Allowing Users to Weight Search Terms in Information Retrieval

We give a principled method for allowing users to assign subjective weights to the importance of search terms, that is, the terms forming a query, in information retrieval systems. For example, our method makes it possible for a user to say that she cares twice as much about the rst search term as the second search term, and to obtain a ranked list of results that reeects this preference. Our method is based upon a simple formula derived from any existing \unweighted" ranking function. A naive application of the weighted formula would require issuing as many distinct queries as there are search terms, thus damaging the response time of the retrieval. We explain here how to \smoothly" integrate the formula in most retrieval engines, so as not to aaect the retrieval performance in terms of response time.