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Archive for the ‘Traffic Wonkery’ Category

System/Empathy in Transit

My latest Slate column considers Jarrett Walker’s new book Human Transit and the question of how we can make transit more successful: Make it nicer or more efficient (and do we have to choose)?

As befits someone who has spent decades in small, formerly smoke-filled rooms with civic officials trying to implement working transit systems, Walker is a realist, and Human Transit is a spirited guide—prescriptive but with a righteous dash of polemic—to what we get wrong about transit. “In many urban regions,” he writes, “support for public transit is wide but shallow.” People generally like the idea of transit (as characterized by the Onion headline, “98 Percent of Americans Support Public Transit for Others”), but much of our society’s experience and understanding of transit, not to mention our willingness to pay for it, is limited. The very fact that most of us drive, argues Walker, casts a subtle, but powerful, influence onto transit thinking. “In most debates about proposed rapid transit lines,” he writes, “the speed of the proposed service gets more political attention than how frequently it runs, even though frequency, which determines waiting time, often matters more than speed in determining how long your trip will take.” Drivers don’t wonder when their cars are going to show up.

The Economist picks up the thread over at its Democracy in America blog.

A lot of ink has been spilled over the past few years arguing about whether trolleys are silly atmospheric baubles or a vital ingredient of livable cities. Reading this passage, I abruptly realised why it is that I prefer taking my city’s rail-based transit to taking its buses: the presence of a dedicated rail serves as a visual promise of service. A bus stop stands forlornly in the urban wasteland, offering no real guarantee of the existence of the bus. The figure of the passenger waiting for a bus that may or may not ever arrive is a visual cliche. Trolley tracks and electric lines running down the middle of the street, however, are a promise: a line runs here. It may be ten minutes between trolleys, it may be half an hour, but something is going to come down that line and take you where you’re going. The very expense of creating the line tells you: the government has invested too much in this infrastructure for there to be no service. The rails are, literally, an ironclad guarantee.

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Posted on Tuesday, January 24th, 2012 at 2:19 pm by: Tom Vanderbilt
5 Comments. Click here to leave a comment.

Barnes Dance, RIP

The Barnes Dance is being phased out in the city where it was born (that’s right, Henry Barnes worked there before moving to NYC). It’s apparently a victim of (increasingly popular, it seems) light rail, which just goes to show how transportation planning for intersections, as one person once described it to me, is like apportioning a pie among a variety of hungry users — you can’t add to one share without taking away from somewhere else.

The full story is here.

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Posted on Friday, April 8th, 2011 at 12:50 pm by: Tom Vanderbilt
5 Comments. Click here to leave a comment.

Tweeting Traffic

My latest Slate column considers the role of Twitter in traffic.

Twitter provides a kind of a metaphysical traffic report, probing not just road conditions but the heretofore unconnected, if jammed together, society of the road. In one sense, this is strikingly appropriate: Twitter founder Jack Dorsey, as Vanity Fair has noted, was “fascinated by the haiku of taxicab communication—the way drivers and dispatchers succinctly convey locations by radio.” The service he proposed would bring that to everyone, enabling “a missing human element to the digital picture of a pulsing, populated city.”

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Posted on Monday, April 4th, 2011 at 9:04 am by: Tom Vanderbilt
4 Comments. Click here to leave a comment.

Infographic Traffic

Why Traffic Jams Happen width=
Via: Car Insurance Guide

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Posted on Friday, March 11th, 2011 at 5:22 am by: Tom Vanderbilt
14 Comments. Click here to leave a comment.

Some Dim

Over at Freakonomics, Steven Dubner wonders about the ethics of dimming headlights in the face of oncoming traffic (e.g., why do drivers perform this everyday altruism in the face of seemingly small consequences for not doing so). He also asks: “What I’d like to know is whether the benefit of dimming your headlights — that is, the benefit of not blinding the oncoming driver — is indeed larger than the benefit of keeping your own brights burning?”

