reward-learning

GFT (Group Fine-Tuning) is a unified post-training framework for LLMs that addresses limitations of supervised fine-tuning by using Group Advantage Learning and Dynamic Coefficient Rectification to improve training stability and generalization. The paper shows SFT can be interpreted as a special case of policy gradient optimization with sparse implicit rewards, and GFT consistently outperforms SFT-based methods while integrating more smoothly with subsequent RL training.