Many multiple aptitude test batteries, including the Air Force Officer Qualifying Test (AFOQT), used for assigning or classifying individuals to jobs or for occupational counseling have subtests covering a broad range of content such as science, mathematics, reading, vocabulary, perceptual, mechanical, or technical knowledge. This content reflects a belief that performance in different jobs is best predicted by subtests whose content appears to be closely related to jobs. It has been demonstrated that the subtests of a multiple aptitude test battery all measure, in large part, an examinee's general learning ability, often called psychometric g, in addition to the specific abilities implied by the differing contents of the subtests. This study investigated methods for estimating psychometric g from the Air Force Officer Qualifying Test Form O. The methods used and compared were unrotated principal components, unrotated principal factors and variants of hierarchical factor analysis. Subjects were 2,984 applicants to Air Force commissioning programs. Results indicated that the methods produced estimates of g which were equal except for scale with a range of correlations from .980 to .999. This relationship was all predictable from a theorem presented by S. S. Wilks. (Contains 16 references and 12 tables.) (Author)