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This paper tackles the challenging problem of finding global optimal solutions for two-stage stochastic programs with continuous decision variables and nonconvex recourse functions. We introduce a two-phase approach. The first phase…

Optimization and Control · Mathematics 2024-05-29 Suhan Zhong , Ying Cui , Jiawang Nie

LSMR is a widely recognized method for solving least squares problems via the double QR decomposition. Various preconditioning techniques have been explored to improve its efficiency. One issue that arises when implementing these…

Numerical Analysis · Mathematics 2024-08-30 Mei Yang , Gul Karaduman , Ren-Cang Li

In Part I of this paper, we proposed and analyzed a novel algorithmic framework for the minimization of a nonconvex (smooth) objective function, subject to nonconvex constraints, based on inner convex approximations. This Part II is devoted…

Information Theory · Computer Science 2017-04-05 Gesualdo Scutari , Francisco Facchinei , Lorenzo Lampariello , Peiran Song , Stefania Sardellitti

There are a large number of methods for solving under-determined linear inverse problem. Many of them have very high time complexity for large datasets. We propose a new method called Two-Stage Sparse Representation (TSSR) to tackle this…

Computer Vision and Pattern Recognition · Computer Science 2015-12-09 Chengyu Peng , Hong Cheng , Manchor Ko

We study the problem of exact support recovery: given an (unknown) vector $\theta \in \left\{-1,0,1\right\}^D$, we are given access to the noisy measurement $$ y = X\theta + \omega,$$ where $X \in \mathbb{R}^{N \times D}$ is a (known)…

Statistics Theory · Mathematics 2020-11-10 Ofir Lindenbaum , Stefan Steinerberger

It is well known that for singular inconsistent range-symmetric linear systems, the generalized minimal residual (GMRES) method determines a least squares solution without breakdown. The reached least squares solution may be or not be the…

Numerical Analysis · Mathematics 2024-01-24 Kui Du , Jia-Jun Fan , Fang Wang

This paper deals with finding an $n$-dimensional solution $x$ to a system of quadratic equations of the form $y_i=|\langle{a}_i,x\rangle|^2$ for $1\le i \le m$, which is also known as phase retrieval and is NP-hard in general. We put forth…

Optimization and Control · Mathematics 2017-05-31 Gang Wang , Georgios B. Giannakis , Yousef Saad , Jie Chen

Channel estimation poses significant challenges in millimeter-wave massive multiple-input multiple-output systems, especially when the base station has fewer radio-frequency chains than antennas. To address this challenge, one promising…

Information Theory · Computer Science 2024-08-07 Pengxia Wu , Julian Cheng , Yonina C. Eldar , John M. Cioffi

The development of efficient and accurate image reconstruction algorithms is one of the cornerstones of computed tomography. Existing algorithms for quantitative photoacoustic tomography currently operate in a two-stage procedure: First an…

Analysis of PDEs · Mathematics 2015-05-20 Markus Haltmeier , Lukas Neumann , Simon Rabanser

The a posteriori error estimator using the least-squares functional can be used for adaptive mesh refinement and error control even if the numerical approximations are not obtained from the corresponding least-squares method. This suggests…

Numerical Analysis · Mathematics 2024-07-19 Ziyan Li , Shun Zhang

In this paper, we propose deep partial least squares for the estimation of high-dimensional nonlinear instrumental variable regression. As a precursor to a flexible deep neural network architecture, our methodology uses partial least…

Methodology · Statistics 2023-06-06 Maria Nareklishvili , Nicholas Polson , Vadim Sokolov

In this paper, we study a fast approximation method for {\it large-scale high-dimensional} sparse least-squares regression problem by exploiting the Johnson-Lindenstrauss (JL) transforms, which embed a set of high-dimensional vectors into a…

Statistics Theory · Mathematics 2015-07-21 Tianbao Yang , Lijun Zhang , Qihang Lin , Rong Jin

This paper considers robust solutions to a class of nonlinear least squares problems using min-max optimization approach. We give an explicit formula for the value function of the inner maximization problem and show the existence of global…

Optimization and Control · Mathematics 2025-02-03 Xiaojun Chen , Carl Kelley

It has previously been shown that ordinary least squares can be used to estimate the coefficients of the single-index model under only mild conditions. However, the estimator is non-robust leading to poor estimates for some models. In this…

Methodology · Statistics 2022-09-13 Marina Masioti , Joshua Davies , Amanda Shaker , Luke A. Prendergast

In this paper, we propose two algorithms for solving linear inverse problems when the observations are corrupted by noise. A proper data fidelity term (log-likelihood) is introduced to reflect the statistics of the noise (e.g. Gaussian,…

Applications · Statistics 2011-03-14 François-Xavier Dupé , Jalal Fadili , Jean-Luc Starck

Least squares (LS) fitting is one of the most fundamental techniques in science and engineering. It is used to estimate parameters from multiple noisy observations. In many problems the parameters are known a-priori to be bounded integer…

Information Theory · Computer Science 2009-01-05 Amir Leshem , Jacob Goldberger

The Levenberg-Marquardt algorithm is one of the most popular algorithms for finding the solution of nonlinear least squares problems. Across different modified variations of the basic procedure, the algorithm enjoys global convergence, a…

Optimization and Control · Mathematics 2020-04-08 E. Bergou , Y. Diouane , V. Kungurtsev

The least-mean-squares (LMS) algorithm is the most popular algorithm in adaptive filtering. Several variable step-size strategies have been suggested to improve the performance of the LMS algorithm. These strategies enhance the performance…

Data Structures and Algorithms · Computer Science 2017-03-22 Muhammad Omer Bin Saeed

Randomized matrix compression techniques, such as the Johnson-Lindenstrauss transform, have emerged as an effective and practical way for solving large-scale problems efficiently. With a focus on computational efficiency, however, forsaking…

Machine Learning · Statistics 2015-10-19 Stephen Becker , Ban Kawas , Marek Petrik , Karthikeyan N. Ramamurthy

Iteratively reweighted least square (IRLS) is a popular approach to solve sparsity-enforcing regression problems in machine learning. State of the art approaches are more efficient but typically rely on specific coordinate pruning schemes.…

Machine Learning · Statistics 2022-10-03 Clarice Poon , Gabriel Peyré