User-Centric Path Reasoning towards Explainable Recommendation

There has been significant progress in the utilization of heterogeneous knowledge graphs (KG) as auxiliary information in recommendation systems. Reasoning over KG paths sheds light on the user's decision making process. Previous methods focus on formulating this process as a multi-hop reasoning problem. However, without some form of guidance in the reasoning process, such a huge search space results in poor accuracy and little explanation diversity. In this paper, we propose UCPR, a user-centric path reasoning network that constantly guides the search from the aspect of user demand and enables explainable recommendation. In this network, a multi-view structure leverages not only local sequence reasoning information but also a panoramic view of the user's demand portfolio while inferring subsequent user decision-making steps. Experiments on five real-world benchmarks show UCPR is significantly more accurate than state-of-the-art methods. Besides, we show that the proposed model successfully identifies users' concerns and increases reasoning diversity to enhance explainability.