Seven Months of Nice Rides
February 2nd, 2013 [programming]
Let’s look at trip history data for the bike-sharing system in Minneapolis and St Paul. I’ve adapted the CaBi Trip Visualizer for Nice Ride Minnesota. They’ve released a seven-month chunk of data, covering April 4, 2012 to November 4, 2012. It was easy to adapt the program for their data. So, voilà: the Nice Ride Trip Visualizer.
Click on any station to see the stations that form the most station-pairs. Not being familiar with the Twin Cites, I wanted to see the entire system’s network. To do that, hit the “1″ key to select all the stations visible on the map. I was surprised to see the most prominent station-pair spans the Mississippi River, from Kolthoff Hall to the Social Sciences building, both on the campus of the University of Minnesota. These trips must use the Washington Avenue Bridge.
As it turns out, the Kolthoff-Social Sciences trips aren’t the most common. The most common trip doesn’t show up on the map because it begins and ends at the same station, Lake Calhoun Center. I used to assume loop trips were just joy rides taken by people unfamiliar with the system, but there must be a reason why this station has so many loop trips. Any ideas?
The table below shows the 10 most-popular trips for this seven-month period:
| trips | start | end |
|---|---|---|
| 4231 | Lake Calhoun Center | Lake Calhoun Center |
| 2164 | Kolthoff Hall | Social Sciences |
| 2054 | Social Sciences | Kolthoff Hall |
| 1175 | Lake Street & Humboldt | Lake Street & Humboldt |
| 1113 | 100 Main Street SE | 100 Main Street SE |
| 790 | Lake Street & Humboldt | Lake Calhoun Center |
| 739 | Lake Calhoun Center | Lake Street & Humboldt |
| 716 | South 2nd Street & 3rd Ave. S | IDS Center |
| 699 | 4th Street & 13th Ave. SE | Kolthoff Hall |
| 668 | IDS Center | South 2nd Street & 3rd Ave. S |
I’ve built in three clusters to look at subsets of the region. They’re listed below the station names in the drop-down menu, or use the short-cut keys: M for Minneapolis, S for St Paul, and U for the University of Minnesota campus in Minneapolis.
Of the 273,999 recorded trips, 38% were taken by casual riders (using a 24-hour membership). 62% were taken by subscribers (those with 30-day or annual membership). But for loop trips, the percentage of casual riders goes up to 71%, which bolsters my suspicion that loop trips are made primarily by those less-familiar with the system.
The Nice Ride system had an average of 1,263 daily trips, with a high of 2,848 trips taken on Saturday, June 9, 2012. The video below shows a 24-hour period, from a lull at 4 in the morning to 4am Sunday morning.
The animation makes it clear that only 9% of trips begin in St Paul, though 33% of the stations are in St Paul (on the right). The Minneapolis portion clearly dominates. And though there weren’t many people riding bikes early Saturday morning, the system got heavy use long past midnight. (Last call in Minneapolis is at 2am.)
The colors represent the type of user and the percent of the trip that has been completed. Casual riders are shown with circles that change from green to yellow, and subscribers are shown with circles that change from blue to purple.
You can view the movie in its original QuickTime format by downloading the niceride.mov file (17MB).
These sorts of analyses can be done only with systems that have open data. Though many bikesharing systems provide station information, it is rare to find any that share trip history data. So far I’ve found data for these three regions:
- CaBi Trip Visualizer (Washington, DC; Arlington, VA; Alexandria, VA)
- Hubway Trip Visualizer (Boston)
- Nice Ride Trip Visualizer (Minneapolis and St Paul)
For a closer look at the bikesharing system in Washington, DC, see Capital Bikeshare’s 4th Quarter of 2012 and Bikeshare Stats on a Map.
It’s just a guess, but the bike trail that goes around Lake Calhoun and connects to the rest of the Chain of Lakes (Lake Harriet, Lake of the Isles) is the reason for that large number. They are indeed joy rides. Does the data say how many of those trips have extra time charges?
12% of all rides throughout the system are over 30 minutes. For “loop trips,” that percentage goes up to 55%. And for loop trips to and from Lake Calhoun, 72% of trips go over 30 minutes! In fact, the average Lake Calhoun loop trip is over 56 minutes long.
Yep, that seems teo confirm my theory that the majority of rides from that location literally are loop trips; they loop around Lake Calhoun, one of the most popular places in the Twin Cities to bicycle.