items are drawn. An example from a real data set is used to illustrate this finding. [less ▲]

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See detailProposition de nouveaux indices de détection de patrons de réponses inappropriés dans le contexte des enquêtes et des épreuves d’évaluation des apprentissages
Béland, Sébastien; Raîche, Gilles; Magis, David ULg

Conference (2013, June 07)

Il n’est pas rare de voir des étudiants répondre de façon inappropriée à une épreuve d’évaluation comportant des items à réponses choisies. Par exemple, certains individus peuvent tricher alors que ... [more ▼]

Il n’est pas rare de voir des étudiants répondre de façon inappropriée à une épreuve d’évaluation comportant des items à réponses choisies. Par exemple, certains individus peuvent tricher alors que d’autres peuvent tenter de se sous-classer intentionnellement à un examen. Plusieurs approches ont été développées pour faire la détection de ce type d’étudiants. À ce jour, l’approche la plus prometteuse est l’utilisation d’indice de détection de type person‐fit (Meijer et Sijtsma, 2001). L’indice de détection lz (Drasgow, Levine et Williams, 1985) est fort probablement le plus utilisé et le plus connu d’entre tous. Malheureusement, cet indice est fortement affecté par le fait que l’habileté des étudiants est estimée et non pas réelle ; ce qui peut biaiser son calcul (Molenaar et Hoijtink, 1990). Pour pallier ce problème, Snijders (2001) a proposé une correction qui permet de diminuer considérablement le biais associé à la moyenne et à la variance de l’indice lz. Dans le cadre de notre projet doctoral, nous nous inspirerons de la suggestion de Snijders (2001) pour corriger deux autres indices de détection de patrons de réponses inappropriés : l’infit mean square (u) et l’outfit mean square (w). À cette fin, nous utiliserons une approche monte carliste afin d’investiguer plus en détails l’erreur de type 1 et la puissance de ces autres indices. Nos résultats préliminaires, que nous présenterons lors de cette communication, montrent que ces autres indices corrigés semblent eux aussi plus efficaces que leur version traditionnelle sans correction. [less ▲]

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See detailIntroduction to the R software
Magis, David ULg

Scientific conference (2013, May 08)

The R software (R Core Development Team, 2012) is an open-source statistical software that allows data handling, statistical analyses and model fitting, , and graphical representations, among others. It ... [more ▼]

The R software (R Core Development Team, 2012) is an open-source statistical software that allows data handling, statistical analyses and model fitting, , and graphical representations, among others. It is very flexible and has lots of pre-installed statistical methods. It is working under all operating systems, including Windows, Linux/UNIX and MacOS. The R community is worldwide and proposes free exchanges of shared R packages through the CRAN (comprehensive R archive network). However, the user needs some practice to become familiar with the software, as it does not have easy to use interface, yet. The purpose of this workshop is to illustrate some aspects of this software with applied purposes. A data set from the field of clinical psychology will be considered throughout the workshop as an illustrative example. Data loading in R, data manipulation, summary and simple statistics, graphics, basic (t-tests, ANOVA, …) and advanced (factor analysis, generalized linear modeling, item response theory, …) statistical analyses will be described and illustrated. Live demonstrations will be run and participants will be encouraged to practice during the workshop. Participants are required to bring their own laptops, preferably with R already installed (technical assistance will be provided before the workshop to help participants in installing R if necessary). The workshop will be mostly Windows users oriented. The illustrative data set will also be available for participants. Useful references and links: 1) The R software website: http://www.r-project.org 2) The Use R! series of Springer books in general, and more precisely: Zuur, A. F., Ieno, E. N., & Meesters, E. H. W. G. (2009). A beginner’s guide to R. New York: Springer. [less ▲]

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See detailModèles polytomiques issus de la théorie de la réponse à l’item
Raîche, Gilles; Béland, Sébastien; Magis, David ULg

Conference (2013, May 06)

Les items qui composent les échelles de mesure en éducation et en sciences humaines sont fréquemment associées à plus de deux choix de réponses. Il s'agit alors d'items à réponses polytomiques. Plusieurs ... [more ▼]

Les items qui composent les échelles de mesure en éducation et en sciences humaines sont fréquemment associées à plus de deux choix de réponses. Il s'agit alors d'items à réponses polytomiques. Plusieurs modélisations issues de la théorie de la réponse à l'item ont été proposées pour calibrer de telles échelles de mesures. Lorsque les choix de réponses ne sont pas ordonnés, les modèles à réponses nominales peuvent être utilisés. Lorsque ces choix sont ordonnés, les modèles gradués, à crédit partiel ou à appréciation peuvent être appliqués. Cette communication a pour objectif de présenter ces différentes modélisations et d'identifier des solutions logicielles pour effectuer la calibration. La présentation sera effectuée à l'aide d'un exemple auquel les différentes modélisations seront appliquées. Il sera ainsi possible de comparer les paramètres d'items et de personnes obtenus à l'aide de chacune des modélisations retenues. [less ▲]

