Search Results - "thresholding greedy algorithm"

The thresholding greedy algorithm versus approximations with sizes bounded by certain functions f by Chu, Hùng Việt

“…Let X be a Banach space and (en)n=1∞ be a basis. For a function f in a large collection F (closed under composition), we define and characterize f-greedy and…”
Get full text

Elton's near unconditionality of bases as a threshold-free form of greediness by Albiac, Fernando, Ansorena, José L., Berasategui, Miguel

“…Elton's near unconditionality and quasi-greediness for largest coefficients are two properties of bases that made their appearance in functional analysis from…”
Get full text

Linear versus nonlinear forms of partial unconditionality of bases by Albiac, Fernando, Ansorena, José L., Berasategui, Miguel

“…The main results in this paper contribute to bringing to the fore novel underlying connections between the contemporary concepts and methods springing from…”
Get full text

Twenty-five years of greedy bases by Albiac, Fernando, Ansorena, José L., Temlyakov, Vladimir

“…Although the basic idea behind the concept of a greedy basis had been around for some time, the formal development of a theory of greedy bases was initiated in…”
Get full text

Counterexamples in isometric theory of symmetric and greedy bases by Albiac, Fernando, Ansorena, José L., Blasco, Óscar, Chu, Hùng Việt, Oikhberg, Timur

“…We continue the study initiated in Albiac and Wojtaszczyk (2006) of properties related to greedy bases in the case when the constants involved are sharp, i.e.,…”
Get full text

Bidemocratic Bases and Their Connections with Other Greedy-Type Bases by Albiac, Fernando, Ansorena, José L., Berasategui, Miguel, Berná, Pablo M., Lassalle, Silvia

“…In nonlinear greedy approximation theory, bidemocratic bases have traditionally played the role of dualizing democratic, greedy, quasi-greedy, or almost greedy…”
Get full text

On some characterizations of greedy-type bases by Berná, Pablo M., Chu, Hùng Việt

“…In 1999, S. V. Konyagin and V. N. Temlyakov introduced the so-called Thresholding Greedy Algorithm. Since then, there have been many interesting and useful…”
Get full text

Characterization of 1-quasi-greedy bases by Albiac, F., Ansorena, J.L.

“…In this note we continue the study initiated in Albiac and Wojtaszczyk (2006) of greedy-like bases in the “isometric case”, i.e., in the case that the…”
Get full text

Characterization of greedy bases in Banach spaces by Berná, Pablo M., Blasco, Óscar

“…We shall present a new characterization of greedy bases and 1-greedy bases in terms of certain functionals defined using distances to one dimensional subspaces…”
Get full text

Existence of Almost Greedy Bases in Mixed-Norm Sequence and Matrix Spaces, Including Besov Spaces by Albiac, Fernando, Ansorena, José L., Bello, Glenier, Wojtaszczyk, Przemysław

“…We prove that the sequence spaces ℓ p ⊕ ℓ q and the spaces of infinite matrices ℓ p ( ℓ q ) , ℓ q ( ℓ p ) and ( ⨁ n = 1 ∞ ℓ p n ) ℓ q , which are isomorphic to…”
Get full text

On sequential greedy-type bases: On sequential greedy-type bases by Berasategui, Miguel, Berná, Pablo M., Chu, Hùng Việt

“…It is known that a basis is almost greedy if and only if the thresholding greedy algorithm gives essentially the smallest error term compared to errors from…”
Get full text

On approximation spaces and Greedy-type bases by Berná, Pablo M., Chu, Hùng Việt, Hernández, Eugenio

“…The purpose of this paper is to introduce ω -Chebyshev–Greedy and ω -partially greedy approximation classes and study their relation with ω -approximation…”
Get full text

Lebesgue inequalities for the greedy algorithm in general bases by Berná, Pablo M., Blasco, Óscar, Garrigós, Gustavo

“…We present various estimates for the Lebesgue type inequalities associated with the thresholding greedy algorithm, in the case of general bases in Banach…”
Get full text

On Weighted Greedy-Type Bases by Chu, Hùng Việt

“…We study weights for the thresholding greedy algorithm, aiming to extend previous work on sequential weights ς on N to weights ω on P ( N ) . We revisit major…”
Get full text

Characterization of 1-almost greedy bases by Albiac, F., Ansorena, J. L.

“…This article closes the cycle of characterizations of greedy-like bases in the “isometric” case initiated in Albiac and Wojtaszczyk (J. Approx. Theory…”
Get full text

On consecutive greedy and other greedy-like type of bases by Berasategui, Miguel, Berná, Pablo M., Chu, Hùng Việt

“…We continue our study of the thresholding greedy algorithm when we restrict the vectors involved in our approximations so that they either are supported on…”
Get full text

Conditional Quasi-Greedy Bases in Non-superreflexive Banach Spaces by Albiac, Fernando, Ansorena, José L., Wojtaszczyk, Przemysław

“…For a conditional quasi-greedy basis B in a Banach space, the associated conditionality constants k m [ B ] verify the estimate k m [ B ] = O ( log m ) …”
Get full text

Characterization of Weight-Semi-greedy Bases by Berná, Pablo Manuel

“…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…”
Get full text

Lebesgue inequalities for Chebyshev thresholding greedy algorithms by Berná, P. M., Blasco, Ó., Garrigós, G., Hernández, E., Oikhberg, T.

“…We establish estimates for the Lebesgue parameters of the Chebyshev weak thresholding greedy algorithm in the case of general bases in Banach spaces. These…”
Get full text

Lebesgue-Type Inequalities for Quasi-greedy Bases by Garrigós, Gustavo, Hernández, Eugenio, Oikhberg, Timur

“…We show that, for quasi-greedy bases in real or complex Banach spaces, an optimal bound for the ratio between greedy N -term approximation ∥ x − G N x ∥ and…”
Get full text