Item position effect (IPE) refers to situations where an item performs differently when it is administered in different positions on a test. The majority of previous research studies have focused on investigating IPE under linear testing. There is a lack of IPE research under adaptive testing. In addition, the existence of IPE might violate Item…

The focus of this paper is on the empirical relationship between item difficulty and item discrimination. Two studies--an empirical investigation and a simulation study--were conducted to examine the association between item difficulty and item discrimination under classical test theory and item response theory (IRT), and the effects of the…

This study employs the 4-parameter logistic item response theory model to account for the unexpected incorrect responses or slipping effects observed in a large-scale Algebra 1 End-of-Course assessment, including several innovative item formats. It investigates whether modeling the misfit at the upper asymptote has any practical impact on the…