ABSTRACT
If the majority of factorial studies making use of ratings have come from England, nearly all the questionnaire, inventory, and other self-rating studies have come from America. This fact has given rise to differences in the treatment of data which may at first appear confusing to the reader. As pointed out before, the London school, in their analysis of ratings, have followed, by and large, the principle of extracting the most comprehensive factors first and of keeping factors orthogonal; the Americans have rather followed the principle of extracting smaller “group” or “primary” factors first and letting these factors be intercorrelated. It is from the intercorrelations of these primary factors that they then proceed to extract the broader, more general factors which the English school would have extracted right at the beginning. As has been mentioned before the two procedures do not involve any fundamental difference in the final outcome of the analysis provided they are both carried out competently by workers who are clearly aware of the difficulties and fallacies involved. However, sometimes the analysis is not carried to a proper conclusion—a member of the London school may only extract the most important one or two factors; the follower of Thurstone may not complete his analysis by extracting second-order factors—and in that case there may be a superficial contrast between the two methods of analysis which may appear to give substance to the view held by some psychologists, namely that factor analysts agree with each other as little as do psychoanalysts.
