14. The computing device of claim 11 , wherein the index is a search engine index that is accessible at time of receiving the search request.
14. The computing device of claim 11 , wherein the index is a search engine index that is accessible at time of receiving the search request. 15. The computing device of claim 14 , wherein the first ranking score is based at least in part on information that cannot be computed in response to the search request due to computation time that is longer than a predetermined threshold.