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Related papers: Is Training Necessary for Anomaly Detection?

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We introduce a new semi-supervised, time series anomaly detection algorithm that uses deep reinforcement learning (DRL) and active learning to efficiently learn and adapt to anomalies in real-world time series data. Our model - called RLAD…

Machine Learning · Computer Science 2021-04-02 Tong Wu , Jorge Ortiz

Classification algorithms have been widely adopted to detect anomalies for various systems, e.g., IoT, cloud and face recognition, under the common assumption that the data source is clean, i.e., features and labels are correctly set.…

Machine Learning · Computer Science 2019-11-12 Zilong Zhao , Robert Birke , Rui Han , Bogdan Robu , Sara Bouchenak , Sonia Ben Mokhtar , Lydia Y. Chen

Classification algorithms have been widely adopted to detect anomalies for various systems, e.g., IoT, cloud and face recognition, under the common assumption that the data source is clean, i.e., features and labels are correctly set.…

Machine Learning · Computer Science 2021-03-22 Zilong Zhao , Robert Birke , Rui Han , Bogdan Robu , Sara Bouchenak , Sonia Ben Mokhtar , Lydia Y. Chen

This paper explores the problem of class-agnostic anomaly detection (AD), where the objective is to train one class-agnostic AD model that can generalize to detect anomalies in diverse new classes from different domains without any…

Computer Vision and Pattern Recognition · Computer Science 2025-09-30 Xincheng Yao , Chao Shi , Muming Zhao , Guangtao Zhai , Chongyang Zhang

Conventional unsupervised anomaly detection (UAD) methods build separate models for each object category. Recent studies have proposed to train a unified model for multiple classes, namely model-unified UAD. However, such methods still…

Computer Vision and Pattern Recognition · Computer Science 2024-04-17 Jia Guo , Haonan Han , Shuai Lu , Weihang Zhang , Huiqi Li

Anomaly detection (AD) is the machine learning task of identifying highly discrepant abnormal samples by solely relying on the consistency of the normal training samples. Under the constraints of a distribution shift, the assumption that…

Machine Learning · Computer Science 2023-12-25 João B. S. Carvalho , Mengtao Zhang , Robin Geyer , Carlos Cotrini , Joachim M. Buhmann

In practice, machine learning methods commonly require anomaly detection (AD) to filter inputs or detect distributional shifts. Typically, this is implemented by running a separate AD model alongside the primary model. However, this…

Machine Learning · Computer Science 2026-03-19 Luca Hinkamp , Simon Klüttermann , Emmanuel Müller

Unsupervised GAD methods assume the lack of anomaly labels, i.e., whether a node is anomalous or not. One common observation we made from previous unsupervised methods is that they not only assume the absence of such anomaly labels, but…

Machine Learning · Computer Science 2023-08-24 Junghoon Kim , Yeonjun In , Kanghoon Yoon , Junmo Lee , Chanyoung Park

This paper explores the problem of Generalist Anomaly Detection (GAD), aiming to train one single detection model that can generalize to detect anomalies in diverse datasets from different application domains without any further training on…

Computer Vision and Pattern Recognition · Computer Science 2024-03-19 Jiawen Zhu , Guansong Pang

Unsupervised anomaly detection (UAD) is a widely adopted approach in industry due to rare anomaly occurrences and data imbalance. A desirable characteristic of an UAD model is contained generalization ability which excels in the…

Computer Vision and Pattern Recognition · Computer Science 2023-08-29 YeongHyeon Park , Sungho Kang , Myung Jin Kim , Hyeonho Jeong , Hyunkyu Park , Hyeong Seok Kim , Juneho Yi

Deep anomaly detection models using a supervised mode of learning usually work under a closed set assumption and suffer from overfitting to previously seen rare anomalies at training, which hinders their applicability in a real scenario. In…

Image and Video Processing · Electrical Eng. & Systems 2020-10-26 Behzad Bozorgtabar , Dwarikanath Mahapatra , Guillaume Vray , Jean-Philippe Thiran

This paper introduces GRAD, a real-time anomaly detection method for autonomous vehicle sensors that integrates statistical analysis and deep learning to ensure the reliability of sensor data. The proposed approach combines the Reinforced…

Machine Learning · Computer Science 2025-10-28 Mohammad Hossein Jafari Naeimi , Ali Norouzi , Athena Abdi

Anomaly detection is critical in surveillance systems and patrol robots by identifying anomalous regions in images for early warning. Depending on whether reference data are utilized, anomaly detection can be categorized into anomaly…

Robotics · Computer Science 2024-08-23 Dong Li , Lineng Chen , Cheng-Zhong Xu , Hui Kong

Due to scarcity of anomaly situations in the early manufacturing stage, an unsupervised anomaly detection (UAD) approach is widely adopted which only uses normal samples for training. This approach is based on the assumption that the…

Computer Vision and Pattern Recognition · Computer Science 2023-11-13 YeongHyeon Park , Sungho Kang , Myung Jin Kim , Yeonho Lee , Hyeong Seok Kim , Juneho Yi

This paper considers few-shot anomaly detection (FSAD), a practical yet under-studied setting for anomaly detection (AD), where only a limited number of normal images are provided for each category at training. So far, existing FSAD studies…

Computer Vision and Pattern Recognition · Computer Science 2022-07-18 Chaoqin Huang , Haoyan Guan , Aofan Jiang , Ya Zhang , Michael Spratling , Yan-Feng Wang

While the mainstream research in anomaly detection has mainly followed the one-class classification, practical industrial environments often incur noisy training data due to annotation errors or lack of labels for new or refurbished…

Machine Learning · Computer Science 2024-11-26 Jiin Im , Yongho Son , Je Hyeong Hong

The rapid expansion of data from diverse sources has made anomaly detection (AD) increasingly essential for identifying unexpected observations that may signal system failures, security breaches, or fraud. As datasets become more complex…

Machine Learning · Computer Science 2025-03-18 Haoqi Huang , Ping Wang , Jianhua Pei , Jiacheng Wang , Shahen Alexanian , Dusit Niyato

Unsupervised anomaly detection (UAD) learns one-class classifiers exclusively with normal (i.e., healthy) images to detect any abnormal (i.e., unhealthy) samples that do not conform to the expected normal patterns. UAD has two main…

Computer Vision and Pattern Recognition · Computer Science 2021-07-01 Yu Tian , Guansong Pang , Fengbei Liu , Yuanhong chen , Seon Ho Shin , Johan W. Verjans , Rajvinder Singh , Gustavo Carneiro

Anomaly detection (AD) is often focused on detecting anomaly areas for industrial quality inspection and medical lesion examination. However, due to the specific scenario targets, the data scale for AD is relatively small, and evaluation…

Computer Vision and Pattern Recognition · Computer Science 2024-04-17 Jiangning Zhang , Chengjie Wang , Xiangtai Li , Guanzhong Tian , Zhucun Xue , Yong Liu , Guansong Pang , Dacheng Tao

Developing an accurate and fast anomaly detection model is an important task in real-time computer vision applications. There has been much research to develop a single model that detects either structural or logical anomalies, which are…

Computer Vision and Pattern Recognition · Computer Science 2024-12-10 Shota Sugawara , Ryuji Imamura