GRPO Amplifies the Success Rate of A Policy via An implicit Fixed Point Iteration

In the previous post , we established that GRPO with verifiable rewards can be seen as a weighted contastive policy optimization, where positive and negative samples are synthetic data sampled from the old policy and labeled via the verifiable reward. In this post we will review our recent preprint that builds on this observation and analyses the dynamics of GRPO and the probability of success of…