1. A system, comprising a processor configured to: execute a document-oriented search based on a query in an index of documents to generate a set of document results, each document associated with at least one potential expert; analyze the document results to produce a list of potential experts; calculate an expertise score for each potential expert based on a content score and a metadata score for each potential expert; calculate a confidence score for each potential expert based on a diversity-constrained content score and a diversity-constrained metadata score for each potential expert, the diversity-constrained content score and the diversity-constrained metadata score to be calculated using an evidence diversity score for each potential expert; and send a list of experts with associated confidence scores that are above a confidence score threshold to a client device.