1. A method comprising a computer system implementing a testing interface that allows testing of a loss in variety of a set of results returned by a specific search query, wherein implementing the testing interface comprises the steps of: identifying a set of one or more terms related to the specific search query; wherein the set of one or more terms are not part of the specific search query; obtaining a plurality of search results for the specific search query; determining a first number of results of the plurality of search results; determining a second number of results for each term of the set of one or more terms related to the specific search query, wherein the second number is the number of results that contain said each term; determining, for said each term, 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 first ratio of said third number to the running total; determining a second ratio of the second number to the first number; determining a relevance of the set of results; wherein the set of results includes the plurality of search results, and wherein determining the relevance of the set of results is based at least in part on: (a) said second ratio, for one or more related terms, of the second number to the first number; and (b) said first ratio, for one or more related terms, of said third number to the running total.
1. A method comprising a computer system implementing a testing interface that allows testing of a loss in variety of a set of results returned by a specific search query, wherein implementing the testing interface comprises the steps of: identifying a set of one or more terms related to the specific search query; wherein the set of one or more terms are not part of the specific search query; obtaining a plurality of search results for the specific search query; determining a first number of results of the plurality of search results; determining a second number of results for each term of the set of one or more terms related to the specific search query, wherein the second number is the number of results that contain said each term; determining, for said each term, 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 first ratio of said third number to the running total; determining a second ratio of the second number to the first number; determining a relevance of the set of results; wherein the set of results includes the plurality of search results, and wherein determining the relevance of the set of results is based at least in part on: (a) said second ratio, for one or more related terms, of the second number to the first number; and (b) said first ratio, for one or more related terms, of said third number to the running total. 9. The method of claim 1 , further comprising: determining that none of the results in the set of results contain a particular term from the set of one or more terms; and determining, based at least in part on the ratio of said third number of the particular term to the running total, the loss in variety for the set of results.