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arXiv · 2404.11119

DREAM: A Dual Representation Learning Model for Multimodal Recommendation

Abstract

Multimodal recommendation focuses primarily on effectively exploiting both behavioral and multimodal information for the recommendation task. However, most existing models suffer from the following issues when fusing information from two different domains: (1) Previous works do not pay attention to the sufficient utilization of modal information by only using direct concatenation, addition, or simple linear layers for modal information extraction. (2) Previous works treat modal features as learnable embeddings, which causes the modal embeddings to gradually deviate from the original modal features during learning. We refer to this issue as Modal Information Forgetting. (3) Previous approaches fail to account for the significant differences in the distribution between behavior and modality, leading to the issue of representation misalignment. To address these challenges, this paper proposes a novel Dual REpresentAtion learning model for Multimodal Recommendation called DREAM. For sufficient information extraction, we introduce separate dual lines, including Behavior Line and Modal Line, in which the Modal-specific Encoder is applied to empower modal representations. To address the issue of Modal Information Forgetting, we introduce the Similarity Supervised Signal to constrain the modal representations. Additionally, we design a Behavior-Modal Alignment module to fuse the dual representations through Intra-Alignment and Inter-Alignment. Extensive experiments on three public datasets demonstrate that the proposed DREAM method achieves state-of-the-art (SOTA) results. The source code will be available upon acceptance.

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Kangning Zhang, Yingjie Qin, Jiarui Jin, Yifan Liu, Ruilong Su, Weinan Zhang, Yong Yu. 2024-04-17. DREAM: A Dual Representation Learning Model for Multimodal Recommendation. https://arxiv.org/abs/2404.11119

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