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Related papers: Generalized de Branges-Rovnyak spaces

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We consider Hilbert spaces of analytic functions in the disk with a normalized reproducing kernel and such that the backward shift $f(z) \mapsto \frac{f(z)-f(0)}{z}$ is a contraction on the space. We present a model for this operator and…

Functional Analysis · Mathematics 2019-01-15 Alexandru Aleman , Bartosz Malman

We show that there exists a de Branges-Rovnyak space $\mathcal{H}(b)$ on the unit disk containing a function $f$ with the following property: even though $f$ can be approximated by polynomials in $\mathcal{H}(b)$, neither the Taylor partial…

Functional Analysis · Mathematics 2021-09-07 Javad Mashreghi , Pierre-Olivier Parisé , Thomas Ransford

This is a tutorial and survey paper on kernels, kernel methods, and related fields. We start with reviewing the history of kernels in functional analysis and machine learning. Then, Mercer kernel, Hilbert and Banach spaces, Reproducing…

Machine Learning · Statistics 2021-06-17 Benyamin Ghojogh , Ali Ghodsi , Fakhri Karray , Mark Crowley

In this paper we consider the reproducing kernel thesis for boundedness and compactness for various operators on Bergman-type spaces. In particular, the results in this paper apply to the weighted Bergman space on the unit ball, the unit…

Complex Variables · Mathematics 2018-02-09 Mishko Mitkovski , Brett D. Wick

In this paper we consider the reproducing kernel thesis for boundedness and compactness for operators on $\ell^2$--valued Bergman-type spaces. This paper generalizes many well--known results about classical function spaces to their…

Classical Analysis and ODEs · Mathematics 2015-05-21 Robert Rahm

We analyse the convergence of sampling algorithms for functions in reproducing kernel Hilbert spaces (RKHS). To this end, we discuss approximation properties of kernel regression under minimalistic assumptions on both the kernel and the…

Machine Learning · Statistics 2025-04-21 Armin Iske

We characterize the reproducing kernel Hilbert spaces whose elements are $p$-integrable functions in terms of the boundedness of the integral operator whose kernel is the reproducing kernel. Moreover, for $p=2$ we show that the spectral…

Functional Analysis · Mathematics 2007-05-23 Claudio Carmeli , Ernesto De Vito , Alessandro Toigo

We study reproducing kernel Hilbert and Pontryagin spaces of slice hyperholomorphic functions which are analogs of the Hilbert spaces of analytic functions introduced by de Branges and Rovnyak. In the first part of the paper we focus on the…

Functional Analysis · Mathematics 2012-03-02 Daniel Alpay , Fabrizio Colombo , Irene Sabadini

By making a seminal use of the maximum modulus principle of holomorphic functions we prove existence of $n$-best kernel approximation for a wide class of reproducing kernel Hilbert spaces of holomorphic functions in the unit disc, and for…

Complex Variables · Mathematics 2022-01-20 Tao Qian

For $S$ a contractive analytic operator-valued function on the unit disk ${\mathbb D}$, de Branges and Rovnyak associate a Hilbert space of analytic functions ${\mathcal H}(S)$. A companion survey provides equivalent definitions and basic…

Classical Analysis and ODEs · Mathematics 2014-05-14 Joseph A. Ball , Vladimir Bolotnikov

There exists a plethora of parametric models for positive definite kernels, and their use is ubiquitous in disciplines as diverse as statistics, machine learning, numerical analysis, and approximation theory. Usually, the kernel parameters…

Machine Learning · Statistics 2025-01-06 Xavier Emery , Emilio Porcu , Moreno Bevilacqua

We consider de Branges-Rovnyak spaces of a considerably large class of reproducing kernel Hilbert spaces and find a characterization for them to be complete Nevanlinna-Pick spaces. This extends as well as recovers earlier characterizations…

Functional Analysis · Mathematics 2025-08-08 Hamidul Ahmed , B. Krishna Das , Samir Panja

This note consists of two largely independent parts. In the first part we give conditions on the kernel $k: \Omega \times \Omega \rightarrow \mathbb{R}$ of a reproducing kernel Hilbert space $H$ continuously embedded via the identity…

Functional Analysis · Mathematics 2022-06-16 Marcin Wnuk

We present decompositions of various positive kernels as integrals or sums of positive kernels. Within this framework we study the reproducing kernel Hilbert spaces associated with the fractional and bi-fractional Brownian motions. As a…

Probability · Mathematics 2007-05-23 Daniel Alpay , David Levanony

We study reproducing kernel Hilbert spaces introduced as ranges of generalized Ces\`aro-Hardy operators, in one real variable and in one complex variable. Such spaces can be seen as formed by absolutely continuous functions on the positive…

Functional Analysis · Mathematics 2024-01-30 José E. Galé , Pedro J. Miana , Luis Sánchez--Lajustici

In this paper we introduce a generalization of the classical $\Leb_2(\Rd)$-based Sobolev spaces with the help of a vector differential operator $\mathbf{P}$ which consists of finitely or countably many differential operators $P_n$ which…

Numerical Analysis · Mathematics 2011-09-02 Qi Ye

In this paper we deal with a scale of reproducing kernel Hilbert spaces $H^{(n)}_2$, $n\ge 0$, which are linear subspaces of the classical Hilbertian Hardy space on the right-hand half-plane $\mathbb{C}^+$. They are obtained as ranges of…

Functional Analysis · Mathematics 2024-01-30 José E. Galé , Valentin Matache , Pedro J. Miana , Luis Sánchez--Lajusticia

In the Clifford algebra setting the present study develops three reproducing kernel Hilbert spaces of the Paley-Wiener type, namely the Paley-Wiener spaces, the Hardy spaces on strips, and the Bergman spaces on strips. In particular, we…

Complex Variables · Mathematics 2021-08-31 Pei Dang , Weixiong Mai , Tao Qian

In this paper we give an explicit description of de Branges-Rovnyak spaces $\HH(b)$ when $b$ is of the form $q^{r}$, where $q$ is a rational outer function in the closed unit ball of $H^{\infty}$ and $r$ is a positive number.

Complex Variables · Mathematics 2014-06-26 Emmanuel Fricain , Andreas Hartmann , William T. Ross

This article studies the problem of approximating functions belonging to a Hilbert space $\mathcal H_d$ with a reproducing kernel of the form $$\tilde K_d(\boldsymbol x,\boldsymbol t):=\prod_{\ell=1}^d…

Numerical Analysis · Mathematics 2014-11-05 Xuan Zhou , Fred J. Hickernell