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Related papers: Conditionally strictly negative definite kernels

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A class of negative definite kernels is defined in terms of measure spaces. Using this concept, property (T) for a countable group $\G$ is characterized in terms of measure preserving actions of $\G$, as follows. If a set $S$ is translated…

Functional Analysis · Mathematics 2013-02-26 Guyan Robertson , Tim Steger

The paper studies strictly positive definite kernels on compact Riemannian manifolds. We state new conditions to ensure strict positive definiteness for general kernels and kernels with certain convolutional structure. We also state…

Numerical Analysis · Mathematics 2023-01-20 Jean Carlo Guella , Janin Jäger

We investigate the notion of conditionally positive definite in the context of Hilbert $C^*$-modules and present a characterization of the conditionally positive definiteness in terms of the usual positive definiteness. We give a Kolmogorov…

Operator Algebras · Mathematics 2017-09-26 Mohammad Sal Moslehian

For the real, continuous, isotropic and positive definite kernels on a product of spheres, one may consider not only its usual strict positive definiteness but also strict positive definiteness restrict to the points of the product that…

Classical Analysis and ODEs · Mathematics 2015-05-15 Jean C. Guella , Valdir A. Menegatto

We present new classes of positive definite kernels on non-standard spaces that are integrally strictly positive definite or characteristic. In particular, we discuss radial kernels on separable Hilbert spaces, and introduce broad classes…

Machine Learning · Statistics 2022-06-16 Johanna Ziegel , David Ginsbourger , Lutz Dümbgen

We study classes of reproducing kernels $K$ on general domains; these are kernels which arise commonly in machine learning models; models based on certain families of reproducing kernel Hilbert spaces. They are the positive definite kernels…

Functional Analysis · Mathematics 2017-08-22 Palle Jorgensen , Feng Tian

The paper introduces new sufficient conditions of strict positive definiteness for kernels on d-dimensional spheres which are not radially symmetric but possess specific coefficient structures. The results use the series expansion of the…

Numerical Analysis · Mathematics 2021-05-07 Martin Buhmann , Janin Jäger

The paper introduces a new characterisation of strictly positive definiteness for kernels on the 2-sphere without assuming the kernel to be radially (isotropic) or axially symmetric. The results use the series expansion of the kernel in…

Numerical Analysis · Mathematics 2022-05-06 Janin Jäger

We consider a kernel based harmonic analysis of "boundary," and boundary representations. Our setting is general: certain classes of positive definite kernels. Our theorems extend (and are motivated by) results and notions from classical…

Functional Analysis · Mathematics 2016-11-15 Palle Jorgensen , Feng Tian

We supply a Fourier characterization for the real, continuous, isotropic and strictly positive definite kernels on a product of circles.

Classical Analysis and ODEs · Mathematics 2018-09-25 J. C. Guella , V. A. Menegatto , A. P. Peron

This survey is an introduction to positive definite kernels and the set of methods they have inspired in the machine learning literature, namely kernel methods. We first discuss some properties of positive definite kernels as well as…

Machine Learning · Statistics 2009-12-04 Marco Cuturi

We present, among other things, a necessary and sufficient condition for the strict positive definiteness of an isotropic and positive definite kernel on the cartesian product of a circle and a higher dimensional sphere. The result…

Classical Analysis and ODEs · Mathematics 2016-10-31 Jean C. Guella , Valdir A. Menegatto , Ana P. Peron

We provide a characterization for the continuous positive definite kernels on $\mathbb R^d$ that are invariant to linear isometries, i.e. invariant under the orthogonal group $O(d)$. Furthermore, we provide necessary and sufficient…

Statistics Theory · Mathematics 2025-06-30 Felix Benning , Max David Schölpple

For two continuous and isotropic positive definite kernels on the same compact two-point homogeneous space, we determine necessary and sufficient conditions in order that their product be strictly positive definite. We also provide a…

Classical Analysis and ODEs · Mathematics 2018-10-17 Rafaela N. Bonfim , Jean C. Guella , Valdir A. Menegatto

We present an explicit characterization for the real, continuous, isotropic and strictly positive definite kernels on a product of compact two-point homogeneous spaces, in the cases in which at least one of the spaces is a sphere of…

Functional Analysis · Mathematics 2016-05-24 V. S. Barbosa , V. A. Menegatto

We consider the sequence of powers of a positive definite function on a discrete group. Taking inspiration from random walks on compact quantum groups, we give several examples of situations where a cut-off phenomenon occurs for this…

Group Theory · Mathematics 2021-07-01 Amaury Freslon

We present sufficient condition for a family of positive definite kernels on a compact two-point homogeneous space to be strictly positive definite based on their representation as a series of spherical harmonics. The family analyzed is a…

Classical Analysis and ODEs · Mathematics 2022-05-17 Jean Carlo Guella , Janin Jäger

In this paper we extensively investigate the class of conditionally positive definite operators, namely operators generating conditionally positive definite sequences. This class itself contains subnormal operators, $2$- and $3$-isometries…

Functional Analysis · Mathematics 2022-01-26 Zenon Jan Jabłoński , Il Bong Jung , Jan Stochel

Given a fixed sigma-finite measure space $\left(X,\mathscr{B},\nu\right)$, we shall study an associated family of positive definite kernels $K$. Their factorizations will be studied with view to their role as covariance kernels of a variety…

Spectral Theory · Mathematics 2018-10-31 Palle Jorgensen , Feng Tian

We study positive definiteness of kernels $K(x,y)$ on two-point homogeneous spaces. As opposed to the classical case, which has been developed and studied in the existing literature, we allow the kernel to have an (integrable) singularity…

Classical Analysis and ODEs · Mathematics 2024-10-30 Dmitriy Bilyk , Peter Grabner
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