Hybrid Graphs for Table-and-Text based Question Answering using LLMs

Ankush Agarwal, Chaitanya Devaguptapu, Ganesh S


Abstract
Answering questions that require reasoning and aggregation across both structured (tables) and unstructured (raw text) data sources presents significant challenges. Current methods rely on fine-tuning and high-quality, human-curated data, which is difficult to obtain. Recent advances in Large Language Models (LLMs) have shown promising results for multi-hop question answering (QA) over single-source text data in a zero-shot setting, yet exploration into multi-source Table-Text QA remains limited. In this paper, we present a novel Hybrid Graph-based approach for Table-Text QA that leverages LLMs without fine-tuning. Our method constructs a unified Hybrid Graph from textual and tabular data, pruning information based on the input question to provide the LLM with relevant context concisely. We evaluate our approach on the challenging Hybrid-QA and OTT-QA datasets using state-of-the-art LLMs, including GPT-3.5, GPT-4, and LLaMA-3. Our method achieves the best zero-shot performance on both datasets, improving Exact Match scores by up to 10% on Hybrid-QA and 5.4% on OTT-QA. Moreover, our approach reduces token usage by up to 53% compared to the original context.
Anthology ID:
2025.naacl-long.39
Volume:
Proceedings of the 2025 Conference of the Nations of the Americas Chapter of the Association for Computational Linguistics: Human Language Technologies (Volume 1: Long Papers)
Month:
April
Year:
2025
Address:
Albuquerque, New Mexico
Editors:
Luis Chiruzzo, Alan Ritter, Lu Wang
Venue:
NAACL
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
858–875
Language:
URL:
https://preview.aclanthology.org/fix-sig-urls/2025.naacl-long.39/
DOI:
Bibkey:
Cite (ACL):
Ankush Agarwal, Chaitanya Devaguptapu, and Ganesh S. 2025. Hybrid Graphs for Table-and-Text based Question Answering using LLMs. In Proceedings of the 2025 Conference of the Nations of the Americas Chapter of the Association for Computational Linguistics: Human Language Technologies (Volume 1: Long Papers), pages 858–875, Albuquerque, New Mexico. Association for Computational Linguistics.
Cite (Informal):
Hybrid Graphs for Table-and-Text based Question Answering using LLMs (Agarwal et al., NAACL 2025)
Copy Citation:
PDF:
https://preview.aclanthology.org/fix-sig-urls/2025.naacl-long.39.pdf