Research

Paper

AI LLM February 24, 2026

Actor-Curator: Co-adaptive Curriculum Learning via Policy-Improvement Bandits for RL Post-Training

Authors

Zhengyao Gu, Jonathan Light, Raul Astudillo, Ziyu Ye, Langzhou He, Henry Peng Zou, Wei Cheng, Santiago Paternain, Philip S. Yu, Yisong Yue

Abstract

Post-training large foundation models with reinforcement learning typically relies on massive and heterogeneous datasets, making effective curriculum learning both critical and challenging. In this work, we propose ACTOR-CURATOR, a scalable and fully automated curriculum learning framework for reinforcement learning post-training of large language models (LLMs). ACTOR-CURATOR learns a neural curator that dynamically selects training problems from large problem banks by directly optimizing for expected policy performance improvement. We formulate problem selection as a non-stationary stochastic bandit problem, derive a principled loss function based on online stochastic mirror descent, and establish regret guarantees under partial feedback. Empirically, ACTOR-CURATOR consistently outperforms uniform sampling and strong curriculum baselines across a wide range of challenging reasoning benchmarks, demonstrating improved training stability and efficiency. Notably, it achieves relative gains of 28.6% on AIME2024 and 30.5% on ARC-1D over the strongest baseline and up to 80% speedup. These results suggest that ACTOR-CURATOR is a powerful and practical approach for scalable LLM post-training.

Metadata

arXiv ID: 2602.20532
Provider: ARXIV
Primary Category: cs.LG
Published: 2026-02-24
Fetched: 2026-02-25 06:05

Related papers

Raw Data (Debug)
{
  "raw_xml": "<entry>\n    <id>http://arxiv.org/abs/2602.20532v1</id>\n    <title>Actor-Curator: Co-adaptive Curriculum Learning via Policy-Improvement Bandits for RL Post-Training</title>\n    <updated>2026-02-24T04:19:48Z</updated>\n    <link href='https://arxiv.org/abs/2602.20532v1' rel='alternate' type='text/html'/>\n    <link href='https://arxiv.org/pdf/2602.20532v1' rel='related' title='pdf' type='application/pdf'/>\n    <summary>Post-training large foundation models with reinforcement learning typically relies on massive and heterogeneous datasets, making effective curriculum learning both critical and challenging. In this work, we propose ACTOR-CURATOR, a scalable and fully automated curriculum learning framework for reinforcement learning post-training of large language models (LLMs). ACTOR-CURATOR learns a neural curator that dynamically selects training problems from large problem banks by directly optimizing for expected policy performance improvement. We formulate problem selection as a non-stationary stochastic bandit problem, derive a principled loss function based on online stochastic mirror descent, and establish regret guarantees under partial feedback. Empirically, ACTOR-CURATOR consistently outperforms uniform sampling and strong curriculum baselines across a wide range of challenging reasoning benchmarks, demonstrating improved training stability and efficiency. Notably, it achieves relative gains of 28.6% on AIME2024 and 30.5% on ARC-1D over the strongest baseline and up to 80% speedup. These results suggest that ACTOR-CURATOR is a powerful and practical approach for scalable LLM post-training.</summary>\n    <category scheme='http://arxiv.org/schemas/atom' term='cs.LG'/>\n    <category scheme='http://arxiv.org/schemas/atom' term='cs.AI'/>\n    <category scheme='http://arxiv.org/schemas/atom' term='cs.CL'/>\n    <published>2026-02-24T04:19:48Z</published>\n    <arxiv:comment>37 pages, 8 figures, 1 table. Preprint under review. Equal contribution by first two authors</arxiv:comment>\n    <arxiv:primary_category term='cs.LG'/>\n    <author>\n      <name>Zhengyao Gu</name>\n    </author>\n    <author>\n      <name>Jonathan Light</name>\n    </author>\n    <author>\n      <name>Raul Astudillo</name>\n    </author>\n    <author>\n      <name>Ziyu Ye</name>\n    </author>\n    <author>\n      <name>Langzhou He</name>\n    </author>\n    <author>\n      <name>Henry Peng Zou</name>\n    </author>\n    <author>\n      <name>Wei Cheng</name>\n    </author>\n    <author>\n      <name>Santiago Paternain</name>\n    </author>\n    <author>\n      <name>Philip S. Yu</name>\n    </author>\n    <author>\n      <name>Yisong Yue</name>\n    </author>\n  </entry>"
}