Patent ID: 8468155

Claim:
A computer-implemented method comprising: choosing item recommendations for a plurality of users comprising at least a first user and a second user; and outputting the item recommendations; wherein choosing item recommendations for a plurality of users comprises: for the first user, identifying, out of a plurality of possible user similarity measures, a first user similarity measure as most accurately identifying users who provided rating information similar to rating information provided by the first user; for the first user, using the first user similarity measure to identify, from the plurality of users, a first set of similar users who provided rating information similar to the rating information provided by the first user; for the first user, using the rating information provided by the first set of similar users to select a first item recommendation; for the second user, identifying, out of the plurality of possible user similarity measures, a second user similarity measure as most accurately identifying users who provided rating information similar to rating information provided by the second user, wherein the second user similarity measure is different than the first user similarity measure; for the second user, using the second user similarity measure to identify, from the plurality of users, a second set of similar users who provided rating information similar to the rating information provided by the second user; and for the second user, using the rating information provided by the second set of similar users to select a second item recommendation.