Privacy Issues with Sharing and Computing Reputation across Communities

Online communities are the new-age platform for sharing information and experiences with groups of people. Members of a community are dealing with the daily conflict of having to decide what information they are willing to disclose in order to increase their reputation. Fear of possible privacy loss may lead a member to avoid sharing information with others, even when acting anonymously. Privacy concerns are amplified when users are members of multiple communities and their overall reputation is obtained from their reputation in each community. Disclosing a piece of reputation-related information in one community may cause privacy loss in another community and vice versa. This paper outlines the privacy concerns in the Cross-Community Reputation (CCR) model for sharing reputation knowledge across communities. These privacy concerns are discussed and modeled, and a policy-based approach that copes with them is presented.