Fangning Chao
Author directory2026
FlipTS: Failure-to-Success Mathematical Self-Refinement via Trajectory-Aware Sampling in End-to-End Online RL
Yaqian Hao | Yifan Hao | Yankai Liu | Fangning Chao | Zhaojun Cui | Haiyu Zhang | Huan Bai | Fanyu Meng | Chao Deng | Junlan Feng
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Yaqian Hao | Yifan Hao | Yankai Liu | Fangning Chao | Zhaojun Cui | Haiyu Zhang | Huan Bai | Fanyu Meng | Chao Deng | Junlan Feng
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Self-Refinement has emerged as a promising paradigm for improving Large Language Model (LLM) performance by iteratively improving its response at inference time. Existing training methods typically treat refinement as a decoupled task and rely on pre-generated responses, thereby detaching training from the model’s actual reasoning trajectories and hindering performance. In this paper, we propose FlipTS (Failure-to-Success Learning for self-refinement with Potential-guided Trajectory-Aware Sampling), an end-to-end reinforcement learning (RL) framework that optimizes the entire self-refinement loop online. We identify a fundamental bottleneck in this end-to-end setting: the sparsity of informative refinement behaviors Failure-to-Success (F2S). FlipTS addresses this by utilizing a non-stationary Bayesian model to estimate data potential and applying trajectory-aware sampling to enrich the training process with valuable refinement signals. Experiments on Qwen3-4B-Instruct, Qwen3-1.7B and LLaMA-3.1-8B-Instruct across challenging mathematical benchmarks demonstrate that FlipTS consistently outperforms both offline and online RL baselines. Notably, it exhibits robust generalization to factuality, scientific reasoning and legal reasoning tasks without domain-specific tuning. Our code will be open-sourced.