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Traffic decongestion projects at home and abroad

October 03, 2013

(From the left) Angus Davol, former Transporation Program Developer/ Planner at Stanford P&TS; Professor Balaji Prabhakar

Balaji Prabhakar

If you are looking for an incentive for going green at Stanford, join Congestion and Parking Incentives (CAPRI), a new commuting program, focused on peak commuters. Launched in April 2012, almost 4,000 Stanford people have registered on this pilot project and over $75,000 has been paid out as incentives so far. Professor Prabhakar, lead investigator of CAPRI and professor of electrical engineering and computer science, has previously tested his project to mitigate traffic congestion during peak commuting hours in Bangalore, India and Singapore.

Q. How did you start your project in Bangalore, India?

BP: My research focus is on computer networks, not transportation. I was in Bangalore to visit Infosys Technologies and experienced terrible traffic congestion on my way to the company.  I brought this up with my host at Infosys and we started corresponding via emails regarding the problem. Infosys Technologies had over 200 chartered buses used for their commuters, and we conducted a detailed analysis of the data on their commuters’ use of the buses. This developed into an incentive program to nudge their commuters to travel off-peak. We launched the program with support from the management of the company. The program ran for six months and was successful in nearly doubling the number of off peak commuters. You can find more details about the project at our paper, An Incentive Mechanism for Decongesting the Roads: A Pilot Program in Bangalore.

At Stanford, approximately 15% of peak time commuters moved to off-peak hours."

Q. How is your approach different from other incentives at Stanford?

BP: Parking and Transportation Services at Stanford has offered a number of incentives to encourage people not to drive in. This has done a great job of reducing the overall traffic.

Our program is focused on peak traffic. Specifically, we only incentivize trips made in the off-peak shoulder hours. A second difference is we offer random “lottery-like” rewards through a fun game interface. This amplifies the amount of money a participant can win and has proven to strongly influence behavior shifts. Third, we have a social component: participants can see their friends’ performance and rewards, and this has proven to have a strong effect on their own performance. Finally, we also offer personalized recommendations and prizes on a weekly basis.

Q. You had a pilot project abroad and then brought it back to Stanford, which is quite interesting. How did you come up with CAPRI based on your pilot project abroad?

BP: After the initial project in India, our team simultaneously proposed the approach to Singapore and the Department of Transportation in the United States. After being approved by both, the project in Singapore launched first in January 2012 as a Frequent Commuter Program targeting commuters who take public transit. In this program, called INSINC, commuters earn points for every kilometer traveled with three credits per kilometer traveled in the off-peak times. At the end of the first 6 months, INSINC reduced peak trips by about 10%. The program has since been extended to include more commuters. These positive experiences in Bangalore and Singapore gave us a good understanding of commuter behavior, and the technological platform on which Capri runs borrows heavily from INSINC.

Q. What were the consequences for the projects in different locations? Were there any differences among them in terms of results?

BP: Our approach led to significant changes in commuter behavior in all three places. Based on our analysis of previous and ongoing pilot projects, we believe that traffic congestion is a universal phenomenon and our solution is applicable in any city around the world, as long as it is equipped with relevant technology and infrastructure.

In India, the Infosys program doubled the number of its off-peak commuters in six months. Unfortunately, a lot of employees went back to their previous commuting behavior after the incentive program concluded. This tells us that such incentive programs need to run longer to make a long-term change. In Singapore, about 10% of peak time commuters shifted to off-peak commuting hours. We analyzed how demographic, social, gender and other various criteria might have affected the commuters’ behaviors. The results of the research will be published in JOURNEYS, a journal produced by Singapore’s Land Transportation Authority (LTA) Academy.

At Stanford, I believe approximately 15% of peak time commuters moved to off-peak hours. We don’t have the exact data because there is no information about Stanford commuters’ behavior before participating in CAPRI. However, in spring of 2011, the number of auto commuters during evening peak hours exceeded the maximum amount allowed by Santa Clara County. In 2012 after CAPRI launched, Stanford was under the limit by 200 cars. We cannot tell how much CAPRI had contributed to the decrease, but I believe that there has been some impact.

Q. Who were the local collaborators for your projects abroad and at Stanford?

BP: In Bangalore, the management at Infosys Technologies provided thorough data on their bus commuters’ behaviors and technological infrastructure to implement the project. In Singapore, two faculty members at the National University of Singapore as well as Land Transport Authority (LTA) were very engaged with the project.

At Stanford, Parking and Transportation Services (P&TS) has been deeply involved in Capri, and Provost has been very supportive of the project. Most importantly, I have a pleasure of working with Stanford students who are enthusiastic about the solution.  

Q. Do you have any other cities in mind to apply your solution? Can you also tell me how you are going to develop CAPRI at Stanford?

BP: We are discussing possibility with different cities in Europe and Latin America. Some of them approached us to work with us, others are just curious.

Within the campus, we are planning to expand the incentive to drivers who use less crowded parking lots. We are also talking with possible collaboration with BeWell program for those who bicycle or walk to campus. Since the programs need to be designed very carefully, it may take time to launch them.

Q. What is your long-term goal for decongestion solution?

BP: As I mentioned earlier, everybody commutes, twice a day. I think that in a modern society, congestion and water shortage are the most frequently encountered urban problems. Some places are blessed with lots of water, but when it comes to commuting, no one is exempt. Congestion and emissions are problems every city around the world must face. Unfortunately, they are getting worse, not just because population is increasing but also because the number and proportion of people living in cities is increasing. Therefore, sharing resources will be our future. I believe that there must be meaningful ways to help that sharing happen. Thus, we would be happy to collaborate with anybody around the world who is interested in our effort.

* CAPRI has been terminated as of 2014. Thank you very much for your attention.