OPDArena: Understanding Learning and Forgetting in On-Policy Distillation
On-policy distillation (OPD) is increasingly used for language model post-training, yet how teacher supervision shapes learning and forgetting remains unclear.
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Key points
- We present OPDArena, a framework comparing supervised fine-tuning (SFT), reinforcement learning with verifiable rewards (RLVR), and OPD across five pretrained models and diverse teacher sources.
- Teacher choice strongly shapes retention: students of RLVR-trained teachers improve on the target task while retaining prior capabilities, whereas students of SFT-trained teachers incur greater capability loss.
- Across post-training methods, out-of-domain (OOD) distribution change shows a more consistent positive association with forgetting than in-domain change.
- Controlled teacher comparisons show that the task-specific preferences teachers acquire through post-training make student updates more concentrated in-domain.
Sources (1)
- [1]OPDArena: Understanding Learning and Forgetting in On-Policy DistillationarXiv (AI, ML, NLP, CV, robotics, multi-agent) · Oct 19, 01:51 AM
On-policy distillation (OPD) is increasingly used for language model post-training, yet how teacher supervision shapes learning and forgetting remains unclear.
We present OPDArena, a framework comparing supervised fine-tuning (SFT), reinforcement learning with verifiable rewards (RLVR), and OPD across five pretrained models and diverse teacher sources.
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Before this
- Oct 18, 2026From Unverifiable Domain Text to Cross-Lingual RLVR via Code-Switched Task Synthesis
- Oct 18, 2026Conformal Prediction-Enabled Sequence-level Policy Optimization for Reasoning Language Models
- Oct 18, 2026Beyond the Teacher: Understanding and Preserving Distillation Overshoot in Agentic On-Policy Distillation
- Oct 17, 2026Which Long Documents Matter? A Controlled Study of Data Selection for Context Extension
- Oct 16, 2026SimOPD: Relational Knowledge Transfer for On-Policy Distillation
- Oct 16, 2026A Stronger Teacher Within: Strengthening MoE Models via On-Policy Bidirectional Distillation