Maintaining equivalent performance standards across forms is a psychometric challenge exacerbated by small samples. In this study, the accuracy of two equating methods (Rasch anchored calibration and nominal weights mean) and four anchor item selection methods were investigated in the context of very small samples (N = 10). Overall, nominal…

A widely used approach for categorizing the level of differential item functioning (DIF) in dichotomous items is the scheme proposed by Educational Testing Service (ETS) based on a transformation of the Mantel-Haeszel common odds ratio. In this article two classification schemes for DIF in polytomous items (referred to as the P1 and P2 schemes)…

Methodological procedures used in validating the theoretical structure of academic self-concept and validating associated measurement instruments are reviewed. Substantive findings from research related to modes of inquiry are summarized, and recommendations for future research are outlined. (TJH)