This research examines the data efficiency of Reinforcement Learning with Verifiable Reward (RLVR) when applied to large language models for mathematical reasoning tasks. The paper's most significant finding is the success of 1-shot RLVR, showing that comparable performance to using a large training dataset can be achieved using just a single, carefully selected example. This result suggests that RLVR is effective primarily because it activates the strong latent reasoning capabilities already present in the base model, rather than imparting new domain knowledge. An interesting phenomenon observed during training is "post-saturation generalization," where the model's test performance continues to rise long after training accuracy has saturated and the model has begun overfitting the single example. Ablation studies indicate that while policy gradient loss is the main source of improvement, entropy loss is essential for encouraging the exploration needed to realize this enhanced long-term generalization.

Source:

https://openreview.net/pdf?id=IBrRNLr6JA