MRML: Multimodal Rumor Detection by Deep Metric Learning

Multimodal rumor detection aims at detecting rumors using information from textual and visual modalities. The most critical difficulty in multimodal rumor detection lies in capturing both the intra-modal and inter-modal relationships from multimodal data. However, existing methods mainly focus on the multimodal fusion process while paying little attention to the intra-modal relationships. To address these limitations, we propose a multimodal rumor detection method with deep metric learning (MRML) to effectively extract multimodal relationships of news for detecting rumors. Specifically, we design the metric-based triplet learning to extract the intra-modal relationships between rumors and non-rumors in every modality and the contrastive pairwise learning to capture the inter-modal relationships across multimodal. Extensive experiments on two real-world multimodal datasets show the superior performance of our rumor detection method.