Scores estimated from multidimensional item response theory (IRT) models are not necessarily comparable across dimensions. In this article, the concept of aligned dimensions is formalized in the context of Rasch models, and two methods are described--delta dimensional alignment (DDA) and logistic regression alignment (LRA)--to transform estimated…

The aim of the research presented here is the use of extensions of longitudinal item response theory (IRT) models in the analysis and comparison of group-specific growth in large-scale assessments of educational outcomes. A general discrete latent variable model was used to specify and compare two types of multidimensional item-response-theory…

Our objective is to provide two multidimensional models (i.e., contextual-interaction and Ethnic Educator) including sociopolitical, socioeconomic, sociocultural, and sociohistorical factors explaining underachievement in Latinos. First, we critically discuss single-factor theories (i.e., deficit, resistance, social reproduction, cultural…

This study linked nonlinear profile analysis (NPA) of dichotomous responses with an existing family of item response theory models and generalized latent variable models (GLVM). The NPA method offers several benefits over previous internal profile analysis methods: (a) NPA is estimated with maximum likelihood in a GLVM framework rather than…

Multidimensional scaling (MDS) and exploratory and confirmatory factor analyses were compared in the assessment of the dimensionality of data sets, using sets generated to be one-dimensional or two-dimensional and differing in degree of interdimensional correlation and number of items defining a dimension. (SLD)

Examination of a test's internal structure can be used to identify what domains or dimensions are being measured, identify relationships between the dimensions, provide evidence for hypothesized multidimensionality and test score interpretations, and identify construct-irrelevant variance. The purpose of this research is to provide a…

The difference between compensatory and non-compensatory item response theory (IRT) models in terms of the dimensionality of test data generated by them, and its effect on the model-data-fit were examined. The STRESS (proportion of variance not accounted for by the multidimensional scaling model) and RSQ (proportion of variance accounted for by…

The following seven statistical procedures are compared in terms of the ability to recover a unidimensional latent trait from Likert-type data: (1) factor analysis based on Pearson correlations (FA-PR); (2) factor analysis based on polychoric correlations (FA-PL); (3) the graded response model in item response theory (IRT-GRM); (4) internal…

Equatings were performed on both simulated and real data sets using common-examinee design and two abilities for each examinee. Results indicate that effective equating, as measured by comparability of true scores, is possible with the techniques used in this study. However, the stability of the ability estimates proved unsatisfactory. (TJH)

A procedure for interpreting multiple-discrimination indices from a multidimensional item-response theory analysis is described and demonstrated with responses of 1,635 high school students to a multiple-choice test. The procedure consists of converting discrimination parameter estimates to direction cosines and analyzing the angular distances…