Thinking Machines Lab explains on-policy distillation for post-training small models
AIThinking Machines Lab explains on-policy distillation, which samples rollouts from a student model and has a teacher grade each token by reverse KL. The post reports that it matched RL-trained reasoning on AIME'24 at about one-tenth the cost, reaching 70% from a 400k-prompt SFT checkpoint in about 150 steps.
Why it matters: The post compares on-policy distillation with RL and SFT using compute figures, showing how dense per-token teacher feedback can cut post-training cost.