Dimensionality of Raven's Advanced Progressive Matrices Items

Raven's Advanced Progressive Matrices (APM) was designed as a nonverbal measure of "Spearman's g" and it is frequently used as the best or only measure of intelligence in current research. As Spearman believed g to be unidimensional, the items comprising the test should define a single factor. Two independent samples of Navy recruits (N = 874 and N = 857) were employed. The data indicated that only a single factor solution was warranted in both samples. A number of technical issues are discussed concerning item factor analysis.