1. A computer-implemented method, comprising: maintaining, by a social networking system, a plurality of personas describing entities represented in the social networking system, each persona associated with a page provided by the social networking system; determining a plurality of persona clusters, each persona cluster including a set of the plurality of personas that purport to be the same entity based on content in the page associated with each persona; and for each of one or more of the persona clusters: identifying interactions of the personas in the cluster with a plurality of entities, determining a measure of authenticity for each persona of the persona cluster, the measure of authenticity comprising a weighted aggregate of the identified interactions with the plurality of entities, wherein an interaction initiated by an entity and received by the persona is weighted higher than an interaction initiated by the persona and received by the entity, the measure of authenticity further weighing each interaction based on a measure of authenticity of the entity interacting with the persona, and selecting an authentic persona of the plurality of personas in the persona cluster based on the determined measures of authenticity; and storing information describing a selected authentic persona for each persona cluster.