A Factor Analytically Derived Classification System for Psychological Reports

Abstract

A sample of approximately 1,000 abstracts was obtained from Psychological Abstracts and keypunched for computer processing. Based upon a frequency distribution of words in these abstracts, 150 tag-terms were selected. These terms were intercorrelated on the basis of their co-occurrence in documents, and the resulting matrix was factor analyzed. The factors were interpreted as representing classification categories. These were compared with, and shown to be similar to, the APA classification system. The study demonstrates that it is possible to determine the basic dimensions of a collection of documents by an analysis of the words used in their abstracts.