Weilu Xu
Author directory2026
Rubric-as-Experts: Case-Specific MQM Rubrics for Translation Error Span Detection
Weilu Xu | Yunzhi Shen | Xinye Wang | Renfei Dang | Shujian Huang
Findings of the Association for Computational Linguistics: EMNLP 2026
Weilu Xu | Yunzhi Shen | Xinye Wang | Renfei Dang | Shujian Huang
Findings of the Association for Computational Linguistics: EMNLP 2026
Large language models (LLMs) have shown potential for reference-free span-level translation quality estimation (QE), yet existing approaches based on Multidimensional Quality Metrics (MQM) typically rely on fixed rubric configurations shared across translation instances. However, translation instances often differ substantially in error complexity, ambiguity, and required evaluation granularity, making static rubric allocation suboptimal for span-level error detection. We find that larger MQM subtype spaces improve error coverage but also introduce more false positives, while different translation instances prefer different rubric granularities, suggesting that evaluation spaces should be allocated dynamically for each case. Therefore, we propose a case-specific dynamic rubric framework that adaptively constructs MQM evaluation spaces for individual translation instances. Unlike methods that generate fully free-form rubrics, our framework remains grounded in the predefined MQM taxonomy while dynamically selecting suitable subtype spaces and evaluation granularity for different cases. Experiments on span-level QE benchmarks from the Conference on Machine Translation (WMT) across multiple model scales demonstrate that the proposed framework consistently improves F1 and Matthews Correlation Coefficient (MCC).
Unlocking Fine-Grained Translation Quality Estimation in LRMs through Mutually Boosting Implicit and Explicit Reasoning
Renfei Dang | Xinye Wang | Zhejian Lai | Weilu Xu | Shimin Tao | Daimeng Wei | Min Zhang | Shujian Huang
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Renfei Dang | Xinye Wang | Zhejian Lai | Weilu Xu | Shimin Tao | Daimeng Wei | Min Zhang | Shujian Huang
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Large Reasoning Models (LRMs) still struggle with fine-grained translation quality estimation (QE), even with long reasoning chains. We argue that LRMs already possess strong multilingual capabilities, while the core challenge stems from the intrinsic difficulty of learning the fine-grained QE task. In this paper, we propose RIEQE (Reasoning both Implicitly and Explicitly for QE), a simple two-stage training framework that enables the mutually boosting of implicit (layer-wise) and explicit (token-wise) reasoning capabilities. To make implicit reasoning feasible, we first decompose the complex QE task into straightforward subtasks. Based on this, our two-stage approach applies: (1) NonThinking-SFT, Supervised Fine-Tuning (SFT) without reasoning chains to directly boost the model’s implicit reasoning tendency and capability; and (2) Thinking-RLVR, standard Reinforcement Learning with Verifiable Reward (RLVR) to subsequently strengthen explicit reasoning. On the WMT test sets, RIEQE based on Qwen3-4B-Thinking-2507 surpasses all baselines in explicit reasoning performance, while its implicit reasoning capability is also comparable to the best current encoder-based models. We further provide evidence for the mutually boosting between implicit and explicit reasoning, showing how they benefit each other in a bidirectional manner.
2025
基于强化学习的大语言模型古文释义选择研究
Weilu Xu | Shujian Huang
Proceedings of the 24th China National Conference on Computational Linguistics (CCL 2025)
Weilu Xu | Shujian Huang
Proceedings of the 24th China National Conference on Computational Linguistics (CCL 2025)
“古文释义选择任务对语言模型的语义理解与语境匹配能力提出了较高挑战。本文提出一种基于强化学习的训练框架,通过结果导向的奖励设计,引导大语言模型优化古文释义判断策略。实验表明,相比监督微调(Supervised Fine-tuning, SFT),强化学习方法在准确率指标上表现更优。进一步分析发现,强化学习仅在释义选择任务上的训练不仅提升了模型的古文翻译能力,还在古汉语通用能力评估基准(ACLUE)上展现出更优的跨任务迁移性。相较之下,SFT训练后的模型在翻译与其他古文任务中的表现出现明显下降。本研究为古文处理任务提供了新的训练范式,验证了强化学习在非推理类语言任务中的有效性与泛化潜力。”
LLM’s Weakness in NER Doesn’t Stop It from Enhancing a Stronger SLM
Weilu Xu | Renfei Dang | Shujian Huang
Proceedings of the Second Workshop on Ancient Language Processing
Weilu Xu | Renfei Dang | Shujian Huang
Proceedings of the Second Workshop on Ancient Language Processing
Large Language Models (LLMs) demonstrate strong semantic understanding ability and extensive knowledge, but struggle with Named Entity Recognition (NER) due to hallucination and high training costs. Meanwhile, supervised Small Language Models (SLMs) efficiently provide structured predictions but lack adaptability to unseen entities and complex contexts. In this study, we investigate how a relatively weaker LLM can effectively support a supervised model in NER tasks. We first improve the LLM using LoRA-based fine-tuning and similarity-based prompting, achieving performance comparable to a SLM baseline. To further improve results, we propose a fusion strategy that integrates both models: prioritising SLM’s predictions while using LLM guidance in low confidence cases. Our hybrid approach outperforms both baselines on three classic Chinese NER datasets.