Multilevel data structures are ubiquitous in the assessment of differential item functioning (DIF), particularly in large-scale testing programs. There are a handful of DIF procures for researchers to select from that appropriately account for multilevel data structures. However, little, if any, work has been completed to extend a popular DIF…

Recent trends in the analysis of categorical or nominal variables were discussed for univariate, multivariate, and psychometric problems. It was shown that several statistical procedures commonly used with these problems have analogues which can be applied to assessing categorical variables. (Author/CTM)

This study (1) provided evidence concerning the construct validity of scales based on the clusters found in a revised, professional-level form of the California Occupational Preference System Interest Inventory and (2) examined the degree of internal consistency of the 16 newly devised subscales. (Author/PN)