This study aimed to evaluate the item model fit by equating the forms of the PISA 2018 mathematics subtest with concurrent common items equating in samples from Türkiye, the UK, and Italy. The answers given in mathematics subtest Forms 2, 8, and 12 were used in this context. Analyzes were performed using the Dichotomous Rasch Model in the WINSTEPS…

A multidimensional Bayesian item response model is proposed for modeling item position effects. The first dimension corresponds to the ability that is to be measured; the second dimension represents a factor that allows for individual differences in item position effects called persistence. This model allows for nonlinear item position effects on…

Testlets have advantages such as making it possible to measure higher-order thinking skills and saving time, which are accepted in the literature. For this reason, they have often been preferred in many implementations from in-class assessments to large-scale assessments. Because of increased usage of testlets, the following questions are…

Many scales contain both positively and negatively worded items. Reverse recoding of negatively worded items might not be enough for them to function as positively worded items do. In this study, we commented on the drawbacks of existing approaches to wording effect in mixed-format scales and used bi-factor item response theory (IRT) models to…

Changing the order of items between alternate test forms to prevent copying and to enhance test security is a common practice in achievement testing. However, these changes in item order may affect item and test characteristics. Several procedures have been proposed for studying these item-order effects. The present study explores the use of…