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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

In this study, we propose a robust mixture regression procedure based on the skew t distribution to model heavy-tailed and/or skewed errors in a mixture regression setting. Using the scale mixture representation of the skew t distribution,…

Statistics Theory · Mathematics 2017-06-12 Fatma Zehra Doğru , Olcay Arslan

Let there be given a contaminated list of n R^d-valued observations coming from g different, normally distributed populations with a common covariance matrix. We compute the ML-estimator with respect to a certain statistical model with n-r…

Statistics Theory · Mathematics 2007-06-13 Maria Teresa Gallegos , Gunter Ritter

We propose a class of robust estimates for multivariate linear models. Based on the approach of MM estimation (Yohai 1987), we estimate the regression coefficients and the covariance matrix of the errors simultaneously. These estimates have…

Statistics Theory · Mathematics 2025-12-03 Nadia L. Kudraszow , Ricardo A. Maronna

We propose a versatile and computationally efficient estimating equation method for a class of hierarchical multiplicative generalized linear mixed models with additive dispersion components, based on explicit modelling of the covariance…

Methodology · Statistics 2010-08-18 René Holst , Bent Jørgensen

We study the fundamental task of outlier-robust mean estimation for heavy-tailed distributions in the presence of sparsity. Specifically, given a small number of corrupted samples from a high-dimensional heavy-tailed distribution whose mean…

Data Structures and Algorithms · Computer Science 2022-11-30 Ilias Diakonikolas , Daniel M. Kane , Jasper C. H. Lee , Ankit Pensia

A highly popular regularized (shrinkage) covariance matrix estimator is the shrinkage sample covariance matrix (SCM) which shares the same set of eigenvectors as the SCM but shrinks its eigenvalues toward the grand mean of the eigenvalues…

Methodology · Statistics 2020-10-29 Esa Ollila , Daniel P. Palomar , Frédéric Pascal

We address the problem of robust estimation of sparse high dimensional tensor elliptical graphical model. Most of the research focus on tensor graphical model under normality. To extend the tensor graphical model to more heavy-tailed…

Methodology · Statistics 2025-08-04 Jixuan Liu , Zhengke Lu , Le Zhou , Long Feng , Zhaojun Wang

For nonlinear dispersive systems, the nonlinear Schr\"odinger (NLS) equation can usually be derived as a formal approximation equation describing slow spatial and temporal modulations of the envelope of a spatially and temporally…

Analysis of PDEs · Mathematics 2021-01-18 Max Heß

We propose elliptical graphical models based on conditional uncorrelatedness as a general- ization of Gaussian graphical models by letting the population distribution be elliptical instead of normal, allowing the fitting of data with…

Methodology · Statistics 2015-06-16 Daniel Vogel , Roland Fried

The likelihood functions for discretely observed nonlinear continuous-time models based on stochastic differential equations are not available except for a few cases. Various parameter estimation techniques have been proposed, each with…

Methodology · Statistics 2025-04-17 Predrag Pilipovic , Adeline Samson , Susanne Ditlevsen

In this paper we describe a probabilistic method for estimating the position of an object along with its covariance matrix using neural networks. Our method is designed to be robust to outliers, have bounded gradients with respect to the…

Computer Vision and Pattern Recognition · Computer Science 2021-11-22 David Mohlin , Gerald Bianchi , Josephine Sullivan

Shrinkage estimators of covariance are an important tool in modern applied and theoretical statistics. They play a key role in regularized estimation problems, such as ridge regression (aka Tykhonov regularization), regularized discriminant…

Statistics Theory · Mathematics 2011-05-10 Noureddine El Karoui , Holger Koesters

Estimating a covariance matrix is an important task in applications where the number of variables is larger than the number of observations. Shrinkage approaches for estimating a high-dimensional covariance matrix are often employed to…

Methodology · Statistics 2015-06-18 Anestis Touloumis

This work concerns estimation of multidimensional nonlinear regression models using multilayer perceptron (MLP). The main problem with such model is that we have to know the covariance matrix of the noise to get optimal estimator. however…

Statistics Theory · Mathematics 2008-02-22 Joseph Rynkiewicz

We observe a $n$-sample, the distribution of which is assumed to belong, or at least to be close enough, to a given mixture model. We propose an estimator of this distribution that belongs to our model and possesses some robustness…

Statistics Theory · Mathematics 2025-02-06 Alexandre Lecestre

A popular regularized (shrinkage) covariance estimator is the shrinkage sample covariance matrix (SCM) which shares the same set of eigenvectors as the SCM but shrinks its eigenvalues toward its grand mean. In this paper, a more general…

Methodology · Statistics 2020-02-13 Esa Ollila , Daniel P. Palomar , Frederic Pascal

In many learning problems, the training and testing data follow different distributions and a particularly common situation is the \textit{covariate shift}. To correct for sampling biases, most approaches, including the popular kernel mean…

Machine Learning · Computer Science 2020-03-13 Henry Lam , Fengpei Li , Siddharth Prusty

Although linear regression models are fundamental tools in statistical science, the estimation results can be sensitive to outliers. While several robust methods have been proposed in frequentist frameworks, statistical inference is not…

Methodology · Statistics 2020-07-15 Shintaro Hashimoto , Shonosuke Sugasawa

Consider estimating the n by p matrix of means of an n by p matrix of independent normally distributed observations with constant variance, where the performance of an estimator is judged using a p by p matrix quadratic error loss function.…

Statistics Theory · Mathematics 2011-01-19 Reman Abu-Shanab , John T. Kent , William E. Strawderman