Evolution Analysis of a Mobile Social Network

Smart phones and ubiquitous wireless connections are helping people to build and maintain mobile social relationships. We present an in-depth and complete evolution analysis on the user activities and social graph of a mobile social network using data obtained from Nokia Friend View. Our results show that (1) user activities in Friend View are highly correlated and the power law fitted exponents for user activities distribution are slowly becoming larger over time, which appears to be contrary to the famous “rich get richer” assertion in the preferential attachment model because users in Friend View regard the reciprocity as important during the interaction and (2) both undirected friend network and directed comment network in Friend View are small-world and scale-free networks over time with slowly decreasing clustering coefficient. However, compared to online social networks where users have a large number of friends but loose weakly-tied subgroups, users in Friend View tend to have close strongly-tied cohesive subgroups. The results can help us understand users’ social activities and interactions over time in mobile social networks.