LAQuant: A Simple Overhead-free Large Reasoning Model Quantization by Layer-wise Lookahead Loss
On the map: LLM reasoning → Test-time compute and efficient thinking
Abstract (arXiv)
Large reasoning models (LRMs) reach competition-level math and coding accuracy via long autoregressive decoding, making per-token decoding cost a primary deployment concern. Weight quantization is the standard tool for acceleration, but representative recipes -- including state-of-the-art end-to-end (E2E) QAT -- lose accuracy on long-decoding reasoning benchmarks despite preserving perplexity and short-decode accuracy. Through a systematic gradient-direction analysis, we identify two factors driving this gap: (i) KV-cache fidelity preservation under the QAT loss, which E2E supervision attenuates via the softmax Fisher metric; and (ii) Hessian-subspace alignment between calibration data and the deployment distribution. We propose LookAhead Quantization (LAQuant), a layer-wise weight-only QAT method that addresses both factors without online-transform overhead by combining reasoning-domain calibration with a one-layer lookahead loss whose implicit cross-layer co-adaptation preserves the next-layer residual stream. For Qwen3-4B under W3G128 quantization, LAQuant improves AIME25 Pass@1 over ParoQuant by 15.11pp (1.93pp over ParoQuant++ at matched calibration) while achieving a 3.42x decoding speedup over FP16 on RTX A6000, compared with ParoQuant's 3.01x.
Key facts. Cited by 1 paper in the map (data through 14 Oct 2026). Placed in Test-time compute and efficient thinking, one of 17 directions in LLM reasoning. Builds on 46 of its 56 references that are in the map. First posted on arXiv 9 May 2026.
Builds on
46 of 56 references.
Closest ancestors · 6
Same direction, newest first
- 2026QuantLRM: Quantization of Large Reasoning Models via Fine-Tuning Signals31 Jan
- 2026What Makes Low-Bit Quantization-Aware Training Work for Reasoning LLMs? A Systematic Study21 Jan
- 2025ParoQuant: Pairwise Rotation Quantization for Efficient Reasoning LLM Inference13 Nov
- 2025Quantization Hurts Reasoning? An Empirical Study on Quantized Reasoning Models7 Apr
- 2025s1: Simple test-time scaling31 Jan
- 2025Quantization Meets Reasoning: Exploring LLM Low-Bit Quantization Degradation for Mathematical Reasoning6 Jan
Other references · 40
- 2024The Llama 3 Herd of Modelscited by 14,715
- 2019Exploring the Limits of Transfer Learning with a Unified Text-to-Text Transformercited by 14,599
- 2024DeepSeekMath: Pushing the Limits of Mathematical Reasoning in Open Language Modelscited by 9,379
- 2025Qwen3 Technical Reportcited by 8,820
- 2023Efficient Memory Management for Large Language Model Serving with PagedAttentioncited by 5,944
- 2018Think you have Solved Question Answering? Try ARC, the AI2 Reasoning Challengecited by 4,886
- 2019HellaSwag: Can a Machine Really Finish Your Sentence?cited by 4,100
- 2016Pointer Sentinel Mixture Modelscited by 3,096
- 2015Fast R-CNNcited by 2,933
- 2023GPQA: A Graduate-Level Google-Proof Q&A Benchmarkcited by 2,879
- 2025DAPO: An Open-Source LLM Reinforcement Learning System at Scalecited by 2,810
- 2019BoolQ: Exploring the Surprising Difficulty of Natural Yes/No Questionscited by 2,183
28 more
- 2024LiveCodeBench: Holistic and Contamination Free Evaluation of Large Language Models for Codecited by 2,004
- 2024MMLU-Pro: A More Robust and Challenging Multi-Task Language Understanding Benchmarkcited by 1,848
- 2022SmoothQuant: Accurate and Efficient Post-Training Quantization for Large Language Modelscited by 1,386
- 2023AWQ: Activation-aware Weight Quantization for LLM Compression and Accelerationcited by 1,298
- 2024QuaRot: Outlier-Free 4-Bit Inference in Rotated LLMscited by 634
- 2024SpinQuant: LLM quantization with learned rotationscited by 471
- 2023OmniQuant: Omnidirectionally Calibrated Quantization for Large Language Modelscited by 424
- 2022Optimal Brain Compression: A Framework for Accurate Post-Training Quantization and Pruningcited by 322
- 2023SqueezeLLM: Dense-and-Sparse Quantizationcited by 294
- 2023Atom: Low-bit Quantization for Efficient and Accurate LLM Servingcited by 272
- 2024QServe: W4A8KV4 Quantization and System Co-design for Efficient LLM Servingcited by 208
- 2023BitNet: Scaling 1-bit Transformers for Large Language Modelscited by 189
- 2024RedPajama: an Open Dataset for Training Large Language Modelscited by 182
- 2024DuQuant: Distributing Outliers via Dual Transformation Makes Stronger Quantized LLMscited by 167
- 2024BiLLM: Pushing the Limit of Post-Training Quantization for LLMscited by 144
- 2024EfficientQAT: Efficient Quantization-Aware Training for Large Language Modelscited by 127
- 2024QTIP: Quantization with Trellises and Incoherence Processingcited by 91
- 2024BitDistiller: Unleashing the Potential of Sub-4-Bit LLMs via Self-Distillationcited by 84
- 2023On the Impact of Calibration Data in Post-training Quantization and Pruningcited by 58
- 2024VPTQ: Extreme Low-bit Vector Post-Training Quantization for Large Language Modelscited by 57
- 2021AR-LSAT: Investigating Analytical Reasoning of Textcited by 51
- 2024DB-LLM: Accurate Dual-Binarization for Efficient LLMscited by 37
- 2025An Empirical Study of Qwen3 Quantizationcited by 21
- 2024Layer-Wise Quantization: A Pragmatic and Effective Method for Quantizing LLMs Beyond Integer Bit-Levelscited by 16
- 2024HadaCore: Tensor Core Accelerated Hadamard Transform Kernelcited by 12
- 2025Does quantization affect models' performance on long-context tasks?cited by 10
- 2024RILQ: Rank-Insensitive LoRA-based Quantization Error Compensation for Boosting 2-bit Large Language Model Accuracycited by 9
- 2025The Impact of Quantization on Large Reasoning Model Reinforcement Learningcited by 2
Built on by
Citing papers per year: 2026: 1.
1 paper.
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