City Research Online

Spatially Ordered Treemaps

Wood, J. and Dykes, J. (2008). Spatially Ordered Treemaps. IEEE Transactions on Visualization and Computer Graphics, 14(6), pp. 1348-1355. doi: 10.1109/TVCG.2008.165

Abstract

Existing treemap layout algorithms suffer to some extent from poor or inconsistent mappings between data order and visual ordering in their representation, reducing their cognitive plausibility. While attempts have been made to quantify this mismatch, and algorithms proposed to minimize inconsistency, solutions provided tend to concentrate on one-dimensional ordering. We propose extensions to the existing squarified layout algorithm that exploit the two-dimensional arrangement of treemap nodes more effectively. Our proposed spatial squarified layout algorithm provides a more consistent arrangement of nodes while maintaining low aspect ratios. It is suitable for the arrangement of data with a geographic component and can be used to create tessellated cartograms for geovisualization. Locational consistency is measured and visualized and a number of layout algorithms are compared. CIELab color space and displacement vector overlays are used to assess and emphasize the spatial layout of treemap nodes. A case study involving locations of tagged photographs in the Flickr database is described.

Publication Type: Article
Publisher Keywords: Geovisualization, treemaps, cartograms, CIELab, geographic information, tree structures, SPACE, MAPS
Subjects: Z Bibliography. Library Science. Information Resources > Z665 Library Science. Information Science
Departments: School of Mathematics, Computer Science & Engineering > Library & Information Science
School of Mathematics, Computer Science & Engineering > Computer Science > giCentre
URI: http://openaccess.city.ac.uk/id/eprint/536
[img]
Preview
PDF
Download (21MB) | Preview

Export

Downloads

Downloads per month over past year

View more statistics

Actions (login required)

Admin Login Admin Login