29. The system of claim 21 , wherein the first number is a total number of long clicks on the search result when the search result was provided in response to the search query, and wherein the second number is a total number of clicks on the search result when the search result was provided in response to the search query.
29. The system of claim 21 , wherein the first number is a total number of long clicks on the search result when the search result was provided in response to the search query, and wherein the second number is a total number of clicks on the search result when the search result was provided in response to the search query. 30. The system of claim 29 , wherein the operations further comprise: classifying the viewing length into a viewing time category of a plurality of viewing time categories; and determining the weight based at least in part on the viewing time category.