Thursday, January 16, 2014

The Braess Paradox is Back and in New Scientist

This week I received a message from none other than Professor Dietrich Braess after whom the (in)famous paradox is named -- wherein adding a route to a transportation network can make the commute for all travelers longer! (Or, removing a road can get you to work faster!)

I am a big fan of Professor Braess' work and his paradox paper, which was written in German and published in 1968. I not only wrote about it in my doctoral dissertation, but have enjoyed building upon it  since.

Plus, I had the distinct honor, along with my doctoral students and the UMass Amherst INFORMS Student Chapter, of hosting Professor Braess' first visit to the U.S., back in April 2006, to speak specifically on his paradox.  In addition, we were celebrating the translation of his paper from German to English, which Braess and I did, along with my doctoral student from Austria, Tina Wakolbinger, who is now a Full Professor in Vienna. The translation was published in the INFORMS journal, Transportation Science, along with a preface, written by Professor David E. Boyce and me. 

The photos of Braess below were taken at the Isenberg School and at the University Club.
The photo immediately above was taken in my Supernetworks Lab at the Isenberg School. Professor Braess, Tina, and I are holding our translation in Transportation Science. Additional photos as well as a link to Professor Braess' presentation can be found on this page.

Professor Braess wrote me that New Scientist was writing a story on the paradox, which has just appeared and is by Justin Mullins. It is entitled: "42nd St paradox: Cull the best to make things better" and a preview is here.  I managed to access a copy, although the official publication date is not until January 18, 2014.  The article also notes Skinner's work vis a vis basketball and the Braess paradox, which I spoke about in the PBS America Revealed segment Gridlock (a great experience to be interviewed by the winner of Survivor in 2006, Yul Kwon!) and have written about on this blogNew Scientist also mentioned Professor Adilson Motter of Northwestern University, who led the recent Network Frontiers Workshop in December that I spoke at on Envisioning a Future Internet.Architecture.

Motter is quoted in  the New Scientist article on his ecology work (networks are everywhere!):  In certain circumstances,  the early removal of a species that would otherwise eventually go extinct anyway can prevent all secondary extinctions and improve the entire system's viability. That's an analogue of Braess's paradox, says Motter. 

The New Scientist article also talks about Professor Dirk Witthaut's work on the electric grid and concludes:  It is very early days in our understanding of biological networks. But if Motter, Witthaut and others have their way, counter-intuitive network effects may have a much more significant role to play in future. It may even be the key that helps the Knicks to another NBA play-off, and perhaps even reunites them with the championship trophy that has long eluded them.

And speaking of the Braess paradox, I have posted below a link to the video captured at the great UMASS Amherst TEDx event at which I spoke on The Traffic Circle of Life and, of course, the Braess paradox!

Anna Nagurney from TEDxUMassAmherst on Vimeo.

The lecture slides can be downloaded here.