SIMPLE STRUCTURE AND THE NUMBER OF FACTORS PROBLEM

If the varimax criterion values. for rotations of successively greater numbers of principal axes of the image covariance matrix G are listed, they may be examined for two features: the unimodality of the distribution reflects the clarity of latent structure; and the peak value indicates the number of common factors present. The procedure is applied to nine published example problems and compared to other rules of thumb for determining the rank of a factor matrix.