Biographical Sketches.

The article presents information on researchers. It is reported that Elizabeth Alfert received her PhD in psychology at the University of California at Berkeley and has been a research psychologist in the Berkeley Department of Psychiatry of the Student Health Service. She is presently associated with the Wright Institute, Berkeley. It is informed that Henry A. Alker is assistant professor in psychology, sociology, and the Graduate Faculty of Government at Cornell University. He received his BA (in philosophy) from Oberlin, did graduate work at Oxford and received his PhD at Berkeley in personality psychology. Following a postdoctoral fellowship at Educational Testing Service at Princeton, he went to Cornell where he teaches personality and political psychology. It is reported that Stephen L. Burbeck holds a research appointment at California State University, Long Beach, the institution from which he received his BA in 1969. Trained in mathematics, he is presently Senior Programmer with the Urban Disorder Project at Long Beach, developing mathematical models of collective behavior.