The Subject-Item Interaction in Itemmetric Research

Abstract

In their investigation of the relationship between item properties and test quality, itemmetricians rely too heavily upon inference about the nature of the subject-item interaction. Itemmetric research can be improved by employing data, specifying variables, and selecting an order of data analysis which are more directly related to this interaction. Some predicted relationships among certain item characteristics, response processes, instability of response, and nearness of subject and item on a trait continuum are used to compare the traditional and proposed approaches. Stronger relationships and clearer interpretations arise from the proposed approach.