3. The method of claim 1 , further comprising: delivering the search results, by the search engine, to a web graph, wherein the web graph contains a plurality of interlinked web documents each represented by a node (u 1 , u 2 , . . . u n ), and is stored on one or more computers coupled with the search engine; and retrieving, by the search engine, values of one or more operators based on the relative linking within the web graph between the one or more organic search results, the plurality of sponsored search results, and any of the plurality of web documents, each of which corresponds to a node in the web graph.
3. The method of claim 1 , further comprising: delivering the search results, by the search engine, to a web graph, wherein the web graph contains a plurality of interlinked web documents each represented by a node (u 1 , u 2 , . . . u n ), and is stored on one or more computers coupled with the search engine; and retrieving, by the search engine, values of one or more operators based on the relative linking within the web graph between the one or more organic search results, the plurality of sponsored search results, and any of the plurality of web documents, each of which corresponds to a node in the web graph. 5. The method of claim 3 , wherein the operator comprises Reachable Vertices, which is a function, f(u 1 ,u 2 ), that provides a number of web documents that link to both web documents u 1 and u 2 through at least one other web document, but no more than a predetermined maximum number of nodes.