On the statistical treatment of residuals in factor analysis

A method for estimation in factor analysis is presented. The method is based on the assumption that the residual (specific and error) variances are proportional to the reciprocal values of the diagonal elements of the inverted covariance (correlation) matrix. The estimation is performed by a modification of Whittle's least squares technique. The method is independent of the unit of scoring in the tests. Applications are given in the form of nine reanalyses of data of various kinds found in earlier literature.The writer wishes to thank Prof. H. Wold, Dr. E. Lyttkens, and Dr. P. Whittle for valuable comments and suggestions.