When Collaborative Filtering Meets Reinforcement Learning

Yu Lei; Wenjie Li

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arXiv · 1902.00715

When Collaborative Filtering Meets Reinforcement Learning

Yu Lei·Wenjie Li

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Abstract

In this paper, we study a multi-step interactive recommendation problem, where the item recommended at current step may affect the quality of future recommendations. To address the problem, we develop a novel and effective approach, named CFRL, which seamlessly integrates the ideas of both collaborative filtering (CF) and reinforcement learning (RL). More specifically, we first model the recommender-user interactive recommendation problem as an agent-environment RL task, which is mathematically described by a Markov decision process (MDP). Further, to achieve collaborative recommendations for the entire user community, we propose a novel CF-based MDP by encoding the states of all users into a shared latent vector space. Finally, we propose an effective Q-network learning method to learn the agent's optimal policy based on the CF-based MDP. The capability of CFRL is demonstrated by comparing its performance against a variety of existing methods on real-world datasets.

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BibTeX RIS

Yu Lei, Wenjie Li. 2019-04-02. When Collaborative Filtering Meets Reinforcement Learning. https://arxiv.org/abs/1902.00715

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