2025/10/08 by Ding, Ni, Farokhi, Farhad, Guo, Tao +2
#FOS: Computer and information sciences #Information Theory (cs.IT)
paper · doi:10.48550/arxiv.2510.06622
For f(t) = exp(\fracα-1αt), this paper shows that the Sibson mutual information is an α-leakage averaged over the adversary's f-mean relative information gain (on the secret) at elementary event of channel output Y as well as the joint occurrence of elementary channel input X and output Y. This interpretation is used to derive a sufficient condition that achieves a δ-approximation of ε-upper bounded α-leakage. A Y-elementary α-leakage is proposed, extending the existing pointwise maximal leakage to the overall Rényi order range α∈ [0,∞). Maximizing this Y-elementary leakage over all attributes U of channel input X gives the Rényi divergence. Further, the Rényi capacity is interpreted as the maximal f-mean information leakage over both the adversary's malicious inference decision and the channel input X (represents the adversary's prior belief). This suggests an alternating max-max implementation of the existing generalized Blahut-Arimoto method.