Asked and Answered : Communication Patterns of Experts on an Online Forum

The notion of network structure for social relations dates back half a century. Nowadays people form social networks offline as well as online. At an online community people are connected trough information exchange of sorts. Interest groups form often forums to aid each other and discuss things. Programmers are no exception and a question and answer site called Stack Overflow has been up and running since 2008. Our focus is to find patterns of how people interact on this online community and see if we can find expert users. We find 4 different ways to categorize experts, which result in different rankings. We also investigate how expertise is divided among topics, and find some overlap with the global ranking.