Stabilizing Unsupervised Self-Evolution of MLLMs via Continuous Softened Retracing reSampling

Yunyao Yu, ZhengXian Wu, Zhuohong Chen, Hangrui Xu, Zirui Liao, Xiangwen Deng, Zhifang Liu, Senyuan Shi, Haoqian Wang


Abstract
In the unsupervised self-evolution of Multimodal Large Language Models, the quality of feedback signals during post-training is pivotal for stable and effective learning. However, existing self-evolution methods predominantly rely on majority voting to select the most frequent output as the pseudo-golden answer, which may stem from the model’s intrinsic biases rather than guaranteeing the objective correctness of the reasoning paths. To counteract the degradation, we propose Continuous Softened Retracing reSampling (CSRS) in MLLM self-evolution. Specifically, we introduce a Retracing Re-inference Mechanism (RRM) that the model re-inferences from anchor points to expand the exploration of long-tail reasoning paths. Simultaneously, we propose Softened Frequency Reward (SFR), which replaces binary rewards with continuous signals, calibrating reward based on the answers’ frequency across sampled reasoning sets. Furthermore, incorporated with Visual Semantic Perturbation (VSP), CSRS ensures the model prioritizes mathematical logic over visual superficiality. Experimental results demonstrate that CSRS significantly enhances the reasoning performance of Qwen2.5-VL-7B on benchmarks such as MathVision. We achieve state-of-the-art (SOTA) results in unsupervised self-evolution on geometric tasks.
Anthology ID:
2026.emnlp-main.199
Volume:
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Month:
October
Year:
2026
Address:
Budapest, Hungary
Editors:
Hung-Yi Lee, Sunipa Dev, Jessy Li, Desmond Elliott
Venue:
EMNLP
SIG:
SIGDAT
Publisher:
Association for Computational Linguistics
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Pages:
4555–4571
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URL:
https://aclanthology.org/2026.emnlp-main.199/
DOI:
Bibkey:
Cite (ACL):
Yunyao Yu, ZhengXian Wu, Zhuohong Chen, Hangrui Xu, Zirui Liao, Xiangwen Deng, Zhifang Liu, Senyuan Shi, and Haoqian Wang. 2026. Stabilizing Unsupervised Self-Evolution of MLLMs via Continuous Softened Retracing reSampling. In Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing, pages 4555–4571, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
Stabilizing Unsupervised Self-Evolution of MLLMs via Continuous Softened Retracing reSampling (Yu et al., EMNLP 2026)
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https://aclanthology.org/2026.emnlp-main.199.pdf