Patent ID: 8869042

Claim:
A method of recommending content to a user of a preference system comprising one or more processors, the method comprising: receiving, from users of the preference system, preference events for a plurality of content items presented to the users; for each content item in the plurality of content items, tracking a number of positive preference events received for the content item; and operating the one or more processors to recommend content items for a first user by: based on the received preference events, determining correlations between the first user and other users of the preference system by, for each of the other users: calculating a first sum of: a first number of content items for which both the first user and the other user initiated preference events of a first type; and a second number of content items for which both the first user and the other user initiated preference events of a second type; calculating a second sum of: a first total number of preference events of the first type and the second type initiated by the first user; and a second total number of preference events of the first type and the second type initiated by the other user; and calculating the quotient of the first sum divided by the second sum; identifying a set of multiple users having greater than a threshold correlation with the first user; and identifying content items for which positive preference events were received from the set of users.