3 M. Karnstedt T. Hennessy J. Chan C. Hayes 2010 IEEE International Conference on Social Computing (SocialCom2010) <p>Churn has been identified as an important issue in a wide range of industries. In social networks, churn represents a significant risk for the health and functioning of communities. However, the importance and actual meaning of churn in social networks is almost unexplored. This work provides a general view on these issues and discusses aspects that are especially relevant to discussion boards. We provide a broad literature review on &ldquo;traditional&rdquo; churn analysis and prediction and highlight the specialities of churn in social networks. We further present an empirical analysis of a churn definition particularly appropriate for discussion boards and propose future research directions for predicting churn in social networks, focusing on the importance of social roles, influence and influence diffusion.</p> http://www.deri.ie/fileadmin/documents/karn-socialcom2010.pdf