This is a question that people who study vision and lighting and driving have thought about a lot. To summarize a conversation I had with Michael Sivak, at UM-TRI, there’s three distances involved here: The legally required distance to dim one’s lights in the face of oncoming vehicles, the optimal distance for maintaining one’s own visibility (and, I suppose, not blinding the other), and then what drivers’ actually do. Readers of this blog will suspect the last factor does not often match up with the two previous factors (and, I should add, as with many things in driving, the scientific issues around night-time illumination are much more complex than the “average expert driver” — i.e., everyone — realizes).

A paper by Kare Rumar expounds on this question:

From a pure visibility point of view, opposing drivers should never dim their lights, but should drive on high beam through the whole meeting process. There are, however, certainly other reasons for dimming the lights, such as discomfort glare and fatigue over a longer period with repeated high-beam meetings.

The study of Helmers and Rumar (1975) indicates that the improvements in the low beam since the fifties and sixties have been considerable. That is probably the main reason why the high-beam visibility curve and the low-beam visibility curve in later studies do cross each other—at least when the intensity differences between the two opposing high beams are not too large (about triple or less).

When the two opposing high beams differ substantially in intensity, the visibility differences between the two opposing drivers are quite pronounced (see Figure 3). In such situations, it is most probable that the driver with the weaker high beams will be the one who wants to initiate the dimming, because the driver with the weaker high beam experiences substantial disability and discomfort glare. On a straight, flat road, such a driver will want to dim the high beams at a very large distance between the vehicles.

An early dimming means that both drivers will have to drive on low beams for an extensive part of the meeting process. However, as stated above and illustrated in Figures 2 and 3, at larger separations low beams normally offer shorter visibility distances than high beams. This means that an early dimming leads to short visibility distances for a greater distance traveled, for both opposing drivers.

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Posted on Tuesday, September 28th, 2010 at 12:25 pm by: Tom Vanderbilt
11 Comments. Click here to leave a comment.

The Bayesian Road

From a new traffic-themed issue of Philosophical Transactions of the Royal Society, I was particularly interested in an article by Mark Campbell, et al., “Autonomous driving in urban environments: approaches, lessons and challenges.” As I discuss vis a vis Stanford’s “Junior” in Traffic, the perceptual and interaction dynamics of autonomous driving are infinitely complex. Here’s one bit, which follows a case study in which a vehicle had executed a maneuver that, while not being against the safety rules per se, were “still undesirable” — because, in essence, the vehicle, despite being equipped with formal Bayesian estimators and the like, had failed to take into account for what other vehicles might due. In other words, how do you program a vehicle to “expect the unexpected”?

In order for autonomous driving to reach its full potential, it is vitally important that the cars cooperate in the sense that they agree on traffic rules, whose turn it is to drive through an intersection, and so forth. For this, robust agreement protocols must be developed. Recent work on how to make multiple vehicles agree on common state variables, e.g. using consensus or gossip algorithm (Boyd et al. 2006; Olfati-Saber et al. 2007), provides a promising starting point for this undertaking.

When running such agreement algorithms, it is conceivable that not all vehicles will cooperate. They may, for example, be faulty, or simply driven by human operators, and such vehicles must be identified and isolated in order to balance autonomy with human inputs. This will be true on individual cars, but even more so in mixed human–robot networks. Questions of particular importance (that will have to be resolved using the available interconnections) include the following. (i) Safety: autonomous cars must be able to identify human-driven cars and then not drive into them even though they may violate the robot driving protocol. (ii) Opportunism on behalf of the human drivers: people are already driving badly on the road when the other cars are driven by people. How will they act if no-one is driving? This needs to be taken into account by the autonomous cars (i.e. not only will people not follow the ‘correct’ protocol—they might be outright hostile). (iii) Collaborative versus non-collaborative driving: how should non-cooperative vehicles be handled in an algorithmically safe yet equitable manner?

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Posted on Thursday, September 23rd, 2010 at 9:06 am by: Tom Vanderbilt
9 Comments. Click here to leave a comment.

Traffic and Algorithms in Seattle

Bill Beaty, the amateur “traffic waves” scientist described in Traffic, writes in to describe his early experiences with Seattle’s new Active Traffic Management System — the “dynamic” system of varying speeds, imported from Europe, which is meant to ameliorate the impact of drivers driving into vast stop-and-go traffic (with the ensuing shockwaves).

