Many researchers have suggested that the main cause of item bias is the misspecification of the latent ability space. That is, items that measure multiple abilities are scored as though they are measuring a single ability. If two different groups of examinees have different underlying multidimensional ability distributions and the test items are…

Three frequently used response formats are compared via analysis of covariance structures. The cumulative results based on four data sets provided evidence inconsistent with previous research suggesting that these formats are interchangeable. The semantic-differential format is most preferred while in most cases the Stapel format is least…

A general process for testing the feasibility of applying alternative mathematical or statistical models to the solution of a practical problem is presented and flowcharted. The system is used to develop a plan to compare models for test equating. The five alternative models to be considered for equating are: (1) anchor test equating using…

A two-dimensional, compensatory item response model and a unidimensional model were fitted to the reading and mathematics items in the Woodcock-Johnson Psycho-Educational Battery-Revised for a sample of 1,000 adults aged 20-39 years. Multidimensional information theory predicts that if the unidimensional abilities can be represented as vectors in…

Item response data were obtained from large samples of students in Grades K-community college, taking the following tests: Stanford Early School Achievement Test, Stanford Achievement Test, Stanford Test of Academic Skills, Stanford Diagnostic Reading Test, and Stanford Diagnostic Mathematical Test. Data were classified as fitting or non-fitting…

This material provides a discussion of the construction and analysis of tests prepared for classroom use by teachers. The initial discussion is concerned with the purposes of evaluation and the specification of objectives. This is followed by an examination of theoretical and practical considerations in planning a test. The material on test item…