8. A non-transitory computer-readable medium embodying a set of computer-executable instructions, the instructions comprising instructions for: receiving a search query; identifying one or more listings responsive to the search query; determining, for each of the one or more listings, a relevancy score based on one or more parameters in the search query, an expected click through rate, and a content density boost for a listing category that is a ratio of a click-through rate when a particular type of field is included in a listing in the listing category to a click-through rate when the particular type of field is excluded from a listing in the listing category; and calculating, for each of the one or more listings, a performance score based at least in part on the relevancy score, the expected click through rate, and the content density boost.
8. A non-transitory computer-readable medium embodying a set of computer-executable instructions, the instructions comprising instructions for: receiving a search query; identifying one or more listings responsive to the search query; determining, for each of the one or more listings, a relevancy score based on one or more parameters in the search query, an expected click through rate, and a content density boost for a listing category that is a ratio of a click-through rate when a particular type of field is included in a listing in the listing category to a click-through rate when the particular type of field is excluded from a listing in the listing category; and calculating, for each of the one or more listings, a performance score based at least in part on the relevancy score, the expected click through rate, and the content density boost. 13. The non-transitory computer-readable medium of claim 8 , the instructions further comprising instructions for adjusting the content density boost based on at least one of the one or more parameters in the search query.