One of the important underlying assumptions of all item response theory (IRT) models is that of local independence. This assumption requires that the response to an item on a test not be influenced by the response to any other items. This assumption is often taken for granted, with little or no scrutiny of the response process required to answer…

Assessment programs like the American College Test (ACT) and the Scholastic Aptitude Test (SAT) continue to play an important role in the admission decisions of many colleges. In many cases, they also serve a meaningful counseling and guidance function for high schools and colleges. The data reported in this paper suggest that the two programs can…