Determining the Number of Common Factors in Factor Analysis: A Review and Program

Determining the number of common factors is one of the most important decisions which must be made in the application of factor analysis. Several different approaches and techniques are reviewed here along with associated strengths and weaknesses. It is argued that a combination of approaches will lead to the best judgment regarding the number of factors to retain. A computer program is available which presents the number of factors to retain as suggested by both discontinuity and parallel analyses. Utilization of the program removes the negative aspect associated with the use of each technique.