The Future of OneBusAway

I wanted to update all of you OneBusAway users on the status of the system.

OneBusAway started out as a student project at the University of Washington, and progressed to become the primary topic of the PhD dissertations for Brian Ferris (Computer Science & Engineering) and Kari Watkins (Civil & Environmental Engineering).  Both Brian and Kari graduated in summer 2011; Brian headed to work for Google in Zurich, and Kari to become an assistant professor at Georgia Tech.  Since OneBusAway had become so widely used, three area agencies (King County Metro, Sound Transit, and Pierce Transit) contracted with the University of Washington to continue running OneBusAway for a year, and then again for another six months.  There are now over 100,000 users per week of the system in Puget Sound.  The contract is expiring in mid-May, and sometime around then Sound Transit will be taking over running it.  (Sound Transit already has an experimental version of OneBusAway running in parallel with the production system.)

We hope that the transition will be relatively seamless.  OneBusAway will continue to provide real-time arrival information for Metro, Sound Transit, Pierce Transit, and Intercity Transit, with schedule-only information for several others — and hopefully more in the future. Existing apps should continue to function without change.

At the same time, instances of OneBusAway have been brought up in other regions, including Atlanta, Detroit, and Tampa; the OneBusAway Enterprise system (derived from the core OneBusAway) is the basis for the BusTime system in the greater New York region.  To help support this, we are making versions of the OneBusAway apps that will work in multiple regions.  We university types will also continue doing research on providing better and additional types of transit information (such as alerts, real-time replanning, vehicle capacity information, and others), integrating incentives for transit use with OneBusAway, crowd sourcing the detection and resolution of data problems with real-time transit data, and providing tools that seek to benefit all riders, including blind and low-vision, mobility impaired, and others.

I wanted to end with thanks to a few of the many people who have helped with OneBusAway.  In alphabetical order: to Joel Bradbury and Dan Dailey, for pioneering real-time transit information in Puget Sound and continuing to provide data to OneBusAway for much of the project's lifetime; to Brian Ferris, for continuing to provide essential help even after moving to Zurich; to S. Morris Rose, software engineer in Computer Science & Engineering, for being the mainstay of our efforts to keep OneBusAway up; and finally to King County Metro, Pierce Transit, and Sound Transit for being willing to invest in keeping the system going and helping transition it to a long-term home.

sincerely, Alan Borning Professor, Department of Computer Science & Engineering

Announcing the OneBusAway Ambassadors Program

Hi there, OBA power users. Do you want to get in on the action?

We all recognize that there have been data errors in Seattle-area real-time bus arrival information stemming from a variety of sources. We also all know that King County Metro is working hard to fix it, but they are limited to their own diagnostic data.  It’s the user on the street and on the bus who knows exactly when they get a prediction error and it’s that user that we’re giving a chance to help fix it.  Hopefully you’ve all seen the error reporting feature in the iPhone app.  (A similar feature is being developed for Android as well.)  To build off of this feature and use those error reports better, we have a new program starting up called the OneBusAway Ambassadors.  OneBusAway has always been a community-generated and supported tool.  We were started by UW students with help from some great UW faculty.  We are trying to maintain that community support.  So if you are a OneBusAway fan and are interested in beta testing-type endeavors, now is your change to jump in.  We’re currently recruiting volunteers to serve as OneBusAway Ambassadors.

The Ambassador program will initially involve a set of OBA Ambassadors viewing and validating the incoming error reports created via the iPhone error reporting function as well as validating emails to OBA regarding prediction errors.  The OBA Ambassadors will act as liaisons in which to aggregate and identify trends in errors based on the actual bus or the route that is being reported. This information will get passed back to the relevant agency or the OBA staff in order to assist them in error identification and resolution.  We are currently planning on each Ambassador  devoting about 2-3 hours per week.   The rewards will be endless in the form of kudos from the public, knowing that you are making transit easier to use, and really cool OneBusAway Ambassador apparel that will make you the envy of your transit buddies.

If you are interested in being a OneBusAway Ambassador, email Kari Watkins at kariwat@uw.edu.

Thanks for your support of OneBusAway!

Please Take the New OneBusAway User Survey

After three years and many changes, the UW team that runs OneBusAway is looking for feedback about the service. Have you used OneBusAway within the past three years? If so, please help us understand how you use it by taking a quick survey, located here: (https://catalyst.uw.edu/webq/survey/kariwat/168983). The survey is anonymous and those who take the survey are eligible to win a $25 iTunes gift card. Thanks again for your input.

