SAPO: Step-Aligned Policy Optimization for Reasoning-Based Generative Recommendation

In three linesSAPO improves generative recommendation by aligning reinforcement learning optimization to individual reasoning steps. Instead of assigning a single advantage to the entire response, SAPO computes separate group-relative advantages for each reasoning step and SID token, stabilizing training and outperforming baselines across three real-world datasets.

Summary generated by Claude — human-verified