Item response theory (IRT) refers to a family of mathematical models which describe the relationship between latent continuous variables (attributes or characteristics) and their manifestations (dichotomous/polytomous observed outcomes or responses) with regard to a set of item characteristics. Researchers typically use parametric IRT (PIRT)…

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

This comprehensive "Handbook" focuses on the most used polytomous item response theory (IRT) models. These models help us understand the interaction between examinees and test questions where the questions have various response categories. The book reviews all of the major models and includes discussions about how and where the models…

Comments are made on the review papers presented by six Dutch psychometricians: Ivo Molenaar, Wim van der Linden, Ed Roskam, Arnold Van den Wollenberg, Gideon Mellenbergh, and Dato de Gruijter. Molenaar has embraced a pragmatic viewpoint on Bayesian methods, using both empirical and pure approaches to solve educational research problems. Molenaar…

The purpose of this paper is to present a generalization of the concept of item difficulty to test items that measure more than one dimension. Three common definitions of item difficulty were considered: the proportion of correct responses for a group of individuals; the probability of a correct response to an item for a specific person; and the…

Significant to a latent trait or item response theory analysis of a mental test is the determination of exactly what is being quantified. The following are practical problems to be considered in the formulation of a good theory: (1) deciding whether two tests measure the same trait or traits; (2) analyzing the relative contributions of a pair of…

The nonparametric approach to test theory discussed here has its roots in the early work of Guttman, Lazarsfeld, and Meredith; and more recently in the work of Cliff and in Tatsuoka and Tatsuoka. Mokken's extensive treatment of this subject concentrated on defining, constructing, and testing unidimensional scales, based on responses to dichotomous…

To assess the effects of correlated abilities on test characteristics, and to explore the effects of correlated abilities on the use of a multidimensional item response theory model which does not explicitly account for such a correlation, two tests were constructed. One had two relatively unidimensional subsets of items, the other had all…

The purpose of this book is to make it possible for measurement specialists to solve practical testing problems through the use of item response theory (IRT). The topics, organization, and presentation are those used in a 4-week seminar held each summer for the past several years. The material is organized to facilitate understanding; all related…

The fit between individuals and their work environments has received decades of theoretical and empirical attention. This study investigated two antecedents to individuals' perceptions of fit: vocational interests and personality. More specifically, the authors hypothesized that vocational interests assessed in terms of the Career Occupational…

This study used classical psychometric, latent trait, and nonparametric approaches to analyze 13- and 14-item scales of English language proficiency. Tests of English listening comprehension (dictation) and reading ("copytest") were constructed by modifying the standard dictation testing procedure to create items of text segments which…

This research program was designed to investigate the applications of item response theory and computerized adaptive testing to the unique problems of the measurement of ability and the measurement of achievement. The research utilized a combination of monte carlo simulation studies and live-testing studies. The research approach for adaptive…

Studies carried out over a 12-year period addressed fundamental questions on the use of Rasch-based item banks. Large field tests administered in grades 3-8 of reading, mathematics, and science items, as well as standardized test results were used to explore the possible effects of many factors on item calibrations. In general, the results…

This paper presents an introduction to the use of latent trait models for the estimation of domain scores. It was shown that these models provided an advantage over classical test theory and binomial error models in that unbiased estimates of true domain scores could be obtained even when items were not randomly selected from a universe of items.…

Uses principles of latent trait theory to derive conditions under which mean differences between groups on an observed variable are in fact indicative of mean differences on an underlying construct. Pays particular attention to the logistic curve as a model for describing the relation between the observed variable and the construct. (Author/CB)