It has long been the desire of administrators, particularly those concerned with personnel selection problems, to find an objective method of dividing people into types. So far, the accepted method of obtaining data to achieve this object has been to submit the individuals to some form of testing procedure. Although the objective type of test, scored quite independently of the opinion of the marker, has done much to dispense with criticisms against the examination system, the interpretation of the results is obviously of little value unless it is known precisely what the tests are measuring. It is, for instance, obvious that the score in a test, ostensibly of mathematical ability, in general depends to some extent on the ability of the candidate to read, and, in fact, all tests probably measure several aspects of attainment. For this reason it is evidently desirable that some method should be found of separating test scores into components which can be ascribed to specific attainments, and the process of doing this is called Factor Analysis.