Query Symbolically or Retrieve Semantically? A Dataset and Method for Semi-Structured Question Answering

Mateusz Czyżnikiewicz, Ryszard Tuora, Adam Kozakiewicz, Tomasz Ziętkiewicz, Mateusz Galiński, Michał Tomasz Godziszewski, Michal P. Karpowicz, Timothy Hospedales, Cristina Cornelio


Abstract
Retrieval-Augmented Generation (RAG) systems for question answering typically retrieve evidence by semantic similarity between the query and document chunks. While effective for unstructured text, this approach is less reliable on semi-structured corpora where answering may require exact filtering, aggregation, or exhaustive retrieval over structured attributes across multiple documents. Symbolic approaches support such operations, but they are often brittle on noisy natural-language corpora. We address this gap with DualGraph, a RAG framework that represents documents through two complementary views: a Textual Knowledge Graph for semantic retrieval and a Symbolic Knowledge Graph for symbolic querying over typed subject–predicate–object triples. Building on these two components, we provide multiple strategies for selecting or combining semantic and symbolic evidence. We also introduce SpecsQA, a benchmark from a commercial shopping website with semi-structured product documents and manually curated questions spanning open-ended and specification-oriented retrieval. Experiments show that DualGraph consistently outperforms state-of-the-art dense-retrieval, GraphRAG, symbolic, and table-oriented baselines across question types. Code and data are available at https://github.com/corneliocristina/DualGraphRAG.
Anthology ID:
2026.findings-emnlp.1319
Volume:
Findings of the Association for Computational Linguistics: EMNLP 2026
Month:
October
Year:
2026
Address:
Budapest, Hungary
Editors:
Hung-Yi Lee, Sunipa Dev, Jessy Li, Desmond Elliott
Venue:
Findings
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SIGDAT
Publisher:
Association for Computational Linguistics
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Pages:
27929–27960
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URL:
https://aclanthology.org/2026.findings-emnlp.1319/
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Cite (ACL):
Mateusz Czyżnikiewicz, Ryszard Tuora, Adam Kozakiewicz, Tomasz Ziętkiewicz, Mateusz Galiński, Michał Tomasz Godziszewski, Michal P. Karpowicz, Timothy Hospedales, and Cristina Cornelio. 2026. Query Symbolically or Retrieve Semantically? A Dataset and Method for Semi-Structured Question Answering. In Findings of the Association for Computational Linguistics: EMNLP 2026, pages 27929–27960, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
Query Symbolically or Retrieve Semantically? A Dataset and Method for Semi-Structured Question Answering (Czyżnikiewicz et al., Findings 2026)
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https://aclanthology.org/2026.findings-emnlp.1319.pdf