Multirelational Recommendation in Heterogeneous Networks

Recommender systems are key components in information-seeking contexts where personalization is sought. However, the dominant framework for recommendation is essentially two dimensional, with the interaction between users and items characterized by a single relation. In many cases, such as social networks, users and items are joined in a complex web of relations, not readily reduced to a single value. Recent multirelational approaches to recommendation focus on the direct, proximal relations in which users and items may participate. Our approach uses the framework of complex heterogeneous networks to represent such recommendation problems. We propose the weighted hybrid of low-dimensional recommenders (WHyLDR) recommendation model, which uses extended relations, represented as constrained network paths, to effectively augment direct relations. This model incorporates influences from both distant and proximal connections in the network. The WHyLDR approach raises the problem of the unconstrained proliferation of components, built from ever-extended network paths. We show that although component utility is not strictly monotonic with path length, a measure based on information gain can effectively prune and optimize such hybrids.