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Related papers: Greedy capped nonlinear Kaczmarz methods

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Randomized Kaczmarz methods form a family of linear system solvers which converge by repeatedly projecting their iterates onto randomly sampled equations. While effective in some contexts, such as highly over-determined least squares,…

Numerical Analysis · Mathematics 2025-07-30 Michał Dereziński , Deanna Needell , Elizaveta Rebrova , Jiaming Yang

Motivated by, e.g., sensitivity analysis and end-to-end learning, the demand for differentiable optimization algorithms has been significantly increasing. In this paper, we establish a theoretically guaranteed versatile framework that makes…

Data Structures and Algorithms · Computer Science 2020-06-15 Shinsaku Sakaue

We investigate the randomized Kaczmarz method that adaptively updates the stepsize using readily available information for solving inconsistent linear systems. A novel geometric interpretation is provided which shows that the proposed…

Numerical Analysis · Mathematics 2023-03-17 Yun Zeng , Deren Han , Yansheng Su , Jiaxin Xie

We connect high-dimensional subset selection and submodular maximization. Our results extend the work of Das and Kempe (2011) from the setting of linear regression to arbitrary objective functions. For greedy feature selection, this…

Machine Learning · Statistics 2017-10-13 Ethan R. Elenberg , Rajiv Khanna , Alexandros G. Dimakis , Sahand Negahban

In this paper, we consider a subset selection problem in a spatial field where we seek to find a set of k locations whose observations provide the best estimate of the field value at a finite set of prediction locations. The measurements…

Optimization and Control · Mathematics 2022-04-12 Shamak Dutta , Nils Wilde , Stephen L. Smith

We study submodular maximization problems with matroid constraints, in particular, problems where the objective can be expressed via compositions of analytic and multilinear functions. We show that for functions of this form, the so-called…

Machine Learning · Computer Science 2024-12-17 Gözde Özcan , Armin Moharrer , Stratis Ioannidis

We present a first step towards a multigrid method for solving the min-cost flow problem. Specifically, we present a strategy that takes advantage of existing black-box fast iterative linear solvers, i.e. algebraic multigrid methods. We…

Optimization and Control · Mathematics 2016-12-02 Alessio Quaglino , Rolf Krause

We present a new method for performing nonlinear approximation with redundant dictionaries. The method constructs an $m-$term approximation of the signal by thresholding with respect to a weighted version of its canonical expansion…

Functional Analysis · Mathematics 2017-11-07 Emil Solsbæk Ottosen , Morten Nielsen

We investigate the performance of the standard Greedy algorithm for cardinality constrained maximization of non-submodular nondecreasing set functions. While there are strong theoretical guarantees on the performance of Greedy for…

Discrete Mathematics · Computer Science 2019-05-15 Andrew An Bian , Joachim M. Buhmann , Andreas Krause , Sebastian Tschiatschek

In this paper, we propose a catalog of iterative methods for solving the Split Feasibility Problem in the non-convex setting. We study four different optimization formulations of the problem, where each model has advantageous in different…

Optimization and Control · Mathematics 2020-10-12 Aviv Gibali , Shoham Sabach , Sergey Voldman

This paper proposes a new algorithm for multiple sparse regression in high dimensions, where the task is to estimate the support and values of several (typically related) sparse vectors from a few noisy linear measurements. Our algorithm is…

Machine Learning · Statistics 2012-06-08 Ali Jalali , Sujay Sanghavi

We consider a wide class of the discrete optimization problems with interval objective function. We give a generalization of the greedy algorithm for the problems. Using the algorithm, we obtain the set of all possible greedy solutions and…

Data Structures and Algorithms · Computer Science 2020-09-29 Alexander Prolubnikov

Many algorithms for maximizing a monotone submodular function subject to a knapsack constraint rely on the natural greedy heuristic. We present a novel refined analysis of this greedy heuristic which enables us to: $(1)$ reduce the…

Data Structures and Algorithms · Computer Science 2021-03-16 Ariel Kulik , Roy Schwartz , Hadas Shachnai

In this paper, we study the non-monotone adaptive submodular maximization problem subject to a cardinality constraint. We first revisit the adaptive random greedy algorithm proposed in \citep{gotovos2015non}, where they show that this…

Machine Learning · Computer Science 2020-12-16 Shaojie Tang

We present an enhanced version of the row-based randomized block-Kaczmarz method to solve a linear system of equations. This improvement makes use of a regularization during block updates in the solution, and a dynamic proposal distribution…

Numerical Analysis · Mathematics 2025-10-03 Suvendu Kar , Murugesan Venkatapathi

The randomized Kaczmarz method and its accelerated variants are a powerful class of iterative methods for solving large-scale linear systems, offering guaranteed convergence with low per-iteration cost. However, their numerical stability…

Numerical Analysis · Mathematics 2026-05-19 Michał Dereziński , Ethan N. Epperly , Deanna Needell , Alexander Xue

In [25], T. Oikhberg introduced and studied variants of the greedy and weak greedy algorithms for sequences with gaps, with a focus on the $\mathbf n$-$t$-quasi-greedy property that is based on them. Building upon this foundation, our…

Functional Analysis · Mathematics 2023-09-04 Miguel Berasategui , Pablo M. Berná

We investigate modified steepest descent methods coupled with a loping Kaczmarz strategy for obtaining stable solutions of nonlinear systems of ill-posed operator equations. We show that the proposed method is a convergent regularization…

Numerical Analysis · Mathematics 2008-08-03 A. De Cezaro , M. Haltmeier , A. Leitao , O. Scherzer

In this paper, based on an optimization problem, a sketch-and-project method for solving the linear matrix equation AXB = C is proposed. We provide a thorough convergence analysis for the new method and derive a lower bound on the…

Numerical Analysis · Mathematics 2023-06-07 Wendi Bao , Zhiwei Guo , Weiguo Li , Ying Lv , Jichao Wang

Structural parameters of graph (such as degeneracy and arboricity) had rarely been considered when designing algorithms for $\textit{(edge) clique cover}$ problems. Taking degeneracy of graph into account, we present a greedy framework and…

Data Structures and Algorithms · Computer Science 2022-09-07 Ahammed Ullah