Two is Better than Many? Binary Classification as an Effective Approach to Multi-Choice Question Answering
Deepanway Ghosal, Navonil Majumder, Rada Mihalcea, Soujanya Poria
Abstract
We propose a simple refactoring of multi-choice question answering (MCQA) tasks as a series of binary classifications. The MCQA task is generally performed by scoring each (question, answer) pair normalized over all the pairs, and then selecting the answer from the pair that yield the highest score. For n answer choices, this is equivalent to an n-class classification setup where only one class (true answer) is correct. We instead show that classifying (question, true answer) as positive instances and (question, false answer) as negative instances is significantly more effective across various models and datasets. We show the efficacy of our proposed approach in different tasks – abductive reasoning, commonsense question answering, science question answering, and sentence completion. Our DeBERTa binary classification model reaches the top or close to the top performance on public leaderboards for these tasks. The source code of the proposed approach is available at https://github.com/declare-lab/TEAM.- Anthology ID:
- 2022.emnlp-main.691
- Volume:
- Proceedings of the 2022 Conference on Empirical Methods in Natural Language Processing
- Month:
- December
- Year:
- 2022
- Address:
- Abu Dhabi, United Arab Emirates
- Editors:
- Yoav Goldberg, Zornitsa Kozareva, Yue Zhang
- Venue:
- EMNLP
- SIG:
- Publisher:
- Association for Computational Linguistics
- Note:
- Pages:
- 10158–10166
- Language:
- URL:
- https://aclanthology.org/2022.emnlp-main.691
- DOI:
- 10.18653/v1/2022.emnlp-main.691
- Cite (ACL):
- Deepanway Ghosal, Navonil Majumder, Rada Mihalcea, and Soujanya Poria. 2022. Two is Better than Many? Binary Classification as an Effective Approach to Multi-Choice Question Answering. In Proceedings of the 2022 Conference on Empirical Methods in Natural Language Processing, pages 10158–10166, Abu Dhabi, United Arab Emirates. Association for Computational Linguistics.
- Cite (Informal):
- Two is Better than Many? Binary Classification as an Effective Approach to Multi-Choice Question Answering (Ghosal et al., EMNLP 2022)
- PDF:
- https://preview.aclanthology.org/ingest-acl-2023-videos/2022.emnlp-main.691.pdf