Collaborative Memory Network for Recommendation Systems

Travis Ebesu
Bin Shen
Yi Fang
SIGIR2018(2018) (to appear)
Google Scholar

Abstract

Recommendation systems play a vital role to keep users engaged with personalized content in modern online platforms. Deep learning has revolutionized many research fields and collaborative filtering (CF) is no different. However, existing methods compose deep learning architectures with the latent factor model ignoring a major class of CF models, neighborhood or memory-based approaches. We propose Collaborative Memory Networks (CMN), a deep architecture to unify the two classes of CF models capitalizing on the strengths of the global structure of latent factor model and local neighborhood-based structure in a nonlinear fashion. Motivated by the success of Memory Networks, we fuse a memory component and neural attention mechanism as the neighborhood component. The associative addressing scheme with the user and item memories in the memory module encodes complex user-item relations coupled with the neural attention mechanism to learn a user-item specific neighborhood. Finally, the output module jointly exploits the neighborhood with the user and item memories to produce the final ranking score. Stacking multiple memory modules together yielding deeper architectures capturing additional complex useritem relations. Furthermore, we show strong connections between CMN components and two classes of CF models. Comprehensive experimental results demonstrate the effectiveness of CMN on two public datasets outperforming competitive baselines. Qualitative visualization of the attention weights provide insight into the model’s recommendation process and suggest the presence of higher order interactions.