Ramsay curve item response theory (RC-IRT) was recently developed to detect and correct for nonnormal latent variables when unidimensional IRT models are fitted to data using maximum marginal likelihood estimation. The purpose of this research is to evaluate the performance of RC-IRT for Likert-type item responses with varying test lengths, sample…

The early stage of computerized adaptive testing (CAT) refers to the phase of the trait estimation during the administration of only a few items. This phase can be characterized by bias and instability of estimation. In this study, an item selection criterion is introduced in an attempt to lessen this instability: the D-optimality criterion. A…

Content balancing is an important issue in the design and implementation of computerized adaptive testing (CAT). Content-balancing techniques that have been applied in fixed content balancing, where the number of items from each content area is fixed, include constrained CAT (CCAT), the modified multinomial model (MMM), modified constrained CAT…

This study compares the performance of three nonparametric item characteristic curve (ICC) estimation procedures: isotonic regression, smoothed isotonic regression, and kernel smoothing. Smoothed isotonic regression, employed along with an appropriate kernel function, provides better estimates and also satisfies the assumption of strict…

The authors propose a concise formula to evaluate the standard error of the estimated latent variable score when the true values of the structural parameters are not known and must be estimated. The formula can be applied to factor scores in factor analysis or ability parameters in item response theory, without bootstrap or Markov chain Monte…

Seven papers on technical and practical issues in equating are presented. Problems related to the use of conventional and item response theory equating methods, using pre- and post-smoothing to increase equipercentile equating's precision, and linear equating models for common-item nonequivalent-population design are discussed. (SLD)

Dorans and Holland (2000) and von Davier, Holland, and Thayer (2003) introduced measures of the degree to which an observed-score equating function is sensitive to the population on which it is computed. This article extends the findings of Dorans and Holland and of von Davier et al. to item response theory (IRT) true-score equating methods that…

This study investigates whether the functions linking number-correct scores to the College-Level Examination Program (CLEP) scaled scores remain invariant over gender groups, using test data on the 16 testlet-based forms of the CLEP College Algebra exam. To be consistent with the operational practice, linking of various test forms to a common…

Several approaches to reporting subscale scores can be found in the literature. This research explores a multidimensional compensatory dichotomous and polytomous item response theory modeling approach for subscale score proficiency estimation, leading toward a more diagnostic solution. It also develops and explores the recovery of a Markov chain…

Conditions under which interaction effects estimated from classical total scores, rather than item response theory trait scores, can be misleading are discussed with reference to analysis of variance (ANOVA). When no interaction effects exist on the true latent variable, spurious interaction effects can be observed from the total score scale. (SLD)

A meta-theoretical framework that begins with the standard system of measurement is outlined. Identification of different standard systems and elements of the measurement process provide a focus for comparisons between measurement theories and models. (SLD)

When tests are made up of testlets, a testlet-based item response theory (IRT) model may be used to account for local dependence among items from a common testlet. This study presents a new test characteristic curve method to link calibrations based on the Bradlow, Wainer, and Wang (1999) testlet model. Procedures for calculating the test…

Recent work has shown that multidimensionally scoring responses from different tests can provide better ability estimates. For educational assessment data, applications of this approach have been limited to binary scores. Of the different variants, the de la Torre and Patz model is considered more general because implementing the scoring procedure…

Psychometric theory focuses primarily on tests that are homogeneous, measuring only one attribute of a psychosocial entity. However, the complexity of psychosocial behavior often requires tests that are heterogeneous, measuring more than one attribute. In this presentation, reliability and internal consistency are extended to heterogeneous tests…

This Monte Carlo study compares the ability of the parametric bootstrap version of DIMTEST with three goodness-of-fit tests calculated from a fitted NOHARM model to detect violations of the assumption of unidimensionality in testing data. The effectiveness of the procedures was evaluated for different numbers of items, numbers of examinees,…