Source: Dissertation Abstracts International, Volume: 66-01, Section: A, page: 0155.

A new index based on the conditional covariance of item scores given a latent variable is defined and investigated to assess dimensionality in educational and psychological test data. This index successfully detects the test dimensionality in both identifying the number of dimensions present in...

A new method for estimating the ability parameters in the statistical models based on item response theory (IRT) was presented in this study. A brief review of existing parameter estimation methods suggested the utility of a parameter estimation method which requires no specific assumption. By...

Heterogeneity in measurement model parameters across known groups can be modeled and tested using multigroup confirmatory factor analysis (CFA). When it is not reasonable to assume that parameters are homogeneous for all observations in a manifest group, mixture CFA models are appropriate....

A multidimensional extension of the generalized graded unfolding model for repeated measures (GGUM-RM) is introduced and applied to analyze attitude change across time using responses collected by a Thurstone or Likert questionnaire. The model conceptualizes the change across time as separate...

If data exhibit a dimensional structure more complex than what is assumed, key conditional independence assumptions of the hypothesized model do not hold. The current work pursues posterior predictive model checking, a flexible family of Bayesian model checking procedures, as a tool for...

The cross-validated classification accuracy of predictive discriminant analysis (PDA) and logistic regression (LR) models was compared for the two-group classification problem. Thirty-four real data sets varying in number of cases, number of predictor variables, degree of group separation,...

Tests comprising item bundles, (i.e., groups of items related to common passages, paragraph, or graphs), have been treated as if they measure only a general trait, ignoring the within bundle dependencies. The consequences of not taking into account the specificity of each group of items are, in...

Source: Dissertation Abstracts International, Volume: 59-10, Section: B, page: 5428.

Source: Dissertation Abstracts International, Volume: 69-01, Section: A, page: 0194.