The SIOC Ontology can be used to express information from the online community sites in a machine-readable form using RDF. This rich data structure allows us to easily analyse and extract social relations from these community sites. We use SIOC information to analyse the social relations between users through the content that they create. We introduce metrics for social neighbourhood and social reputation, formally expressed as SPARQL queries over SIOC data. Finally, we demonstrate these algorithms in our Social SIOC Explorer prototype.