自适应调节正则化强度,让生成模型在探索与优化间更好平衡。
Adaptive Divergence Regularized Policy Optimization for Fine-tuning Generative Models
- 根据优势估计动态调整正则化强度,高价值样本少约束,低质量样本强约束。
- 20亿参数模型在属性绑定等任务上超越48亿和120亿参数大模型。
- 适用于文本、多模态等多种生成模型,可直接替换现有强化学习方法。
生成模型在强化学习微调中平衡探索与利用是一项关键挑战,现有方法依赖固定发散正则化,导致两难:强正则化虽能保留模型能力但限制奖励优化,弱正则化虽利于对齐却可能引发不稳定或奖励欺骗。本文提出自适应发散正则化策略优化(ADRPO),依据优势估计自动调节正则化强度——对高价值样本减少约束,对低质量样本施加强正则化,使策略能根据数据质量灵活切换探索与激进利用。在流匹配生成模型中结合Wasserstein-2正则化,ADRPO在文生图任务上表现优异,优于离线方法DPO及在线方法ORW-CFM-W2。一个20亿参数的SD3模型在属性绑定、语义一致性、艺术风格迁移和组合控制上超越48亿和120亿参数模型,同时保持生成多样性。ADRPO可推广至基于KL的文本语言模型与多模态推理模型微调,提升GRPO等在线强化学习方法。在语言模型微调中,表现出逃逸局部最优的涌现探索能力;在多模态音频推理中,通过更优的逐步推理能力超越GRPO,使70亿参数模型优于显著更大的商业模型如Gemini 2.5 Pro与GPT-4o Audio,提供一种通用、即插即用的探索-利用平衡解决方案。
原文摘要 · Abstract (English)
Balancing exploration and exploitation during reinforcement learning fine-tuning of generative models presents a critical challenge, as existing approaches rely on fixed divergence regularization that creates an inherent dilemma: strong regularization preserves model capabilities but limits reward optimization, while weak regularization enables greater alignment but risks instability or reward hacking. We introduce Adaptive Divergence Regularized Policy Optimization (ADRPO), which automatically adjusts regularization strength based on advantage estimates-reducing regularization for high-value samples while applying stronger regularization to poor samples, enabling policies to navigate between exploration and aggressive exploitation according to data quality. Our implementation with Wasserstein-2 regularization for flow matching generative models achieves remarkable results on text-to-image generation, achieving better semantic alignment and diversity than offline methods like DPO and online methods with fixed regularization like ORW-CFM-W2. ADRPO enables a 2B parameter SD3 model to surpass much larger models with 4.8B and 12B parameters in attribute binding, semantic consistency, artistic style transfer, and compositional control while maintaining generation diversity. ADRPO generalizes to KL-regularized fine-tuning of both text-only LLMs and multi-modal reasoning models, enhancing existing online RL methods like GRPO. In LLM fine-tuning, ADRPO demonstrates an emergent ability to escape local optima through active exploration, while in multi-modal audio reasoning, it outperforms GRPO through superior step-by-step reasoning, enabling a 7B model to outperform substantially larger commercial models including Gemini 2.5 Pro and GPT-4o Audio, offering an effective plug-and-play solution to the exploration-exploitation challenge across diverse generative architectures and modalities.
Thank you to arXiv for use of its open access interoperability. PaperDance 不是 arXiv 官方产品;中文卡片由大模型生成,请以原文为准。