12 Jan 2024 | Binghai Wang*, Rui Zheng*, Lu Chen*, Yan Liu*, Shihan Dou, Caishuang Huang, Wei Shen, Senjie Jin, Enyu Zhou, Chenyu Shi, Songyang Gao, Nuo Xu, Yuhao Zhou, Xiaoran Fan, Zhiheng Xi, Jun Zhao, Xiao Wang, Tao Ji, Hang Yan, Lixing Shen*, Zhan Chen*, Tao Gui†, Qi Zhang†, Xipeng Qiu, Xuanjing Huang, Zuxuan Wu, Yu-Gang Jiang
This paper explores the challenges and solutions in reward modeling for Reinforcement Learning from Human Feedback (RLHF) in large language models. Reward models are crucial for aligning language models with human preferences, but they face challenges such as noisy and ambiguous preference data, and poor generalization to out-of-distribution (OOD) examples. The authors propose methods to address these issues.
First, they introduce a preference strength measurement metric based on multi-reward model voting. This metric helps identify and mitigate the impact of incorrect and ambiguous preferences in the dataset. They also introduce an adaptive margin in the loss function to better distinguish between similar responses.
Second, they explore contrastive learning and meta-learning to enhance the reward model's ability to generalize. Contrastive learning helps the model distinguish between chosen and rejected responses, while meta-learning enables the model to maintain the ability to differentiate subtle differences in OOD samples.
The authors also demonstrate that using these methods leads to more stable reinforcement learning processes and improved alignment performance. They open-source their training code, the Anthropic's HHRLHF dataset with preference strength information, and a validation set cleaned by GPT-4.
The paper shows that preference data with varying strengths can significantly impact reward model performance. They propose methods to handle incorrect and ambiguous data, including label flipping and label smoothing. They also introduce an adaptive margin to improve the model's ability to distinguish between responses.
The authors evaluate their methods on various datasets and find that their approach outperforms baselines in terms of alignment performance and generalization. They also show that their method is effective in both in-distribution and out-of-distribution scenarios, with the latter showing a slight decline in performance due to distribution shifts.
Overall, the paper presents a comprehensive approach to improving reward modeling in RLHF, addressing key challenges in preference data and enhancing the model's generalization capabilities.This paper explores the challenges and solutions in reward modeling for Reinforcement Learning from Human Feedback (RLHF) in large language models. Reward models are crucial for aligning language models with human preferences, but they face challenges such as noisy and ambiguous preference data, and poor generalization to out-of-distribution (OOD) examples. The authors propose methods to address these issues.
First, they introduce a preference strength measurement metric based on multi-reward model voting. This metric helps identify and mitigate the impact of incorrect and ambiguous preferences in the dataset. They also introduce an adaptive margin in the loss function to better distinguish between similar responses.
Second, they explore contrastive learning and meta-learning to enhance the reward model's ability to generalize. Contrastive learning helps the model distinguish between chosen and rejected responses, while meta-learning enables the model to maintain the ability to differentiate subtle differences in OOD samples.
The authors also demonstrate that using these methods leads to more stable reinforcement learning processes and improved alignment performance. They open-source their training code, the Anthropic's HHRLHF dataset with preference strength information, and a validation set cleaned by GPT-4.
The paper shows that preference data with varying strengths can significantly impact reward model performance. They propose methods to handle incorrect and ambiguous data, including label flipping and label smoothing. They also introduce an adaptive margin to improve the model's ability to distinguish between responses.
The authors evaluate their methods on various datasets and find that their approach outperforms baselines in terms of alignment performance and generalization. They also show that their method is effective in both in-distribution and out-of-distribution scenarios, with the latter showing a slight decline in performance due to distribution shifts.
Overall, the paper presents a comprehensive approach to improving reward modeling in RLHF, addressing key challenges in preference data and enhancing the model's generalization capabilities.