English

The representer theorem for Hilbert spaces: a necessary and sufficient condition

Functional Analysis 2012-07-18 v3 Machine Learning

Abstract

A family of regularization functionals is said to admit a linear representer theorem if every member of the family admits minimizers that lie in a fixed finite dimensional subspace. A recent characterization states that a general class of regularization functionals with differentiable regularizer admits a linear representer theorem if and only if the regularization term is a non-decreasing function of the norm. In this report, we improve over such result by replacing the differentiability assumption with lower semi-continuity and deriving a proof that is independent of the dimensionality of the space.

Keywords

Cite

@article{arxiv.1205.1928,
  title  = {The representer theorem for Hilbert spaces: a necessary and sufficient condition},
  author = {Francesco Dinuzzo and Bernhard Schölkopf},
  journal= {arXiv preprint arXiv:1205.1928},
  year   = {2012}
}
R2 v1 2026-06-21T21:00:42.184Z