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…

Many scholars compared various item discrimination indices in real or simulated data. Item discrimination indices, such as item-total correlation, item-rest correlation, and IRT item discrimination parameter, provide information about individual differences among all participants. However, there are tests that aim to select a very limited number…

This article discusses the application of the Golden Rule procedure to items of the Scholastic Aptitude Test. Using item response theory, the analyses indicate that the Golden Rule procedures are ineffective in detecting biased items and may undermine the reliability and validity of tests. (Author/JAZ)