1. An apparatus comprising: one or more computer processing units configured to execute instructions associated with a plurality of modules, the modules comprising: a visibility module configured to derive a hit visibility score for one or more hits from an information source, wherein the one or more hits result from one or more searches directed to a target entity and include information about the target entity, and wherein the hit visibility score indicates a likelihood that a corresponding hit is found by a searcher after the searcher searches for the target entity in the information source; a sentiment module configured to derive a hit sentiment score for at least one of the one or more hits, wherein the hit sentiment score indicates a sentiment about the target entity conveyed by the at least one of the one or more hits; and a reputation module configured to derive a reputation for the target entity based on the hit visibility score and the hit sentiment score; and a data storage configured to store the one or more hits.