Diagnostic classification models (DCMs) are psychometric models that can be used to estimate the presence or absence of psychological traits, or proficiency on fine-grained skills. Critical to the use of any psychometric model in practice, including DCMs, is an evaluation of model fit. Traditionally, DCMs have been estimated with maximum…

Psychologists frequently use symptom validity tests (SVTs) to help determine whether evaluees' test performance or reported symptoms accurately represent their true functioning and capability. Most studies evaluating the accuracy of SVTs have used either known-group comparisons or simulation designs, but these approaches have well-known…

This article provides GP-CORE norms for a South African university sample, which are compared to published data obtained from a United Kingdom university sample. The measure appears to be both reliable and valid for this multilingual and multicultural South African sample. The profiles of the psychological distress reported by white South African…

Paul E. Newton's "Clarifying the Consensus Definition of Validity" addresses the single most important, yet stubbornly protean, value in educational and psychological assessment. "Standards for Educational and Psychological Testing" (American Educational Research Association, American Psychological Association, & National Council on Measurement in…

Diagnostic hit rates for the Diagnostic Inventory of Personality and Symptoms were compared to diagnosis by psychiatrists of the same patients. The Probability Scale employing Bayesian concepts and base rates correctly classified 70% of the patients and was more accurate by far than the other two methods used. (Author/ABB)

A numerical procedure is outlined for obtaining an interval estimate of true score. The procedure is applied to several sets of test data. (Author)

The empirical Bayes modeling approach--latent ability random sampling in the item response theory (IRT) context--to the IRT modeling of psychological tests is described. Under the usual empirical Bayes unidimensional IRT modeling approach, the posterior distribution of examinee ability given test response is approximately normal for a long test.…

This report describes new statistical procedures for item response analysis using estimation of item response curves used in mental testing with ability parameters treated as a random sample. Modern computer technology and the EM algorithm make this solution possible. The research focused on the theoretical formulation and solution of maximum…

This paper presents a hierarchical Bayes circumplex model for ordinal ratings data. The circumplex model was proposed to represent the circular ordering of items in psychological testing by imposing inequalities on the correlations of the items. We provide a specification of the circumplex, propose identifying constraints and conjugate priors for…