arXiv Machine Learning By Jie Yang, Zhengyu Fang, Zelin Xu, Jiarui Sun, Xiran Fan, Junpeng Wang, Liang Wang, Qinghua Liu, Yiwei Cai, Yan Zheng

LastOPD: Taming Collapse in Latent On-Policy Distillation

Read the original on arXiv Machine Learning →

The paper introduces LastOPD, a method that mitigates collapse in latent on‑policy distillation by applying latent supervision only to the last‑layer state during a brief cross‑fade into token‑level OPD. Experiments show that LastOPD improves MATH‑500 accuracy by 5.55 and 4.02 points over token‑only OPD when distilling Qwen3‑4B and Qwen3‑8B into Qwen3‑1.7B‑Base, and achieves comparable final scores in roughly half the training steps.

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