On the Metro Transition to GPS

A user asks:

When will OneBusAway be based on GPS tracking of each Metro bus, so that it will be more accurate and work (at least for locating buses) even when buses have to be re-routed?

Would that it were that simple. We are told that the transition to GPS, already well over half complete, will be over by early Autumn, but it may deliver less than you thought it promised.

Here's the basic idea of how OneBusAway works. There are two parts:

1. About four times a year, OBA gets a schedule from each of the agencies, including Metro. The schedule says "here's where and when all the buses are going to stop from now until the end of the service interval several months from now." For example, it might say- for one of the almost 30,000 KCM trips the schedule describes- that there's going to be a route 16 trip every weekday starting at 7:18 AM- and here's where and when it's going to stop- and this is the ID it will be labeled with.

2. Every day, all day, we get real-time reports of trips- tens of thousands of them. What we get in each report isn't so much "here's where the bus is" but rather "here's how this trip is performing against the scheduled trip." Something like "trip X is running Y seconds off schedule."  Ahead of, behind, or spot on. That's called "schedule deviation."

So- we know where the agency said it would be, and we know what the "schedule deviation" is. We might also know where the bus is, but it's all but irrelevant.

A user is standing on the street at a stop, and she asks OBA: tell me about any trips that are headed to this stop. OBA looks at the schedule and looks at the real-time reports and computes: here are the trips that are supposed to be there soonish, and here's what we know about how those trips are performing. Add it all up, and it's able to give you the display you seen on a smart phone: this trip looks to be five minutes late, we've seen no recent realtime data for this other trip but it's scheduled to be here in eight minutes so we'll show you that, and here are five other trips with this or that status.

How does GPS make any of this better from the old bus-location system? Only this way: the old system delivered less frequent reports of less accurate location data. Therefore, real-time reporting could compute less accurate schedule deviation.

GPS is not a silver bullet. It does make some new stuff possible, such as detecting when a bus is off route, but there is a bunch of design and engineering between where we are and presenting that to a rider in a useful way.  In particular, we are some ways from being able to present the rider with the actual location of a bus that is off-route.

A Metapost

Wayne Watanabe of the King County Department of Transportation and OneBusAway's Mark Hallenbeck have collaborated on Tracking the Bus Tracker Problems, a post at the Seattle Transit Blog that looks at recent problems with real-time bus location reporting for King Country Metro (and digitizing grandpa's classic rock collection). It's a good and geeky read if you skew that way. The commenters are great at cutting us a new one, too.

On OneBusAway Inaccuracies

(This post is by S. Morris Rose. I'm the engineer that's been hired on a temporary basis to keep the services that power OneBusAway chugging away now that Brian Ferris, the engineer that created it, has moved on to work on transit projects at Google Zurich, though he still pitches in from time to time. The position is funded by contracts with King County Metro, Pierce Transit, and Sound Transit. I've been a technical staff member for Computer Science & Engineering at the University of Washington, where OneBusAway was created, for more than a decade.)

Many users have noticed that sometimes OneBusAway isn't real accurate- it might report a bus is early when it's on time, late when it's early, or display the status labeled, "scheduled departure" (which means that there is no "real time" arrival data available for that trip), or a scheduled trip might simply be missing. In the case of Community Transit (which is not a project funder), the schedule data has simply gone missing. In this post, I'll explain a few of the factors that lead to the errors.

OneBusAway depends upon two types of data to tell you where your bus is: schedule data, which all about where and when the agency plans for each bus to be, and real-time arrival data, which is all about where the bus is right now. Schedule data is updated but several times a year. Real-time arrival data is updated constantly. Pull those two data types together and apply algorithms, and you've got a guess about when your bus will arrive. There can- and are- problems with both data types and with algorithms that lead to false predictions.

In the case of schedule data, various things can go wrong. It can be incomplete, as is the case with the current King County Metro data, it can contain errors, as is the case with all complex datasets, or it can just be missing- as is the case, for now, with Community Transit data. Also, since the data only lands a few times a year, but minor changes are made by agencies along the way- perhaps due to construction- it can be partially stale. And if a trip is canceled or rerouted, such as during a snow emergency, the schedule data can become desperately wrong.

