A Model of Robust Positions in Social Networks

What makes an actor's position in social structure robust rather than fragile? This article introduces a network model that pictures occupants of robust positions as recipients of diversified support from durably located others, and portrays occupants of fragile positions as dependents on tenuously situated others. The model builds from Herfindahl's measure of concentration and Bonacich's (1987) measure of status. Using Newcomb's panel study of status-conferring flows among members of a college fraternity, we find empirical support for the contention that fragility reduces future growth in status. Extensions of the model both to input-output networks among industries in the U.S. economy and to hiring networks among academic departments are presented. Implications for future research are discussed