12. The medium of claim 11 , wherein determining that the respective search results determined by the first search engine as satisfying the respective first search queries do not satisfy an informational need comprises determining an absence of a selection of any of the respective search results determined by the first search engine.
12. The medium of claim 11 , wherein determining that the respective search results determined by the first search engine as satisfying the respective first search queries do not satisfy an informational need comprises determining an absence of a selection of any of the respective search results determined by the first search engine. 13. The medium of claim 12 , wherein determining the absence of the selection of any of the respective search results displayed in the user interface comprises detecting an absence of a selection of any of a plurality of identifiers displayed in the user interface, wherein an identifier is included in each search result and references a resource determined by the first search engine as satisfying the first search query.