an algoritm to construct continuous area cartograms,
by James A. Dougenik, Nicholas R. Chrisman and Duane R. Niemeyer,
©1985 by the Association of American Geographers.
Cartogram.js is designed and built by Shawn Allen at
Stamen and has a home on Github. It runs with
d3.js by Mike Bostock.
This Georgia example runs with d3.v2, an older version.
It's based on a tutorial from Jeff Fletcher on his South Africa dataviz blog Limn. He bundles up the appropriate versions of cartogram, topojson and d3 here.
Data source: Population as of July, 2014 from the U.S. Census, downloaded June 26, 2015.
Population icon by Wilson Joseph from the Noun Project.