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DOI 10.34229/KCA2522-9664.26.4.2
UDC 004.89

R. Pravosud
Taras Shevchenko National University of Kyiv, Kyiv, Ukraine,
pronod9999@gmail.com

O. Marchenko
Taras Shevchenko National University of Kyiv, Kyiv, Ukraine,
omarchenko@univ.kiev.ua


DIALOGUE STYLE TRANSFER FOR MULTIPLE CHARACTERS

Abstract. Dialogue style transfer aims to generate responses that preserve semantic coherence while adhering to a specified stylistic persona. Recent work has shown that reinforcement learning combined with parameter-efficient fine-tuning can effectively optimize stylistic objectives, but existing approaches are typically limited to a single character or rely on large, resource-intensive models. In this paper, we present a unified reinforcement learning framework for multi-character dialogue style transfer that is scalable to small, distilled, and quantized language models. Our approach combines Proximal Policy Optimization with Low-Rank Adaptation and a multi-class style reward model, enabling a single model to generate dialogue in multiple philosophical character styles through explicit conditioning. We evaluate the proposed method across multiple model sizes, including GPT2-Large, GPT2, DistilGPT2, and INT8-quantized GPT2, and compare against untuned GPT2 baselines. Experimental results show that reinforcement learning substantially improves stylistic accuracy over untuned models, while smaller models retain most of the performance at significantly reduced computational cost. These findings demonstrate that the proposed framework is effective, scalable, and suitable for deployment in low-resource environments.

Keywords: dialogue generation, NLP, reinforcement learning, style transfer, PEFT, PPO.


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