Validity Measures in the Context of Latent Trait Models

摘要

In contrast to the progressive desolution of the reliability coefficient inclassical mental test theory and the replacement by the test information function in latent trait models, the issue of test validity has been more or less neglected in modern mental test theory. The present paper proposes some considerations about the validity of a test and of a single item. Effort has been focused upon searching for measures which are population-free, and which will provide us with local and abundant information just as the information functions do in comparison with the test reliability coefficient in classical mental test theory. In so doing, validity indices for different purposes of testing and also those which are tailored for a specific population of examinees are considered. (rh)