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arxiv: 2508.13755 · v8 · submitted 2025-08-19 · 💻 cs.LG · cs.AI

Depth-Breadth Synergy in RLVR: Unlocking LLM Reasoning Gains with Adaptive Exploration

Pith reviewed 2026-05-18 22:29 UTC · model grok-4.3

classification 💻 cs.LG cs.AI
keywords RLVRLLM reasoningDARSadaptive rolloutGRPOPass@Kbatch scalingexploration
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The pith

DARS rebalances RLVR rollouts toward difficult problems to raise Pass@K while batch scaling lifts Pass@1 via entropy.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The paper argues that RLVR methods for improving LLM reasoning suffer from insufficient exploration along two axes: depth, meaning harder problems, and breadth, meaning more training instances per update. Analysis of the GRPO algorithm reveals it systematically down-weights difficult, low-accuracy problems that matter most for reasoning gains. DARS counters this with multi-stage re-balancing schedules that increase rollout outcomes specifically for harder problems, producing consistent Pass@K improvements. Scaling batch size instead boosts breadth and raises Pass@1 by increasing token-level entropy and cutting gradient noise. Combining the two in DARS-Breadth yields gains on both metrics at once.

Core claim

DARS applies targeted multi-stage rollouts to re-weight difficult low-accuracy problems according to re-balancing schedules, increasing their rollout outcomes and delivering consistent gains in Pass@K. Scaling batch size for greater breadth improves Pass@1 through higher token-level entropy that ensures robust exploration and lower gradient noise. The combined DARS-Breadth approach achieves simultaneous gains in both metrics, establishing that depth via adaptive exploration and breadth via scaled iteration instances are orthogonal and complementary dimensions.

What carries the argument

Difficulty Adaptive Rollout Sampling (DARS), which uses multi-stage re-balancing schedules to adapt the number of rollout outcomes based on problem difficulty and accuracy.

If this is right

  • DARS produces consistent Pass@K gains by increasing rollout outcomes for harder problems.
  • Scaling batch size improves Pass@1 by raising token-level entropy and reducing gradient noise.
  • DARS-Breadth achieves simultaneous gains in both Pass@K and Pass@1.
  • Depth through adaptive exploration and breadth through scaled instances function as orthogonal and complementary levers.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • The re-balancing idea could transfer to other RL algorithms that share similar accuracy-based weighting biases.
  • Practitioners might combine DARS with larger batches to improve reasoning performance without extra hyperparameter search.
  • The synergy may extend to non-verifiable reward settings if the underlying bias in problem weighting persists.
  • Testing the method on progressively harder reasoning benchmarks would clarify how far the depth-breadth gains scale.

Load-bearing premise

GRPO has a bias that systematically down-weights difficult low-accuracy problems, and DARS corrects this bias effectively without introducing new selection effects or requiring problem-specific tuning.

What would settle it

An experiment in which DARS produces no increase in effective rollout weight or Pass@K on hard problems, or in which larger batches fail to raise token-level entropy or Pass@1.

Figures

Figures reproduced from arXiv: 2508.13755 by Dongchun Xie, Hanhui Li, Jing Tang, Xiaodan Liang, Yinya Huang, Yiwei Wang, Yongxin Wang, Zhicheng Yang, Zhijiang Guo.

