What makes Reasoning Models Different? Follow the Reasoning Leader for Efficient Decoding
- URL: http://arxiv.org/abs/2506.06998v1
- Date: Sun, 08 Jun 2025 05:08:32 GMT
- Title: What makes Reasoning Models Different? Follow the Reasoning Leader for Efficient Decoding
- Authors: Ming Li, Zhengyuan Yang, Xiyao Wang, Dianqi Li, Kevin Lin, Tianyi Zhou, Lijuan Wang,
- Abstract summary: We analyze the token-level misalignment between reasoning and non-reasoning models.<n>Motivated by the Local Misalignment Diminish, we propose FoReaL-Decoding.<n>On four popular math-reasoning benchmarks, FoReaL-Decoding reduces theoretical FLOPs by 30 to 50% and trims CoT length by up to 40%.
- Score: 84.42056293290015
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Large reasoning models (LRMs) achieve strong reasoning performance by emitting long chains of thought. Yet, these verbose traces slow down inference and often drift into unnecessary detail, known as the overthinking phenomenon. To better understand LRMs' behavior, we systematically analyze the token-level misalignment between reasoning and non-reasoning models. While it is expected that their primary difference lies in the stylistic "thinking cues", LRMs uniquely exhibit two pivotal, previously under-explored phenomena: a Global Misalignment Rebound, where their divergence from non-reasoning models persists or even grows as response length increases, and more critically, a Local Misalignment Diminish, where the misalignment concentrates at the "thinking cues" each sentence starts with but rapidly declines in the remaining of the sentence. Motivated by the Local Misalignment Diminish, we propose FoReaL-Decoding, a collaborative fast-slow thinking decoding method for cost-quality trade-off. In FoReaL-Decoding, a Leading model leads the first few tokens for each sentence, and then a weaker draft model completes the following tokens to the end of each sentence. FoReaL-Decoding adopts a stochastic gate to smoothly interpolate between the small and the large model. On four popular math-reasoning benchmarks (AIME24, GPQA-Diamond, MATH500, AMC23), FoReaL-Decoding reduces theoretical FLOPs by 30 to 50% and trims CoT length by up to 40%, while preserving 86 to 100% of model performance. These results establish FoReaL-Decoding as a simple, plug-and-play route to controllable cost-quality trade-offs in reasoning-centric tasks.
Related papers
- Accelerating LLM Reasoning via Early Rejection with Partial Reward Modeling [12.835376812101323]
We introduce the hypothesis that PRMs are also Partial Reward Models.<n>This allows for principled early rejection based on intermediate token-level signals.<n>On math reasoning benchmarks, our method achieves up to 1.4$times$-9$times$ reduction in inference FLOPs without degrading final performance.
arXiv Detail & Related papers (2025-08-04T00:58:56Z) - R-Stitch: Dynamic Trajectory Stitching for Efficient Reasoning [60.37610817226533]
Chain-of-thought (CoT) reasoning encourages step-by-step intermediate reasoning during inference.<n>CoT introduces substantial computational overhead due to its reliance on autoregressive decoding over long token sequences.<n>We present R-Stitch, a token-level, confidence-based hybrid decoding framework that accelerates CoT inference.
arXiv Detail & Related papers (2025-07-23T08:14:36Z) - CoThink: Token-Efficient Reasoning via Instruct Models Guiding Reasoning Models [56.40065909544213]
Large language models (LLMs) benefit from increased test-time compute, a phenomenon known as test-time scaling.<n>However, reasoning-optimized models often overthink even simple problems, producing excessively verbose outputs and leading to low token efficiency.<n>We identify two key causes of this verbosity: (1) reinforcement learning reduces the information density of forward reasoning, and (2) backward chain-of thought training encourages redundant and often unnecessary verification steps.
arXiv Detail & Related papers (2025-05-28T06:24:45Z) - Done Is Better than Perfect: Unlocking Efficient Reasoning by Structured Multi-Turn Decomposition [11.858707687894757]
Large Reasoning Models (LRMs) are criticized for the excessively lengthy Chain-of-Thought (CoT) to derive the final answer.<n>This paper introduces Multi-Turn Decomposition (MinD) to decode conventional CoT into a sequence of explicit, structured, and turn-wise interactions.<n>MinD can achieve up to 70% reduction in both output token usage and time to first token (TTFT)
arXiv Detail & Related papers (2025-05-26T10:18:57Z) - Think-RM: Enabling Long-Horizon Reasoning in Generative Reward Models [50.4652276723694]
Think-RM generates flexible, self-guided reasoning traces that support advanced capabilities.<n>Think-RM achieves state-of-the-art results on RM-Bench, outperforming both BT RM and vertically scaled GenRM by 8%.
arXiv Detail & Related papers (2025-05-22T05:56:11Z) - R-TOFU: Unlearning in Large Reasoning Models [5.116399056871577]
We introduce Reasoning-TOFU, the first benchmark tailored to this setting.<n>R-TOFU augments existing unlearning tasks with realistic CoT annotations.<n>We propose Reasoned IDK, a preference-optimization variant that preserves coherent yet inconclusive reasoning.
arXiv Detail & Related papers (2025-05-21T07:44:30Z) - Let LLMs Break Free from Overthinking via Self-Braking Tuning [60.08396797526657]
Large reasoning models (LRMs) have significantly enhanced their reasoning capabilities by generating longer chains of thought.<n>This performance gain comes at the cost of a substantial increase in redundant reasoning during the generation process.<n>We propose a novel framework, Self-Braking Tuning (SBT), which tackles overthinking from the perspective of allowing the model to regulate its own reasoning process.
arXiv Detail & Related papers (2025-05-20T16:53:40Z) - Fractured Chain-of-Thought Reasoning [61.647243580650446]
We introduce Fractured Sampling, a unified inference-time strategy that interpolates between full CoT and solution-only sampling.<n>We show that Fractured Sampling consistently achieves superior accuracy-cost trade-offs, yielding steep log-linear scaling gains in Pass@k versus token budget.
arXiv Detail & Related papers (2025-05-19T11:30:41Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.