Published in Volume XXV, Issue 1, 2015, pages 155-170, doi: 10.7561/SACS.2015.1.155

Authors: D. A. Simovici

Abstract

We investigate the relationships between tolerance relations, equivalence relations, and ultrametrics. The set of spheres associated to an ultrametric space has a tree structure that rejects a hierarchy on the set of equivalences associated to that space. We show that every ultrametric defined on a finite space is a linear combination of binary ultrametric and we introduce the notion of ultrametricity for dissimilarities, which has applications in many data mining problems.

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Bibtex

@article{sacscuza:simovici2015srodau,
  title={Several Remarks on Dissimilarities and Ultrametrics},
  author={D. A. Simovici},
  journal={Scientific Annals of Computer Science},
  volume={25},
  number={1},
  organization={``A.I. Cuza'' University, Iasi, Romania},
  year={2015},
  pages={155--170},
  doi={10.7561/SACS.2015.1.155},
  publisher={``A.I. Cuza'' University Press}
}