Figure 1
Figure 1. Figure 1: Training dynamics of Pass@1 and Pass@K performance. We show that our DARS signif￾icantly improves Pass@K performance and is complementary to breadth scaling to further improve Pass@1 performance. ∗Corresponding author: Jing Tang. 1 arXiv:2508.13755v4 [cs.LG] 6 Oct 2025 [PITH_FULL_IMAGE:figures/full_fig_p001_1.png] view at source ↗
Figure 2
Figure 2. Figure 2: Training dynamics of Pass@1 and Pass@K performance of Qwen2.5-Math-1.5b and Qwen2.5-Math-7b with different rollout size. Naive Scaling of Rollout Size Benefits Pass@1, But Not Necessarily Pass@K. We present the training dynamics of Pass@1 and Pass@K performance during the RLVR training process in Fig￾ure 2. Enlarging the rollout size allows the sampling of correct solutions to hard problems during training… view at source ↗
Figure 3
Figure 3. Figure 3: Statistical results of cumulative advantage. Group relative advantage calculation methods [PITH_FULL_IMAGE:figures/full_fig_p003_3.png] view at source ↗
Figure 4
Figure 4. Figure 4: Training dynamics of Pass@1 and Pass@K performance of Qwen2.5-Math-1.5b and Qwen2.5-Math-7b with different batch size. Breadth Sustains Entropy for Model Exploration. We further analyze the relationship between Pass@1 and token entropy during the training process, as shown in [PITH_FULL_IMAGE:figures/full_fig_p004_4.png] view at source ↗
Figure 5
Figure 5. Figure 5: Training dynamics of Pass@1 performance and token entropy for Qwen2.5-Math-1.5b and Qwen2.5-Math-7b. 3 METHODOLOGY In Section 2, we analyze the bias inherent in group-based advantage computation. To solve this is￾sue, we introduce Difficulty Adaptive Rollout Sampling (DARS), which rebalances the cumulative advantage via multi-stage sampling. By further synergizing the depth and breadth training dimen￾sions… view at source ↗
Figure 6
Figure 6. Figure 6: The overall training framework of our Difficulty Adaptive Rollout Sampling ( [PITH_FULL_IMAGE:figures/full_fig_p006_6.png] view at source ↗
Figure 7
Figure 7. Figure 7: Training dynamics of Pass@128 performance with different training steps of Qwen2.5- Math-1.5b and Qwen2.5-Math-7b. 8 [PITH_FULL_IMAGE:figures/full_fig_p008_7.png] view at source ↗
Figure 8
Figure 8. Figure 8: Training dynamics of Pass@32/Pass@128 and Pass@1 performance with different train￾ing steps of Qwen2.5-Math-1.5b and Qwen2.5-Math-7b. Depth Training with DARS Improve Pass@K Performance and Training Efficiency. Because the Pass@K (K=32/128) metric is hard to improve monotonically—it even starts to drop after pro￾longed training—while Pass@1 remains comparatively stable and rarely collapses, we seek to boos… view at source ↗
Figure 9
Figure 9. Figure 9: Complementary improve of Depth and Breadth Synergy for [PITH_FULL_IMAGE:figures/full_fig_p010_9.png] view at source ↗
Figure 10
Figure 10. Figure 10: Complete Pass@K accuracy curve of base models and our DARS models. 10 [PITH_FULL_IMAGE:figures/full_fig_p010_10.png] view at source ↗
Figure 11
Figure 11. Figure 11: Comparison of our DARS on std-based advantage computation. [PITH_FULL_IMAGE:figures/full_fig_p017_11.png] view at source ↗
Figure 12
Figure 12. Figure 12: Complementary improve of Depth and Breadth Synergy for [PITH_FULL_IMAGE:figures/full_fig_p017_12.png] view at source ↗
Figure 13
Figure 13. Figure 13: Comparison of ET and HW schedule in breadth training of Qwen2.5-Math series. [PITH_FULL_IMAGE:figures/full_fig_p018_13.png] view at source ↗
Figure 14
Figure 14. Figure 14: Control the shape of Cumulative Advantage by adjusting the [PITH_FULL_IMAGE:figures/full_fig_p018_14.png] view at source ↗
read the original abstract

