Reinforcement Replaces Supervision: Query focused Summarization using Deep Reinforcement Learning

Swaroop Nath, Pushpak Bhattacharyya, Harshad Khadilkar


Abstract
Query-focused Summarization (QfS) deals with systems that generate summaries from document(s) based on a query. Motivated by the insight that Reinforcement Learning (RL) provides a generalization to Supervised Learning (SL) for Natural Language Generation, and thereby performs better (empirically) than SL, we use an RL-based approach for this task of QfS. Additionally, we also resolve the conflict of employing RL in Transformers with Teacher Forcing. We develop multiple Policy Gradient networks, trained on various reward signals: ROUGE, BLEU, and Semantic Similarity, which lead to a 10-point improvement over the State-of-the-Art approach on the ROUGE-L metric for a benchmark dataset (ELI5). We also show performance of our approach in zero-shot setting for another benchmark dataset (DebatePedia) – our approach leads to results comparable to baselines, which were specifically trained on DebatePedia. To aid the RL training, we propose a better semantic similarity reward, enabled by a novel Passage Embedding scheme developed using Cluster Hypothesis. Lastly, we contribute a gold-standard test dataset to further research in QfS and Long-form Question Answering (LfQA).
Anthology ID:
2023.emnlp-main.977
Volume:
Proceedings of the 2023 Conference on Empirical Methods in Natural Language Processing
Month:
December
Year:
2023
Address:
Singapore
Editors:
Houda Bouamor, Juan Pino, Kalika Bali
Venue:
EMNLP
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
15770–15789
Language:
URL:
https://aclanthology.org/2023.emnlp-main.977
DOI:
10.18653/v1/2023.emnlp-main.977
Bibkey:
Cite (ACL):
Swaroop Nath, Pushpak Bhattacharyya, and Harshad Khadilkar. 2023. Reinforcement Replaces Supervision: Query focused Summarization using Deep Reinforcement Learning. In Proceedings of the 2023 Conference on Empirical Methods in Natural Language Processing, pages 15770–15789, Singapore. Association for Computational Linguistics.
Cite (Informal):
Reinforcement Replaces Supervision: Query focused Summarization using Deep Reinforcement Learning (Nath et al., EMNLP 2023)
Copy Citation:
PDF:
https://aclanthology.org/2023.emnlp-main.977.pdf
Video:
 https://aclanthology.org/2023.emnlp-main.977.mp4