10. A method comprising the steps of: a computer identifying a set of one or more terms related to a specific search query; wherein the set of one or more terms are not part of the specific search query; the computer determining, for each term of the set of one or more terms, a third number of historical search queries, and adding said third number to a running total; wherein said third number is based on a count of those historical search queries that include both the specific search query and said each term; determining a ratio of said third number to the running total; the computer obtaining a plurality of search results for the search query; the computer determining that none of the results in the plurality of search results contain a particular term from the set of one or more terms; the computer generating a value representing a loss in variety for a set of results; wherein the set of results includes the plurality of search results, and wherein generating the value representing the loss in variety for the set of results is based at least in part on the ratio of said third number, for each term of the set of one or more terms, to the running total; and the computer reporting the value representing the loss in variety for the set of results.
17. The method of claim 10 , wherein the loss in variety measures a lack of sub-topics found within a set of search results; wherein the sub-topics are associated with a general topic; and wherein the sub-topics are comprised of the set of one or more terms, and the general topic is comprised of the terms in the search query.