19. A system, comprising: a memory device to store computer-executable instructions; and one or more processors, to execute the computer-executable instructions, to: determine an amount or rate that a document moves positions in search result rankings over time; generate a score for the document based on the amount or rate that the document moves in the search result rankings over time; and rank the document with regard to at least one other document based on the score.
25. The system of claim 19 , where the score is a first score, where the one or more processors are further to: determine a set of search terms relating to a particular topic or news item; determine that the document is associated with the set of search terms; identify another document that is not associated with the set of search terms; generate a second score for the other document, where the first score is higher than the second score; and rank the document with regard to at least the other document based on the first and second scores.