Thursday, March 31, 2011

The Braess Paradox, Broadway, and Basketball

This blog post is being written as part of the monthly INFORMS blog challenge with the March challenge being "O.R. and Sports."

On March 15, 2011, after many discussions with a Public Broadcasting System (PBS) TV team about transportation, I ended up on Broadway in NYC for an interview and filming. A high level "script" had been prepared, which addressed not only a broad sweep of transportation and policies to alleviate congestion dating back to ancient times, but also more recent policies in Mayor Bloomberg's administration, including the removal of roads to traffic and the creation of pedestrian plazas as on Broadway from 47th Street to 42nd Street (see photos above). The script also included the meaning and importance of the Braess paradox, its relevance to the NYC transportation policies, and how this paradox continues to fascinate.

I was being interviewed and filmed for the PBS TV series: America Revealed, which will have segments on transportation, energy, and food, along with additional online video clips.

A few days before the video taping on Broadway, I was asked whether I could also comment on the relevance of the Braess paradox to basketball! Of course, it was March Madness time, and, although my interview will not be airing until next Fall, since this PBS production is an educational one, it is important to engage the audience, which is expected to include students from middle school, high school, and beyond, as well as the interested public, on related topics that might interest them.

To add to the excitement, at the lunch with the producer before the filming was to take place, I was told that my interviewer was Yul Kwon, the winner of the TV reality show, Survivor, in 2006. As I noted in an earlier post, he attributed his winning of the million dollar prize to his knowledge of game theory. He has degrees from Stanford and Yale, and was fantastic.

Now back to what the Braess paradox may have to do with the sport of basketball.

Recall that in the classical Braess paradox example, the addition of a new link to a transportation network, in the case of user-optimizing (selfish behavior), resulted in an increase in the travel time (cost) for all travelers in the network. Hence, in certain networks, the removal (or closure) of a road can actually improve travel time.

In the basketball world, according to Bill Simmons of ESPN, there is the Ewing Theory. According to Simmons: The theory was created in the mid-'90s by Dave Cirilli, a friend of his who was convinced that Patrick Ewing's teams (both at Georgetown and with New York) inexplicably played better when Ewing was either injured or missing extended stretches because of foul trouble. Simmons has a primer, Ewings Theory 101, which lists examples in basketball history where the removal of a top player (paradoxically) results in a better outcome for the basketball team.

Brian Skinner, a physicist at the University of Minnesota, wrote an article, "The Price of Anarchy in Basketball" in which he developed an analogy, through a model, between certain basketball plays and the Braess paradox, in order to further explore the Ewing Theory. You may find the preprint of the article here. You can also read a discussion of the specific play(s) on Skinner's blog.

How nice to be able to talk about game theory, the Braess paradox, and the relevance to even basketball, on Broadway, and to also get a chance to promote O.R.! The original Braess article was written in German, and, due to popular demand, Professor Braess, Dr. Tina Wakolbinger (who was then my doctoral student at the Isenberg School), and I did a translation of it to English, which was published in the INFORMS journal, Transportation Science in 2005!

Below is a photo of Professor Dietrich Braess with Tina and me in the Supernetworks Lab at the Isenberg School with the translation.

Professor Dietrich Braess visited us in April 2006 and also spoke in our Speaker Series.

Coincidentally, Tina, after receiving her PhD at UMass Amherst, joined the faculty of the University of Memphis, and when I gave talks there, I had the pleasure of meeting also with Coach John Calipari (Coach "Cal" had been the men's basketball coach at UMass Amherst in the 1990s and we have mutual friends). He is now Kentucky's men's basketball coach and his team, along with UCONN's, VCU's and Butler's have made it to the 2011 Men's Basketball NCAA Final Four!

Note the photo below with Coach Cal in his Memphis office back in the Fall of 2008 where he had a lot of UMass Amherst memorabilia. In fact, one of his daughters graduated from UMass and another one is still a student here.

As for Dr. Tina Wakolbinger, she will be joining the faculty of the Vienna University of Economics and Business as a Full Professor on May 15, 2011, and she received her PhD in 2007!

It will certainly be interesting to see who wins the 2011 NCAA basketball championship (both men's and women's)!