IN a previous paper (4), two of the present authors reviewed current trends in the development of various psychometric techniques which may be designated collectively as pattern analysis. The purpose of the present report is to describe the application of one such method to an empirical study of ability test materials.Of comparatively recent vintage, pattern analytic procedures are based on the assumption that psychological test scores and test responses can be more fruitfully interpreted if account is taken of the relationships existing among them. The evidence previously reviewed (4) supports the contention that more penetrating quantitative descriptions can be obtained by studying the manner in which measured traits (viz., test scores) and attributes (viz., test responses) are associated in and by the individual.