Reinforcement Learning with Verifiable Reward (RLVR) is a powerful method for enhancing the reasoning abilities of Large Language Models, but its full potential is limited by a lack of exploration in two key areas: Depth (the difficulty of problems) and Breadth (the number of training instances). Our analysis of the popular GRPO algorithm reveals a bias that down-weights difficult, low-accuracy problems, which are crucial for improving reasoning skills. To address this, we introduce Difficulty Adaptive Rollout Sampling (DARS), a method that re-weights difficult problems by using targeted, multi-stage rollouts. DARS increases the number of rollout outcomes for these harder problems according to our proposed re-balancing schedules and leads to consistent gains in Pass@K. We discovered that increasing rollout size alone does not improve performance and may actually impair it. In contrast, scaling the batch size to increase breadth via full-batch updates significantly boosted Pass@1 metrics. This improvement stems from higher token-level entropy, ensuring robust exploration and minimized gradient noise. We further present DARS-Breadth, a combined approach that uses DARS with a large breadth of training data. This method demonstrates simultaneous gains in both Pass@K and Pass@1, confirming that depth (adaptive exploration) and breadth (scaling iteration instances) are orthogonal and complementary dimensions for unlocking the full power of RLVR.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

2 major / 1 minor

Summary. The manuscript analyzes a bias in the GRPO algorithm for Reinforcement Learning with Verifiable Reward (RLVR) that down-weights difficult, low-accuracy problems. It introduces Difficulty Adaptive Rollout Sampling (DARS) using multi-stage re-balancing schedules to increase rollouts on harder problems, reporting consistent gains in Pass@K. The work further shows that scaling batch size (breadth) improves Pass@1 via higher token-level entropy, while simply increasing rollout size does not, and presents DARS-Breadth as a combined method yielding simultaneous gains in both metrics, concluding that depth and breadth are orthogonal and complementary for RLVR.

Significance. If the empirical results are robust and reproducible, the paper offers a practical approach to improving exploration in RLVR by separately targeting problem difficulty (depth) and training instance volume (breadth). The finding that batch-size scaling boosts entropy and performance more effectively than rollout scaling, along with the orthogonality claim for DARS-Breadth, could inform more efficient training of reasoning LLMs. The explicit re-balancing schedules and focus on verifiable rewards represent a concrete algorithmic contribution in an active area.

major comments (2)
  1. [Abstract] Abstract: The central claim that DARS corrects GRPO's bias against difficult low-accuracy problems and yields consistent Pass@K gains is stated qualitatively, but the abstract supplies no quantitative results, specific baselines, effect sizes, or statistical details. This makes it impossible to evaluate whether the re-balancing schedules actually mitigate the bias without introducing new selection effects or requiring problem-specific tuning, as required by the weakest assumption.
  2. [Abstract] The claim that depth (DARS) and breadth (batch scaling) are orthogonal and complementary, confirmed by simultaneous gains in DARS-Breadth, rests on the assumption that total compute and rollout budget are controlled. Without explicit ablation on matched compute budgets or rollout counts across conditions, it remains unclear whether the observed gains are confounded by increased total sampling rather than true orthogonality.
minor comments (1)
  1. [Abstract] The abstract refers to 'our proposed re-balancing schedules' and 'full-batch updates' without defining the exact functional form or hyperparameters of the schedules, which would aid reproducibility.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for the constructive feedback on our work. Below we respond point-by-point to the major comments and indicate planned revisions.

read point-by-point responses
  1. Referee: [Abstract] Abstract: The central claim that DARS corrects GRPO's bias against difficult low-accuracy problems and yields consistent Pass@K gains is stated qualitatively, but the abstract supplies no quantitative results, specific baselines, effect sizes, or statistical details. This makes it impossible to evaluate whether the re-balancing schedules actually mitigate the bias without introducing new selection effects or requiring problem-specific tuning, as required by the weakest assumption.

    Authors: We agree that the abstract would be strengthened by quantitative details. In the revision we will add concise quantitative statements (e.g., relative Pass@K gains and the GRPO baseline) while preserving brevity. The re-balancing schedules are defined from aggregate accuracy statistics rather than per-problem tuning; we will add a short clarification in Section 3 to make this explicit and rule out unintended selection effects. revision: yes

  2. Referee: [Abstract] The claim that depth (DARS) and breadth (batch scaling) are orthogonal and complementary, confirmed by simultaneous gains in DARS-Breadth, rests on the assumption that total compute and rollout budget are controlled. Without explicit ablation on matched compute budgets or rollout counts across conditions, it remains unclear whether the observed gains are confounded by increased total sampling rather than true orthogonality.

