Ramsey, Philip H.2011-01-282011-01-281978Ramsey, Philip H. (1978). Factor analysis of the WAIS and twenty French-kit reference tests. Applied Psychological Measurement, 2, 505-517. doi:10.1177/014662167800200405doi:10.1177/014662167800200405https://hdl.handle.net/11299/99444Over a 3-year period, 20 reference tests were given to 114 undergraduate students ranging in age from 18 to 46. The WAIS was given to 107 of the students. Maximum likelihood factor analysis was performed on the 31-variable correlation matrix formed by the 11 WAIS subscales and 20 reference tests. A maximum likelihood test of significance supported the hypothesis of 10 factors. Significant split-sample factor reliabilities and WAIS subscale loadings were found on all 10 factors. The rotated factors in order of explained variance were Verbal Comprehension, Visualization, Memory Span, Syllogistic Reasoning, General Reasoning, Induction, Mechanical Knowledge, Number Facility, Spatial Orientation, and Associative Memory. The apparent contradictions between many previous analyses of the WAIS are discussed and a unified interpretation is presented.enArticle