The Q-matrix played a key role in implementations of diagnostic classification models (DCMs) or cognitive diagnostic models (CDMs) -- a family of psychometric models that are gaining attention in providing diagnostic information on students' mastery of cognitive attributes or skills. Using two Monte Carlo simulation studies, this dissertation…

This study addresses the underexplored terrain of conceptualizing and operationalizing race and ethnicity as grouping variables in Differential Item Functioning (DIF) studies within the context of psychometric research. The investigation extends beyond the identification of DIF and delves into the theoretical framing and communication of findings…

My dissertation research explored responder behaviors (e.g., demonstrating response styles, carelessness, and possessing misconceptions) that compromise psychometric quality and impact the interpretation and use of assessment results. Identifying these behaviors can help researchers understand and minimize their potentially construct-irrelevant…

Despite the increasing demand for diagnostic information, observed subscores have been often reported to lack adequate psychometric qualities such as reliability, distinctiveness, and validity. Therefore, several statistical techniques based on CTT and IRT frameworks have been proposed to improve the quality of subscores. More recently, DCM has…

The emergence of digital-first assessments is prompting reconsideration of, and innovation in, aspects of psychometrics, test validation, and test use. Using the Duolingo English Test (DET) as an example, this three-paper series seeks to address issues concerning the estimation of classification consistency and the reporting of results for such…

Micceri (1989) examined the distributional characteristics of 440 large-sample achievement and psychometric measures. All the distributions were found to be nonnormal at alpha = 0.01. Micceri indicated three factors that might contribute to a non-Gaussian error distribution in the population. The first factor is subpopulations within a target…

Diagnostic classification models (DCMs) are structured latent class models widely discussed in the field of psychometrics. They model subjects' underlying attribute patterns and classify subjects into unobservable groups based on their mastery of attributes required to answer the items correctly. The effective implementation of DCMs depends…

This study leveraged the complementary nature of confirmatory factor (CFA), item response theory (IRT), and latent class (LCA) analyses to strengthen the rigor and sophistication of evaluation of two new measures of the Air Force Academy's "leader of character" definition--the Character Mosaic Virtues (CMV) and the Leadership Mosaic…

Previous "selective" meta-analyses of the literature relating to the IQ-achievement discrepancy model of specific learning disability identification have concluded that "underachieving" and "low-achieving" poor readers do not differ in any educationally meaningful way. Underachievers are those poor readers who qualify as learning disabled using an…