13. The system of claim 12 , the plurality of components further comprising a query metadata determiner component that assigns the query category to the query based upon the document category being assigned to an item in the items previously retrieved by the search engine based upon the query.
12. A system that facilitates ranking items returned by a search engine in response to receipt of a query, the system comprising: a processor; and a memory that comprises a plurality of components that are executed by the processor, the plurality of components comprising: a receiver component that receives a document category previously assigned to a first item and a query category previously assigned to the query; a computation component that computes a document-query feature for a combination of the first item and the query, the document-query feature computed based upon the document category and the query category, the document-query feature indicative of whether the document category matches the query category, the query category previously assigned to the query based upon document categories assigned to items previously retrieved by the search engine based upon the query; and a ranker component that receives the items returned by the search engine and outputs a ranked list of items based upon the query, a position of the first item in the ranked list of items based upon the document-query feature.