A Biometrics Invited Paper. A Synthetic Basis for a Comprehensive Factor-Analysis Theory

A review is presented of the post-war development of three theories in factor analysis which together form a basis for further development of methodology of the subject. They are the formulation of the factor-analysis model as a special type of second-order stochastic process, the maximum-likelihood theory of estimation of variables in the factor-analysis model when response variates are normally distributed, and the theory of analytic rotation based on optimization of an objective function.