Application of statistical methods to mental test data

摘要: The papers of which this thesis is composed are mainly concerned with the application of statistical methods to certain problems of mental testing. Educational psychologists have on the whole been rather slow to make use of modern statistical technique, and factorial analysts in particular appear to have overlooked any consideration of the efficiency of the methods which they have employed in factor estimation. In the first paper the method of maximum likelihood was therefore applied to the problem of estimating factor loadings, and equations were obtained which, when solved, gave efficient estimates cf these quantities. In addition a criterion was found for deciding, in large samples, how many factors could be regarded as statistically significant.