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Related papers: Lebesgue-type inequalities in greedy approximation

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Motivated by recent work on stochastic gradient descent methods, we develop two stochastic variants of greedy algorithms for possibly non-convex optimization problems with sparsity constraints. We prove linear convergence in expectation to…

Numerical Analysis · Mathematics 2014-07-02 Nam Nguyen , Deanna Needell , Tina Woolf

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

In this paper we study a new class of bases, weaker than quasi-greedy bases, which retain their unconditionality properties and can provide the same optimality for the thresholding greedy algorithm. We measure how far these bases are from…

Functional Analysis · Mathematics 2021-06-03 Fernando Albiac , Jose L. Ansorena , Miguel Berasategui , Pablo M. Berna , Silvia Lassalle

We give a new decay framework for general dissipative hyperbolic system and hyperbolic-parabolic composite system, which allow us to pay less attention on the traditional spectral analysis in comparison with previous efforts. New…

Analysis of PDEs · Mathematics 2015-03-17 Jiang Xu , Shuichi Kawashima

In this paper we show that that greedy bases can be defined as those where the error term using $m$-greedy approximant is uniformly bounded by the best $m$-term approximation with respect to polynomials with constant coefficients in the…

Functional Analysis · Mathematics 2016-06-24 Pablo M. Berná , Óscar Blasco

In this paper we present and prove some new results concerning approximation properties of $T$ means with respect to the Vilenkin system in Lebesgue spaces and Lipschitz classes for any $1\leq p<\infty$. As applications, we obtain extension…

General Mathematics · Mathematics 2024-05-31 N. Anakidze , N. Areshidze , L. -E. Persson , G. Tephnadze

We suggest a new greedy strategy for convex optimization in Banach spaces and prove its convergent rates under a suitable behavior of the modulus of uniform smoothness of the objective function.

Optimization and Control · Mathematics 2015-05-15 Zheming Gao , Guergana Petrova

In this article we obtain the non - asymptotical low estimations for bilinear Riesz's functional through the Lebesgue spaces norms by means of building of some examples.

Functional Analysis · Mathematics 2009-10-01 E. Ostrovsky L. Sirota

In this paper we introduce some new weighted maximal operators of the partial sums of the Walsh-Fourier series. We prove that for some "optimal" weights these new operators indeed are bounded from the martingale Hardy space $H_{p}$ to the…

General Mathematics · Mathematics 2023-08-03 David Baramidze , Lars-Erik Persson , Harpal Singh , George Tephnadze

We analyze greedy algorithms for the Hierarchical Aggregation (HAG) problem, a strategy introduced in [Jia et al., KDD 2020] for speeding up learning on Graph Neural Networks (GNNs). The idea of HAG is to identify and remove redundancies in…

Data Structures and Algorithms · Computer Science 2021-02-09 Alexandra Porter , Mary Wootters

One classical result in greedy approximation theory is that almost-greedy and semi-greedy bases are equivalent in the context of Schauder bases in Banach spaces with finite cotype. This result was proved by S. J. Dilworth, N. J. Kalton and…

Functional Analysis · Mathematics 2019-03-01 Pablo M. Berná

In this paper we obtain quantitative weighted $L^p$-inequalities for some operators involving Bessel convolutions. We consider maximal operators, Littlewood-Paley functions and variational operators. We obtain $L^p(w)$-operator norms in…

Classical Analysis and ODEs · Mathematics 2021-10-06 Víctor Almeida , Jorge J. Betancor , Juan C. Fariña , Lourdes Rodríguez-Mesa

In the context of Gaussian conditioning, greedy algorithms iteratively select the most informative measurements, given an observed Gaussian random variable. However, the convergence analysis for conditioning Gaussian random variables…

Statistics Theory · Mathematics 2025-02-18 Daniel Winkle , Ingo Steinwart , Bernard Haasdonk

In this paper, the author establishes the boundedness of parametric Littlewood-Paley operators from Musielak-Orlicz Hardy space to Musielak-Orlicz space, or to weak Musielak-Orlicz space at the critical index. Part of these results are new…

Classical Analysis and ODEs · Mathematics 2017-11-29 Bo Li

We present new estimate for Hardy-type inequality in variable exponent Lebesgue spaces. More precisely, by imposing regularity assumptions on the exponent, we prove that the estimations can be reduced to the fixed exponents.

Functional Analysis · Mathematics 2017-03-09 Douadi Drihem

Greedy expansions with prescribed coefficients have been introduced by V. N. Temlyakov in the frame of Banach spaces. The idea is to choose a sequence of fixed (real) coefficients $\{c_n\}_{n=1}^\infty$ and a fixed set of elements…

Functional Analysis · Mathematics 2023-07-06 Alessandro Oliaro , Luca Tomatis , Albert R. Valiullin , Artur R. Valiullin

The paper presents a priori error analysis of the shallow neural network approximation to the solution to the indefinite elliptic equation and and cutting-edge implementation of the Orthogonal Greedy Algorithm (OGA) tailored to overcome the…

Numerical Analysis · Mathematics 2024-10-28 Qingguo Hong , Jiwei Jia , Young Ju Lee , Ziqian Li

We analyze the orthogonal greedy algorithm when applied to dictionaries $\mathbb{D}$ whose convex hull has small entropy. We show that if the metric entropy of the convex hull of $\mathbb{D}$ decays at a rate of $O(n^{-\frac{1}{2}-\alpha})$…

Statistics Theory · Mathematics 2022-01-25 Jonathan W. Siegel , Jinchao Xu

Motivated by the fact that in several cases a matching in a graph is stable if and only if it is produced by a greedy algorithm, we study the problem of computing a maximum weight greedy matching on weighted graphs, termed GreedyMatching.…

Discrete Mathematics · Computer Science 2016-05-23 Argyrios Deligkas , George B. Mertzios , Paul G. Spirakis

In this article, we present a greedy algorithm based on a tensor product decomposition, whose aim is to compute the global minimum of a strongly convex energy functional. We prove the convergence of our method provided that the gradient of…

Functional Analysis · Mathematics 2015-03-13 Eric Cances , Virginie Ehrlacher , Tony Lelievre