Mixture Rasch (MixRasch) models conventionally assume normal distributions for latent ability. Previous research has shown that the assumption of normality is often unmet in educational and psychological measurement. When normality is assumed, asymmetry in the actual latent ability distribution has been shown to result in extraction of spurious…

In this article, the authors applied profile analysis to Maths exam data to demonstrate how different exam forms, differing in difficulty and length, can be reported and easily interpreted. The results were presented for different groups of participants and for different institutions in different Maths domains by evaluating the balance. Some…

Mixture item response theory (IRT) models have been suggested as an efficient method of detecting the different response patterns derived from latent classes when developing a test. In testing situations, multiple latent traits measured by a battery of tests can exhibit a higher-order structure, and mixtures of latent classes may occur on…

The effects of extended time on the writing performance of university students with learning disabilities (LD) was examined. Thirty-eight students (19 LD; 19 non-LD) completed a collection of cognitive, linguistic, and literacy measures, and wrote essays under regular and extended time conditions. Limited evidence was found to support the…

This simulation study compared the performances (Type I error and power) of Mantel-Haenszel (MH), SIBTEST, and item response theory-likelihood ratio (IRT-LR) methods under certain conditions. Manipulated factors were sample size, ability differences between groups, test length, the percentage of differential item functioning (DIF), and underlying…

Problem Statement: Computerized adaptive testing (CAT) is a sophisticated and efficient way of delivering examinations. In CAT, items for each examinee are selected from an item bank based on the examinee's responses to the items. In this way, the difficulty level of the test is adjusted based on the examinee's ability level. Instead of…

We assessed whether and how the discourse written for prototype integrated tasks (involving writing in response to print or audio source texts) field tested for the new TOEFL® differs from the discourse written for independent essays (i.e., the TOEFL essay). We selected 216 compositions written for 6 tasks by 36 examinees in a field…

The Netherlands' secondary education system is highly differentiated, with four different school types for four scholastic ability levels. Final examinations must accommodate these four levels, and require a test-independent definition of the intended final ability levels as well as a sample-free evaluation of the range of ability levels at which…