This study utilizes an analysis of diminishing returns to examine the relationship between sample size and item parameter estimation precision when utilizing the Masters' Partial Credit Model for polytomous items. Item data from the standardization of the Batelle Developmental Inventory, 3rd Edition were used. Each item was scored with a…

The University Student Depression Inventory (USDI; Khawaja and Bryden 2006) is a 30- item scale that is used to measure depressive symptoms among university students. Its psychometric properties have been widely investigated under the classical test theory (CTT). This study explored the application of the polytomous Rasch partial credit model…

In this study, the effect of mathematics teacher candidates' locus of control on math anxiety was tested, along with the effects of gender, achievement and class level moderators. The study was carried out according to a causal design in which locus of control was taken as an independent variable, while math anxiety was taken as the dependent…

The present study compared item and ability invariance as well as model-data fit between the one-parameter (1PL) and three-parameter (3PL) Item Response Theory (IRT) models utilizing real data across five grades; second through sixth as well as simulated data at second, fourth and sixth grade. At each grade, the 1PL and 3PL IRT models were run…