Positive Definite Functions on Hilbert Space
نویسنده
چکیده
is always non-negative, for any positive integer n and all points x1, . . . , xn in H is said to be positive definite on Hilbert space. In Schoenberg (1938), it was shown that a function is positive definite on Hilbert space if and only if it is completely monotonic, and this characterization is of central importance in the theory of radial basis functions and learning theory. In this paper, we present a short geometric proof of this beautiful fact.
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تاریخ انتشار 2003