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arXiv · 2106.06900

Deep Reinforcement Learning based Group Recommender System

Zefang Liu·Shuran Wen·Yinzhu Quan
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Abstract

Group recommender systems are widely used in current web applications. In this paper, we propose a novel group recommender system based on the deep reinforcement learning. We introduce the MovieLens data at first and generate one random group dataset, MovieLens-Rand, from it. This randomly generated dataset is described and analyzed. We also present experimental settings and two state-of-art baselines, AGREE and GroupIM. The framework of our novel model, the Deep Reinforcement learning based Group Recommender system (DRGR), is proposed. Actor-critic networks are implemented with the deep deterministic policy gradient algorithm. The DRGR model is applied on the MovieLens-Rand dataset with two baselines. Compared with baselines, we conclude that DRGR performs better than GroupIM due to long interaction histories but worse than AGREE because of the self-attention mechanism. We express advantages and shortcomings of DRGR and also give future improvement directions at the end.

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Zefang Liu, Shuran Wen, Yinzhu Quan. 2021-06-13. Deep Reinforcement Learning based Group Recommender System. https://arxiv.org/abs/2106.06900

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