9. The computer-readable memory device of claim 7 , where the method further comprises: determining that a document, in the set of second documents, is fresh when the document has been updated within a particular period of time relative to a current time; and determining that the document is not fresh when the document has not been updated within the particular period of time.
9. The computer-readable memory device of claim 7 , where the method further comprises: determining that a document, in the set of second documents, is fresh when the document has been updated within a particular period of time relative to a current time; and determining that the document is not fresh when the document has not been updated within the particular period of time. 10. The computer-readable memory device of claim 9 , where the method further comprises: assigning a first freshness score to the first document when a majority of documents, in the set of second documents, are fresh; and assigning a second freshness score to the first document when a majority of documents, in the set of second documents, are not fresh, where the first freshness score is greater than the second freshness score.