Dorling Cartograms

 

http://www.ncgia.ucsb.edu/projects/Cartogram_Central/types.html

A Dorling cartogram maintains neither shape, topology not object centroids. Instead of enlarging or shrinking the objects themselves, the cartographer will replace objects with a uniform shape, usually a circle, of the appropriate size. The Demers Cartogram is used in two different ways. First, it uses squares rather than circles; this leaves fewer gaps between the shapes. Second, the Dorling Cartogram attempts to move the figures the shortest distance away from their true locations.