Large language models are often trained either by supervised fine-tuning (SFT), learning from correct answers, or by reinforcement learning (RL), learning from trial and error with rewards. Many believe RL generalizes while SFT memorizes. This paper reexamines that.
Researchers compared SFT and RL on reasoning tasks. They varied the source of SFT data, using correct solutions from different models, and the amount of data, giving SFT the same number of training examples as RL.
With a diverse mix and enough data, SFT matched RL on new problems, sometimes even better. This shows data quality and scale matter more than the training method. SFT, being simpler, can be just as effective for generalizable reasoning.
