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ArticleOriginal scientific text

Title

Modular and median signpost systems and their underlying graphs

Authors 1, 2

Affiliations

  1. Econometrisch Instituut, Erasmus Universiteit, P.O. Box 1738, 3000 DR Rotterdam, The Netherlands
  2. Filozofická fakulta, Univerzita Karlova v Praze, nám. J. Palacha 2, 116 38 Praha 1, Czech Republic

Abstract

The concept of a signpost system on a set is introduced. It is a ternary relation on the set satisfying three fairly natural axioms. Its underlying graph is introduced. When the underlying graph is disconnected some unexpected things may happen. The main focus are signpost systems satisfying some extra axioms. Their underlying graphs have lots of structure: the components are modular graphs or median graphs. Yet another axiom guarantees that the underlying graph is also connected. The main results of this paper concern if-and-only-if characterizations involving signpost systems satisfying additional axioms on the one hand and modular, respectively median graphs on the other hand.

Keywords

ENG
signpost system, modular graph, median graph

Bibliography

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Discussiones Mathematicae Graph Theory
2003/23/2
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Pages:
309-324
Main language of publication
English
Received
2001-10-01
Accepted
2002-04-05
Published
2003

DOI: 10.7151/dmgt.1204

Exact and natural sciences