Two Steps to Obfuscation

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

Counting hard-to-count populations: the network scale-up method for public health

Estimating sizes of hidden or hard-to-reach populations is an important problem in public health. For example, estimates of the sizes of populations at highest risk for HIV and AIDS are needed for designing, evaluating and allocating funding for treatment and prevention programmes. A promising approach to size estimation, relatively new to public health, is the network scale-up method (NSUM), involving two steps: estimating the personal network size of the members of a random sample of a total population and, with this information, estimating the number of members of a hidden subpopulation of the total population. We describe the method, including two approaches to estimating personal network sizes (summation and known population). We discuss the strengths and weaknesses of each approach and provide examples of international applications of the NSUM in public health. We conclude with recommendations for future research and evaluation

Combinatorial structures in loops

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46265/1/209_2005_Article_BF01221880.pd

Combinatorial structures in loops, III. Difference sets in special cyclic neofields

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/21876/1/0000282.pd

Social influence and opinions

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

Control loss and Fayol’s gangplanks

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

Social positions in influence networks

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