1. A computer-implemented method for developing a profile of a user including topic clusters, the method comprising: storing, by a computer, a plurality of topic clusters, the plurality of topic clusters including a set of related topics; retrieving a profile of a user, the profile including a plurality of topics indicating interests of the user; identifying, from the plurality of topic clusters, a topic cluster including a topic from the plurality of topics included in the profile of the user; adding the identified topic cluster to a list of topic clusters for the profile of the user; identifying a plurality of users, each of the plurality of users associated with a profile that includes the identified topic cluster added to the list of topic clusters for the profile of the user; identifying a plurality of videos interacted with by the plurality of users; selecting a video from the plurality of videos to recommend to the user based on interactions of the plurality of users with the plurality of videos; and recommending the selected video to the user.
1. A computer-implemented method for developing a profile of a user including topic clusters, the method comprising: storing, by a computer, a plurality of topic clusters, the plurality of topic clusters including a set of related topics; retrieving a profile of a user, the profile including a plurality of topics indicating interests of the user; identifying, from the plurality of topic clusters, a topic cluster including a topic from the plurality of topics included in the profile of the user; adding the identified topic cluster to a list of topic clusters for the profile of the user; identifying a plurality of users, each of the plurality of users associated with a profile that includes the identified topic cluster added to the list of topic clusters for the profile of the user; identifying a plurality of videos interacted with by the plurality of users; selecting a video from the plurality of videos to recommend to the user based on interactions of the plurality of users with the plurality of videos; and recommending the selected video to the user. 2. The method of claim 1 , further comprising: generating the plurality of topic clusters based on a co-occurrence matrix, the co-occurrence matrix storing co-occurrence strengths for pairs of topics.