Direct Preference Optimization for Chatbot Fine-Tuning: An Empirical Study

Dezhi Yu; Yvonne Qiu; ShuoJia Fu

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arXiv · 2606.12881

Direct Preference Optimization for Chatbot Fine-Tuning: An Empirical Study

Dezhi Yu·Yvonne Qiu·ShuoJia Fu

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Abstract

We present an approach to fine-tuning large language models using Direct Preference Optimization (DPO), a reinforcement learning technique. Our experimental results demonstrate that DPO simplifies the training pipeline, improves computational efficiency, and achieves competitive performance. The evaluation using BLEU, ROUGE, and cosine similarity metrics indicates effective learning and convergence, though further investigation is needed to address observed training instability.

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Dezhi Yu, Yvonne Qiu, ShuoJia Fu. 2026-06-11. Direct Preference Optimization for Chatbot Fine-Tuning: An Empirical Study. https://arxiv.org/abs/2606.12881

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