This study investigated the dimensionality of mathematics subscale scores from the National Assessment of Educational Progress for the assessment's Technical Review Panel, specifically for the data from the 1990 and 1992 main assessment in relation to students' instructional and noninstructional background variables. Discriminant analysis was…

A live tailored achievement testing study was conducted to compare procedures based on the one- and three-parameter logistic models. Previous studies yielded inconclusive results because of the procedures by which item calibrations were linked and because of the item selection procedures. Using improved procedures, 83 college students were tested…