On a Shortened Method of Estimation of Mental Factors by Regression
Walter Ledermann · Psychometrika · 1939
A shortened method of finding the regression for estimation of the scores on mental factors is presented. If the correlations among n tests are accounted for by r factors, the regression equation involves the inverse of an r × r matrix instead of the inverse of an n × n matrix. When r is much less than n , there is considerable saving in computational labor. A numerical example is presented to illustrate the method.