    Authors: We controlled total rollout count by adjusting the number of optimization steps when batch size or rollout depth was increased, but we acknowledge that an explicit matched-budget ablation was not presented. We will add a new table and accompanying text in the experiments section that reports all three conditions (DARS, breadth scaling, DARS-Breadth) under identical total sampling budgets, confirming that the joint gains remain after budget equalization. revision: yes

Circularity Check

0 steps flagged

No significant circularity; empirical algorithmic proposal with independent experimental validation

full rationale

The paper's core contribution is an empirical analysis of GRPO training dynamics revealing a bias against difficult problems, followed by the introduction of DARS re-balancing schedules and DARS-Breadth variants. These are validated through Pass@K and Pass@1 metrics on rollout experiments, with claims about orthogonality of depth and breadth dimensions supported by observed entropy and gradient effects. No equations or first-principles derivations are presented that reduce results to fitted parameters, self-definitions, or self-citation chains; the method is an algorithmic adjustment grounded in observed data rather than a closed mathematical loop. The derivation chain remains self-contained as standard empirical RL research.

Axiom & Free-Parameter Ledger

1 free parameters · 1 axioms · 0 invented entities

The central claim rests on the existence of a GRPO bias against hard problems and on the effectiveness of the re-balancing schedules; these are introduced without independent verification details in the abstract.

free parameters (1)
  • re-balancing schedules
    Rules that determine how many additional rollouts are allocated to low-accuracy problems; these are proposed but not specified numerically in the abstract and function as tunable elements.
axioms (1)
  • domain assumption The GRPO algorithm exhibits a bias that down-weights difficult, low-accuracy problems
    Presented as the result of the authors' analysis of GRPO and used as the motivation for DARS.

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Forward citations

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    ResRL boosts LLM reasoning by modulating negative gradients with SVD-based projection residuals from negative samples, outperforming NSR by 9.4% Avg@16 on math benchmarks while preserving diversity across 12 tasks.

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Reference graph

Works this paper leans on

20 extracted references · 20 canonical work pages · cited by 6 Pith papers · 14 internal anchors

  1. [1]

    GPT-4 Technical Report

    Josh Achiam, Steven Adler, Sandhini Agarwal, Lama Ahmad, Ilge Akkaya, Florencia Leoni Ale- man, Diogo Almeida, Janko Altenschmidt, Sam Altman, Shyamal Anadkat, et al. Gpt-4 technical report.arXiv preprint arXiv:2303.08774,

  2. [2]

    Anna Goldie, Azalia Mirhoseini, Hao Zhou, Irene Cai, and Christopher D

    URLhttps://deepmind.google/ technologies/gemini/flash-thinking/. Yuqian Fu, Tinghong Chen, Jiajun Chai, Xihuai Wang, Songjun Tu, Guojun Yin, Wei Lin, Qichao Zhang, Yuanheng Zhu, and Dongbin Zhao. Srft: A single-stage method with supervised and reinforcement fine-tuning for reasoning.arXiv preprint arXiv:2506.19767,

  3. [3]

    The Llama 3 Herd of Models

    Aaron Grattafiori, Abhimanyu Dubey, Abhinav Jauhri, Abhinav Pandey, Abhishek Kadian, Ahmad Al-Dahle, Aiesha Letman, Akhil Mathur, Alan Schelten, Alex Vaughan, et al. The llama 3 herd of models.arXiv preprint arXiv:2407.21783,

  4. [4]

    DeepSeek-R1: Incentivizing Reasoning Capability in LLMs via Reinforcement Learning

