Lewis: An ideal experience is something like the help desk at a library. Depending on your question, the librarian may just need to provide a short direct answer or refer you to the reference or periodicals section. Similarly, a search engine needs to align the relevance strategy for each case. For example, for information found in periodicals, the recency of the news or journal publication is important in determining the relevance for the search engine. But the relevance ranking of search results should not penalize a document entered into the system two years ago when looking for factual information that has not changed. For short answers, specific answers should appear that also hyperlink back into the larger documents.