Exploratory factor analysis (EFA) is generally regarded as a technique for large sample sizes ("N"), with N = 50 as a reasonable absolute minimum. This study offers a comprehensive overview of the conditions in which EFA can yield good quality results for "N" below 50. Simulations were carried out to estimate the minimum required "N" for different…

New research suggests that personalities prone to extreme violence can be predicted by analysis of chemical elements found in human hair. Methodology employed and results obtained are highlighted and discussed. Relationships between diet and human behavior are also discussed. (JN)

This overview of the field of personality theory evaluates the important features of Raymond Cattell's work. While there are many areas of agreement between Cattell and other personality theorists, his rejection of traditional clinical methods for measurement and experimentation has created controversy as well as an extraordinarily rich…

In this overview of his research in personality theory, Cattell describes the play of people, situations, and, ideas enacted over 30 years in his University of Illinois laboratory. Establishing meaningful empirical measurement methods was the foundation for further research into many aspects of personality development. (BS)