Group Formation in Large Social Networks: Membership, Growth, and Evolution Lars Backstrom Dan Huttenlocher Jon Kleinberg Dept. of Computer Science Dept. of Computer Science Dept. of Computer Science Cornell University, Ithaca NY and Johnson Graduate School Cornell University, Ithaca NY of Management
[email protected] Cornell University, Ithaca NY
[email protected] [email protected] Xiangyang Lan Dept. of Computer Science Cornell University, Ithaca NY
[email protected] connected to one another. We use decision-tree techniques to iden- tify the most significant structural determinants of these properties. ABSTRACT We also develop a novel methodology for measuring movement of individuals between communities, and show how such movements The processes by which communities come together, attract new are closely aligned with changes in the topics of interest within the members, and develop over time is a central research issue in the communities. social sciences — political movements, professional organizations, and religious denominations all provide fundamental examples of Categories and Subject Descriptors: H.2.8 Database Manage- such communities. In the digital domain, on-line groups are be- ment: Database Applications – Data Mining coming increasingly prominent due to the growth of community General Terms: Measurement, Theory and social networking sites such as MySpace and LiveJournal. How- Keywords: social networks, on-line communities, diffusion of in- ever, the challenge of collecting and analyzing large-scale time- novations