The representer theorem for Hilbert spaces: a necessary and sufficient condition
نویسندگان
چکیده
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 semicontinuity and deriving a proof that is independent of the dimensionality of the space.
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تاریخ انتشار 2012