Sample Learning State Guided Dynamic SFT–RL Integration Post-training

Zheng Yang, Yilin Liu, Zhuoran Li, Wenhao Gao, Bingwei Li, Haozhe Sun, Caixia Yuan, Fan Wan, Wu Chen, Xiaojie Wang


Abstract
Integrating supervised fine-tuning (SFT) and reinforcement learning (RL) has become a common post-training paradigm for improving the reasoning capabilities of large language models. Existing methods typically rely on sequential SFT–RL pipelines or static loss weights, overlooking sample-level heterogeneity and evolving learning states. We propose Sample Learning State (SLS), a rollout-based characterization of each training sample using two complementary signals: sample mastery and exploration-trajectory dispersion. These signals estimate whether reward-driven updates are reliable for the core task and whether current rollouts provide informative contrast for RL optimization, respectively. Based on SLS, we design a state-aware coefficient that dynamically balances SFT and RL losses, increasing the RL weight only when the model demonstrates sufficient core-task competence and the sampled trajectories provide useful reward contrast. Experiments on Qwen2.5-Math models show that SLS achieves state-of-the-art results on four in-distribution and two out-of-distribution mathematical reasoning benchmarks. In multi-reward settings, SLS preserves core reasoning performance while mitigating reward hacking induced by auxiliary rewards.
Anthology ID:
2026.findings-emnlp.2011
Volume:
Findings of the Association for Computational Linguistics: EMNLP 2026
Month:
October
Year:
2026
Address:
Budapest, Hungary
Editors:
Hung-Yi Lee, Sunipa Dev, Jessy Li, Desmond Elliott
Venue:
Findings
SIG:
SIGDAT
Publisher:
Association for Computational Linguistics
Note:
Pages:
42798–42818
Language:
URL:
https://aclanthology.org/2026.findings-emnlp.2011/
DOI:
10.18653/2026.findings-emnlp.2011
Bibkey:
Cite (ACL):
Zheng Yang, Yilin Liu, Zhuoran Li, Wenhao Gao, Bingwei Li, Haozhe Sun, Caixia Yuan, Fan Wan, Wu Chen, and Xiaojie Wang. 2026. Sample Learning State Guided Dynamic SFT–RL Integration Post-training. In Findings of the Association for Computational Linguistics: EMNLP 2026, pages 42798–42818, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
Sample Learning State Guided Dynamic SFT–RL Integration Post-training (Yang et al., Findings 2026)
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PDF:
https://aclanthology.org/2026.findings-emnlp.2011.pdf