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Related papers: Regularized $M$-estimators of scatter matrix

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Estimating conditional dependence graphs and precision matrices are some of the most common problems in modern statistics and machine learning. When data are fully observed, penalized maximum likelihood-type estimators have become standard…

Machine Learning · Statistics 2019-04-09 Roger Fan , Byoungwook Jang , Yuekai Sun , Shuheng Zhou

We provide a unified approach to MM-estimation with auxiliary scale for balanced linear models with structured covariance matrices. This approach leads to estimators that are highly robust against outliers and highly efficient for normal…

Statistics Theory · Mathematics 2025-11-10 Hendrik Paul Lopuhaa

We consider the problem of estimating the scale matrix $\Sigma$ of the additif model $Y_{p\times n} = M + \mathcal{E}$, under a theoretical decision point of view. Here, $ p $ is the number of variables, $ n$ is the number of observations,…

Statistics Theory · Mathematics 2020-06-02 Mohamed Anis Haddouche , Dominique Fourdrinier , Fatiha Mezoued

In this paper we consider Tyler's robust covariance M-estimator under group symmetry constraints. We assume that the covariance matrix is invariant to the conjugation action of a unitary matrix group, referred to as group symmetry. Examples…

Applications · Statistics 2015-09-30 Ilya Soloveychik , Dmitry Trushin , Ami Wiesel

Location estimation is a central problem in functional data analysis. In this paper, we investigate penalized spline estimators of location for discretely sampled functional data under a broad class of convex loss functions. Our framework…

Methodology · Statistics 2025-08-19 Ioannis Kalogridis

We consider the matrix completion problem of recovering a structured matrix from noisy and partial measurements. Recent works have proposed tractable estimators with strong statistical guarantees for the case where the underlying matrix is…

Machine Learning · Statistics 2015-09-16 Suriya Gunasekar , Pradeep Ravikumar , Joydeep Ghosh

We consider the estimation of smoothing parameters and variance components in models with a regular log likelihood subject to quadratic penalization of the model coefficients, via a generalization of the method of Fellner (1986) and Schall…

Methodology · Statistics 2020-08-11 Simon N. Wood , Matteo Fasiolo

In this paper, we study the trace regression when a matrix of parameters B* is estimated via the convex relaxation of a rank-regularized regression or via regularized non-convex optimization. It is known that these estimators satisfy…

Machine Learning · Computer Science 2023-08-31 Nima Hamidi , Mohsen Bayati

The conditional gradient method (CGM) is widely used in large-scale sparse convex optimization, having a low per iteration computational cost for structured sparse regularizers and a greedy approach to collecting nonzeros. We explore the…

Optimization and Control · Mathematics 2021-07-05 Yifan Sun , Francis Bach

In this paper, we propose a regularized mixture probabilistic model to cluster matrix data and apply it to brain signals. The approach is able to capture the sparsity (low rank, small/zero values) of the original signals by introducing…

Methodology · Statistics 2018-08-07 Xu Gao , Weining Shen , Hernando Ombao

The truncated singular value decomposition may be used to find the solution of linear discrete ill-posed problems in conjunction with Tikhonov regularization and requires the estimation of a regularization parameter that balances between…

Numerical Analysis · Mathematics 2022-08-16 Rosemary A. Renaut , Anthony W. Helmstetter , Saeed Vatankhah

This paper analyzes the performance of Tyler's M-estimator of the scatter matrix in elliptical populations. We focus on the non-asymptotic setting and derive the estimation error bounds depending on the number of samples n and the dimension…

Statistics Theory · Mathematics 2015-06-18 Ilya Soloveychik , Ami Wiesel

Unbiased estimators are introduced for averaged Bregman divergences which generalize Stein's Unbiased (Predictive) Risk Estimator, and the minimization of these estimators is proposed as a regularization parameter selection method for…

Numerical Analysis · Mathematics 2021-11-22 Elias S. Helou , Sandra A. Santos , Lucas E. A. Simões

Low-rank matrix completion has achieved great success in many real-world data applications. A matrix factorization model that learns latent features is usually employed and, to improve prediction performance, the similarities between latent…

Machine Learning · Statistics 2020-01-28 Kaiyi Ji , Jian Tan , Jinfeng Xu , Yuejie Chi

This paper aims at presenting a simulative analysis of the main properties of a new $R$-estimator of shape matrices in Complex Elliptically Symmetric (CES) distributed observations. First proposed by Hallin, Oja and Paindaveine for the…

Signal Processing · Electrical Eng. & Systems 2020-06-23 Stefano Fortunati , Alexandre Renaux , Frédéric Pascal

Sparse approximate solutions to linear equations are classically obtained via L1 norm regularized least squares, but this method often underestimates the true solution. As an alternative to the L1 norm, this paper proposes a class of…

Optimization and Control · Mathematics 2018-03-20 Ivan Selesnick

In this paper, we investigate the matrix estimation problem in the multi-response regression model with measurement errors. A nonconvex error-corrected estimator based on a combination of the amended loss function and the nuclear norm…

Statistics Theory · Mathematics 2022-09-19 Xin Li , Dongya Wu

Inspired by ideas taken from the machine learning literature, new regularization techniques have been recently introduced in linear system identification. In particular, all the adopted estimators solve a regularized least squares problem,…

Systems and Control · Computer Science 2015-07-03 Gianluigi Pillonetto , Tianshi Chen , Alessandro Chiuso , Giuseppe De Nicolao , Lennart Ljung

The estimation of covariance matrices of multiple classes with limited training data is a difficult problem. The sample covariance matrix (SCM) is known to perform poorly when the number of variables is large compared to the available…

Methodology · Statistics 2021-11-10 Elias Raninen , Esa Ollila

This paper studies the limiting behavior of Tyler's M-estimator for the scatter matrix, in the regime that the number of samples $n$ and their dimension $p$ both go to infinity, and $p/n$ converges to a constant $y$ with $0<y<1$. We prove…

Statistics Theory · Mathematics 2016-04-04 Teng Zhang , Xiuyuan Cheng , Amit Singer
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