An Wang
Author directoryPapers on this page may belong to the following people: An Wang, An Wang
2026
Beyond Token Positions: Safety Alignment Across Denoising Steps in Diffusion Language Models
Guoli Wang | Haonan Shi | Tu Ouyang | An Wang
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Guoli Wang | Haonan Shi | Tu Ouyang | An Wang
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Diffusion large language models (dLLMs) generate text through iterative denoising rather than left-to-right decoding. This generation paradigm introduces two axes that can influence safety alignment: when tokens are generated during denoising and where they appear in the response. In this paper, we measure dLLM safety behavior under harmful prompts by tracing intermediate token distributions and commitment decisions throughout denoising. Our analysis shows that refusal signals are concentrated in early denoising steps and leading response positions, and the tokens committed early can strongly shape the final safety outcome. Our measurements further show that the denoising step and persistence of refusal-token commitment are important for understanding dLLM safety. Based on these findings, we propose Refusal-Aware Early Commitment (RAEC), a simple training-free decoding method that commits persistent refusal signals from early steps. Experiments on LLaDA and Dream show that RAEC reduces attack success rates while largely preserving utility. The code is available at https://github.com/Glresearch1/RAEC.
2024
Building a Japanese Document-Level Relation Extraction Dataset Assisted by Cross-Lingual Transfer
Youmi Ma | An Wang | Naoaki Okazaki
Proceedings of the 2024 Joint International Conference on Computational Linguistics, Language Resources and Evaluation (LREC-COLING 2024)
Youmi Ma | An Wang | Naoaki Okazaki
Proceedings of the 2024 Joint International Conference on Computational Linguistics, Language Resources and Evaluation (LREC-COLING 2024)
Document-level Relation Extraction (DocRE) is the task of extracting all semantic relationships from a document. While studies have been conducted on English DocRE, limited attention has been given to DocRE in non-English languages. This work delves into effectively utilizing existing English resources to promote DocRE studies in non-English languages, with Japanese as the representative case. As an initial attempt, we construct a dataset by transferring an English dataset to Japanese. However, models trained on such a dataset are observed to suffer from low recalls. We investigate the error cases and attribute the failure to different surface structures and semantics of documents translated from English and those written by native speakers. We thus switch to explore if the transferred dataset can assist human annotation on Japanese documents. In our proposal, annotators edit relation predictions from a model trained on the transferred dataset. Quantitative analysis shows that relation recommendations suggested by the model help reduce approximately 50% of the human edit steps compared with the previous approach. Experiments quantify the performance of existing DocRE models on our collected dataset, portraying the challenges of Japanese and cross-lingual DocRE.
2023
Generative Data Augmentation for Aspect Sentiment Quad Prediction
An Wang | Junfeng Jiang | Youmi Ma | Ao Liu | Naoaki Okazaki
Proceedings of the 12th Joint Conference on Lexical and Computational Semantics (*SEM 2023)
An Wang | Junfeng Jiang | Youmi Ma | Ao Liu | Naoaki Okazaki
Proceedings of the 12th Joint Conference on Lexical and Computational Semantics (*SEM 2023)
Aspect sentiment quad prediction (ASQP) analyzes the aspect terms, opinion terms, sentiment polarity, and aspect categories in a text. One challenge in this task is the scarcity of data owing to the high annotation cost. Data augmentation techniques are commonly used to address this issue. However, existing approaches simply rewrite texts in the training data, restricting the semantic diversity of the generated data and impairing the quality due to the inconsistency between text and quads. To address these limitations, we augment quads and train a quads-to-text model to generate corresponding texts. Furthermore, we designed novel strategies to filter out low-quality data and balance the sample difficulty distribution of the augmented dataset. Empirical studies on two ASQP datasets demonstrate that our method outperforms other data augmentation methods and achieves state-of-the-art performance on the benchmarks. The source code will be released upon acceptance.
DREEAM: Guiding Attention with Evidence for Improving Document-Level Relation Extraction
Youmi Ma | An Wang | Naoaki Okazaki
Proceedings of the 17th Conference of the European Chapter of the Association for Computational Linguistics
Youmi Ma | An Wang | Naoaki Okazaki
Proceedings of the 17th Conference of the European Chapter of the Association for Computational Linguistics
Document-level relation extraction (DocRE) is the task of identifying all relations between each entity pair in a document. Evidence, defined as sentences containing clues for the relationship between an entity pair, has been shown to help DocRE systems focus on relevant texts, thus improving relation extraction. However, evidence retrieval (ER) in DocRE faces two major issues: high memory consumption and limited availability of annotations. This work aims at addressing these issues to improve the usage of ER in DocRE. First, we propose DREEAM, a memory-efficient approach that adopts evidence information as the supervisory signal, thereby guiding the attention modules of the DocRE system to assign high weights to evidence. Second, we propose a self-training strategy for DREEAM to learn ER from automatically-generated evidence on massive data without evidence annotations. Experimental results reveal that our approach exhibits state-of-the-art performance on the DocRED benchmark for both DocRE and ER. To the best of our knowledge, DREEAM is the first approach to employ ER self-training.
2021
Attention-based Relational Graph Convolutional Network for Target-Oriented Opinion Words Extraction
Junfeng Jiang | An Wang | Akiko Aizawa
Proceedings of the 16th Conference of the European Chapter of the Association for Computational Linguistics: Main Volume
Junfeng Jiang | An Wang | Akiko Aizawa
Proceedings of the 16th Conference of the European Chapter of the Association for Computational Linguistics: Main Volume
Target-oriented opinion words extraction (TOWE) is a subtask of aspect-based sentiment analysis (ABSA). It aims to extract the corresponding opinion words for a given opinion target in a review sentence. Intuitively, the relation between an opinion target and an opinion word mostly relies on syntactics. In this study, we design a directed syntactic dependency graph based on a dependency tree to establish a path from the target to candidate opinions. Subsequently, we propose a novel attention-based relational graph convolutional neural network (ARGCN) to exploit syntactic information over dependency graphs. Moreover, to explicitly extract the corresponding opinion words toward the given opinion target, we effectively encode target information in our model with the target-aware representation. Empirical results demonstrate that our model significantly outperforms all of the existing models on four benchmark datasets. Extensive analysis also demonstrates the effectiveness of each component of our models. Our code is available at https://github.com/wcwowwwww/towe-eacl.