@inproceedings{yang-etal-2025-ad,
    title = "{AD}-{LLM}: Benchmarking Large Language Models for Anomaly Detection",
    author = "Yang, Tiankai  and
      Nian, Yi  and
      Li, Li  and
      Xu, Ruiyao  and
      Li, Yuangang  and
      Li, Jiaqi  and
      Xiao, Zhuo  and
      Hu, Xiyang  and
      Rossi, Ryan A.  and
      Ding, Kaize  and
      Hu, Xia  and
      Zhao, Yue",
    editor = "Che, Wanxiang  and
      Nabende, Joyce  and
      Shutova, Ekaterina  and
      Pilehvar, Mohammad Taher",
    booktitle = "Findings of the Association for Computational Linguistics: ACL 2025",
    month = jul,
    year = "2025",
    address = "Vienna, Austria",
    publisher = "Association for Computational Linguistics",
    url = "https://preview.aclanthology.org/corrections-2025-08/2025.findings-acl.79/",
    doi = "10.18653/v1/2025.findings-acl.79",
    pages = "1524--1547",
    ISBN = "979-8-89176-256-5",
    abstract = "Anomaly detection (AD) is an important machine learning task with many real-world uses, including fraud detection, medical diagnosis, and industrial monitoring. Within natural language processing (NLP), AD helps detect issues like spam, misinformation, and unusual user activity. Although large language models (LLMs) have had a strong impact on tasks such as text generation and summarization, their potential in AD has not been studied enough. This paper introduces AD-LLM, the first benchmark that evaluates how LLMs can help with NLP anomaly detection. We examine three key tasks: (i) zero-shot detection, using LLMs' pre-trained knowledge to perform AD without tasks-specific training; (ii) data augmentation, generating synthetic data and category descriptions to improve AD models; and (iii) model selection, using LLMs to suggest unsupervised AD models. Through experiments with different datasets, we find that LLMs can work well in zero-shot AD, that carefully designed augmentation methods are useful, and that explaining model selection for specific datasets remains challenging. Based on these results, we outline six future research directions on LLMs for AD."
}