A note on factor analysis by the method of principal axes

The resolution of a set of variables into principal components may be performed upon variables having arbitrary variances, or upon variables obtained from these by reduction of all variances to unity. The two procedures do not yield the same results even if the principal components are reduced to unit variance in both cases, except when the original variances are all equal.This article was written while the author was on a W.P.A. project at Teacher's College, Columbia University.