Cognitive diagnostic models can uncover students' mastery of multiple fine-grained skill attributes or problem-solving processes. A number of studies have applied cognitive diagnostic models to detect students' knowledge mastery in mathematics and language testing. However, few studies focus on cognitive diagnostic assessment in K-12 science…

In cognitive diagnosis assessment (CDA), the impact of misspecified item-attribute relations (or "Q-matrix") designed by subject-matter experts has been a great challenge to real-world applications. This study examined parameter estimation of the CDA with the expert-designed Q-matrix and two refined Q-matrices for international…

This dissertation aims to investigate the effect size measures of differential item functioning (DIF) detection in the context of cognitive diagnostic models (CDMs). A variety of DIF detection techniques have been developed in the context of CDMs. However, most of the DIF detection procedures focus on the null hypothesis significance test. Few…