TMR-GGNN: Credit Card Fraud Detection based on Time-Aware Multi-Relational Guided Graph Neural Network
This work addresses the challenges of extreme class imbalance, dynamically evolving fraud patterns, and complex transactional relationships in credit card fraud detection by proposing a temporal-aware multi-relational graph neural network. The method constructs a dynamic multi-relational graph and employs a temporal relational attention mechanism to adaptively model both semantic and temporal dependencies among transactions. To enhance discrimination of rare fraud patterns, contrastive learning is integrated into the decoder. The model is jointly optimized using InfoNCE loss and Focal Loss, effectively mitigating the class imbalance issue. Experimental results demonstrate that the proposed approach significantly improves fraud detection accuracy, reduces false negatives, and exhibits superior generalization performance under highly imbalanced conditions.