9. The method of claim 3 , wherein said determining values for the coefficients of the relevance function that substantially minimize a sum over a set of queries of the defined query error comprises: initializing the one or more coefficients; calculating a sum of query errors based on the defined query error for a plurality of queries; calculating a gradient of the calculated sum of the query errors; and modifying the one or more coefficients in a negative direction of the calculated gradient.
9. The method of claim 3 , wherein said determining values for the coefficients of the relevance function that substantially minimize a sum over a set of queries of the defined query error comprises: initializing the one or more coefficients; calculating a sum of query errors based on the defined query error for a plurality of queries; calculating a gradient of the calculated sum of the query errors; and modifying the one or more coefficients in a negative direction of the calculated gradient. 11. The method of claim 9 , wherein said calculating a sum of query errors based on the defined query error for a plurality of queries comprises: calculating a regularized sum of query errors based on the defined query error for a plurality of queries.