Saturday, November 12, 2016

NYC, Population and Density

Take a quick look at this viz:


What the heck is up with Manhattan? Too much time at the Shake Shack? And why does Staten Island look like a deflated balloon? The above map is what is known as a cartogram. A cartogram takes a feature within a geography and resizes it by that feature. In this picture we see the 5 Burroughs of New York, divided into their separate neighborhoods, and sized by population. New York City's normal geographic boundaries have their area resized to match their relative populations. I have also colored the neighborhoods to further show the largest neighborhoods by population.
By contrast, we can see how the geography has been distorted when we overlay the actual boundaries.
This type of cartogram can come off as too literal however; the distortions sometimes do not offer enough information for the mind to really better understand area. In a broad sense, we get that Manhattan is full of people and Staten Island has very few people. But how many fewer?
The eye is terrible at reading absolute area and making decisions from it. So a simple bar chart, while somewhat dry, is the easiest way to understand how New York City is divided.
We can see that Brooklyn easily bests Queens and Manhattan for population, while Staten island has roughly the same population as the Reno-Tahoe area. But even that diminishes Manhattan. Manhattan's density is on par with some of the densest cities in the world. The large populations of Brooklyn and Queens are still pretty spread out.
Instead, let's look at each Burrough's density:
The labels show the percent of total density relative to Manhattan while the bars show, in thousands, the number of people per square mile. In other words, Staten Island is less than 1/10th as dense as Manhattan. The large total area of Queens means that while it is the second largest of the five Burroughs, its citizens can stretch their legs out comfortably without fear of bumping into another human.
Ultimately, we would be best off giving people a chance to actually explore the data a bit. What are the populations of neighborhoods in New York City by neighborhood? How about if we sort it by Burrough? Take a look below and see how New York's neighborhoods stack up.