On the Joint Entropy of -Wise-Independent Variables
arXiv:1503.08154
Abstract
How low can the joint entropy of -wise independent (for ) discrete random variables be, subject to given constraints on the individual distributions (say, no value may be taken by a variable with probability greater than , for )? This question has been posed and partially answered in a recent work of Babai. In this paper we improve some of his bounds, prove new bounds in a wider range of parameters and show matching upper bounds in some special cases. In particular, we prove tight lower bounds for the min-entropy (as well as the entropy) of pairwise and three-wise independent balanced binary variables for infinitely many values of .