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Medial-Axis-Based Cartograms
May/June 2005 (vol. 25 no. 3)
pp. 60-68
Daniel A. Keim, University of Constance, Germany
Christian Panse, University of Constance, Germany
Stephen C. North, AT&T Shannon Laboratory
Cartograms are a well-known technique for showing geography-related statistical information, such as demographic and epidemiological data. The idea is to distort a map by resizing its regions according to a statistical parameter, but in a way that keeps the map recognizable. This article describes a method of continuous cartogram generation, which strictly retains the input map's topology. It presents an algorithm that makes cartograms by iterative relocation of the map's vertices, guided by a modified medial axes transformation. Application experiments show that the proposed algorithm can make high-quality cartograms in interactive time, even for large maps. Additional examples help to demonstrate its potential.

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Index Terms:
cartogram, contiguous cartograms, mesh transformation, drawing algorithm, information visualization, geovisualization, medial axes transformation, cartodraw
Daniel A. Keim, Christian Panse, Stephen C. North, "Medial-Axis-Based Cartograms," IEEE Computer Graphics and Applications, vol. 25, no. 3, pp. 60-68, May-June 2005, doi:10.1109/MCG.2005.64
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