Cartograms

You must have seen some of these before, especially in connection with recent US presidential elections. I picked the image above which depicts the 2008 election (Obama v/s McCain) from this University of Michigan website. Their meaning is obvious: they rescale geography, unlike normal maps, to some metric other than geographic size. In effect, one gets a better appreciation of the particular metric.

Parenthetical remark: Go Blue! I spent 7 amazing years in Ann Arbor. The guy whose website I quote above (Mark Newman of Physics) has done some work with Bob Ziff from chemical engineering on percolation theory. Bob is one of the smartest+nicest professors I have ever met. I took statistical mechanics with him, and it was one of the two career-defining classes I took at UM (the other was my advisor Ron Larson's class, Complex Fluids). End of parenthetical remark.

Another wonderful resource for cartograms which is less US-centric and more global in scope is this site. If you look at the population of the world from year 0001 through now, you realize why the Indian sub-continent and China have the largest populations.

This is interesting to me, because about 6 months ago over a cup of coffee, my colleague Milen Kostov and I were trying to figure out why India and China have large populations, and not, say Egypt or Mesopotamia (modern day Iraq) which were also cradles of ancient civilizations. Looks like something happened between 0001 and 1500 AD, where you can see that their sizes sort of diminished or remained same relative to India-China. Perhaps being in a desert limited how much food could be grown to support a population.