“How did they know?”—model-checking for analysis of information leakage in social networks

We examine the use of model-checking in the analysis of information leakage in social networks. We take previous work on the formal analysis of digital crowds and show how a variation on the formalism can naturally model the interaction of people and groups of followers in intersecting social networks. We then show how probabilistic models of the forwarding and reposting behaviour of individuals can be used to analyse the risk that information will leak to unwanted parties. We illustrate our approach by analysing several simple examples.