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See detailApplication of lasso penalization to differential item functioning detection
Magis, David ULg

Scientific conference (2013, February 26)

Identification of differential item functioning (DIF) in dichotomously scored items is often performed item by item. This approach increases the risk of false discovery errors (Type I error rate) as all ... [more ▼]

Identification of differential item functioning (DIF) in dichotomously scored items is often performed item by item. This approach increases the risk of false discovery errors (Type I error rate) as all items other than the tested one are assumed to be free of DIF. Some ad-hoc procedures, such as item purification and alpha level adjustment for multiple comparisons, have been studied in this context. The purpose of this talk is to focus on a different approach based on penalized likelihood estimation of a look-alike IRT model. Specifically, a Rasch model is being introduced with item-group interaction terms (i.e. DIF effects). Rather than obtaining pointwise estimates of the interaction parameters, which may be impossible because of high collinearity effects, the DIF effects are estimated with a lasso penalty term. Several criteria for optimally selecting the lasso tuning parameter are discussed, including cross-validation, AIC, BIC, and variants of these criteria. Preliminary results of a simulation study are presented and discussed. [less ▲]

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See detailRandom generation of dichotomous CAT response patterns with the R package catR
Magis, David ULg

Conference (2013, February 14)

The purpose of this talk is to briefly introduce the R package catR that permits random generation of response patterns under a computerized adaptive testing (CAT) framework. First, an outline of the CAT ... [more ▼]

The purpose of this talk is to briefly introduce the R package catR that permits random generation of response patterns under a computerized adaptive testing (CAT) framework. First, an outline of the CAT is proposed, with emphasis on the main concepts (item bank, ability estimation, next item selection, stopping rule, item exposure and content balancing). Then, the performance of the catR package is described by making connections between the general CAT framework and the functionalities of the R functions within catR. An example will be displayed, either as a “live” demonstration of catR or as part of the talk. Potential extensions of catR will also be discussed. The catR package was jointly developed by Gilles Raîche (Université du Québec à Montréal, Canada). [less ▲]

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See detailAn overview of statistical methods to assess differential item functioning and differential test functioning
Magis, David ULg; Monseur, Christian ULg

Scientific conference (2013, February 12)

This talk broadly focuses on the identification of differential item functioning (DIF) and differential test functioning (DTF). After a short introduction of the key concepts, most-known methods to detect ... [more ▼]

This talk broadly focuses on the identification of differential item functioning (DIF) and differential test functioning (DTF). After a short introduction of the key concepts, most-known methods to detect DIF and DTF with dichotomously or polytomously scored items, and between two or more than two groups, are presented. Both parametric (i.e. IRT) and nonparametric (i.e. score-based) methods are described in a non-technical way. Several potential applications to PISA surveys are discussed. [less ▲]

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See detailEstimation des paramètres d’item et de sujet à partir du modèle de Rasch : une étude comparative des logiciels BILOG-MG, ICL et R
Béland, Sébastien; Magis, David ULg; Raîche, Gilles

in Mesure et Evaluation en Education [=MEE] (2013), 36((1)), 83-110

La théorie de la réponse aux items (TRI) est une classe de modèles de mesure très utilisée en éducation. À ce jour, de nombreux logiciels, tel BILOG-MG, sont disponibles afin de procéder à l'estimation ... [more ▼]

La théorie de la réponse aux items (TRI) est une classe de modèles de mesure très utilisée en éducation. À ce jour, de nombreux logiciels, tel BILOG-MG, sont disponibles afin de procéder à l'estimation des paramètres d'item et de sujet. Parmi ces logiciels, il ne faut pas négliger ICL et R, qui sont gratuits et qui peuvent permettre de produire des analyses diversifiées. Cette étude a pour objectif de comparer la qualité d’estimation des paramètres selon une des modélisations issues de la TRI : le modèle de Rasch. Pour ce faire, nous comparons les estimateurs du paramètre de difficulté et de sujet selon trois logiciels : BILOG-MG, ICL et la librairie ltm disponible dans le logiciel R. Nous procédons à une analyse par simulation informatique et, dans un second temps, nous analysons un test de classement en anglais, langue seconde. Les résultats démontrent que les logiciels étudiés permettent d’obtenir des estimateurs des paramètres similaires, la différence principale entre ces logiciels étant leur temps d’exécution des procédures d’estimation. [less ▲]