Real-time (AVL, or automatic vehicle location) data is much more complex and fraught. Because the data is changing constantly, latency- a difference between when a data point is generated and when OneBusAway gets it- is a problem. Sometimes a trip goes missing due to technical issues, in which case only "scheduled departure" is shown. Some agencies don't even have real-time data (e.g. Community Transit). Complicating matters for King County Metro is the fact that they are transitioning from an older system based on a combination of radio beacons and wheel rotation counts to one based on GPS. (That process is about 60% complete, but there are yet more than 500 buses to be converted. Some areas are behind others, including the northern area of Seattle, where there is a high concentration of OneBusAway users.) The task of combining the two types of real-time data has proven to be challenging.

And then there are the algorithms. To predict an arrival, there is a lot to compute even after the position of a bus is known. For example, a mile of Montlake Boulevard at rush hour on Friday translates to a lot more time than that same mile two hours later. OneBusAway doesn't do its own arrival prediction- instead, we rely upon data from others, who in turn run their own or commercial software. This arrival prediction data comes from the agencies themselves for buses that use GPS; and from MyBus for buses using the older AVL system. (MyBus is a system running here at UW, from Dan Dailey and the Intelligent Transportation Systems project. A big thank-you to Dan and Joel Bradbury for continuing to keep this data up and available! OneBusAway has relied on it from the beginning, and will continue to do so while the AVL system is still in use.)

Finally, when buses are on reroute due to snow (as happened last month), the arrival predictions currently become somewhere between wildly inaccurate or totally missing.

Add up all these issues, toss in a snowstorm in January and simultaneous major schedule changes in mid-February, and you get a service that sometimes tells you lies.

The Future of OneBusAway

Dear riders,

Hi. We've not been properly introduced. My name is Brian and I'm the creator of OneBusAway. I'm a bus rider just like you and I started OneBusAway almost three years ago with the simple goal of making it easier to ride the bus. I'm also a grad student at UW getting my PhD in computer science. I managed to convince my advisors a while back to let me work on OneBusAway as part of my graduate research and things have been going well ever since.

Perhaps too well: there are now over fifty thousand of you using OneBusAway every week. That's an amazing number of riders for a grad student project. Of course, the trouble with grad students is that we sometimes actually graduate. Assuming my defense goes well a week from Thursday, that'll be my trouble too. The big question then is, "What's next?"

For me, I want to keep helping transit riders. Working on this project has been one of the most rewarding things I've ever done and I have no intention of stopping now if I can help it. What's more, I want to help riders world-wide, not just in Seattle. That and a lot of other reasons led me to my ultimate decision.

I'm going to work for Google. Specifically, the Google Transit team. If you've ever used Google Maps to plan a trip using public transit from point A to point B, then you're familiar with their work. Why Google? To put it simply, Google has done more to improve than usability of public transit than any other company I can think of. Their transit trip planner has made trip planning possible for hundreds of agencies where it wasn't before, and dramatically improved the trip planning experience for many agencies with planners of their own. What's more, projects like OneBusAway would not even be possible without the work of Google engineers. Their efforts to establish the GTFS spec for exchanging transit schedule data really launched the open transit data revolution that has lead to apps like OneBusAway and countless others. And perhaps you've heard they're getting into real-time?

What does that mean for you? My goal is that some day soon, you'll be getting all your transit info from Google. I'm sure some of you are skeptical of this goal, but I hope to change your mind. While I don't claim to speak for my future employer, Google already has some of the best tools anywhere for helping pedestrians, bicyclists, transit riders, and yes even car drivers, and they are only going to get better. I plan on doing everything > I < can to help that process along. And before I leave for Google this summer, I'm doing everything I can to make sure Puget Sound transit agencies are putting their best foot forward in terms of providing the data that powers services like OneBusAway and Google Transit. I won't say too much about that now, but in case you doubt my conviction, know that I'll be defending my dissertation and going through new employee orientation at King County Metro less than 24 hours apart. Dreams really do come true people ; )

In the meantime, we're not pulling the plug on OneBusAway the day I graduate. OneBusAway is NOT "abandoning Seattle". I'm doing everything in my power to make sure the lights stay on and while I can't say exactly what that will look like at this time, know that there are a number of options on the table and I'm confident we'll find a solution going forward.

As I've said before, working on OneBusAway has been an incredibly rewarding experience and it wouldn't be possible without the thousands of OneBusAway users like you. If you're anything like me, I know OneBusAway is a critical part of your daily commute (I don't even know how to get get home when OneBusAway is down). I'm doing everything I can in the future to keep building tools that help make using public transit a little easier for riders like you. While I can't promise exactly what that future will look like, all that I can ask is that you judge me by the work I've done as I pursue the work I hope to do.

Thanks,
Brian