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Title: A Two-Moment Inequality with Applications to Rényi Entropy and Mutual Information
This paper explores some applications of a two-moment inequality for the integral of the rth power of a function, where 0<1. The first contribution is an upper bound on the Rényi entropy of a random vector in terms of the two different moments. When one of the moments is the zeroth moment, these bounds recover previous results based on maximum entropy distributions under a single moment constraint. More generally, evaluation of the bound with two carefully chosen nonzero moments can lead to significant improvements with a modest increase in complexity. The second contribution is a method for upper bounding mutual information in terms of certain integrals with respect to the variance of the conditional density. The bounds have a number of useful properties arising from the connection with variance decompositions.  more » « less
Award ID(s):
1750362
PAR ID:
10221391
Author(s) / Creator(s):
Date Published:
Journal Name:
Entropy
Volume:
22
Issue:
11
ISSN:
1099-4300
Page Range / eLocation ID:
1244
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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