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See detailUn processus itératif pour réduire l’impact de réponses aberrantes sur l’identification de patrons de réponses inappropriés
Magis, David ULg; Béland, Sébastien; Raîche, Gilles

in Mesure et Evaluation en Education [=MEE] (2013), 36(2), 87-110

La présence de réponses aberrantes est habituellement détectée par l’utilisation d’indices d’ajustement permettant de déterminer si le patron de réponses est inapproprié par rapport aux caractéristiques ... [more ▼]

La présence de réponses aberrantes est habituellement détectée par l’utilisation d’indices d’ajustement permettant de déterminer si le patron de réponses est inapproprié par rapport aux caractéristiques du test. Cette approche nécessite cependant une pré-estimation des paramètres d’items qui est souvent réalisée sur le même ensemble de données. La présence de réponses aberrantes pourrait donc influencer le processus de calibration et la détection de patrons inappropriés. Cet article présente un processus itératif pour réduire le risque d’une calibration biaisée causée par la présence de réponses aberrantes. La démarche consiste à retirer successivement les patrons identifiés comme inappropriés du processus de calibration des items. Ce processus est illustré en analysant les données d’un test de classement en anglais langue seconde (TCALS-II), au Québec. L’application du processus itératif aux données met en évidence une augmentation du nombre de patrons de réponses détectés comme inappropriés, présentant un impact relativement faible sur les paramètres d’items estimés et un nombre restreint d’itérations nécessaires pour obtenir une convergence du processus itératif. [less ▲]

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See detailA note on the item information function of the four-parameter logistic model
Magis, David ULg

in Applied Psychological Measurement (2013), 37

This paper focuses on four-parameter logistic (4PL) model (Barton & Lord, 1981) as an extension of the usual three-parameter logistic (3PL) model with an upper asymptote possibly different from one. For a ... [more ▼]

This paper focuses on four-parameter logistic (4PL) model (Barton & Lord, 1981) as an extension of the usual three-parameter logistic (3PL) model with an upper asymptote possibly different from one. For a given item with fixed item parameters, Lord (1980) derived the value of the latent ability level that maximizes the item information function under the 3PL model. The purpose of this paper is to extend this result to the 4PL model. A generic and algebraic method is developed for that purpose. The result is practically illustrated by an example and several potential applications of this result are outlined. [less ▲]

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See detailÉvaluation d’un test de lecture en anglais par deux méthodes de détection du fonctionnement différentiel d’items
Pichette, François; Raîche, Gilles; Béland, Sébastien et al

in Revue des Sciences de l'Education (2013), 37

Cette étude vise à examiner la présence de fonctionnement différentiel d’items selon le sexe des répondants dans un test de compréhension en lecture en anglais administré à 171 universitaires francophones ... [more ▼]

Cette étude vise à examiner la présence de fonctionnement différentiel d’items selon le sexe des répondants dans un test de compréhension en lecture en anglais administré à 171 universitaires francophones. Deux méthodes non paramétriques sont utilisées: le test Mantel-Haenszel et le modèle de régression logistique. Sur un total de 64 items, deux présentent un fonctionnement différentiel selon le test Mantel-Haenszel, alors que cinq items supplémentaires ressortent par la régression logistique. Ce faible nombre d’items suggère une bonne équité du test, mais les différences observées soulignent la nécessité d’analyses additionnelles pour clarifier le statut de ces items. [less ▲]

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See detailItem purification does not always improve DIF detection: a counter-example with Angoff’s Delta plot
Magis, David ULg; Facon, Bruno

in Educational & Psychological Measurement (2013), 73

Item purification is an iterative process that is often advocated as improving the identification of items affected by differential item functioning (DIF). With test-score based DIF detection methods ... [more ▼]

Item purification is an iterative process that is often advocated as improving the identification of items affected by differential item functioning (DIF). With test-score based DIF detection methods, item purification iteratively removes the items currently flagged as DIF from the test scores in order to get purified sets of items, unaffected by DIF. The purpose of this paper is to highlight that item purification is not always useful and that a single run of the DIF method may return equally suitable results. Angoff’s Delta plot is considered as a counter-example DIF method, with a recent improvement to the derivation of the classification threshold. Several possible item purification processes may be defined with this method, and all of them are compared through a simulation study and a real data set analysis. It appears that none of these purification processes clearly improves the Delta plot performance. A tentative explanation is drawn from the conceptual difference between the modified Delta plot and the other traditional DIF methods. [less ▲]

