Don’t Forget the Base Retriever! A Low-Resource Graph-based Retriever for Multi-hop Question Answering (2025.emnlp-industry)
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Andre Melo, Enting Chen, Pavlos Vougiouklis, Chenxin Diao, Shriram Piramanayagam, Ruofei Lai, Jeff Z. Pan
| Challenge: | Existing GraphRAG approaches to multi-hop question answering rely on expensive LLM calls. |
| Approach: | They propose a lightweight, low-resource, multi-step graph-based retriever for multi-hop QA that performs multi- step retrieval in a few hundred milliseconds. |
| Outcome: | The proposed retriever outperforms conventional retrievers on multi-hop QA datasets and shows strong potential as a base retriever within multi-step agentic frameworks. |
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