In this article we derive implications about social positions from a formal theory of social influence. The formal theory describes how, in a group of actors with heterogeneous initial opinions, a network of interpersonal influences enters into the formation of actors' settled opinions. We derive the following conclusions about a special form of structural equivalence. If actors are structurally equivalent in the network of interpersonal influences, then any dissimilarity of their initial opinions is reduced by the social influence process. If the social positions of actors are identical, i.e. if they have identical initial opinions and are structurally equivalent in the influence network, then they have identical opinions at equilibrium. If actors are not structurally equivalent in the network of interpersonal influences, then the social influence process does not necessarily reduce dissimilarities of initial opinions. We extend our analysis to consider automorphic equivalence.

Williamson's (1971) model of control loss in organizational hierarchies describes the cumulative decay of influence of superiors over subordinates who are separated by a number of hierarchical levels in the chain-of-command. This paper shows that control loss may be deduced from a network theory of social influence, and it shows that ties among actors at the same hierarchical level-Fayol's gangplanks-may constrain control loss in organizational hierarchies. The structural mitigation of control loss by Fayol's gangplanks increases with superiors' span of control and depends on their capacity to maintain influence upon immediate subordinates in the presence of the lateral influences among subordinates. © 2002 Elsevier Science B.V. All rights reserved.

This note addresses the historical antecedents of the 1998 PageRank measure of centrality. An identity relation links it to the 1990-1991 models of Friedkin and Johnsen. © 2014 Elsevier B.V.

In this paper we describe an approach to the relationship between a network of interpersonal influences and the content of individuals' opinions. Our work starts with the specification of social process rather than social equilibrium. Several models of social influence that have appeared in the literature are derived as special cases of the approach. Some implications for theories on social conflict and conformity also are developed in this paper. © 1990, Taylor & Francis Group, LLC. All rights reserved.