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} }