12. A method for determining recommendation data, comprising: extracting a first set of keywords from a set of user action logs that occurred prior to a predetermined time point and determining a weight value for at least one of the first set of keywords; extracting a second set of keywords from a set of user action logs that occurred subsequent to the predetermined time point and determining a weight value for at least one of the second set of keywords; merging at least a portion of the first set of keywords and at least a portion of the second set of keywords to obtain a third set of keywords and determining a weight value for at least one of the third set of keywords; matching the third set of keywords to a database of data that can potentially be recommended to a user; and in the event that a piece of data is determined to match at least one keyword from the third set of keywords, determining that the piece of data is to be recommended to the user.
18. The method of claim 12 , wherein merging at least a portion of the first set of keywords and at least a portion of the second set of keywords includes: identifying a duplicate keyword of the third set of keywords that is found in both the first set of keywords and the second set of keywords; and determining a combined weight value for the identified duplicate keyword based at least in part on a weight value of the duplicate keyword determined for the first set of keywords and a weight value of the duplicate keyword determined for the second set of keywords.