This study examined whether the item response curves from a two-parameter model reflected characteristics of the mathematics items, each of which required unique cognitive tasks. A computer program performed error analysis of test performance. Cognitive subtasks appeared to influence the slopes and difficulties of item response curves. (GDC)

Although multivariate generalizability theory was developed more than 30 years ago, little published research utilizing this framework exists and most of what does exist examines tests built from tables of specifications. In this context, it is assumed that the universe scores from levels of the fixed multivariate facet will be correlated, but the…