Four-parameter models have received increasing psychometric attention in recent years, as a reduced upper asymptote for item characteristic curves can be appealing for measurement applications such as adaptive testing and person-fit assessment. However, applications can be challenging due to the large number of parameters in the model. In this…

Much has been written concerning the potential group differences in responding to multiple-choice achievement test items. This discussion has included references to possible disparities in tendency to omit such test items. When test scores are used for high-stakes decision making, even small differences in scores and rankings that arise from male…