Weinan Zhang
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Unverified author pages with similar names: Weinan Zhang
2026
FAER: Benchmarking VLMs for Failure-Aware Embodied Reasoning
Hao Song | Kaifeng Liu | Yuanxing Liu | Xiang Tian | Xuesong Wang | Chen Yifan | Weinan Zhang | Ting Liu
Findings of the Association for Computational Linguistics: ACL 2026
Hao Song | Kaifeng Liu | Yuanxing Liu | Xiang Tian | Xuesong Wang | Chen Yifan | Weinan Zhang | Ting Liu
Findings of the Association for Computational Linguistics: ACL 2026
Failures are inevitable when embodied agents execute complex tasks. Visual-language models (VLMs) serve as the core component of embodied agents in perceiving the environment and making decisions. Assessing the capabilities of VLMs in detecting and reasoning about failures has become increasingly important. Previous work primarily considered low-level manipulation failures (e.g., 3cm grasp offsets), neglecting high-level failures arising during long-horizon task execution (e.g., object-dropping failure in the “clean room” task) by embodied agents. In this paper, we propose FAER, a failure-aware benchmark aiming to evaluate the performance of VLMs in terms of failure detection, failure categorization, failure description, and failure correction in long-horizon tasks. FAER comprises 3,323 episodes, spanning 3 scenes, 65 tasks, and 83 objects. We assess the performance of 16 widely utilized VLMs and 4 LLMs for FAER tasks. Experimental results show that nearly all VLMs, even GPT-4o, exhibit limited performance in failure detection with a high false negative rate, meaning that they tend to ignore abnormal events, revealing notable gaps in current models’ capacity to effectively handle failures.
Exploring and Distilling Multi-Dimensional Clues for Interpretable Social Bot Detection
Yi Han | Haiqi Lu | Lizi Liao | Shuhan Zhou | Yuanxing Liu | Weinan Zhang | Ting Liu
Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)
Yi Han | Haiqi Lu | Lizi Liao | Shuhan Zhou | Yuanxing Liu | Weinan Zhang | Ting Liu
Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)
Social bot accounts have long been disseminating disinformation and engaging in malicious activities on social media platforms. Detecting these social bots has become a critical and urgent task, essential for maintaining a healthy online ecosystem. Existing social bot detection research usually provides detection results directly without corresponding supportive explanations, making it difficult to assess the extent to which such predictions are trustworthy. This is a key concern for online moderation. In this work, we explore the detection interpretation and summarize a four-dimensional clue framework from individual and social perspectives. We propose CDRBot, which primarily employs outcome-reward reinforcement learning to train inspectors to generate faithful, grounded, and readable clues from the User Information, Semantic Features, Interactive Situation, and Behavioral Pattern. These clues are then integrated to make final predictions. Experimental results demonstrate that our approach outperforms other baselines in detection performance. The generated clues are faithful, grounded, and readable, and can significantly enhance the performance of large language models in social bot detection.
2025
Stimulate the Critical Thinking of LLMs via Debiasing Discussion
Ruiyu Xiao | Lei Wu | Yuanxing Liu | Weinan Zhang | Ting Liu
Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing
Ruiyu Xiao | Lei Wu | Yuanxing Liu | Weinan Zhang | Ting Liu
Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing
Large language models (LLMs) often succumb to users’ viewpoints when faced with conflicting perspectives. We identify two key biases underlying this issue : stance homogeneity bias and human preference bias. To address these biases, we propose a novel two-stage training framework: Multi-stance Discussion Sampling and Truth Alignment Training (MDTA). First, we introduce an equal multi-stance discussion framework to automatically generate multi-model discussion datasets. Based on this framework, we construct the first and largest multi-model fair discussion dataset named Eq-Discussion for supervised fine-tuning, reducing stance homogeneity bias. Second, we optimize Reinforcement Learning from Human Feedback (RLHF) to align with discussion correctness, mitigating human preference bias. Extensive experimental results demonstrate that MDTA effectively reduces both biases and significantly enhances the performance of LLMs across a variety of downstream tasks, including reading comprehension, logical reasoning, and social question answering. Furthermore, we observe that MDTA improves the generalization capabilities of LLMs, leading to substantial performance improvements in non-discussion scenarios and on out-of-domain datasets.