Beaty was curious to note that the first part of the project is happening on the very section of I-5 where he first began developing his one-man crusade for traffic harmonization. Here’s how he describes his new commute, which seems to have some of the disequilibrium that new schemes bring:

In the first week it created very strange patterns: huge I-5 jams on
Sunday (when Sunday I-5 northbound has always been empty.) They now seem
to be tweaking their algorithm. Or perhaps drivers are no longer freaking
out. Patterns are still odd, but keep changing over many days.

From what I can see, they’re trying to limit the inflow to the daily
northbound jam at I-5 and I-90 interchange. The result is a large
slowdown far south of the city, with an empty region right at the location
of the daily jam. Very odd to encounter a major slowdown near my own home,
where there never was congestion before …but then at the usual location
of the giant I-5 snarl, the traffic flows free at 50mph. Presumably there
no longer exists any continuously-growing daily jam. Merging at city
exits has suddenly become easy. Probably the old jam has been converted
into shockwaves moving slowly backwards, rather than the previously huge
region of 20mph driving.

Another ATMS section is on I-520 …which is right where I first saw the
string of headlights that inspired my first online article. Bizarre
coincidences. Or maybe the bigwigs in the Seattle traffic control
community have all been reading my site? :)

Any other Seattle-area readers/engineers care to share their experience?

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Posted on Thursday, September 16th, 2010 at 2:42 pm by: Tom Vanderbilt
2 Comments. Click here to leave a comment.

When SatNavs Attack

My latest Slate column is up, and it considers the emerging legal questions about liability in cases of crashes in which faulty GPS information is implicated.

And yet what happens when the world that is depicted is different from, or has not yet caught up to, the external world, and something goes awry? Where does the fault lie? Drivers, one might argue, should never rely entirely on a map—what family vacation hasn’t had its moments of (nonlitigable) high drama, with parents squabbling over a desert shortcut promised by Rand McNally that was washed out in the spring runoff? But there is a difference between glancing at a map for initial guidance (and then relying on signs or the road itself for information) and the new way of navigating, which is to receive authoritative real-time spoken and visual instructions—at a level of granularity measured in meters or feet—as one actually drives.

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Posted on Wednesday, June 9th, 2010 at 2:15 pm by: Tom Vanderbilt
3 Comments. Click here to leave a comment.

Selfish Routing, NBA Style

I wasn’t able to get up to the Sloan Sports Analytics Conference this year (though I wanted to, particularly as there were guys from Chelsea and Manchester United there), but as Traffic had both the Braess Paradox and Tim Roughgarden’s book The Price of Anarchy as touchstones, I was intrigued by a presentation from Brian Skinner, a physics professor at the University of Minnesota, which draws some parallels between network (in)efficiencies in roads and the running of successful basketball plays. The video above gives a short description but there’s more on offer at the paper (behind a pay wall):

Optimizing the performance of a basketball offense may be viewed as a network problem, wherein each play represents a “pathway” through which the ball and players may move from origin (the in-bounds pass) to goal (the basket). Effective field goal percentages from the resulting shot attempts can be used to characterize the efficiency of each pathway. Inspired by recent discussions of the “price of anarchy” in traffic networks, this paper makes a formal analogy between a basketball offense and a simplified traffic network. The analysis suggests that there may be a significant difference between taking the highest-percentage shot each time down the court and playing the most efficient possible game. There may also be an analogue of Braess’s Paradox in basketball, such that removing a key player from a team can result in the improvement of the team’s offensive efficiency.

(horn honk to The Transportationist)

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Posted on Friday, May 7th, 2010 at 4:20 am by: Tom Vanderbilt
2 Comments. Click here to leave a comment.

Asymmetric Information on I-95

In a footnote to Traffic, MIT’s Moshe Ben-Akiva discusses the varying strategies of dynamic tolling:

“You may want to charge people for time they actually save. That will mean if congestion builds up on the tolled road you reduce the price. On the other hand, you want to maintain a certain level of speed on the toll-road. If congestion builds up you want to increase the toll so as to not have stop-and-go traffic on the tolled road. There is some confusion going on right now as to what strategy is best.”

it seems that confusion is still out there, based on this dispatch from the Miami Herald.

