ABSTRACT
In an early paper, Arabie (1977) made a distinction between explicit and implicit overlap in sociological data. The former approach can be further subdivided into research (a) that welcomes (and even seeks out) overlap versus (b) that which seeks to eliminate or diminish its presence. Perhaps the best known example of the "welcome" attitude toward overlap is in the study of corporate interlock (e.g., Levine, 1972; Subcommittee on Reports, Accounting and Management of the Committee on Government Affairs, United States Senate, 1978), where it is the actors who overlap on the boards of different corporations who are the focus of the data analyses. This substantive problem is subsumed in the more general framework for
studying formal patterns of overlap in interorganizational networks of shared resources (Galaskiewicz and Marsden, 1978; Laumann, Galaskiewicz, and Marsden, 1978; Galaskiewicz and Wasserman, 1981; Knoke and Wood, 1981). Concern for overlap has also emerged sporadically in discussions of such other social processes as diffusion (Dodd and Winthrop, 1953, p. 191).
