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Related papers: Iteratively Reweighted $\ell_1$ Approaches to Spar…

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$L_1$ regularization is used for finding sparse solutions to an underdetermined linear system. As sparse signals are widely expected in remote sensing, this type of regularization scheme and its extensions have been widely employed in many…

Image and Video Processing · Electrical Eng. & Systems 2018-05-07 Yilei Shi , Xiao Xiang Zhu , Wotao Yin , Richard Bamler

The $\ell_1$ norm is the tight convex relaxation for the $\ell_0$ "norm" and has been successfully applied for recovering sparse signals. For problems with fewer samplings, one needs to enhance the sparsity by nonconvex penalties such as…

Optimization and Control · Mathematics 2016-01-05 Xiaolin Huang , Lei Shi , Ming Yan

This paper presents a novel L1-norm semi-supervised learning algorithm for robust image analysis by giving new L1-norm formulation of Laplacian regularization which is the key step of graph-based semi-supervised learning. Since our L1-norm…

Computer Vision and Pattern Recognition · Computer Science 2017-07-04 Zhiwu Lu , Yuxin Peng

In this paper, we focus on the local convergence rate analysis of the proximal iteratively reweighted $\ell_1$ algorithms for solving $\ell_p$ regularization problems, which are widely applied for inducing sparse solutions. We show that if…

Optimization and Control · Mathematics 2021-01-12 Hao Wang , Hao Zeng , Jiashan Wang

We know that compressive sensing can establish stable sparse recovery results from highly undersampled data under a restricted isometry property condition. In reality, however, numerous problems are coherent, and vast majority conventional…

Optimization and Control · Mathematics 2021-11-25 Yanyun Ding , Haibin Zhang , Peili Li , Yunhai Xiao

In high dimension, it is customary to consider Lasso-type estimators to enforce sparsity. For standard Lasso theory to hold, the regularization parameter should be proportional to the noise level, yet the latter is generally unknown in…

Machine Learning · Statistics 2017-10-19 Mathurin Massias , Olivier Fercoq , Alexandre Gramfort , Joseph Salmon

We study the problem of recovering the underlining sparse signals from clean or noisy phaseless measurements. Due to the sparse prior of signals, we adopt an L0regularized variational model to ensure only a small number of nonzero elements…

Optimization and Control · Mathematics 2016-12-09 Yuping Duan , Chunlin Wu , Zhi-Feng Pang , Huibin Chang

Noiseless compressive sensing is a protocol that enables undersampling and later recovery of a signal without loss of information. This compression is possible because the signal is usually sufficiently sparse in a given basis. Currently,…

Information Theory · Computer Science 2024-07-22 D. Barbier , C Lucibello , L. Saglietti , F. Krzakala , L. Zdeborova

Regularization plays an important role in solving ill-posed problems by adding extra information about the desired solution, such as sparsity. Many regularization terms usually involve some vector norm, e.g., $L_1$ and $L_2$ norms. In this…

Numerical Analysis · Mathematics 2021-03-10 Weihong Guo , Yifei Lou , Jing Qin , Ming Yan

l1 reweighting algorithms are very popular in sparse signal recovery and compressed sensing, since in the practice they have been observed to outperform classical l1 methods. Nevertheless, the theoretical analysis of their convergence is a…

Machine Learning · Computer Science 2018-12-10 Sophie M. Fosson

We develop a Recursive $\mathcal{L}_1$-Regularized Least Squares (SPARLS) algorithm for the estimation of a sparse tap-weight vector in the adaptive filtering setting. The SPARLS algorithm exploits noisy observations of the tap-weight…

Information Theory · Computer Science 2009-01-08 Behtash Babadi , Nicholas Kalouptsidis , Vahid Tarokh

The iteratively reweighted l1 algorithm is a widely used method for solving various regularization problems, which generally minimize a differentiable loss function combined with a nonconvex regularizer to induce sparsity in the solution.…

Optimization and Control · Mathematics 2021-01-12 Hao Wang , Hao Zeng , Jiashan Wang

In this paper we introduce a nonuniform sparsity model and analyze the performance of an optimized weighted $\ell_1$ minimization over that sparsity model. In particular, we focus on a model where the entries of the unknown vector fall into…

Information Theory · Computer Science 2010-09-21 M. Amin Khajehnejad , Weiyu Xu , A. Salman Avestimehr , Babak Hassibi

When we are interested in high-dimensional system and focus on classification performance, the $\ell_{1}$-penalized logistic regression is becoming important and popular. However, the Lasso estimates could be problematic when penalties of…

Machine Learning · Statistics 2020-06-12 Huamei Huang , Yujing Gao , Huiming Zhang , Bo Li

In this paper we study the compressed sensing problem of recovering a sparse signal from a system of underdetermined linear equations when we have prior information about the probability of each entry of the unknown signal being nonzero. In…

Information Theory · Computer Science 2009-01-20 M. Amin Khajehnejad , Weiyu Xu , Salman Avestimehr , Babak Hassibi

Noiseless compressive sensing is a two-steps setting that allows for undersampling a sparse signal and then reconstructing it without loss of information. The LASSO algorithm, based on $\lone$ regularization, provides an efficient and…

Information Theory · Computer Science 2025-11-13 Damien Barbier , Carlo Lucibello , Luca Saglietti , Florent Krzakala , Lenka Zdeborová

In this paper, we carry out a unified study for $L_1$ over $L_2$ sparsity promoting models, which are widely used in the regime of coherent dictionaries for recovering sparse nonnegative/arbitrary signals. First, we provide a unified…

Optimization and Control · Mathematics 2023-01-24 Min Tao , Xiao-Ping Zhang

Inspired by several recent developments in regularization theory, optimization, and signal processing, we present and analyze a numerical approach to multi-penalty regularization in spaces of sparsely represented functions. The sparsity…

Numerical Analysis · Mathematics 2014-11-25 Valeriya Naumova , Steffen Peter

In this work we present a novel optimization strategy for image reconstruction tasks under analysis-based image regularization, which promotes sparse and/or low-rank solutions in some learned transform domain. We parameterize such…

Computer Vision and Pattern Recognition · Computer Science 2023-08-11 Iaroslav Koshelev , Stamatios Lefkimmiatis

Iterative regularization exploits the implicit bias of an optimization algorithm to regularize ill-posed problems. Constructing algorithms with such built-in regularization mechanisms is a classic challenge in inverse problems but also in…

Optimization and Control · Mathematics 2022-02-02 Cesare Molinari , Mathurin Massias , Lorenzo Rosasco , Silvia Villa