ECO Decoding: Entropy-Based Control for Controllability and Fluency in Controllable Dialogue Generation

Seungmin Shin, Dooyoung Kim, Youngjoong Ko


Abstract
Controllable Dialogue Generation (CDG) enables chatbots to generate responses with desired attributes, and weighted decoding methods have achieved significant success in the CDG task. However, using a fixed constant value to manage the bias of attribute probabilities makes it challenging to find an ideal control strength that satisfies both controllability and fluency. To address this issue, we propose ECO decoding Entropy-based COntrol, which dynamically adjusts the control strength at each generation step according to the model’s entropy in both the language model and attribute classifier probability distributions. Experimental results on DailyDialog and MultiWOZ datasets show that our method achieves improved control accuracy while maintaining fluency and grammar, outperforming previous decoding methods across various models and settings. Furthermore, ECO decoding alleviates probability interpolation issues in multi-attribute generation, demonstrating its robust performance in both single and multi-attribute scenarios.
Anthology ID:
2025.emnlp-main.1437
Volume:
Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing
Month:
November
Year:
2025
Address:
Suzhou, China
Editors:
Christos Christodoulopoulos, Tanmoy Chakraborty, Carolyn Rose, Violet Peng
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EMNLP
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Publisher:
Association for Computational Linguistics
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Pages:
28297–28309
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https://preview.aclanthology.org/ingest-emnlp/2025.emnlp-main.1437/
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Cite (ACL):
Seungmin Shin, Dooyoung Kim, and Youngjoong Ko. 2025. ECO Decoding: Entropy-Based Control for Controllability and Fluency in Controllable Dialogue Generation. In Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing, pages 28297–28309, Suzhou, China. Association for Computational Linguistics.
Cite (Informal):
ECO Decoding: Entropy-Based Control for Controllability and Fluency in Controllable Dialogue Generation (Shin et al., EMNLP 2025)
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