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An increasing sequence $(x_i)_{i=1}^n$ of positive integers is an $n$-term Egyptian underapproximation of $\theta \in (0,1]$ if $\sum_{i=1}^n \frac{1}{x_i} < \theta$. A greedy algorithm constructs an $n$-term underapproximation of $\theta$.…

Number Theory · Mathematics 2022-12-14 Melvyn B. Nathanson

Reduced order models, in particular the reduced basis method, rely on empirically built and problem dependent basis functions that are constructed during an off-line stage. In the on-line stage, the precomputed problem-dependent solution…

Numerical Analysis · Mathematics 2012-12-07 Yvon Maday , Benjamin Stamm

We briefly discuss the greedy method and a couple of its more efficient variants for approximately maximizing monotone submodular functions.

Optimization and Control · Mathematics 2025-10-21 Alen Alexanderian

We consider finite element solutions to quadratic optimization problems, where the state depends on the control via a well-posed linear partial differential equation. Exploiting the structure of a suitably reduced optimality system, we…

Numerical Analysis · Mathematics 2019-10-03 Fernando Gaspoz , Christian Kreuzer , Andreas Veeser , Winnifried Wollner

We consider a general task called partial Wasserstein covering with the goal of providing information on what patterns are not being taken into account in a dataset (e.g., dataset used during development) compared with another dataset(e.g.,…

Machine Learning · Computer Science 2021-12-09 Keisuke Kawano , Satoshi Koide , Keisuke Otaki

In this work, we consider the maximization of submodular functions constrained by independence systems. Because of the wide applicability of submodular functions, this problem has been extensively studied in the literature, on specialized…

Data Structures and Algorithms · Computer Science 2019-06-11 Alan Kuhnle

We show that the greedy algorithm for adaptive-submodular cover has approximation ratio at least 1.3*(1+ln Q). Moreover, the instance demonstrating this gap has Q=1. So, it invalidates a prior result in the paper ``Adaptive Submodularity: A…

Data Structures and Algorithms · Computer Science 2024-05-27 Blake Harris , Viswanath Nagarajan

We generalize several theorems of R\'enyi, Parry, Dar\'oczy and K\'atai by characterizing the greedy and quasi-greedy expansions in non-integer bases.

Number Theory · Mathematics 2007-10-17 Claudio Baiocchi , Vilmos Komornik

Submodular function maximization finds application in a variety of real-world decision-making problems. However, most existing methods, based on greedy maximization, assume it is computationally feasible to evaluate F, the function being…

Artificial Intelligence · Computer Science 2020-08-11 Yash Satsangi , Shimon Whiteson , Frans A. Oliehoek

We prove that for any two quasi-Banach spaces $X$ and $Y$ and any $\alpha>0$ there exists a constant $\gamma_\alpha>0$ such that $$ \sup_{1\le k\le n}k^{\alpha}e_k(T)\le \gamma_\alpha \sup_{1\le k\le n} k^\alpha c_k(T) $$ holds for all…

Functional Analysis · Mathematics 2016-05-24 Aicke Hinrichs , Anton Kolleck , Jan Vybiral

The seminar assignment problem is a variant of the generalized assignment problem in which items have unit size and the amount of space allowed in each bin is restricted to an arbitrary set of values. The problem has been shown to be…

Data Structures and Algorithms · Computer Science 2016-10-18 Amotz Bar-Noy , George Rabanca

Monotone submodular maximization with a knapsack constraint is NP-hard. Various approximation algorithms have been devised to address this optimization problem. In this paper, we revisit the widely known modified greedy algorithm. First, we…

Data Structures and Algorithms · Computer Science 2021-01-14 Jing Tang , Xueyan Tang , Andrew Lim , Kai Han , Chongshou Li , Junsong Yuan

Garling sequence spaces admit a renorming with respect to which their standard unit vector basis is 1-greedy. We also discuss some additional properties of these Banach spaces related to uniform convexity and superreflexivity. In…

Functional Analysis · Mathematics 2017-05-12 Fernado Albiac , José L. Ansorena , Ben Wallis

We investigate the problem of improving the greedy-type constant of a basis by means of an equivalent renorming of the ambient Banach space. Our main result shows that if a Banach space admits an unconditional and bidemocratic basis whose…

Functional Analysis · Mathematics 2026-03-24 Fernando Albiac , José L. Ansorena , Miguel Berasategui , Pablo M. Berná

We discuss the upper and lower estimates for the rate of convergence of Pure and Orthogonal Greedy Algorithms for dictionary with bounded cumulative coherence.

Numerical Analysis · Mathematics 2009-11-10 Eugene Livshitz

Our aim is to investigate the properties of existence and uniqueness of greedy bases in Banach spaces. We show the non-existence of greedy basis in some Nakano spaces and Orlicz sequence spaces and produce the first-known examples of…

Functional Analysis · Mathematics 2015-06-01 F. Albiac , J. L. Ansorena , S. J. Dilworth , Denka Kutzarova

Kernel-based schemes are state-of-the-art techniques for learning by data. In this work we extend some ideas about kernel-based greedy algorithms to exponential-polynomial splines, whose main drawback consists in possible overfitting and…

Numerical Analysis · Mathematics 2022-10-31 Rosanna Campagna , Stefano De Marchi , Emma Perracchione , Gabriele Santin

We establish inverse and direct theorems on best approximations in quasi-normed Abelian groups through bilateral Bernstein-Jackson inequalities with exact constants. Using integral representations for quasi-norms of functions $f$ in…

Functional Analysis · Mathematics 2024-10-22 Oleh Lopushansky

We study the problem of causal structure learning when the experimenter is limited to perform at most $k$ non-adaptive experiments of size $1$. We formulate the problem of finding the best intervention target set as an optimization problem,…

Machine Learning · Computer Science 2018-08-03 AmirEmad Ghassami , Saber Salehkaleybar , Negar Kiyavash , Elias Bareinboim

We study minimum entropy submodular optimization, a common generalization of the minimum entropy set cover problem, studied earlier by Cardinal et al., and the submodular set cover problem. We give a general bound of the approximation…

Data Structures and Algorithms · Computer Science 2014-02-19 Cosmin Bonchiş , Gabriel Istrate