TY - GEN
T1 - Convexity/concavity of renyi entropy and α-mutual information
AU - Ho, Siu Wai
AU - Verdú, Sergio
N1 - Publisher Copyright:
© 2015 IEEE.
PY - 2015/9/28
Y1 - 2015/9/28
N2 - Entropy is well known to be Schur concave on finite alphabets. Recently, the authors have strengthened the result by showing that for any pair of probability distributions P and Q with Q majorized by P, the entropy of Q is larger than the entropy of P by the amount of relative entropy D(P||Q). This result applies to P and Q defined on countable alphabets. This paper shows the counterpart of this result for the Rényi entropy and the Tsallis entropy. Lower bounds on the difference in the Rényi (or Tsallis) entropy are given in terms of a new divergence which is related to the Rényi (or Tsallis) divergence. This paper also considers a notion of generalized mutual information, namely α-mutual information, which is defined through the Rényi divergence. The convexity/concavity for different ranges of α is shown. A sufficient condition for the Schur concavity is discussed and upper bounds on α-mutual information are given in terms of the Rényi entropy.
AB - Entropy is well known to be Schur concave on finite alphabets. Recently, the authors have strengthened the result by showing that for any pair of probability distributions P and Q with Q majorized by P, the entropy of Q is larger than the entropy of P by the amount of relative entropy D(P||Q). This result applies to P and Q defined on countable alphabets. This paper shows the counterpart of this result for the Rényi entropy and the Tsallis entropy. Lower bounds on the difference in the Rényi (or Tsallis) entropy are given in terms of a new divergence which is related to the Rényi (or Tsallis) divergence. This paper also considers a notion of generalized mutual information, namely α-mutual information, which is defined through the Rényi divergence. The convexity/concavity for different ranges of α is shown. A sufficient condition for the Schur concavity is discussed and upper bounds on α-mutual information are given in terms of the Rényi entropy.
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U2 - 10.1109/ISIT.2015.7282554
DO - 10.1109/ISIT.2015.7282554
M3 - Conference contribution
AN - SCOPUS:84969900521
T3 - IEEE International Symposium on Information Theory - Proceedings
SP - 745
EP - 749
BT - Proceedings - 2015 IEEE International Symposium on Information Theory, ISIT 2015
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - IEEE International Symposium on Information Theory, ISIT 2015
Y2 - 14 June 2015 through 19 June 2015
ER -