This study examined the effect of similar vs. dissimilar proficiency distributions on uniform DIF detection on a statewide eighth grade mathematics assessment. Results from the similar- and dissimilar-ability reference groups with an SWD focal group were compared for four models: logistic regression, hierarchical generalized linear model (HGLM),…

This study examines the use of cross-classified random effects models (CCrem) and cross-classified multiple membership random effects models (CCMMrem) to model rater bias and estimate teacher effectiveness. Effect estimates are compared using CTT versus item response theory (IRT) scaling methods and three models (i.e., conventional multilevel…

Teacher and school accountability systems based on high-stakes tests are ubiquitous throughout the United States and appear to be growing as a catalyst for reform. As a result, educators have increased the proportion of instructional time devoted to test preparation. Although guidelines for what constitutes appropriate and inappropriate test…