Election time means bad information design

Hello, all, sorry that I haven't posted in a little bit. Finishing off an issue and ELECTION FEVER occupied all my mental space. I spent all of Tuesday night glued to the web, checking results, watching the electoral maps fill in with red and blue. Which reminded me of how much electoral maps tend to suck as an infographic.

Here, let me quickly show you the problem of electoral maps. Here is CNN's map for the results in the House of Representatives:

Wow, check out all that red! Looks like the Republicans won big!

Wait, what? They got trounced? Lost 29 seats and didn't gain a single one?

A congressional district represents an average of 600,000 people. In the sparsely populated states out west, that means that one district can cover an entire state, as in the case of Montana or Wyoming. In denser urban areas, a district can be much smaller, such as incoming Speaker Nancy Pelosi's district, which covers just three-quarters of a single city. Which means that a single red district can take up a hundred times the space of a dozen blue districts on an electoral map .

In addition to being bad in terms of showing data, poorly designed electoral maps are bad in terms of the modes of thinking they promote. More on that in a later post.

The New York Times was smarter with its information design. Check out their map of the House districts, which I ganked off the Skeptical Optimist:

Each equally-sized square represents one district. And the color-coding system works well too: A pale red or blue represents a district that did not change hands, while a bright red or blue is one that did. So you can clearly see at a glance that there were Democratic gains across the country, and not a single Republican one.

Maps are often used when the geographical location of the subject matter is significant, but all too often they are used in the wrong way. For instance, any map that purports to show information about the states, when that information does not have anything to do with the actual acreage of the states.

A while back some guy at some university created a map of the US in which all the states were re-sized to be of equal area, so that Rhode Island took up the same amount of space as Texas. It was brilliant, and I used it (with his permission) for an Infoporn in Wired magazine (for whom I worked at the time). I couldn't find it again with some blind googling, but if anyone out there knows what I'm talking about, could you drop me a line? Thanks!

Check back later when I'll talk about why electoral maps did as much to contribute to divisiveness in this country as any person's deliberate actions.

Disclosure: CNNMoney.com pays for Seen And Not Seen's webhosting. Although I suppose a disclosure would be more important if I were actually saying good things about CNN.

Comments

[Saheli]

I believe that maps which have bee distorted so that each individual "cell" (in this case states or voting precincts) is proportional to its weight in the map scheme are called cartograms and googling for that should find you all sorts of good stuff. From my fellow cartography groupie Snarkmarket.

[Eric Siry]

Yes, cartograms are really fascinating but I decided to leave them out of this post for further exploration later.

But one difference: I believe cartograms attempt to keep geographical relations the same despite the distortion of the individual cells... So, for instance, if four states meet at right angles, the cartogram will try to maintain those right angles between them even as each state shrinks or balloons. This results in a cartogram looking very distorted compared to a map, as states balloon out or shrink. In the example I'm trying to remember, the shapes of the states were stylized, so while geographic relationships were not necessarily maintained, and the shapes of states were reduced to straight lines and sharp angles, the overall effect is to look very recognizable as the US.

[Krzysztof]

Excellent article. Interesting subject.