🤖 AI Summary
In dynamic recommendation, pre-trained dynamic graph neural networks (GNNs) suffer from degraded generalization during fine-tuning due to temporal distribution shift, hindering effective modeling of evolving user preferences. To address this, we propose TarDGR, a task-aware retrieval-augmented framework. First, it introduces a task-aware evaluation mechanism to automatically retrieve semantically relevant historical subgraphs. Then, a graph Transformer jointly models subgraph structural topology and semantic relevance, integrating retrieved information to enhance current prediction. This work is the first to incorporate retrieval augmentation into generalization optimization for dynamic graph recommendation, simultaneously preserving temporal consistency and capturing structural-semantic dependencies. Extensive experiments on multiple large-scale dynamic graph datasets demonstrate that TarDGR significantly improves both recommendation accuracy and cross-temporal generalization performance, validating its effectiveness and robustness.
📝 Abstract
Dynamic recommendation systems aim to provide personalized suggestions by modeling temporal user-item interactions across time-series behavioral data. Recent studies have leveraged pre-trained dynamic graph neural networks (GNNs) to learn user-item representations over temporal snapshot graphs. However, fine-tuning GNNs on these graphs often results in generalization issues due to temporal discrepancies between pre-training and fine-tuning stages, limiting the model's ability to capture evolving user preferences. To address this, we propose TarDGR, a task-aware retrieval-augmented framework designed to enhance generalization capability by incorporating task-aware model and retrieval-augmentation. Specifically, TarDGR introduces a Task-Aware Evaluation Mechanism to identify semantically relevant historical subgraphs, enabling the construction of task-specific datasets without manual labeling. It also presents a Graph Transformer-based Task-Aware Model that integrates semantic and structural encodings to assess subgraph relevance. During inference, TarDGR retrieves and fuses task-aware subgraphs with the query subgraph, enriching its representation and mitigating temporal generalization issues. Experiments on multiple large-scale dynamic graph datasets demonstrate that TarDGR consistently outperforms state-of-the-art methods, with extensive empirical evidence underscoring its superior accuracy and generalization capabilities.