The difficulties in comparing profile variability (a measure of test scatter) are briefly discussed and the limitations of current techniques pointed out. Test scatter is defined as individual variation in test scores between or within various psychological and educational tests. Currently, no statistical technique for the comparison of profile…

The model for educational measurement developed by George Rasch, a Danish psychometrician, is reviewed and its application to occupational educational testing discussed. The Rasch model is an adaptation from the theory of latent trait analysis. According to it, answering an item correctly is a function of the difficulty of the item and the ability…

Three and one-half years of research on computerized ability testing are summarized. The original objectives of the research were: (1) to develop and implement the stratified computer-based ability test; (2) to compare, on psychometric criteria, the various approaches to computer-based ability testing, including the stratified computerized test,…