I made some short movies that travel back in time to show a day in the life of Washington, DC’s bike-sharing system. Using the data from Capital Bikeshare’s Trip History Data page, I looked at data for the weekend before the past two Thanksgivings. The dates are Saturday, November 20, 2010 (2,390 trips), and Saturday, November 19, 2011 (3,664 trips).

The CaBi data includes whether the rider was a casual or registered user, depending on whether the rider’s membership was for a month or longer. The movies show casual users with dots that fade from green to yellow. Registered users are represented with dots that fade from blue to purple. A histogram on the right records the number of bikes in use at each moment.

The movies exclude the trips that began and ended at the same station. (Nov 20, 2010 had 210 of these trips: 63% of them made by casual users. Casual users made up 32% of the other trips.) You will still see some dots that appear to be stationary, but they are actually moving very slowly, representing people who go far, far beyond the 30-minute time limit for free trips.

Here is the data for Saturday, November 19, 2011:

The YouTube versions were derived from the original 24-second QuickTime animations, which you can download here:

The bikes don’t have GPS transmitters on them, so all we know is the data for the start and end of each trip. Thus, all dots are shown moving in straight lines. The speed of course doesn’t correspond to the rider’s actual speed, since we don’t know their routes, or whether they paused for stops along the way.

The movie samples data at 2-minute intervals per frame, in order to compress an entire day into less than half a minute. It’s thus possible that some very short trips won’t be visible at all.

I made another version of the movie, one that samples the data every 30 seconds, but shows only noon to 6pm (in 16 seconds).

The movies were created using Processing, a Java-based tool. I used a frame of 480-by-360 pixels.

You are welcome to post the movies elsewhere, but please include a link back to this post.

Earlier, I created a bubble map showing activity for the entire quarter: Looking at CaBi Stats with a Bubble Map. Suggestions are welcome.

[This post has been updated to correct the original movie, which showed 2010 data labeled as 2011]

A Day in the Life of Capital Bikeshare

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