Opinion spam has become a widespread problem in social media, where hired spammers write deceptive reviews to promote or demote products to mislead the consumers for profit or fame. Existing works mainly focus on manually designing discrete textual or behavior features, which cannot capture complex semantics of reviews. Although recent works apply deep learning methods to learn review-level semantic features, their models ignore the impact of the user-level and product-level information on learning review semantics and the inherent user-review-product relationship information. In this paper, we propose a Hierarchical Fusion Attention Network (HFAN) to automatically learn the semantics of reviews from the user and product level. Specifically, we design a multi-attention unit to extract user(product)-related review information. Then, we use orthogonal decomposition and fusion attention to learn a user, review, and product representation from the review information. Finally, we take the review as a relation between user and product entity and apply TransH to jointly encode this relationship into review representation. Experimental results obtained more than 10\% absolute precision improvement over the state-of-the-art performances on four real-world datasets, which show the effectiveness and versatility of the model.

提出一种用于自动学习用户和产品层次的评论语义的HFAN方法，包括设计多重注意单元以提取用户（产品）相关评论信息、使用正交分解和融合注意力从评论信息中学习用户、评论和产品表示以及将评论作为用户和产品实体之间的关系并将其编码为评论表示。实验结果表明此方法在四个真实数据集上表现优于现有方法。

从用户和产品级别信息中学习评论表示以进行垃圾邮件检测