Andy Woodruff, Robert Roth, and Zachary Johnson have a new paper in the latest issue of The Cartography Journal of the British Cartographic Society called “Value-by-alpha Maps: An Alternative Technique to the Cartogram”.
Value-by-alpha maps (hereafter shortened to VBA), like everything noble and good, have their roots in somebody complaining about something on the internet—me, about election cartograms. Seeking an alternative to what I think are ugly and unreadable election results cartograms, I worked with my Axis Maps dudes to create a 2008 U.S. election map that used transparency rather than size to vary the visual impact of map units, thinking that avoiding the distortion of these units into unrecognizable sizes and shapes would make the map easier to read.
One of the more interesting contributions in the paper is their solution to “Johnson’s Cube” where they map the 3 axes to Visual Equalisation, Topology Preservation, and Shape Preservation and show cartographic rendering techniques to illustrate the various combinations.
