Multi-hop reasoning with fine-grained entity representations and LLM-augmented actions over few-shot knowledge graphs
摘要
Multi-hop reasoning on knowledge graphs (KGs) has emerged as a cornerstone for inferring missing facts, offering an explainable reasoning process and accurate reasoning results via reinforcement learning (RL) paradigms. However, their reasoning effectiveness drops sharply in few-shot relations (containing only a few triples) due to insufficient training instances. Although previous works have utilized meta-reinforcement learning (MRL) and reward engineering to improve the adaptability of models in few-shot scenarios, they often overlook two critical challenges: (1) coarse entity representations that fail to capture high-order contextual dependencies essential for nuanced reasoning, and (2) inherently sparse action spaces caused by few-shot relations, which restrict the exploration of valid multi-hop paths. To address these limitations, we introduce a multi-hop reasoning method with fine-grained entity representations and LLM-augmented actions (MIRAGE), a novel framework that fuses fine-grained entity representations with an action-augmented MRL paradigm. Specifically, our framework consists of two core modules: (1) a context-aware representation module that captures query-related dependencies from neighboring entities to produce fine-grained embeddings, and (2) an action-augmented meta-reinforcement learning module that leverages large language models (LLMs) to generate supplementary actions for the agent to expand the action space. By combining fine-grained semantics with dynamically supplementary actions, MIRAGE can conduct multi-hop reasoning by effectively combining multi-step paths over few-shot knowledge graphs. Finally, comprehensive evaluations on benchmark datasets reveal that MIRAGE outperforms state-of-the-art baselines in few-shot scenarios.