76 citations · 343 across the 42 of their papers we have counts for
6 papers · 1 filter
Hyperbolic wavelet analysis of classical isotropic and anisotropic Besov-Sobolev spaces
M. Schäfer, T. Ullrich, B. Vedel
In this paper we introduce new function spaces which we call anisotropic hyperbolic Besov and Triebel-Lizorkin spaces. Their definition is based on a hyperbolic Littlewood-Paley an…
A higher order Faber spline basis for sampling discretization of functions
Nadiia Derevianko, Tino Ullrich
This paper is devoted to the question of constructing a higher order Faber spline basis for the sampling discretization of functions with higher regularity than Lipschitz. The basi…
Worst-case recovery guarantees for least squares approximation using random samples
Lutz Kämmerer, Tino Ullrich, Toni Volkmer
We construct a least squares approximation method for the recovery of complex-valued functions from a reproducing kernel Hilbert space on . The nodes are dr…
The Haar System in Triebel-Lizorkin Spaces: Endpoint Results
Gustavo Garrigós, Andreas Seeger, Tino Ullrich
We characterize the Schauder and unconditional basis properties for the Haar system in the Triebel-Lizorkin spaces , at the endpoint cases , and…
Entropy numbers of finite dimensional mixed-norm balls and function space embeddings with small mixed smoothness
Sebastian Mayer, Tino Ullrich
We study the embedding and prove matching bounds for the entropy numbers provided that an…
Basis properties of the Haar system in limiting Besov spaces
Gustavo Garrigós, Andreas Seeger, Tino Ullrich
We study Schauder basis properties for the Haar system in Besov spaces . We give a complete description of the limiting cases, obtaining various positive r…