The goal of the present study was to address the analytical complexity of incorporating responses and response times through applying the Jeon and De Boeck mixture item response theory model in Mplus 8.7. Using both simulated and real data, we attempt to identify subgroups of responders that are rapid guessers or engage knowledge retrieval…

Relative difficulty of Separate (Form S) and Grouped (Form G) True-False tests may be expected to be dependent on the ability levels of examinees. At some levels Form S should be less difficult, at others equally difficult, and at still others, more difficult, than Form G. (Author/RL)

No significant differences in performance on a self-adapted test or anxiety were found for college students (n=218) taking a self-adapted test who selected item difficulty without any prior information, inspected an item before selecting, or answered a typical item and received performance feedback. (SLD)