Counter-intuitive idea counters traffic gridlock 

Heavy traffic and gridlock are a big problem in most major metropolitan areas, perhaps none more prominent than Manhattan. Yet, when NYC Mayor Michael Bloomberg closed parts of Broadway in 2009 to motorized vehicles, the flow of traffic in the surrounding area actually improved. How can that be?

The counter-intuitive credit should go to German mathematician Dietrich Braess, whose Braess Paradox states that, “Adding extra capacity to a network when the moving entities selfishly choose their route, can in some cases reduce overall performance. This is because the Nash equilibrium of such a system is not necessarily optimal” [Wikipedia].

Manhattan is famous for a lot of things – Wall Street, fashion, musical productions, museums, restaurants, parades, Central Park and, of course, absolutely fabulous celebrities and their fabulously expensive domiciles. On the downside, Manhattan is also known for its horrendous traffic, a topic the PBS production “America Revealed” addresses in an upcoming four-part series scheduled to begin April 11. A segment on transportation features University of Massachusetts-Amherst Professor Anna Nagurney, who explains the Braess Paradox while walking down Broadway at Times Square with show host Yul Kwon.

Nagurney, an active member of the Institute for Operations Research and the Management Sciences (INFORMS), helped translate the Braess Paradox from German to English for an article in Transportation Science. A network expert, Nagurney reveals during her PBS appearance how mankind has wrestled with traffic since the Roman Empire and suggests that the solution might lie in an unlikely direction: removing options for drivers rather than adding new roads.

Transportation planners in Manhattan are putting that theory to the test by removing traffic from one of the city’s busiest stretches.

To see Nagurney’s PBS video segment, click here.