Information communities: The network structure of communication

This project gives a general definition of communities in the context of communication networks, an important and well-studied category of social networks. Our work mathematically justifies the claim that sparse network ties, as opposed to tightly structured solidarity groups, can form a foundation for locating social communities. We develop and test a model of communities based on a novel set of assumptions. Empirical tests in two sets of communication networks show that this model is more useful for identifying groups of individuals that have strong internal relationships in closed networks than those defined by more general models of network closure. These findings extend the scope of network closure effects proposed by other researchers working with communication networks.