6. The method of claim 1 , wherein the step of updating the first weight comprises updating the first weight based on a distribution of determined feature types across N queries, where N>1.
6. The method of claim 1 , wherein the step of updating the first weight comprises updating the first weight based on a distribution of determined feature types across N queries, where N>1. 7. The method of claim 6 , wherein the updated weight is based on a ratio among current weights and a ratio among the distribution of determined feature types across the N queries.