Abstract: This application relates to a system and methods including allowing an annotation to an electronic document, optionally inputting the annotated electronic document to a recommendation engine, processing the annotated electronic document, querying a data source with at least one of the annotated electronic document and a result of the processing, and presenting at least one recommended electronic document or no recommended electronic documents based on a result of the query. Related user interfaces, applications, and computer program products are disclosed.

Abstract: A novel system and method of predicting a user's rating of a new item in a collaborative filtering system is described. The invention incorporates social network information in addition to user ratings to make recommendations. The distance between users in the social network is used to enhance the estimate of user similarities for collaborative filtering. The social network can be constructed explicitly by users or deduced implicitly from observed interaction between users.