cabitypesNew Capital Bikeshare data sets have been added to the Activity Mapper visualization tool. I started with showing bikein & bikeout totals for each station for a single day in September; the new data sets all look at the entire 3rd quarter of 2013, from July through September. Instead of summarizing subtotals in 5-minute chunks, the new data sets have a subtotal for every day. The 3rd quarter includes the 13 CaBi stations that debuted in Montgomery County at the end of September, but since their traffic is dwarfed by the rest of the system, there is not much to see.

New controls let you customize the display. Use the + and – keys to zoom in or out (clicking will zoom and center). Ctrl+ and Ctrl- increase and decrease the size of the circle. ← and → can control the time sequence by moving backwards or forwards in time, one segment at a time.

The program compares two sets of numbers for each station. Originally, I showed the number of bikeins and bikeouts per station. (CaBi also calls these actions rentals and returns, or un-dock and dock.) A new data set compares subscribers to casual riders. Subscribers buy memberships for a month or a year, while casual riders buy the 1- or 3-day memberships. Another new data set compares “on-time” rides to “late” rides. On-time means the trip took 30 minutes or less. The rides are counted against the station where the trip ended.

piechartsFor the bikeins & bikeouts comparison, there are two data sets which look at trips that begin or end out of a specific station. I chose to create data sets for the Dupont Circle, Kennedy Center, and Georgetown University (37th & O) stations.

For now, users can not create their own data sets. The reason is that the data source is too big for a JavaScript program. The last quarter of CaBi data (a CSV file) was almost 100 megabytes. In order to create each data set, I run a small Java program which scans the giant trip-history file and creates summaries of the data I’m looking for.

There is also a new display method, “pie chart.” This is just another way of showing the same data presented in the “overlap” and “split” options. When in pie chart mode, the numbers will show the percentage being displayed, rather than the raw numbers.

The Activity Mapper is still in the early stages of its design. I’d love to get feedback on options and data sets.

See previous posts: A Day of Metro, Entries and Exits and Animating a Day of CaBi Data.

More Options for Activity Mapper

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