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Related papers: A robust method for cluster analysis

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We consider the problem of clustering data points coming from sub-Gaussian mixtures. Existing methods that provably achieve the optimal mislabeling error, such as the Lloyd algorithm, are usually vulnerable to outliers. In contrast,…

Statistics Theory · Mathematics 2025-11-03 Soham Jana , Kun Yang , Sanjeev Kulkarni

Good robust estimators can be tuned to combine a high breakdown point and a specified asymptotic efficiency at a central model. This happens in regression with MM- and tau-estimators among others. However, the finite-sample efficiency of…

Statistics Theory · Mathematics 2013-11-21 Ricardo Maronna , Víctor Yohai

The generalized log-gamma (GLG) model is a very flexible family of distributions to analyze datasets in many different areas of science and technology. In this paper, we propose estimators which are simultaneously highly robust and highly…

Methodology · Statistics 2015-12-07 Claudio Agostinelli , Isabella Locatelli , Alfio Marazzi , Victor J. Yohai

A weighted likelihood approach for robust fitting of a mixture of multivariate Gaussian components is developed in this work. Two approaches have been proposed that are driven by a suitable modification of the standard EM and CEM…

Methodology · Statistics 2018-11-19 Luca Greco , Claudio Agostinelli

Determining the number of clusters is a fundamental issue in data clustering. Several algorithms have been proposed, including centroid-based algorithms using the Euclidean distance and model-based algorithms using a mixture of probability…

Machine Learning · Computer Science 2024-07-30 Ryosuke Motegi , Yoichi Seki

The two main topics of this paper are the introduction of the "optimally tuned improper maximum likelihood estimator" (OTRIMLE) for robust clustering based on the multivariate Gaussian model for clusters, and a comprehensive simulation…

Methodology · Statistics 2017-01-31 Pietro Coretto , Christian Hennig

We consider the problem of multivariate location and scatter matrix estimation when the data contain cellwise and casewise outliers. Agostinelli et al. (2015) propose a two-step approach to deal with this problem: first, apply a univariate…

Statistics Theory · Mathematics 2016-12-28 Andy Leung , Victor J. Yohai , Ruben H. Zamar

Clustering, or unsupervised classification, is a task often plagued by outliers. Yet there is a paucity of work on handling outliers in clustering. Outlier identification algorithms tend to fall into three broad categories: outlier…

Methodology · Statistics 2024-05-31 Katharine M. Clark , Paul D. McNicholas

We introduce a new approach to deciding the number of clusters. The approach is applied to Optimally Tuned Robust Improper Maximum Likelihood Estimation (OTRIMLE; Coretto and Hennig 2016) of a Gaussian mixture model allowing for…

Methodology · Statistics 2020-12-29 Christian Hennig , Pietro Coretto

In this paper we introduce two procedures for variable selection in cluster analysis and classification rules. One is mainly oriented to detect the noisy non-informative variables, while the other deals also with multicolinearity. A…

Statistics Theory · Mathematics 2023-12-29 Ricardo Fraiman , Ana Justel , Marcela Svarc

One basic requirement of many studies is the necessity of classifying data. Clustering is a proposed method for summarizing networks. Clustering methods can be divided into two categories named model-based approaches and algorithmic…

Machine Learning · Computer Science 2013-02-19 Raheleh Namayandeh , Farzad Didehvar , Zahra Shojaei

In cluster analysis interest lies in probabilistically capturing partitions of individuals, items or observations into groups, such that those belonging to the same group share similar attributes or relational profiles. Bayesian posterior…

Methodology · Statistics 2017-03-23 Riccardo Rastelli , Nial Friel

Gaussian mixture models are widely used to study clustering problems. These model-based clustering methods require an accurate estimation of the unknown data density by Gaussian mixtures. In Maugis and Michel (2009), a penalized maximum…

Statistics Theory · Mathematics 2015-03-19 Maugis Cathy , Michel Bertrand

This paper considers the problem of estimating the population spectral distribution from a sample covariance matrix in large dimensional situations. We generalize the contour-integral based method in Mestre (2008) and present a local moment…

Methodology · Statistics 2013-02-05 Weiming Li , Jianfeng Yao

We propose a simple and efficient clustering method for high-dimensional data with a large number of clusters. Our algorithm achieves high-performance by evaluating distances of datapoints with a subset of the cluster centres. Our…

Machine Learning · Computer Science 2022-03-30 Georgios Exarchakis , Omar Oubari , Gregor Lenz

In the context of clustering, we assume a generative model where each cluster is the result of sampling points in the neighborhood of an embedded smooth surface; the sample may be contaminated with outliers, which are modeled as points…

Machine Learning · Statistics 2011-11-30 Ery Arias-Castro , Guangliang Chen , Gilad Lerman

Variable selection in cluster analysis is important yet challenging. It can be achieved by regularization methods, which realize a trade-off between the clustering accuracy and the number of selected variables by using a lasso-type penalty.…

Methodology · Statistics 2016-12-23 Marbac Matthieu , Sedki Mohammed

We consider the problem of estimating the common mean of independently sampled data, where samples are drawn in a possibly non-identical manner from symmetric, unimodal distributions with a common mean. This generalizes the setting of…

Statistics Theory · Mathematics 2019-07-09 Ankit Pensia , Varun Jog , Po-Ling Loh

We introduce a new family of estimators for unnormalized statistical models. Our family of estimators is parameterized by two nonlinear functions and uses a single sample from an auxiliary distribution, generalizing Maximum Likelihood Monte…

Machine Learning · Computer Science 2012-03-19 Miika Pihlaja , Michael Gutmann , Aapo Hyvarinen

This work introduces the Matrix Minimum Covariance Determinant (MMCD) method, a novel robust location and covariance estimation procedure designed for data that are naturally represented in the form of a matrix. Unlike standard robust…

Methodology · Statistics 2025-03-17 Marcus Mayrhofer , Una Radojičić , Peter Filzmoser