CheckViz

Sanity check and topological clues for linear and non-linear mappings

Sylvain Lespinats, Michael Aupetit

Research output: Contribution to journalArticle

37 Citations (Scopus)

Abstract

Multidimensional scaling is a must-have tool for visual data miners, projecting multidimensional data onto a two-dimensional plane. However, what we see is not necessarily what we think about. In many cases, end-users do not take care of scaling the projection space with respect to the multidimensional space. Anyway, when using non-linear mappings, scaling is not even possible. Yet, without scaling geometrical structures which might appear do not make more sense than considering a random map. Without scaling, we shall not make inference from the display back to the multidimensional space. No clusters, no trends, no outliers, there is nothing to infer without first quantifying the mapping quality. Several methods to qualify mappings have been devised. Here, we propose CheckViz, a new method belonging to the framework of Verity Visualization. We define a two-dimensional perceptually uniform colour coding which allows visualizing tears and false neighbourhoods, the two elementary and complementary types of geometrical mapping distortions, straight onto the map at the location where they occur. As examples shall demonstrate, this visualization method is essential to help users make sense out of the mappings and to prevent them from over interpretations. It could be applied to check other mappings as well.

Original languageEnglish
Pages (from-to)113-125
Number of pages13
JournalComputer Graphics Forum
Volume30
Issue number1
DOIs
Publication statusPublished - Mar 2011
Externally publishedYes

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Visualization
Miners
Display devices
Color

Keywords

  • evaluation
  • multidimensional data
  • multidimensional scaling
  • non-linear mapping
  • quality visualization

ASJC Scopus subject areas

  • Computer Networks and Communications

Cite this

CheckViz : Sanity check and topological clues for linear and non-linear mappings. / Lespinats, Sylvain; Aupetit, Michael.

In: Computer Graphics Forum, Vol. 30, No. 1, 03.2011, p. 113-125.

Research output: Contribution to journalArticle

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