Sampling-based Nystr\"om Approximation and Kernel Quadrature
- URL: http://arxiv.org/abs/2301.09517v3
- Date: Tue, 23 May 2023 01:18:39 GMT
- Title: Sampling-based Nystr\"om Approximation and Kernel Quadrature
- Authors: Satoshi Hayakawa, Harald Oberhauser, Terry Lyons
- Abstract summary: We analyze the Nystr"om approximation of a positive definite kernel associated with a probability measure.
We first prove an improved error bound for the conventional Nystr"om approximation with i.i.d. sampling and singular-value decomposition.
We then introduce a refined selection of subspaces in Nystr"om approximation with theoretical guarantees that is applicable to non-i.i.d. landmark points.
- Score: 8.658596218544774
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: We analyze the Nystr\"om approximation of a positive definite kernel
associated with a probability measure. We first prove an improved error bound
for the conventional Nystr\"om approximation with i.i.d. sampling and
singular-value decomposition in the continuous regime; the proof techniques are
borrowed from statistical learning theory. We further introduce a refined
selection of subspaces in Nystr\"om approximation with theoretical guarantees
that is applicable to non-i.i.d. landmark points. Finally, we discuss their
application to convex kernel quadrature and give novel theoretical guarantees
as well as numerical observations.
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