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Further proof our roads make no sense

Three physicists claim that shutting certain Boston roads at rush hour could actually improve traffic flow. Unfortunately, we'll have to wait for the next issue of Physical Review Letters to learn which roads. In the meantime, we have this synopsis from the Economist of the paper by Hyejin Youn and Hawoong Jeong, of the Korea Advanced Institute of Science and Technology, and Michael Gastner, of the Santa Fe Institute, who spent quite a bit of time analyzing traffic flows in Boston, London and New York. Locally, they looked at different ways to get from Harvard Square to Boston Common:

... Modifying the road network could reduce delays. And contrary to popular belief, a simple way to do that might be to close certain roads. This is known as Braess's paradox, after another mathematician, Dietrich Braess, who found that adding extra capacity to a network can sometimes reduce its overall efficiency.

In Boston the group looked to see if the paradox could be created by closing any of the 246 links. In 240 cases their analysis showed that a closure increased traffic problems. But closing any one of the remaining six streets reduced the [total commute time] of the new Nash equilibrium.

Via John Keith.

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Drivers are not rational.

Ever been in a highway traffic jam that suddenly clears up and theres just open road? (of course you have)

Ever taken a longer route because theres no traffic, even if it takes the same amount of time? (yes)

Thats why urban design isnt all about models, but psychiatric stuff too

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Most models take driver behavior into account. If they don't, then you are correct. But some of that behavior can be regressed or smoothed - it can be accounted for by the model in a general way without explicit enumeration of specific variables.

I will probably track these guys down once the papers come out - I might want them for a conference panel on congestion charging, and may want to link them with the GIS folks who model air pollution from traffic sources.

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"Most models take driver behavior into account"

I'm not sure about. I think that the poor designing and planning of many, if not most of our roads, streets, highways, and traffic routing management tends to produce much of the driver behaviour that's been present on our roads for several decades.

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No kidding, right? This happens, then you don't see an accident, and you think "what the fuck?"

Problem is dipshits who don't let people merge onto the highways. Get to the left at exits, you stupid fucks. This is why you don't pass people on the right.

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Just wow.

It never ceases to amaze me the amount of venom that driving can generate in a person. So glad I don't own a car.

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