English
Related papers

Related papers: Outlier detection in non-elliptical data by kernel…

200 papers

The task of outlier detection is to find small groups of data objects that are exceptional when compared with rest large amount of data. Detection of such outliers is important for many applications such as fraud detection and customer…

Databases · Computer Science 2007-05-23 Zengyou He , Xiaofei Xu , Shengchun Deng

This paper studies the outlier detection problem from the point of view of penalized regressions. Our regression model adds one mean shift parameter for each of the $n$ data points. We then apply a regularization favoring a sparse vector of…

Methodology · Statistics 2011-10-18 Yiyuan She , Art B. Owen

Kernel segmentation aims at partitioning a data sequence into several non-overlapping segments that may have nonlinear and complex structures. In general, it is formulated as a discrete optimization problem with combinatorial constraints. A…

Machine Learning · Computer Science 2022-06-23 Tung Doan , Atsuhiro Takasu

Outlier detection is an important task in data mining and many technologies have been explored in various applications. However, due to the default assumption that outliers are non-concentrated, unsupervised outlier detection may not…

Machine Learning · Computer Science 2020-03-10 Zhe Li , Chunhua Sun , Chunli Liu , Xiayu Chen , Meng Wang , Yezheng Liu

Deep sparse auto-encoders with mixed structure regularization (MSR) in addition to explicit sparsity regularization term and stochastic corruption of the input data with Gaussian noise have the potential to improve unsupervised abnormality…

Computer Vision and Pattern Recognition · Computer Science 2019-03-05 Moti Freiman , Ravindra Manjeshwar , Liran Goshen

Distributionally robust optimization (DRO) has attracted attention in machine learning due to its connections to regularization, generalization, and robustness. Existing work has considered uncertainty sets based on phi-divergences and…

Machine Learning · Computer Science 2019-05-28 Matthew Staib , Stefanie Jegelka

We introduce a data-based approach to estimating key quantities which arise in the study of nonlinear control systems and random nonlinear dynamical systems. Our approach hinges on the observation that much of the existing linear theory may…

Optimization and Control · Mathematics 2016-04-04 Jake Bouvrie , Boumediene Hamzi

Outlier detection is an integral part of robust evaluation for crowdsourceable Quality of Experience (QoE) and has attracted much attention in recent years. In QoE for multimedia, outliers happen because of different test conditions, human…

Multimedia · Computer Science 2014-10-23 Qianqian Xu , Ming Yan , Yuan Yao

We study modeling and inference with the Elliptical Gamma Distribution (EGD). We consider maximum likelihood (ML) estimation for EGD scatter matrices, a task for which we develop new fixed-point algorithms. Our algorithms are efficient and…

Computation · Statistics 2018-06-04 Reshad Hosseini , Suvrit Sra , Lucas Theis , Matthias Bethge

Detecting abrupt changes in data distribution is one of the most significant tasks in streaming data analysis. Although many unsupervised Change-Point Detection (CPD) methods have been proposed recently to identify those changes, they still…

Machine Learning · Computer Science 2024-04-26 Yang Cao , Ye Zhu , Kai Ming Ting , Flora D. Salim , Hong Xian Li , Luxing Yang , Gang Li

We propose an inlier-based outlier detection method capable of both identifying the outliers and explaining why they are outliers, by identifying the outlier-specific features. Specifically, we employ an inlier-based outlier detection…

Machine Learning · Statistics 2017-02-22 Makoto Yamada , Song Liu , Samuel Kaski

Various approaches have been proposed for out-of-distribution (OOD) detection by augmenting models, input examples, training sets, and optimization objectives. Deviating from existing work, we have a simple hypothesis that standard…

Machine Learning · Computer Science 2022-03-29 Xin Dong , Junfeng Guo , Ang Li , Wei-Te Ting , Cong Liu , H. T. Kung

In statistics and machine learning, the traditional meaning of the terms `outlier' and `anomaly' is a case in the dataset that behaves differently from the bulk of the data. This raises suspicion that it may belong to a different…

Methodology · Statistics 2026-04-17 Mia Hubert , Jakob Raymaekers , Peter J. Rousseeuw

A large dimensional characterization of robust M-estimators of covariance (or scatter) is provided under the assumption that the dataset comprises independent (essentially Gaussian) legitimate samples as well as arbitrary deterministic…

Statistics Theory · Mathematics 2015-10-28 David Morales-Jimenez , Romain Couillet , Matthew R. McKay

Several emerging post-Bayesian methods target a probability distribution for which an entropy-regularised variational objective is minimised. This increased flexibility introduces a computational challenge, as one loses access to an…

Computation · Statistics 2025-12-17 Clémentine Chazal , Heishiro Kanagawa , Zheyang Shen , Anna Korba , Chris. J. Oates

Many scientific problems involve data exhibiting both temporal and cross-sectional dependencies. While linear dependencies have been extensively studied, the theoretical analysis of regression estimators under nonlinear dependencies remains…

Statistics Theory · Mathematics 2025-02-27 Marie-Christine Düker , Adam Waterbury

Recently, the robustification of principal component analysis has attracted lots of attention from statisticians, engineers and computer scientists. In this work we study the type of outliers that are not necessarily apparent in the…

Methodology · Statistics 2016-01-29 Yiyuan She , Shijie Li , Dapeng Wu

Out-of-Distribution (OoD) detection is vital for the reliability of deep neural networks, the key of which lies in effectively characterizing the disparities between OoD and In-Distribution (InD) data. In this work, such disparities are…

Machine Learning · Computer Science 2025-05-22 Kun Fang , Qinghua Tao , Mingzhen He , Kexin Lv , Runze Yang , Haibo Hu , Xiaolin Huang , Jie Yang , Longbin Cao

We developed a novel direct algorithm to derive the mass-ratio distribution (MRD) of short-period binaries from an observed sample of single-lined spectroscopic binaries (SB1). The algorithm considers a class of parameterized MRDs and finds…

Instrumentation and Methods for Astrophysics · Physics 2017-10-18 Sahar Shahaf , Tsevi Mazeh , Simchon Faigler

Learning from data in the presence of outliers is a fundamental problem in statistics. Until recently, no computationally efficient algorithms were known to compute the mean of a high dimensional distribution under natural assumptions in…

Data Structures and Algorithms · Computer Science 2021-01-22 Yeshwanth Cherapanamjeri , Sidhanth Mohanty , Morris Yau