All guilds in all servers Server: S1 N=766861000 (a) (b) N=24033 kinship model 100200 200 1o108 6100 s Server: S2 Server: S3 1000 N=24477 N=28176 100k200 200 ∧ u口日 0o10 100 250 s 10 WoW Empirical data (blue)& Team-formation Modeling Results(red) Cumulative guild size distribution and Churn vs guild size N from data is taken as input (data in oct 2005WoW Empirical data (blue) & Team-formation Modeling Results (red) Cumulative guild size distribution and Churn vs guild size N from data is taken as input (data in Oct 2005) N=76686 N=24033 N=24477 N=28176