28. A method performed by one or more devices, the method comprising: determining, by one or more processors of the one or more devices, an amount that a rank of a document changes over time; determining or adjusting, by one or more processors of the one or more devices, a score for the document based on the amount that the rank of the document changes over time; and ranking, by one or more processors of the one or more devices, the document with regard to at least one other document based on the score.
28. A method performed by one or more devices, the method comprising: determining, by one or more processors of the one or more devices, an amount that a rank of a document changes over time; determining or adjusting, by one or more processors of the one or more devices, a score for the document based on the amount that the rank of the document changes over time; and ranking, by one or more processors of the one or more devices, the document with regard to at least one other document based on the score. 33. The method of claim 28 , where determining the score includes determining the score without generating a relevancy score that is based on a relevance of the document to a search query.