Traffic engineers assumed high tolls would deter drivers from using express lanes. Wrong.

Many drivers, like Perkovich, assume high tolls mean the toll-free lanes are clogged. Could be true, but the tolls rise mainly due to the number of drivers willing to pay a toll.

Perhaps it’s not easy to make these decisions at high speed in a split second. Perhaps there’s some weird signaling effect going on in which higher prices lead to higher demand (for reasons of perceived quality or some other factor). Maybe the tolls aren’t high enough to deter drivers. Maybe the problem would vanish if drivers were given a more precise sense of time savings (as far as I know they are not). But South Florida drivers are not the first to be undeterred by higher tolls.

Before HOT lanes were launched on an I-10 commuter highway serving the Houston area, the Texas Transportation Institute based at Texas A & M University made an extensive study of driver attitudes and beliefs.

As many as 20 percent of the participants in several focus groups incorrectly interpreted the HOT lane toll as an index of traffic congestion in the free lanes, said Susan Chrysler, an institute research psychologist.

“Even after I showed them a video that explained it, they still misunderstood it,” Chrysler said. In Florida, DOT has responded with a crash public information campaign. A prominent message on the Express Lane website, 95express.com, clearly explains the system. And SunPass holders recently received a special mailing with the same message: higher tolls may mean a slower ride.

The market is still working, though perhaps not as rationally as might be hoped.

Despite the misunderstanding, the Express Lanes are easing traffic. Santana says the toll lanes are maintaining a comfortable 16 mile-an-hour speed advantage over the free lanes. A typical $2.50 to $3.00 rush hour toll usually buys a 45-mph drive between South Broward and downtown Miami, according to DOT data.

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Posted on Friday, April 2nd, 2010 at 2:22 pm by: Tom Vanderbilt
6 Comments. Click here to leave a comment.

The Vortex Junction

When I saw the headline, I thought it was referring to where the Santa Monica freeway intersects with the 405, but alas, it’s a novel interchange configuration, suitable for the Slough-ey, office-park-ey, pedestrian-free places of the world, perhaps some kind of next-century CFI.

(thanks Phil)

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Posted on Tuesday, March 30th, 2010 at 2:12 pm by: Tom Vanderbilt
5 Comments. Click here to leave a comment.

Mathematical Theorem Suggests Humans Really Are Sheep

As any Traffic reader knows I have a jones for “collective animal mobility.” I recently across an interesting paper, “Traffic and the visual perception of space,” by Petr Šeba, a physicist with the University of Hradec Králové in the Czech Republic.

As he notes:

During the attempt to line up into a dense traffic people have necessarily to share a limited space under turbulent conditions. From the statistical point view it generally leads to a probability distribution of the distances between the traffic objects (cars or pedestrians). But the problem is not restricted on humans. It comes up again when we try to describe the statistics of distances between perching birds or moving sheep herd. Our aim is to demonstrate that the spacing distribution is generic and independent on the nature of the object considered. We show that this fact is based on the unconscious perception of space that people share with the animals.

Here’s how it was done:

In order to verify this hypothesis we organized a simple experiment with pedestrians in a narrow corridor. Using two light gates we measured their velocity and the time interval that elapsed between two subsequent walkers. This enables us to reconstruct the mutual distances and evaluate the distance probability density. The same device and method was used also for a sheep herd moving through an aisle between two near yards. The third source of data are cars moving on a highway in a dense traffic. The velocity and time stamps of the individual cars were obtained by induction loops placed below the roadway.

The probability distribution of distances between objects in all these cases was essentially the same (suggesting, according to the author, a universal mechanism for estimating time-to-collision and its avoidance). Something to consider in those long holiday security lines at the airport.

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Posted on Tuesday, March 30th, 2010 at 8:11 am by: Tom Vanderbilt
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Transportation Economics in World of Warcraft

I came across this line in William Sims Bainbridge’s new book, The Warcraft Civilization, on the social sciences of the virtual World of Warcraft:

Some long-distance travel is free, using the public ship, zeppelin, or teleportation systems. But much flight from point to point has moderate costs. Maxrohn found that a nonstop flight from Light’s Hope Chapel in Eastern Plaguelands to Nethergarde Keep in the Blasted Lands costs thirty-one silvers and fifty nine coppers. However, it is possible to fly from Light’s Hope to Stormwind for nine silvers and sixty-three coppers, and from Stormwind to Nethergarde for seven silvers and forty-seven coppers. Thus, stopping at Stormwind saves fourteen silvers and forty-nine coppers, or slightly over 45 percent.

