15. The system of claim 13 , wherein the computing device is further caused to merge the click distance values with other statistics before ranking the search results.
15. The system of claim 13 , wherein the computing device is further caused to merge the click distance values with other statistics before ranking the search results. 16. The system of claim 15 , wherein a scoring function is populated with the computed click distance values and the other ranking values for producing a score by which the documents are ranked.