@article{nishida-etal-2026-dissecting,
    title = "Dissecting {G}raph{RAG}: A Modular Analysis of Knowledge Structuring for Factoid Question Answering",
    author = "Nishida, Noriki  and
      Munne, Rumana Ferdous  and
      Liu, Shanshan  and
      Tokunaga, Narumi  and
      Yamagata, Yuki  and
      Cheng, Fei  and
      Kozaki, Kouji  and
      Matsumoto, Yuji",
    journal = "Transactions of the Association for Computational Linguistics",
    volume = "14",
    year = "2026",
    address = "Cambridge, MA",
    publisher = "MIT Press",
    url = "https://preview.aclanthology.org/ingest-latest-mitpress-cl-tacl/2026.tacl-1.29/",
    doi = "10.1162/tacl.a.615",
    pages = "627--655",
    abstract = "We present a systematic analysis of module-level design choices in GraphRAG, a retrieval-augmented generation framework that integrates structured knowledge graphs into question answering. Focusing on triple extraction, community clustering, and report generation, we evaluate multiple strategies across two knowledge-intensive benchmarks. Our results show that high-quality triple extraction is critical, as the accuracy and coverage of the resulting knowledge graph can become a bottleneck for downstream reasoning. We also find that the granularity of fundamental knowledge units, as determined by community clustering, has a significant impact on downstream performance: Achieving a balance between factual detail and topical coherence within each unit is important to enable precise and comprehensive retrieval and to facilitate effective multi-hop reasoning. In addition, simple template-based reporting outperforms LLM-based summarization in both accuracy and efficiency. These findings provide practical guidance for the structure- aware design of retrieval-augmented systems."
}