Nullspace Disentanglement for Red Teaming Language Models
Yi Han | Yuanxing Liu | Weinan Zhang | Ting Liu
Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing
Yi Han | Yuanxing Liu | Weinan Zhang | Ting Liu
Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing
With the widespread deployment of generative language models, concerns about safety issues have continuously grown. High-quality fine-tuning data generated from red teaming plays a crucial role in the model’s safety. Recently, automated red teaming approaches have been proposed to create test cases. However, these approaches, which rely on open-ended generation, encounter issues related to inefficiency and low attack success rates. In this work, we introduce a black-box approach that ingeniously exploits the unique properties of the nullspace to disentangle and regulate the crucial success information within test cases. Our study provides a brand-new perspective for automated red team research. Experimental results demonstrate that our approach outperforms baseline methods regarding the attack success rate. The generated test cases also excel in aspects of diversity and fluency.
2024
Unraveling and Mitigating Retriever Inconsistencies in Retrieval-Augmented Large Language Models
Mingda Li | Xinyu Li | Yifan Chen | Wenfeng Xuan | Weinan Zhang
Findings of the Association for Computational Linguistics: ACL 2024
Mingda Li | Xinyu Li | Yifan Chen | Wenfeng Xuan | Weinan Zhang
Findings of the Association for Computational Linguistics: ACL 2024
Although Retrieval-Augmented Large Language Models (RALMs) demonstrate their superiority in terms of factuality, they do not consistently outperform the original retrieval-free Language Models (LMs). Our experiments reveal that this example-level performance inconsistency exists not only between retrieval-augmented and retrieval-free LM but also among different retrievers. To understand this phenomenon, we investigate the degeneration behavior of RALMs and theoretically decompose it into four categories. Further analysis based on our decomposition reveals that the innate difference in knowledge sources and the unpredictable degeneration of the reader model contribute most to the inconsistency. Drawing from our analysis, we introduce Ensemble of Retrievers (EoR), a trainable framework that can adaptively retrieve from different knowledge sources and effectively decrease unpredictable reader errors. Our experiments on Open Domain Question Answering show that EoR substantially improves performance over the RALM with a single retriever by considerably reducing inconsistent behaviors.
Prove Your Point!: Bringing Proof-Enhancement Principles to Argumentative Essay Generation
Ruiyu Xiao | Lei Wu | Yuhang Gou | Weinan Zhang | Ting Liu
Proceedings of the 2024 Conference on Empirical Methods in Natural Language Processing
Ruiyu Xiao | Lei Wu | Yuhang Gou | Weinan Zhang | Ting Liu
Proceedings of the 2024 Conference on Empirical Methods in Natural Language Processing
Argumentative essay generation (AEG) aims to generate complete texts on specific controversial topics or debates. Although current AEG methods can generate individual opinions, they often overlook the high-level connections between these opinions. This often leads to the generated results being mired in logical confusion, unable to proof their own arguments effectively. The generated essay may present evidence that contradicts the claims or they may fail to assemble the claims into logical flow. In this paper, we present a unified two-stage framework: Proof-Enhancement and Self-Annotation (PESA) for AEG with a focus on logical enhancement. Specifically, we first construct pseudo-labels for logical information,claims and grounds, using a large language model. We then propose a tree planning approach that introduces proof principles and ensures logical consistency. Extensive experimental results show that, benefiting from proof principle guidance, PESA generates argumentative essays with better logical validity and persuasiveness than strong baseline models.
2022
CLIP Models are Few-Shot Learners: Empirical Studies on VQA and Visual Entailment
Haoyu Song | Li Dong | Weinan Zhang | Ting Liu | Furu Wei
Proceedings of the 60th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)
Haoyu Song | Li Dong | Weinan Zhang | Ting Liu | Furu Wei
Proceedings of the 60th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)
CLIP has shown a remarkable zero-shot capability on a wide range of vision tasks. Previously, CLIP is only regarded as a powerful visual encoder. However, after being pre-trained by language supervision from a large amount of image-caption pairs, CLIP itself should also have acquired some few-shot abilities for vision-language tasks. In this work, we empirically show that CLIP can be a strong vision-language few-shot learner by leveraging the power of language. We first evaluate CLIP’s zero-shot performance on a typical visual question answering task and demonstrate a zero-shot cross-modality transfer capability of CLIP on the visual entailment task. Then we propose a parameter-efficient fine-tuning strategy to boost the few-shot performance on the vqa task. We achieve competitive zero/few-shot results on the visual question answering and visual entailment tasks without introducing any additional pre-training procedure.