It’s intriguing that this rather echoes the market for using frequent-flier points — i.e., it will cost you less for a flight with stops. This raises all kinds of interesting questions: What dynamics account for the pricing (e.g., does greater network traffic increase the cost of travel) and the network disequilibrium? Why would anyone pay to travel if one can teleport for free (a question for Patricia Mokhtarian)? Is there a Kayak-type application for analyzing the costs of travel, or is it all trial and error? Do people interact on the public ships and zeppelins? Is private flight much faster than the public options (presumably teleportation is instantaneous), and is there a “last mile” or connectivity problem with the public options (so to speak)? And lastly: Are there any travel externalities in World of Warcraft?

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Posted on Wednesday, March 24th, 2010 at 12:34 pm by: Tom Vanderbilt
7 Comments. Click here to leave a comment.

Higher Learning

Mary Beard notes the new biblio-themed bollards outside of University Library at Cambridge University. Alas, no titles, as she notes, but certainly inspired, and hinting at the tremendous untapped potential of the bollard form.

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Posted on Wednesday, September 23rd, 2009 at 3:20 pm by: Tom Vanderbilt
2 Comments. Click here to leave a comment.

The Express Lane Isn’t Faster

Reader Mike had sent along this great post from a California math teacher who analyzed supermarket checkout times (data, as pictured above, was provided by the supermarket manager). I’m slow to post this and it has now been around a lot, but this was catnip to me as I love these sort of operational/logistical/queue problems (and this relates a bit to the airport walkway problem), particularly when they seem to exhibit that classic “slower is faster/faster is slower” effect. Not to mention that “other lane is always moving faster” problem that plagues us in traffic is a very real issue in queuing as well (and is partially why some outfits use single lines).

Among the many interesting findings:

The express lane isn’t faster. The manager backed me up on this one. You attract more people holding fewer total items, but as the data shows above, when you add one person to the line, you’re adding 48 extra seconds to the line length (that’s “tender time” added to “other time”) without even considering the items in her cart. Meanwhile, an extra item only costs you an extra 2.8 seconds. Therefore, you’d rather add 17 more items to the line than one extra person! I can’t believe I’m dropping exclamation points in an essay on grocery shopping but that’s how this stuff makes me feel.

There’s ways this can be applied to traffic, but reader Mike was wondering about those express/local lanes on highways. I only know anecdotal stuff here, like stories of engineers changing the estimated times on both segments when they really want people to use one or the other. But this is a bit of a guessing game every time I approach the George Washington Bridge on I-80. I’ve been burned many times by the express lane — is it the very wording, which fools me into thinking it’s a better way to go than that inevitably cluttered and slower “local” lane? It of course depends on many variables, like the intended destination of traffic, etc.

Maybe there’s some geeky studies somewhere of tolling as well; exact change lanes versus others, etc.; though those are likely to be outmoded with EZ-Pass etc.

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Posted on Tuesday, September 22nd, 2009 at 9:36 am by: Tom Vanderbilt
3 Comments. Click here to leave a comment.

If You Can’t See My Mirrors

Though I didn’t see the above fine specimen represented, my pal Phil Patton’s treatise on the graphic design of truck warning stickers is well worth a read. Unlike so many other segments of road safety, it is utterly unstandardized, and filled with interesting variation.

That raises an interesting point, how warning someone about the same hazard can involve different strategies. One way is to simply say DON’T, without further explanation. Graphically, this is represented by the classic circle and slash over an icon representing an activity. But another way is to show the consequences of an act. You can warn people away from a behavior by depicting its results. Think of the dramatic arched back of a person in the throes of electrocution in some signs. Verbally, a famous case of this approach is the mother’s classic warning about the Red Ryder B-B gun her son dreams of, in the 1983 film A Christmas Story: “You’ll shoot your eye out!”

