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On the stack-size of general tries

Jérémie Bourdon, Markus Nebel, Brigitte Vallée (2001)

RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications

Digital trees or tries are a general purpose flexible data structure that implements dictionaries built on words. The present paper is focussed on the average-case analysis of an important parameter of this tree-structure, i.e., the stack-size. The stack-size of a tree is the memory needed by a storage-optimal preorder traversal. The analysis is carried out under a general model in which words are produced by a source (in the information-theoretic sense) that emits symbols. Under some natural assumptions...

On the Stack-Size of General Tries

Jérémie Bourdon, Markus Nebel, Brigitte Vallée (2010)

RAIRO - Theoretical Informatics and Applications

Digital trees or tries are a general purpose flexible data structure that implements dictionaries built on words. The present paper is focussed on the average-case analysis of an important parameter of this tree-structure, i.e., the stack-size. The stack-size of a tree is the memory needed by a storage-optimal preorder traversal. The analysis is carried out under a general model in which words are produced by a source (in the information-theoretic sense) that emits symbols. Under some natural...

One-adhesive polymatroids

Laszlo Csirmaz (2020)

Kybernetika

Adhesive polymatroids were defined by F. Matúš motivated by entropy functions. Two polymatroids are adhesive if they can be glued together along their joint part in a modular way; and are one-adhesive, if one of them has a single point outside their intersection. It is shown that two polymatroids are one-adhesive if and only if two closely related polymatroids have joint extension. Using this result, adhesive polymatroid pairs on a five-element set are characterized.

Optimally approximating exponential families

Johannes Rauh (2013)

Kybernetika

This article studies exponential families on finite sets such that the information divergence D ( P ) of an arbitrary probability distribution from is bounded by some constant D > 0 . A particular class of low-dimensional exponential families that have low values of D can be obtained from partitions of the state space. The main results concern optimality properties of these partition exponential families. The case where D = log ( 2 ) is studied in detail. This case is special, because if D < log ( 2 ) , then contains all probability...

Order statistics and ( r , s ) -entropy measures

María Dolores Esteban, Domingo Morales, Leandro Pardo, María Luisa Menéndez (1994)

Applications of Mathematics

K. M. Wong and S. Chen [9] analyzed the Shannon entropy of a sequence of random variables under order restrictions. Using ( r , s ) -entropies, I. J. Taneja [8], these results are generalized. Upper and lower bounds to the entropy reduction when the sequence is ordered and conditions under which they are achieved are derived. Theorems are presented showing the difference between the average entropy of the individual order statistics and the entropy of a member of the original independent identically distributed...

Properties of unique information

Johannes Rauh, Maik Schünemann, Jürgen Jost (2021)

Kybernetika

We study the unique information function U I ( T : X Y ) defined by Bertschinger et al. within the framework of information decompositions. In particular, we study uniqueness and support of the solutions to the convex optimization problem underlying the definition of U I . We identify sufficient conditions for non-uniqueness of solutions with full support in terms of conditional independence constraints and in terms of the cardinalities of T , X and Y . Our results are based on a reformulation of the first order conditions...

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