A social networking system determines whether a user is a real public figure or is the correct “public persona” of an individual who is famous within a particular domain. The system selects one or more trusted agents. A trusted agent is a user who has been confirmed or is otherwise trusted within the system. The system traverses the social graph of the trusted agent to score and identify additional users who have a sufficient connection to the trusted agent to authenticate them as other confirmed public personas/figures. The system computes confidence scores of the connections of the trusted agent, considering the strength of the connections and other relevant factors. The system provides confidence scores for one or more target users in the social network based on the confidence scores of the friends or connections connecting the trusted agent and the target user.