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Posted on Tuesday, September 1st, 2009 at 4:21 pm by: Tom Vanderbilt
1 Comment. Click here to leave a comment.

The Taking of Pelham’s Trees

Apparently this issue has been around awhile. From a letter to the New York Times, 1999:

To the Editor:

Re ”Drivers Fear Leafy Menace by the Side of the Road” (Sept. 19): Pelham Parkway is not a limited-access highway; it is a parkway, a road that connects Pelham Bay Park with Bronx Park. Coincidentally, it now connects the Bronx River Parkway with the Hutchinson River Parkway and the New England Thruway (I-95). It was designed for light pleasure traffic at speeds of 25 to 30 miles per hour, not 50 to 60 m.p.h.

When people fall asleep at the wheel, are cut off by another vehicle or seek to avoid an animal in the road and hit one of the trees transplanted from the subway construction on the Grand Concourse, it is not the fault of the tree, nor the design of the road. I would hate to see the trees removed simply because motorists are not observing the speed limit.

If the police would enforce the speed limit on Pelham Parkway, the city would make money on the road instead of spending it. If the road could have been redesigned, you could be sure the master builder (and destroyer) Robert Moses would have rebuilt it after his failure to complete the Sheridan Expressway, which would have been the main east-west roadway to compliment the Cross Bronx Expressway.

THOMAS VASTI JR.

Morris Park, Bronx

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Posted on Wednesday, August 26th, 2009 at 8:36 am by: Tom Vanderbilt
2 Comments. Click here to leave a comment.

Left on White

Reader Francisco sends along, via Shorpy, an image sure to delight the ranks of historical traffic signal enthusiasts (that’s the Washington, D.C. traffic director inspecting the hardware circa 1926)

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Posted on Thursday, July 30th, 2009 at 11:56 am by: Tom Vanderbilt
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Red Yellow Green

In Traffic I make a passing mention of the evolution of traffic light sequences:

Others wanted the yellow light shown before the signal was changing to red and before it was changing from red back to green (which one sees today in Denmark, among other places, but nowhere in North America).

Reader Claire writes in to note that she remembers this sequence being used in the U.S.:

I distinctly remember passing through signals of this type on arterial streets in Chicago between 1977 – 1983. They were mostly located west of the L tracks on arterial streets like Belmont, Armitage, Fullerton, Devon, and Ashland.

Now, I didn’t say they were never used in the U.S., just that they aren’t anymore — although I may be wrong here and I’d be curious to see an example. She helpfully points us to Willis Lamm’s Traffic Signal page, which contains video examples of these “really funky signal phases.”

I’ve seen international studies on the potential problems with the red-amber-green phase, but haven’t really heard or read an account of why these phases vanished in the U.S. (though I’m sure the information is out there, in some back issue of the ITE Journal). I can imagine there are pedestrian issues, not to mention intersection clearance issues. And given that hardly anyone drives a manual shift in the U.S., one of the perceived virtues of that system is now largely lost here, like an old piece of slang no one uses anymore.

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Posted on Tuesday, July 14th, 2009 at 12:01 pm by: Tom Vanderbilt
9 Comments. Click here to leave a comment.

Le Rond

The above image is one of a series of roundabouts photographed by Kleinefenn, a German-born photographer living in France. The complete collection is here, and will leave traffic geeks heads spinning in wonder.

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Posted on Monday, July 6th, 2009 at 3:45 pm by: Tom Vanderbilt
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Traffic Tom Vanderbilt

How We Drive is the companion blog to Tom Vanderbilt’s New York Times bestselling book, Traffic: Why We Drive the Way We Do (and What It Says About Us), published by Alfred A. Knopf in the U.S. and Canada, Penguin in the U.K, and in languages other than English by a number of other fine publishers worldwide.

Please send tips, news, research papers, links, photos (bad road signs, outrageous bumper stickers, spectacularly awful acts of driving or parking or anything traffic-related), or ideas for my Slate.com Transport column to me at: info@howwedrive.com.

For publicity inquiries, please contact Kate Runde at Vintage: krunde@randomhouse.com.

For editorial inquiries, please contact Zoe Pagnamenta at The Zoe Pagnamenta Agency: zoe@zpagency.com.

