1. A method, comprising: obtaining search history data, the search history data including a first query; determining whether a different second query is temporally related to the first query based on calculated time-based query-to-query transition probabilities including a query-to-time transition probability between the first query and a time of year and a time-to-query transition probability between the time of year and the second query, where the query-to-time transition probability between the first query and the time of year estimates a strength of a relationship between the first query and the time of year, wherein determining the query-to-time transition probability comprises: determining whether the first query has a significant increase in popularity at the time of year; and if the first query does have a significant increase in popularity at the time of year, determining the query-to-time transition probability as a function of the number of times the query had a significant increase in popularity at the time of year; and modifying, using one or more computers, scoring data for one or more documents responsive to the second query to favor newer documents responsive to the second query based on the calculated time-based query-to-query transition probabilities.