Analysis of Homophily Effects on Information Diffusion on Social Networks

Homophily is a well-known phenomenon in social networks, which is the tendency for individuals with similar characteristics to connect with each other. However, it is still unclear how homophily affects information diffusion. In this paper, we analyze the effect of homophily on information diffusion dynamics through theoretical analysis and numerical simulations. To this end, we consider the information diffusion process on a modular network consisting of two types of nodes with different diffusion properties: agitators and skeptists. In this setting, homophily is represented as the localization of agitators towards a specific community within a network. The analysis reveals that homophily has a significant effect on information diffusion dynamics. Although community structure (i.e., the connectivity between communities) has little or no effect on prevalence rate and diffusion speed without homophily, it affects them with homophily. Especially in networks with strongly separated communities, homophily facilitates local diffusion and inhibits global diffusion.