This study tested the hypothesis that measured aptitudes and self-ratings of these same aptitudes reflect a common domain of psychometric behavior. Male and female applicants for vocational guidance completed a self-rating scale and then the General Aptitude Test Battery (GATB). The self-rating scale contained six vocational/educational aptitudes. These were general intelligence, verbal, numerical, spatial, form perception, and clerical aptitudes. A seven point rating scale of very high to very low was included for each aptitude. Components analyses were carried out on each six by correlation matrix and canonical correlation analysis was used to identify maximal relationships between weighted linear components of self-rated and tested aptitudes. Two separate components analyses revealed the major proportion of variance can be accounted for by one factor on which all the scales loaded highly. The high degree of congruence between the first two components in the unrotated analyses was revealed by Tucker coefficients of 0.992 and 0.794. The size of the maximum canonical correlation (0.58) indicated some overlap between self-ratings and test scores. (Author/DWH)