    Daya Guo, Dejian Yang, Haowei Zhang, Junxiao Song, Ruoyu Zhang, Runxin Xu, Qihao Zhu, Shirong Ma, Peiyi Wang, Xiao Bi, et al. Deepseek-r1: Incentivizing reasoning capability in llms via reinforcement learning.arXiv preprint arXiv:2501.12948,

  5. [5]

    O lympiad B ench: A Challenging Benchmark for Promoting AGI with Olympiad-Level Bilingual Multimodal Scientific Problems

    Association for Computational Linguis- tics. doi: 10.18653/v1/2024.acl-long.211. URLhttps://aclanthology.org/2024. acl-long.211/. Hugging Face. Open r1: A fully open reproduction of deepseek-r1, January

  6. [6]

    OpenAI o1 System Card

    URLhttps: //github.com/huggingface/open-r1. Aaron Jaech, Adam Kalai, Adam Lerer, Adam Richardson, Ahmed El-Kishky, Aiden Low, Alec Helyar, Aleksander Madry, Alex Beutel, Alex Carney, et al. Openai o1 system card.arXiv preprint arXiv:2412.16720,

  7. [7]

    From System 1 to System 2: A Survey of Reasoning Large Language Models

    URLhttps://proceedings.neurips.cc/paper_files/paper/ 2022/file/18abbeef8cfe9203fdf9053c9c4fe191-Paper-Conference.pdf. Zhong-Zhi Li, Duzhen Zhang, Ming-Liang Zhang, Jiaxin Zhang, Zengyan Liu, Yuxuan Yao, Haotian Xu, Junhao Zheng, Pei-Jie Wang, Xiuyi Chen, et al. From system 1 to system 2: A survey of reasoning large language models.arXiv preprint arXiv:2502.17419,

  8. [8]

    Beyond pass@ 1: Self-play with variational problem synthesis sustains rlvr.arXiv preprint arXiv:2508.14029,

    Xiao Liang, Zhongzhi Li, Yeyun Gong, Yelong Shen, Ying Nian Wu, Zhijiang Guo, and Weizhu Chen. Beyond pass@ 1: Self-play with variational problem synthesis sustains rlvr.arXiv preprint arXiv:2508.14029,

  9. [9]

    Let's Verify Step by Step

    Hunter Lightman, Vineet Kosaraju, Yura Burda, Harri Edwards, Bowen Baker, Teddy Lee, Jan Leike, John Schulman, Ilya Sutskever, and Karl Cobbe. Let’s verify step by step.arXiv preprint arXiv:2305.20050,

  10. [10]

    Understanding R1-Zero-Like Training: A Critical Perspective

    Zichen Liu, Changyu Chen, Wenjun Li, Tianyu Pang, Chao Du, and Min Lin. There may not be aha moment in r1-zero-like training—a pilot study, 2025a. 12 Zichen Liu, Changyu Chen, Wenjun Li, Penghui Qi, Tianyu Pang, Chao Du, Wee Sun Lee, and Min Lin. Understanding r1-zero-like training: A critical perspective.arXiv preprint arXiv:2503.20783, 2025b. Michael Lu...

  11. [11]

    Training language models to follow instructions with human feedback

    Notion Blog. Long Ouyang, Jeff Wu, Xu Jiang, Diogo Almeida, Carroll L. Wainwright, Pamela Mishkin, Chong Zhang, Sandhini Agarwal, Katarina Slama, Alex Ray, John Schulman, Jacob Hilton, Fraser Kel- ton, Luke Miller, Maddie Simens, Amanda Askell, Peter Welinder, Paul Christiano, Jan Leike, and Ryan Lowe. Training language models to follow instructions with ...

