Abstract
Centrality is an important element of social network analysis (SNA) measuring the relative power and influence of members of a social network. In face book-style online social networks every member is potentially able to communicate with everyone else within the network. This has an important impact on centrality: the power derivable from (exclusive) connections within the social graph is reduced because network members must not necessarily follow links. In this paper we propose a new measure for centrality which reflects this paradigm shift. It is based not on connectedness but on trust. We discuss different notions of trust, introduce trust matrix and trust centrality and provide an algorithm for its calculation.