Multi-hop Reading Comprehension through Question Decomposition and Rescoring
Sewon Min, Victor Zhong, Luke Zettlemoyer, Hannaneh Hajishirzi
Abstract
Multi-hop Reading Comprehension (RC) requires reasoning and aggregation across several paragraphs. We propose a system for multi-hop RC that decomposes a compositional question into simpler sub-questions that can be answered by off-the-shelf single-hop RC models. Since annotations for such decomposition are expensive, we recast subquestion generation as a span prediction problem and show that our method, trained using only 400 labeled examples, generates sub-questions that are as effective as human-authored sub-questions. We also introduce a new global rescoring approach that considers each decomposition (i.e. the sub-questions and their answers) to select the best final answer, greatly improving overall performance. Our experiments on HotpotQA show that this approach achieves the state-of-the-art results, while providing explainable evidence for its decision making in the form of sub-questions.- Anthology ID:
- P19-1613
- Volume:
- Proceedings of the 57th Annual Meeting of the Association for Computational Linguistics
- Month:
- July
- Year:
- 2019
- Address:
- Florence, Italy
- Editors:
- Anna Korhonen, David Traum, Lluís Màrquez
- Venue:
- ACL
- SIG:
- Publisher:
- Association for Computational Linguistics
- Note:
- Pages:
- 6097–6109
- Language:
- URL:
- https://preview.aclanthology.org/icon-24-ingestion/P19-1613/
- DOI:
- 10.18653/v1/P19-1613
- Cite (ACL):
- Sewon Min, Victor Zhong, Luke Zettlemoyer, and Hannaneh Hajishirzi. 2019. Multi-hop Reading Comprehension through Question Decomposition and Rescoring. In Proceedings of the 57th Annual Meeting of the Association for Computational Linguistics, pages 6097–6109, Florence, Italy. Association for Computational Linguistics.
- Cite (Informal):
- Multi-hop Reading Comprehension through Question Decomposition and Rescoring (Min et al., ACL 2019)
- PDF:
- https://preview.aclanthology.org/icon-24-ingestion/P19-1613.pdf
- Code
- shmsw25/DecompRC + additional community code
- Data
- HotpotQA