Abstract

Introducing a suitable variational formulation for the local error of scattered data interpolation by radial basis functions OE(r), the error can be bounded by a term depending on the Fourier transform of the interpolated function f and a certain "Kriging function", which allows a formulation as an integral involving the Fourier transform of OE. The explicit construction of locally well--behaving admissible coefficient vectors makes the Kriging function bounded by some power of the local density h of data points. This leads to error estimates for interpolation of functions f whose Fourier transform f is "dominated" by the nonnegative Fourier transform / of /(x) = OE(kxk) in the sense R j f j 2 / \Gamma1 dt ! 1. Approximation orders are arbitrarily high for interpolation with Hardy multiquadrics, inverse multiquadrics and Gaussian kernels. This was also proven in recent papers by Madych and Nelson, using a reproducing kernel Hilbert space approach and requiring the same h...

Citations