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See detailNon-graphical solutions to Cattell's scree test
Raîche, Gilles; Walls, Ted; Magis, David ULg et al

in Methodology: European Journal of Research Methods for the Behavioral and Social Sciences (2013), 9

Most of the strategies that have been proposed to determine the number of components that account for the most variation in a principal components analysis of a correlation matrix rely on the analysis of ... [more ▼]

Most of the strategies that have been proposed to determine the number of components that account for the most variation in a principal components analysis of a correlation matrix rely on the analysis of the eigenvalues and on numerical solutions. The Cattell’s scree test is a graphical strategy with a nonnumerical solution to determine the number of components to retain. Like Kaiser’s rule, this test is one of the most frequently used strategies for determining the number of components to retain. However, the graphical nature of the scree test does not definitively establish the number of components to retain. To circumvent this issue, some numerical solutions are proposed, one in the spirit of Cattell’s work and dealing with the scree part of the eigenvalues plot, and one focusing on the elbow part of this plot. A simulation study compares the efficiency of these solutions to those of other previously proposed methods. Extensions to factor analysis are possible and may be particularly useful with many low-dimensional components. [less ▲]

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See detailImpact de la méthode d'estimation du niveau d'habileté et du choix des premiers items sur l'efficacité de l'administration adaptative du TCALS II
Magis, David ULg; Raîche, Gilles

in Raîche, Gilles; Ndinga, Pascal; Meunier, Hélène (Eds.) Des mécanismes pour assurer la validité de l'interprétation de la mesure en éducation. Tome 3: : aspects pratiques (2013)

Le TCALS II (test de classement en anglais, langue seconde, au collégial, 2e version) est un questionnaire constitué d’un nombre fixe de 85 items administré aux étudiants de la province du Québec qui ... [more ▼]

Le TCALS II (test de classement en anglais, langue seconde, au collégial, 2e version) est un questionnaire constitué d’un nombre fixe de 85 items administré aux étudiants de la province du Québec qui entament des études au niveau collégial. Une version adaptative informatisée de ce test est envisagée pour la première fois dans cette étude. Deux problématiques sont regardées de plus près : le choix d’une méthode d’estimation du niveau d’habileté optimale et la sélection des premiers items du test. Ces deux problématiques sont étudiées simultanément par le biais de simulation Monte-Carlo à partir de plusieurs règles d’arrêt liées à la longueur du test. On en conclut que le choix des premiers items affecte peu l’estimation du niveau d’habileté, tandis que des différences notoires apparaissent toutefois entre les quatre méthodes d’estimation comparées. Certaines conclusions et recommandations sont dressées pour la poursuite ultérieure de ces travaux. [less ▲]

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See detailDuration perception: A Developmental Semiology from 2:6 to 13 Years, General Population versus Atypical, Assessment by Parental Questionnaire
SCHOLL, Jean-Marc ULg; Philippe, Paule; Gérard, Paul ULg et al

Conference (2012, December 20)

Introduction Perception of duration has a major impact on the child’s ability to manage everyday life. Usually, the perception of time is considered in its sequential component. To our knowledge, possible ... [more ▼]

Introduction Perception of duration has a major impact on the child’s ability to manage everyday life. Usually, the perception of time is considered in its sequential component. To our knowledge, possible semiological markers for the capacity to apprehend temporal duration have not yet been explored. There are thus no existing tools either for its evaluation (in everyday life) or for the description of its development during childhood. We are thus largely in the dark about how the perception of duration develops during childhood. Hypothesis 1) It is possible to track perception of duration using semiological markers in everyday life; 2) Children with developmental disorders can be expected to develop difficulties in this domain. Method We designed a questionnaire for parents using a Likert scale. The questionnaire was administered to 2 samples from 2:6 to 13 years: 827 in a general population and 297 in a mixed-psychopathological population recruited from the Mental Health Services network. We carried out a multinomial logistic regression and used percentiles curves (P5,50,95). Results In the general population, perception of duration is gradually acquired and full competence is attained by 9 years. The apprehension of sequential time is achieved by 4 years. In the psychopathological sample, mean perception of temporal duration is delayed by 18 months and significant difficulties remain even at 13 years. The apprehension of sequential time is also delayed: even at 13 years it remains low (at percentile 95). We have found no sex-related differences. Discussion Perception of duration is an important developmental feature which has not been taken into account until now. Semiological markers can be used to differentiate typically developing children from clinical populations as to their respective capacities to perceive temporal duration. [less ▲]

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