Sometimes all you need is data.
I went back to New York a couple weeks ago, and staying in DUMBO while trying to pretend I lived in Williamsburg again put the subway back on my mind [and brought back memories of my commute to DUMBO, taking the J in to Essex then the F back out to York].
Then a couple days after I got back, I saw Mike Frumin’s post Spark It Up. It’s pretty gorgeous, and tells a lot of little fascinating stories, but what really tickled me was the fat spreadsheet of MTA ridership data Frumin used to create the map.
My first thought was to do something like my mapping of spending in the city — that sea of sparklines just demanded a z-axis. But I wanted to be able to scrub back and forth in time, so I started working on a ModestMaps-powered map with a time slider. After getting the data into the right shape, it was pretty quick to get something simple but interactive and visual up.
Some of the immediate things I realized, scrubbing back and forth in time, was just how high ridership used to be in the 1940s and 1950s, though significant changes like the token to Metrocard / Unlimited Metrocard seem to be affecting ridership. Here’s an atrophied 1977 vs 2006:
I can’t say much more about the data than Frumin’s original post, but it is pretty great to watch Midtown act as the throbbing heart of Manhattan, and the various lines spidering out into the Bronx.
After getting great feedback from my awesome coworkers at Stamen, I added some context to the time slider and some tooltips that feel about right to my eyes [writing the MTABadge class was especially fun]. Also, I set up a relative scaling mode, where all stations are scaled relative to their respective maximums. This gives you the Williamsburg boom that’s otherwise dwarfed by the volume of Midtown traffic.
The current piece is up now, here.
very sexy, but dangerous. As per my IM chat with Migurski:
(5:13:57 PM) altmigurski@mac.com: http://diametunim.com/blog/2009/05/historical-nyc-ridership/
(5:14:38 PM) fruminator: this is dangerous
(5:14:46 PM) altmigurski@mac.com: =)
(5:14:57 PM) fruminator: link widths are usually taken to imply the # of passengers on a given section of railway/bus network
(5:15:17 PM) fruminator: but that is totally ont the case here
(5:15:24 PM) fruminator: I would just make them scaled dots
(5:15:29 PM) altmigurski@mac.com: yeah, whereas your data is just stations
(5:16:41 PM) fruminator: but the badge/slider is awesome
(5:17:00 PM) fruminator: what does he do about stations with many lines?
(5:17:17 PM) altmigurski@mac.com: I think that basically he’s just scaling the station dt,
(5:17:18 PM) altmigurski@mac.com: *dot
(5:17:35 PM) altmigurski@mac.com: and interpolating the segment widths from it to every connected neighbor in the graph
(5:17:36 PM) fruminator: no, i mean he has the slider with volumes on each line (on the bottom left)
(5:17:43 PM) altmigurski@mac.com: oh I see
(5:17:50 PM) altmigurski@mac.com: that’s a good question
(5:18:08 PM) altmigurski@mac.com: maybe ask in the comments? he’s thinking about it a bunch now
fruminator
18 May 09 at 1:22 pm
yes, definitely only having data on stations forces the histogram to act just as context [the histogram should really just be one color] — there are no numbers.
i was thinking about actually splitting up the drawn lines when there are multiple lines, but there’s no data for it. the motive, though, was to specifically *not* just place dots on the map. even if all the lines were the same color, it still gives us more information about the flow through the system.
[specifically, i thought there was a problem with the data when the 1 line breaks around Cortland St, but then i realized that that was probably shut down after 9/11.]
sha
18 May 09 at 2:04 pm
I completely disagree. You know nothing about the flow from simply the station boardings. All you can do with any level of certainty here is place dots. Anything else you are just making up numbers out of thin air.
fruminator
19 May 09 at 5:58 am
Regardless of whether the line thickness truly represents the flow, this is just awesome!
cassidy
19 May 09 at 6:24 am
This is awesome! (silent long awe)… Having never been to NY though, I can appreciate the effort and time behind the project. Well done!
hoopyfrood
6 Sep 09 at 7:20 pm
This is awesome; thank you for sharing.
Recently, I wondered how to make a map of household income by zip code over time in NYC? What do you think?
Adrian Palacios
2 Oct 09 at 8:06 am
This reminds of of http://www.informationisbeautiful.net
Great work!
Brendan L
12 Mar 10 at 11:12 pm