Visualization of Varying Hierarchies by Stable Layout of Voronoi Treemaps

Sebastian Hahn, Jonas Trümper, Dominik Moritz, Jürgen Döllner

Abstract

Space-restricted techniques for visualizing hierarchies generally achieve high scalability and readability (e.g., tree maps, bundle views, sunburst). However, the visualization layout directly depends on the hierarchy, that is, small changes to the hierarchy can cause wide-ranging changes to the layout. For this reason, it is difficult to use these techniques to compare similar variants of a hierarchy because users are confronted with layouts that do not expose the expected similarity. Voronoi treemaps appear to be promising candidates to overcome this limitation. However, existing Voronoi treemap algorithms do not provide deterministic layouts or assume a fixed hierarchy. In this paper we present an extended layout algorithm for Voronoi treemaps that provides a high degree of layout similiarity for varying hierarchies, such as software-system hierarchies. The implementation uses a deterministic initial-distribution approach that reduces the variation in node positioning even if changes in the underlying hierarchy data occur. Compared to existing layout algorithms, our algorithm achieves lower error rates with respect to node areas in the case of weighted Voronoi diagrams, which we show in a comparative study.

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Paper Citation


in Harvard Style

Hahn S., Trümper J., Moritz D. and Döllner J. (2014). Visualization of Varying Hierarchies by Stable Layout of Voronoi Treemaps . In Proceedings of the 5th International Conference on Information Visualization Theory and Applications - Volume 1: IVAPP, (VISIGRAPP 2014) ISBN 978-989-758-005-5, pages 50-58. DOI: 10.5220/0004686200500058


in Bibtex Style

@conference{ivapp14,
author={Sebastian Hahn and Jonas Trümper and Dominik Moritz and Jürgen Döllner},
title={Visualization of Varying Hierarchies by Stable Layout of Voronoi Treemaps},
booktitle={Proceedings of the 5th International Conference on Information Visualization Theory and Applications - Volume 1: IVAPP, (VISIGRAPP 2014)},
year={2014},
pages={50-58},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0004686200500058},
isbn={978-989-758-005-5},
}


in EndNote Style

TY - CONF
JO - Proceedings of the 5th International Conference on Information Visualization Theory and Applications - Volume 1: IVAPP, (VISIGRAPP 2014)
TI - Visualization of Varying Hierarchies by Stable Layout of Voronoi Treemaps
SN - 978-989-758-005-5
AU - Hahn S.
AU - Trümper J.
AU - Moritz D.
AU - Döllner J.
PY - 2014
SP - 50
EP - 58
DO - 10.5220/0004686200500058