For speaking engagement inquiries, please contact
Kim Thornton at the Random House Speakers Bureau: rhspeakers@randomhouse.com.

Order Traffic from:

Amazon | B&N | Borders
Random House | Powell’s

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U.S. Paperback UK Paperback
Traffic UK
Drive-on-the-left types can order the book from Amazon.co.uk.

For UK publicity enquiries please contact Rosie Glaisher at Penguin.

Upcoming Talks

April 9, 2008.
California Office of Traffic Safety Summit
San Francisco, CA.

May 19, 2009
University of Minnesota Center for Transportation Studies
Bloomington, MN

June 23, 2009
Driving Assessment 2009
Big Sky, Montana

June 26, 2009
PRI World Congress
Rotterdam, The Netherlands

June 27, 2009
Day of Architecture
Utrecht, The Netherlands

July 13, 2009
Association of Transportation Safety Information Professionals (ATSIP)
Phoenix, AZ.

August 12-14
Texas Department of Transportation “Save a Life Summit”
San Antonio, Texas

September 2, 2009
Governors Highway Safety Association Annual Meeting
Savannah, Georgia

September 11, 2009
Oregon Transportation Summit
Portland, Oregon

October 8
Honda R&D Americas
Raymond, Ohio

October 10-11
INFORMS Roundtable
San Diego, CA

October 21, 2009
California State University-San Bernardino, Leonard Transportation Center
San Bernardino, CA

November 5
Southern New England Planning Association Planning Conference
Uncasville, Connecticut

January 6
Texas Transportation Forum
Austin, TX

January 19
Yale University
(with Donald Shoup; details to come)

Monday, February 22
Yale University School of Architecture
Eero Saarinen Lecture

Friday, March 19
University of Delaware
Delaware Center for Transportation

April 5-7
University of Utah
Salt Lake City
McMurrin Lectureship

April 19
International Bridge, Tunnel and Turnpike Association (Organization Management Workshop)
Austin, Texas

Monday, April 26
Edmonton Traffic Safety Conference
Edmonton, Canada

Monday, June 7
Canadian Association of Road Safety Professionals
Niagara Falls, Ontario

Wednesday, July 6
Fondo de Prevención Vial
Bogotá, Colombia

Tuesday, August 31
Royal Automobile Club
Perth, Australia

Wednesday, September 1
Australasian Road Safety Conference
Canberra, Australia

Wednesday, September 22

Wisconsin Department of Transportation’s
Traffic Incident Management Enhancement Program
Statewide Conference
Wisconsin Dells, WI

Wednesday, October 20
Rutgers University
Center for Advanced Infrastructure and Transportation
Piscataway, NJ

Tuesday, March 8, 2011
Ontario Injury Prevention Resource Centre
Injury Prevention Forum
Toronto

Monday, May 2
Idaho Public Driver Education Conference
Boise, Idaho

Tuesday, June 2, 2011
California Association of Cities
Costa Mesa, California

Sunday, August 21, 2011
American Association of Motor Vehicle Administrators
Milwaukee, Wisconsin

Wednesday, October 26, 2011
Attitudes: Iniciativa Social de Audi
Madrid, Spain

April 16, 2012
Institute for Sensible Transport Seminar
Gardens Theatre, QUT
Brisbane, Australia

April 17, 2012
Institute for Sensible Transport Seminar
Centennial Plaza, Sydney
Sydney, Australia

April 19, 2012
Institute for Sensible Transport Seminar
Melbourne Town Hall
Melbourne, Australia

January 30, 2013
University of Minnesota City Engineers Association Meeting
Minneapolis, MN

January 31, 2013
Metropolis and Mobile Life
School of Architecture, University of Toronto

February 22, 2013
ISL Engineering
Edmonton, Canada

March 1, 2013
Australian Road Summit
Melbourne, Australia

May 8, 2013
New York State Association of
Transportation Engineers
Rochester, NY

August 18, 2013
BoingBoing.com “Ingenuity” Conference
San Francisco, CA

September 26, 2013
TransComm 2013
(Meeting of American Association
of State Highway and Transportation
Officials’ Subcommittee on Transportation
Communications.
Grand Rapids MI

 

 

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