David Montgomery at the Pioneer Press has a great piece up today demonstrating the difference between a “regular” map projection and a cartogram when it comes to representing population and political balance.
Here are his two maps of the state’s legislative senate districts, along with one that I added showing the core city senate districts:
Here’s what Montgomery says about the difference:
My selection of “metro” districts was of course, somewhat arbitrary. You could easily expand the yellow to include more suburban areas, or subtract suburban areas to reduce it to the urban core. Both of those tell different stories of political geography, and I hope to revisit them over the coming months.
Check out the whole story. The good news is that he’s promising more spatial analysis!
I’d like to see a similar geographic display of GDP, tax receipts, or other economic indicators. My guess is that the core cities and the metro as a whole would have significantly larger shares. Though it’s much harder to do such an analysis since, unlike senate districts and population, I cannot think of boundaries which contain roughly equal units of economic activity.
Well, GDP:
2013 MN $312bn https://research.stlouisfed.org/fred2/series/MNNGSP
2013 MSP Metro: $227.8bn http://bea.gov/newsreleases/regional/gdp_metro/2014/pdf/gdp_metro0914.pdf
MSP Share of state: 73%
And what’s the MSP metro’s share of tax expenditure? I’m guessing it’s not even close to 73%.
IIRC, the state publishes tax receipt data by county. So it might be possible to do a cartogram of tax receipts by county if one has the right software…
One standalone, relatively user-friendly tool–if you have a shapefile–is scapetoad (http://scapetoad.choros.ch).
If you’ve got a bit of programming, you can try protovis (http://mbostock.github.io/protovis/ex/cartogram.html) or d3 (http://bl.ocks.org/mbostock/4055908)
I’m sure there are others. I didn’t see Montgomery mention what he used.
Literally spectacular!