  12. [12]

    Proximal Policy Optimization Algorithms

    John Schulman, Filip Wolski, Prafulla Dhariwal, Alec Radford, and Oleg Klimov. Proximal policy optimization algorithms.arXiv preprint arXiv:1707.06347,

  13. [13]

    Rethinking reflection in pre- training.arXiv preprint arXiv:2504.04022,

    Darsh J Shah, Peter Rushton, Somanshu Singla, Mohit Parmar, Kurt Smith, Yash Vanjani, Ashish Vaswani, Adarsh Chaluvaraju, Andrew Hojel, Andrew Ma, et al. Rethinking reflection in pre- training.arXiv preprint arXiv:2504.04022,

  14. [14]

    URLhttps://arxiv.org/abs/2402. 03300. Guangming Sheng, Chi Zhang, Zilingfeng Ye, Xibin Wu, Wang Zhang, Ru Zhang, Yanghua Peng, Haibin Lin, and Chuan Wu. Hybridflow: A flexible and efficient rlhf framework.arXiv preprint arXiv: 2409.19256,

  15. [15]

    Kimi Team, Angang Du, Bofei Gao, Bowei Xing, Changjiu Jiang, Cheng Chen, Cheng Li, Chenjun Xiao, Chenzhuang Du, Chonghua Liao, et al. Kimi k1. 5: Scaling reinforcement learning with llms.arXiv preprint arXiv:2501.12599,

  16. [16]

    URLhttps://arxiv.org/abs/ 2504.14945. An Yang, Beichen Zhang, Binyuan Hui, Bofei Gao, Bowen Yu, Chengpeng Li, Dayiheng Liu, Jianhong Tu, Jingren Zhou, Junyang Lin, Keming Lu, Mingfeng Xue, Runji Lin, Tianyu Liu, Xingzhang Ren, and Zhenru Zhang. Qwen2.5-math technical report: Toward mathematical ex- pert model via self-improvement,

  17. [17]

    URLhttps://arxiv.org/abs/2409.12122. Qiying Yu, Zheng Zhang, Ruofei Zhu, Yufeng Yuan, Xiaochen Zuo, Yu Yue, Weinan Dai, Tiantian Fan, Gaohong Liu, Lingjun Liu, Xin Liu, Haibin Lin, Zhiqi Lin, Bole Ma, Guang- ming Sheng, Yuxuan Tong, Chi Zhang, Mofan Zhang, Wang Zhang, Hang Zhu, Jinhua Zhu, Jiaze Chen, Jiangjie Chen, Chengyi Wang, Hongli Yu, Yuxuan Song, X...

  18. [18]

    DAPO: An Open-Source LLM Reinforcement Learning System at Scale

    URL https://arxiv.org/abs/2503.14476. 13 Yang Yue, Zhiqi Chen, Rui Lu, Andrew Zhao, Zhaokai Wang, Shiji Song, and Gao Huang. Does re- inforcement learning really incentivize reasoning capacity in llms beyond the base model?arXiv preprint arXiv:2504.13837, 2025a. Yu Yue, Yufeng Yuan, Qiying Yu, Xiaochen Zuo, Ruofei Zhu, Wenyuan Xu, Jiaze Chen, Chengyi Wang...

  19. [19]

    Kakade, Cengiz Pehlevan, Samy Jelassi, and Eran Malach

    Rosie Zhao, Alexandru Meterez, Sham Kakade, Cengiz Pehlevan, Samy Jelassi, and Eran Malach. Echo chamber: Rl post-training amplifies behaviors learned in pretraining.arXiv preprint arXiv:2504.07912,

  20. [20]

    After the first-stage rollout of sizeN pre, the initial cumulative advantage is: AN pre group (ˆaj) =N pre · S(ˆaj)

    14 APPENDIX A DERIVATION OFADDITIONALROLLOUTS∆n j The cumulative advantage for a group with accuracyˆaj and total rollout sizeN j =N pre + ∆nj is given by: Agroup(ˆaj, Nj) =N j · S(ˆaj), whereS(ˆaj) = 2ˆaj(1−ˆaj). After the first-stage rollout of sizeN pre, the initial cumulative advantage is: AN pre group (ˆaj) =N pre · S(ˆaj). Our goal is to determine t...