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Related papers: Outlier Detection with Cluster Catch Digraphs

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The random cluster model is used to define an upper bound on a distance measure as a function of the number of data points to be classified and the expected value of the number of classes to form in a hybrid K-means and regression…

Machine Learning · Computer Science 2016-02-12 Robert A. Murphy

Despite the rapid advance of unsupervised anomaly detection, existing methods require to train separate models for different objects. In this work, we present UniAD that accomplishes anomaly detection for multiple classes with a unified…

Computer Vision and Pattern Recognition · Computer Science 2022-10-26 Zhiyuan You , Lei Cui , Yujun Shen , Kai Yang , Xin Lu , Yu Zheng , Xinyi Le

Out-of-distribution (OOD) detection and segmentation are crucial for deploying machine learning models in safety-critical applications such as autonomous driving and robot-assisted surgery. While prior research has primarily focused on…

Computer Vision and Pattern Recognition · Computer Science 2026-03-05 Moru Liu , Hao Dong , Jessica Kelly , Olga Fink , Mario Trapp

Due to the intractability of characterizing everything that looks unlike the normal data, anomaly detection (AD) is traditionally treated as an unsupervised problem utilizing only normal samples. However, it has recently been found that…

Computer Vision and Pattern Recognition · Computer Science 2023-01-29 Philipp Liznerski , Lukas Ruff , Robert A. Vandermeulen , Billy Joe Franks , Klaus-Robert Müller , Marius Kloft

Modern graph or network datasets often contain rich structure that goes beyond simple pairwise connections between nodes. This calls for complex representations that can capture, for instance, edges of different types as well as so-called…

Social and Information Networks · Computer Science 2020-02-19 Ilya Amburg , Nate Veldt , Austin R. Benson

Vanilla CNNs, as uncalibrated classifiers, suffer from classifying out-of-distribution (OOD) samples nearly as confidently as in-distribution samples. To tackle this challenge, some recent works have demonstrated the gains of leveraging…

Machine Learning · Computer Science 2020-11-20 Mahdieh Abbasi , Changjian Shui , Arezoo Rajabi , Christian Gagne , Rakesh Bobba

To detect distribution shifts and improve model safety, many out-of-distribution (OOD) detection methods rely on the predictive uncertainty or features of supervised models trained on in-distribution data. In this paper, we critically…

Machine Learning · Computer Science 2025-07-03 Yucen Lily Li , Daohan Lu , Polina Kirichenko , Shikai Qiu , Tim G. J. Rudner , C. Bayan Bruss , Andrew Gordon Wilson

Many methods have been developed for data clustering, such as k-means, expectation maximization and algorithms based on graph theory. In this latter case, graphs are generally constructed by taking into account the Euclidian distance as a…

Data Analysis, Statistics and Probability · Physics 2011-01-27 Francisco A. Rodrigues , Guilherme Ferraz de Arruda , Luciano da Fontoura Costa

Outlier detection is a critical task in data mining, aimed at identifying objects that significantly deviate from the norm. Semi-supervised methods improve detection performance by leveraging partially labeled data but typically overlook…

Machine Learning · Computer Science 2025-12-23 Baiyang Chen , Zhong Yuan , Zheng Liu , Dezhong Peng , Yongxiang Li , Chang Liu , Guiduo Duan

In this paper we present methods for exemplar based clustering with outlier selection based on the facility location formulation. Given a distance function and the number of outliers to be found, the methods automatically determine the…

Machine Learning · Computer Science 2014-03-07 Lionel Ott , Linsey Pang , Fabio Ramos , David Howe , Sanjay Chawla

In a corpus of data, outliers are either errors: mistakes in the data that are counterproductive, or are unique: informative samples that improve model robustness. Identifying outliers can lead to better datasets by (1) removing noise in…

Outlier is the term that indicates in statistics an anomalous observation, aberrant, clearly distant from others collected observations. The outliers are the subject to animated discussions in various contexts with regard to be or not to be…

Applications · Statistics 2014-03-24 Gianluca Rosso

Detecting a small number of outliers from a set of data observations is always challenging. This problem is more difficult in the setting of multiple network samples, where computing the anomalous degree of a network sample is generally not…

Artificial Intelligence · Computer Science 2016-10-04 Xuan-Hong Dang , Arlei Silva , Ambuj Singh , Ananthram Swami , Prithwish Basu

Selecting and combining the outlier scores of different base detectors used within outlier ensembles can be quite challenging in the absence of ground truth. In this paper, an unsupervised outlier detector combination framework called DCSO…

Machine Learning · Computer Science 2019-11-26 Yue Zhao , Maciej K. Hryniewicki

It has become routine in neuroscience studies to measure brain networks for different individuals using neuroimaging. These networks are typically expressed as adjacency matrices, with each cell containing a summary of connectivity between…

Methodology · Statistics 2022-06-30 Pritam Dey , Zhengwu Zhang , David B. Dunson

Outlier detection (OD) is a key machine learning (ML) task for identifying abnormal objects from general samples with numerous high-stake applications including fraud detection and intrusion detection. Due to the lack of ground truth…

In this paper, we consider clustering data that is assumed to come from one of finitely many pointed convex polyhedral cones. This model is referred to as the Union of Polyhedral Cones (UOPC) model. Similar to the Union of Subspaces (UOS)…

Machine Learning · Statistics 2017-11-03 Wenqi Wang , Vaneet Aggarwal , Shuchin Aeron

There have been significant advancements in anomaly detection in an unsupervised manner, where only normal images are available for training. Several recent methods aim to detect anomalies based on a memory, comparing or reconstructing the…

Computer Vision and Pattern Recognition · Computer Science 2024-07-25 Joo Chan Lee , Taejune Kim , Eunbyung Park , Simon S. Woo , Jong Hwan Ko

Current modularity-based community detection algorithms attempt to find cluster memberships that maximize modularity within a fixed graph topology. Diverging from this conventional approach, our work introduces a novel strategy that employs…

Data Analysis, Statistics and Probability · Physics 2024-02-27 Yongyu Wang , Shiqi Hao , Xiaoyang Wang , Xiaotian Zhuang

The unsupervised outlier detection (UOD) problem refers to a task to identify inliers given training data which contain outliers as well as inliers, without any labeled information about inliers and outliers. It has been widely recognized…

Machine Learning · Statistics 2024-07-17 Dongha Kim , Jaesung Hwang , Jongjin Lee , Kunwoong Kim , Yongdai Kim