Obtaining Group Measures from Personality Test Scores: Auto Brand Choice Predicted from the Edwards Personal Preference Schedule

From a single set of data, a method derives measures both of individuals' personalities and of social groups to which they belong. A scatter diagram of psychological test scores, of needs to be friendly and to be dominant, for example, is given a new origin at the median of the distribution. In this group-centered diagram, new axes, at 45° from the originals, divide the population equally into quadrants. A need axis distinguishes where one need is stronger than the other relative to the group. An intensity axis differentiates degree of strength of both needs combined. More auto owners were correctly classified with two need variables than by linear discriminant function with 10 variables. The method treats two measures on an individual in relationship with each other and in relationship to other individuals. This makes possible relating knowledge of individuals' personal systems with knowledge of social systems of groups in which individuals function.