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Related papers: On computing sparse generalized inverses

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We consider linear inverse problems where the solution is assumed to have a sparse expansion on an arbitrary pre-assigned orthonormal basis. We prove that replacing the usual quadratic regularizing penalties by weighted l^p-penalties on the…

Functional Analysis · Mathematics 2025-10-20 Ingrid Daubechies , Michel Defrise , Christine De Mol

Gr{\"o}bner bases is one the most powerful tools in algorithmic non-linear algebra. Their computation is an intrinsically hard problem with a complexity at least single exponential in the number of variables. However, in most of the cases,…

Symbolic Computation · Computer Science 2019-02-04 Matías Bender , Jean-Charles Faugère , Elias Tsigaridas

We consider a class of optimization problems for sparse signal reconstruction which arise in the field of Compressed Sensing (CS). A plethora of approaches and solvers exist for such problems, for example GPSR, FPC AS, SPGL1, NestA,…

Optimization and Control · Mathematics 2013-11-19 Kimon Fountoulakis , Jacek Gondzio , Pavel Zhlobich

Sparse recovery is one of the most fundamental and well-studied inverse problems. Standard statistical formulations of the problem are provably solved by general convex programming techniques and more practical, fast (nearly-linear time)…

Data Structures and Algorithms · Computer Science 2022-03-09 Jonathan A. Kelner , Jerry Li , Allen Liu , Aaron Sidford , Kevin Tian

We propose new methods for multivariate linear regression when the regression coefficient matrix is sparse and the error covariance matrix is dense. We assume that the error covariance matrix has equicorrelation across the response…

Methodology · Statistics 2025-08-13 Daeyoung Ham , Bradley S. Price , Adam J. Rothman

The Restricted Isometry Property (RIP) is a fundamental property of a matrix which enables sparse recovery. Informally, an $m \times n$ matrix satisfies RIP of order $k$ for the $\ell_p$ norm, if $\|Ax\|_p \approx \|x\|_p$ for every vector…

Data Structures and Algorithms · Computer Science 2015-02-24 Zeyuan Allen-Zhu , Rati Gelashvili , Ilya Razenshteyn

The Sparse Approximation problem asks to find a solution $x$ such that $||y - Hx|| < \alpha$, for a given norm $||\cdot||$, minimizing the size of the support $||x||_0 := \#\{j \ |\ x_j \neq 0 \}$. We present valid inequalities for Mixed…

Discrete Mathematics · Computer Science 2020-09-15 Diego Delle Donne , Matthieu Kowalski , Leo Liberti

Pan-sharpening algorithms utilize a panchromatic image and a multispectral image to generate a high spatial and high spectral image. However, the optimizations of the algorithms are designed with different standards. We employ a simple…

Machine Learning · Computer Science 2025-07-17 Shiqi Liu , Yihua Tan , Yutong Bai , Alan Yuille

Inverse problems arise in a wide spectrum of applications in fields ranging from engineering to scientific computation. Connected with the rise of interest in inverse problems is the development and analysis of regularization methods, such…

Numerical Analysis · Mathematics 2025-05-12 Abinash Nayak

Many practical applications such as gene expression analysis, multi-task learning, image recognition, signal processing, and medical data analysis pursue a sparse solution for the feature selection purpose and particularly favor the…

Machine Learning · Statistics 2015-10-28 Yijun Huang , Ji Liu

Recently, the worse-case analysis, probabilistic analysis and empirical justification have been employed to address the fundamental question: When does $\ell_1$-minimization find the sparsest solution to an underdetermined linear system? In…

Information Theory · Computer Science 2015-06-16 Yunbin Zhao

Several methods have been recently proposed for estimating sparse Gaussian graphical models using $\ell_{1}$ regularization on the inverse covariance matrix. Despite recent advances, contemporary applications require methods that are even…

Computation · Statistics 2014-05-15 Onkar Dalal , Bala Rajaratnam

Approximate inference via information projection has been recently introduced as a general-purpose approach for efficient probabilistic inference given sparse variables. This manuscript goes beyond classical sparsity by proposing efficient…

Machine Learning · Statistics 2016-07-13 Rajiv Khanna , Joydeep Ghosh , Russell Poldrack , Oluwasanmi Koyejo

Sparse channel estimation for massive multiple-input multiple-output systems has drawn much attention in recent years. The required pilots are substantially reduced when the sparse channel state vectors can be reconstructed from a few…

Information Theory · Computer Science 2021-02-17 Pengxia Wu , Hui Ma , Julian Cheng

We explore a new type of sparsity for the generalized moment problem (GMP) that we call ideal-sparsity. This sparsity exploits the presence of equality constraints requiring the measure to be supported on the variety of an ideal generated…

Optimization and Control · Mathematics 2023-07-11 Milan Korda , Monique Laurent , Victor Magron , Andries Steenkamp

This paper addresses the problem of sparsity penalized least squares for applications in sparse signal processing, e.g. sparse deconvolution. This paper aims to induce sparsity more strongly than L1 norm regularization, while avoiding…

Machine Learning · Computer Science 2015-06-15 Ivan W. Selesnick , Ilker Bayram

In compressed sensing, the l0-norm minimization of sparse signal reconstruction is NP-hard. Recent work shows that compared with the best convex relaxation (l1-norm), nonconvex penalties can better approximate the l0-norm and can…

Signal Processing · Electrical Eng. & Systems 2018-05-03 Hao Wang , Zhanglei Shi , Chi-Sing Leung , Hing Cheung So

The computation of the sparse principal component of a matrix is equivalent to the identification of its principal submatrix with the largest maximum eigenvalue. Finding this optimal submatrix is what renders the problem…

Information Theory · Computer Science 2013-12-23 Megasthenis Asteris , Dimitris S. Papailiopoulos , George N. Karystinos

Matrix completion constantly receives tremendous attention from many research fields. It is commonly applied for recommender systems such as movie ratings, computer vision such as image reconstruction or completion, multi-task learning such…

Machine Learning · Computer Science 2019-10-08 Abdallah Chehade , Zunya Shi

We generalize the Wedderburn rank reduction formula by replacing the inverse with the Moore--Penrose pseudoinverse. In particular, this allows one to remove the non--singularity of a certain matrix from assumptions. The results implies in a…

Numerical Analysis · Mathematics 2024-06-07 Oskar Kędzierski