How Powerful/Aerially-Connected is Your City?
Explore My First “Real” D3 Visualization to Find Out
First, A Quick Plug for D3.js
I’ve been learning d3.js and I’m blown away by it. A while back I tried building an interactive visualization using R’s Shiny. I found it powerful, but was a bit stymied by the server-side setup — not exactly easy to deploy on just any old server.
D3.js has a confusing update cycle (at least to me), but that’s the only thing I don’t like about it. It’s amazing how extensively you can customize its output. If you can imagine it, you can make it. And there will always be a bl.ock sample to get you started down the right path.
If you’re interested in learning d3.js, I’d recommend this short Udemy course. The instructor knows his stuff, and he’s built some real-world starter projects to take you from the simple to complex in a matter of weeks.
After finishing it, I wanted to try to make something around my interest in aviation data. I crunched the latest dump of OpenFlights.org data in R (still love it for data prep) and spit out routes for the 100 most connected cities.
Aerially-Connected Cities are Powerful Cities
The first thing that’s interesting about the data is how much a city’s degree of aerial-connectedness overlaps with various indices of city power. Globalization and World Cities Research Network (GaWC) and other organizations compile annual lists of city power rankings based on metropolitan GDP estimates and other data.
Their selection criteria sound complicated, and some are proprietary. But you get something decently close to the GaWC top 100 just by ranking cities by the number of outbound flights they offer.
That’s what this venn diagram shows.
The two lists have 65 overlapping items. If you want to live in a powerful city, you could do worse than simply measuring the thickness of its outbound flight schedule.
For the ultra-curious, check out this bipartite graph showing the rank correspondence between the top-50 cities in each list.
Notice that certain airline hub cities (Atlanta and Dallas, for example) rank much higher in aerial connectedness than power. Their connectedness, it would seem, is due more to the hub-and-spoke routing practices of major airlines than their overall economic power.
So How Aerially-Connected is Your City?
Does it even make the list? (I’m living in #18!)
Explore my viz to find out. Run though the whole list of 100 via the dropdown menu. Hover over the sankey bars (yes, those are things) on either side to see the routes plotted (that part took a while!).
You’ll notice that the top 20 or so cities are truly globally connected, offering many regional and direct trans-continental flights. As you descend deeper into the list, the number of direct trans-continental flights on offer diminishes leaving mostly just regional flights.
