Many scholars compared various item discrimination indices in real or simulated data. Item discrimination indices, such as item-total correlation, item-rest correlation, and IRT item discrimination parameter, provide information about individual differences among all participants. However, there are tests that aim to select a very limited number…

Purpose: Working memory and linguistic knowledge are highly intertwined in language tasks. Verbal working memory in particular has been studied as a potential constraint on language performance. This, in turn, highlights the need for a clinical assessment tool that will assist clinicians in understanding individual children's performance in…

Research has found that the "a"-stratified item selection strategy (STR) for computerized adaptive tests (CATs) may lead to insufficient use of high a items at later stages of the tests and thus to reduced measurement precision. A refined approach, unequal item selection across strata (USTR), effectively improves test precision over the…