Notes
The author is indebted to Paul Levitt and Harrison White for extensive critical comments. Support for the present research was obtained through NSF Grant GS‐2689. A more extensive development of the present model is contained in a conference paper presented at the MSSB Advanced Research Symposium on Social Networks held in Hanover, N.H., September 18–21, 1975. This paper is available as Discussion Paper No. 78, Fels Center of Government, University of Pennsylvania.