2007/10/05 by Hua Li, Edwin K. P. Chong, Li, Hua +1
Computer Science · Mathematics · Physics and Astronomy · #Computability, Logic, AI Algorithms #FOS: Computer and information sciences #Information Theory (cs.IT) #Neural Networks and Applications #Statistical Mechanics and Entropy #cs.IT #math.IT
paper · pdf · doi:10.48550/arxiv.0710.1254
Submitted to IEEE Transactions on Information Theory
arxiv created 2007/10/05 · openalex publication_date 2007/10/05 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
In this paper we formalize the notions of information elements and information lattices, first proposed by Shannon. Exploiting this formalization, we identify a comprehensive parallelism between information lattices and subgroup lattices. Qualitatively, we demonstrate isomorphisms between information lattices and subgroup lattices. Quantitatively, we establish a decisive approximation relation between the entropy structures of information lattices and the log-index structures of the corresponding subgroup lattices. This approximation extends the approximation for joint entropies carried out previously by Chan and Yeung. As a consequence of our approximation result, we show that any continuous law holds in general for the entropies of information elements if and only if the same law holds in general for the log-indices of subgroups. As an application, by constructing subgroup counterexamples we find surprisingly that common information, unlike joint information, obeys neither the submodularity nor the supermodularity law. We emphasize that the notion of information elements is conceptually significant--formalizing it helps to reveal the deep connection between information theory and group theory. The parallelism established in this paper admits an appealing group-action explanation and provides useful insights into the intrinsic structure among information elements from a group-theoretic perspective.