CLUSTER-BASED SCALABLE COLLABORATIVE FILTERING

Methods for determining a predictive rating are disclosed. In an embodiment, an active user is compared to a set of clusters. One or more of the clusters are determined to be most similar to the active user. From the one or more clusters, K users are determined to be most similar to the active user. Prior ratings for an item by the K users may be used to predict a rating for the item for the active user.