Xuchen Li
2026
MathMixup: Boosting LLM Mathematical Reasoning with Difficulty-Controllable Data Synthesis and Curriculum Learning
Xuchen Li | Jing Chen | Xuzhao Li | Hao Liang | Xiaohuan Zhou | Taifeng Wang | Wentao Zhang
Findings of the Association for Computational Linguistics: ACL 2026
Xuchen Li | Jing Chen | Xuzhao Li | Hao Liang | Xiaohuan Zhou | Taifeng Wang | Wentao Zhang
Findings of the Association for Computational Linguistics: ACL 2026
In mathematical reasoning tasks, the advancement of Large Language Models (LLMs) relies heavily on high-quality training data with clearly defined and well-graded difficulty levels. However, existing data synthesis methods often suffer from limited diversity and lack precise control over problem difficulty, making them insufficient for supporting efficient training paradigms such as curriculum learning. To address these challenges, we propose MathMixup, a novel data synthesis paradigm that systematically generates high-quality, difficulty-controllable mathematical reasoning problems through hybrid and decomposed strategies. Automated self-checking and manual screening are incorporated to ensure semantic clarity and a well-structured difficulty gradient in the synthesized data. Building on this, we construct the MathMixupQA dataset and design a curriculum learning strategy that leverages these graded problems, supporting flexible integration with other datasets. Experimental results show that MathMixup and its curriculum learning strategy significantly enhance the mathematical reasoning performance of LLMs. Fine-tuned Qwen2.5-7B achieves an average score of 52.6% across seven mathematical benchmarks, surpassing previous state-of-the-art methods. These results fully validate the effectiveness and broad applicability of MathMixup in improving the mathematical reasoning abilities of LLMs and advancing data-centric curriculum learning.
MorphoBench: A Benchmark with Difficulty Adaptive to Model Reasoning
Xukai Wang | Xuanbo Liu | Mingrui Chen | Haitian Zhong | Xuanlin Yang | Bohan Zeng | Jinbo Hu | Hao Liang | Junbo Niu | Xuchen Li | Ruitao Wu | Ruichuan An | Yang Shi | Liu Liu | Qiang Liu | Zhouchen Lin | Xu-Yao Zhang | Wentao Zhang | Bin Dong
Findings of the Association for Computational Linguistics: ACL 2026
Xukai Wang | Xuanbo Liu | Mingrui Chen | Haitian Zhong | Xuanlin Yang | Bohan Zeng | Jinbo Hu | Hao Liang | Junbo Niu | Xuchen Li | Ruitao Wu | Ruichuan An | Yang Shi | Liu Liu | Qiang Liu | Zhouchen Lin | Xu-Yao Zhang | Wentao Zhang | Bin Dong
Findings of the Association for Computational Linguistics: ACL 2026
With the advancement of powerful large-scale reasoning models, effectively evaluating the reasoning capabilities of these models has become increasingly important. However, existing benchmarks designed to assess the reasoning abilities of large models tend to be limited in scope and lack the flexibility to adapt their difficulty according to the evolving reasoning capacities of the models. To address this, we propose MorphoBench, a benchmark that incorporates multidisciplinary questions to evaluate the reasoning capabilities of large models and can adjust and update question difficulty based on the reasoning abilities of advanced models. Specifically, we curate the benchmark by selecting and collecting complex reasoning questions from existing benchmarks and sources such as Olympiad-level competitions. Additionally, MorphoBench adaptively modifies the analytical challenge of questions by leveraging key statements generated during the model’s reasoning process. Furthermore, it includes questions generated using simulation software, enabling dynamic adjustment of benchmark difficulty with minimal resource consumption. We have gathered over 1,300 test questions and iteratively adjusted the difficulty of MorphoBench based on the reasoning capabilities of models such as GPT-5 and Gemini-3-Pro. MorphoBench enhances the comprehensiveness and validity of model reasoning evaluation, providing reliable guidance for improving both the reasoning abilities and scientific robustness of large models.
Look Less, Reason More: Rollout-Guided Adaptive Pixel-Space Reasoning
Xuchen Li | Xuzhao Li | Jiahui Gao | Renjie Pi | Shiyu Hu | Wentao Zhang
Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)
Xuchen Li | Xuzhao Li | Jiahui Gao | Renjie Pi | Shiyu Hu | Wentao Zhang
Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)
Vision-Language Models (VLMs) excel at many multimodal tasks, yet they frequently struggle with tasks requiring precise understanding and handling of fine-grained visual elements. This is mainly due to information loss during image encoding or insufficient attention to critical regions. Recent work has shown promise by incorporating pixel-level visual information into the reasoning process, enabling VLMs to access high-resolution visual details during their thought process. However, this pixel-level information is often overused, leading to inefficiency and distraction from irrelevant visual details. To address these challenges, we propose the first framework for adaptive pixel reasoning that dynamically determines necessary pixel-level operations based on the input query. Specifically, we first apply operation-aware supervised fine-tuning to establish baseline competence in textual reasoning and visual operations, then design a novel rollout-guided reinforcement learning framework relying on feedback of the model’s own responses, which enables the VLM to determine when pixel operations should be invoked based on query difficulty. Experiments on extensive multimodal reasoning benchmarks show that our model achieves superior performance while significantly reducing unnecessary visual operations. Impressively, our model achieves 73.4% accuracy on HR-Bench 4K while maintaining a tool usage ratio of only 20.1%, improving accuracy and simultaneously reducing tool usage by 66.5% compared to the previous methods.