Papers › AD-LLM: Benchmarking Large Language Models for Anomaly Detection

AD-LLM: Benchmarking Large Language Models for Anomaly Detection

15 Dec 2024arXiv:2412.11142archive 2025-07-28

Tiankai Yang, Yi Nian, Shawn Li, Ruiyao Xu, Yuangang Li, Jiaqi Li, Zhuo Xiao, Xiyang Hu, Ryan Rossi, Kaize Ding, Xia Hu, Yue Zhao

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.

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generate_embeddings usc-fortis/ad-llm/baseline_w_gpt_embed.py official repository unverified MIT (permissive) · b45367566abc496b · report
generate_prompt_setting_1 usc-fortis/ad-llm/prompt/ad_1_gpt_prompt.py official repository unverified MIT (permissive) · 141469aa23018895 · report
generate_prompt_setting_1 usc-fortis/ad-llm/prompt/ad_1_llama_prompt.py official repository unverified MIT (permissive) · 8aa0ff2182ce2c41 · report
generate_prompt_setting_2 usc-fortis/ad-llm/prompt/ad_2_gpt_prompt.py official repository unverified MIT (permissive) · d781fa3b578a72e3 · report
read_data_summary usc-fortis/ad-llm/utils.py official repository unverified MIT (permissive) · 8350c5663464101b · report
read_json usc-fortis/ad-llm/utils.py official repository unverified MIT (permissive) · 772778f25f3bd45f · report
read_normal_desc usc-fortis/ad-llm/utils.py official repository unverified MIT (permissive) · abc3be5d5ec0f373 · report

Tasks

Anomaly DetectionBenchmarkingData AugmentationFraud DetectionMedical DiagnosisMisinformationModel SelectionText Generation

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