Statistics in Psychology and Education (Henry E. G)

THE present day emphasis on measurement and the quantitative treatment of results has made a knowledge of statistical method not only extremely useful but almost necessary to the student of psychology, education, and the social sciences. To those who have been well trained in mathematics, the acquisition of statistical technique offers no particular difficulty. To many otherwise capable students, however, either because of inadequate preparation in mathematics, or because their preparation is not very recent, the application of statistical method to data obtained from test and experiment is more than ordinarily difficult. It is for this last group of students, especially, that this book has been written. Its primary purpose is to present the subject in a simple and concise form understandable to those who have no previous knowledge of statistical method. With this end in view, theory has everywhere been subordinated to practical application, and numerous illustrations of the various statistical devices have been provided. References have been given, however, for the benefit of those interested in the mathematical theory underlying the methods introduced. The reader will note that in nearly all cases formulas have simply been stated without proof. This has been done, because the writer believes that most students of mental and social measurement are-and probably should be-more concerned wish what a formula means and does than in how it is derived. There is considerable justification for such an attitude.’ In every science certain facts obtained from other fields must be taken on faith. We do not, to take a simple example, restrict the use of the radio or the microscope to those who understand the physical principles involved, and there seems to be no real