The “On…” series is a collection of short blog posts relating to data visualization, economics, presentation skills, or data communication. In each, I discuss an issue, concept, or idea that I have not fully developed, a work in progress, or just some thoughts about a topic or issue I’d like to share.
This tweet got a lot of attention over the weekend and it seemingly got some people fired up. Personally, having lived in both New York City and DC, it’s interesting how my perception of these cities correspond to the subway maps and not the actual orientation of the cities.
Not to ruin your day but Union Square is further west than the Port Authority Bus Terminal, the Empire State Building is directly south of Times Square, most of the East Village is further west than Columbus Circle and the whole Williamsburg Bridge is west of the UN HQ. pic.twitter.com/EHi7z0nJ9k
— Gus (@goldisacks) May 24, 2020
The NYC subway map, for example, rotates the entire city counter-clockwise a few degrees. It makes the map easier to read, but probably enters our subconscious that this is how the city is actually aligned. That’s why the original tweet struck a chord with me (and, apparently, many others).
The DC metro map, by contrast, keeps the North-South orientation as it truly is–easier, perhaps, because the city is divided into four quadrants (NW, NE, SW, SE)–and thus, by comparison, our/my perception of the city and the North-South orientation are aligned.
Maps are a tricky thing when it comes to data visualization. Readers love them because they are able to identify themselves in the data and visualization, but they do not always accurately represent the data. In this case, I found it interesting how our perception of space is likely shaped by the maps we use each and every day.
New York isn’t aligned to the subway map: it’s aligned to the street grid in Manhattan that precedes the subway by some considerable length of time. The subway map simply adheres to the already-established local convention that “north” is uptown and “south” is downtown, traveling along the long, straight avenues of Manhattan.
See also: Montreal, where local north most definitely isn’t geographical north.