Schoenberg’s Problem on Positive Definite Functions
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چکیده
منابع مشابه
A Note on Positive Definite Norm Dependent Functions
Let K be an origin symmetric star body in R. We prove, under very mild conditions on the function f : [0,∞) → R, that if the function f(‖x‖K) is positive definite on R , then the space (R, ‖ · ‖K) embeds isometrically in L0. This generalizes the solution to Schoenberg’s problem and leads to progress in characterization of n-dimensional versions, i.e. random vectors X = (X1, ...,Xn) in R n such ...
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