How community structure influences epidemic spread in social networks

Two key features of social networks are the community structure and the high clustering coefficient. For understanding their influences on dynamical processes, we present a model with both an adjustable clustering coefficient and an adjustable degree of community. This model has an invariant degree distribution when its clustering coefficient is being adjusted. We find that the efficiency of epidemic spreading in this model depends mainly on the degree of community and decreases with increase of the degree of community. For a fixed degree of community, the efficiency will decrease with increase of the clustering coefficient. Numerical simulations have confirmed the theoretic analysis.