A Short Optimal Way for Constructing Quasi-ultrametrics From Some Particular Dissimilarities

  • B. Fichet
Conference paper
Part of the Studies in Classification, Data Analysis, and Knowledge Organization book series (STUDIES CLASS)


Recently, Diatta has established a lower maximal quasi-ultrametric approximation of a dissimilarity fulfilling the inclusion condition. The approach is purely algorithmical, but incidentally the solution is characterised by a formula. From this formula, we give here two straightforward and short proofs of the result. One is based on the properties of the dissimilarities under consideration, and the second one derives from the bijection between quasi-ultrametrics and indexed quasi-hierarchies.


Discrete Math Level Index Cluster Partition Inclusion Condition Dissimilarity Function 
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Copyright information

© Springer-Verlag Berlin · Heidelberg 2000

Authors and Affiliations

  • B. Fichet
    • 1
  1. 1.Laboratoire de BiomathématiquesAix-Marseille II UniversityMarseille, Cedex 5France

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