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Posts Tagged ‘traffic’

How Drunk Is Too Drunk to Drive?

Our podcast “The Suicide Paradox” featured sociologist David Phillips, who spoke about his research on copycat suicides (a phenomenon he calls “the Werther Effect”). More recently, Philips has been studying drunk driving. Particularly, he’s been looking at drivers who are merely “buzzed” — with 0.01 percent blood alcohol concentrations (BACs) — and has found that the severity of life-threatening motor vehicle accidents increases significantly at BACs far lower than the current U.S. limit of 0.08 percent. In an email, Philips describes his latest research on buzzed drivers:

My current research, just published in Injury Prevention, shows that even minimally buzzed drivers (with BAC=0.01%) are 46% more likely to be blamed for an accident than are the sober drivers they collide with. This indicates that there is no safe level of alcohol for drivers: any amount of alcohol markedly increases the risk to drivers and their passengers. We reached this conclusion after examining an official, U.S. dataset of more than 570,000 car crashes. The findings have implications for drivers, passengers, police, judges, lawyers, insurance companies, advocacy organizations (like MADD) and regulatory agencies.


Do Game-Theory-Playing Traffic Lights Reduce Congestion?

That is what the headline of this fascinating article says. Here is a quote from the news report:

In lay language,” [Samah] El-Tantawy said in a U of T news release, “the [traffic lights] act as a team of players cooperating to win a game — much like players in a soccer match, where each player endeavors to score, but at the same time considers the ultimate goal of the entire team which is winning the match.

According to the article, travel times were reduced by 26 percent, which is fantastic, and which is what matters.

This doesn’t, however, seem to have much to do with game theory. Game theory is about one of two things: strategic behavior or finding sustainable equilbria. But the traffic lights don’t care about their own private utility.  There is no sense in which they are actors at all, as traffic lights just do what you tell them to do.  In economic terms, there is a central planner who sets the rules which the traffic lights obey. This new scheme provides a new and better set of rules (which, again, I emphasize is great), but I don’t think game theory should get the credit!

(Related: see our “Jane Austen, Game Theorist” podcast.)


Can the Right Music Get You Out of a Traffic Ticket?

Aaron Pilkington, an officer trainee at Air Force Officer Training School in Montgomery, Ala., writes to say:

I was driving down the road the other day with a fellow trainee, pointing out to him that the particular road along which we were driving always has police officers hiding out and catching people speeding. Just as I said that, sure enough, we saw a police car pull out with lights on and pull someone over.  My friend, Bill, said that he wondered if the song “Sweet Home Alabama” would work in Alabama. I asked him to elaborate.

My friend, who is from Rhode Island, explained that a couple of years ago he was speeding and got pulled over by a police officer.  He said that the song “Sweet Home Alabama” was on the radio and that somehow the officer let him off on a warning.  Some time later, he was pulled over again and had the song on his iPod.  In the time between being pulled over by the police officer and the officer walking up to his window, he pulled the song up on his iPod and left it on loud enough to be heard by the police officer, but not too loud.  Again, success.  He said this happened one more time just a couple of months ago in Florida and that he now always has at the ready a CD with the song “Sweet Home Alabama,” just in case he gets pulled over again.


The Nobel Prize in Physics and Traffic Priority at Roundabouts

The 2013 Nobel Prize in Physics was recently awarded for symmetry breaking and its consequence, the Higgs boson—a particle so well known that, according to the president of the American Physical Society, “[i]f you’re a physicist, you can’t get in a taxi anywhere in the world without having the driver ask you about the Higgs particle.” Teaching the symmetry unit in my own course this semester, I couldn’t help wondering about symmetry as I drove through an apparent example of symmetry: roundabouts or traffic circles.

Roundabouts use two complementary systems for controlling traffic flow: (1) Traffic in the roundabout has priority, or (2) traffic entering the roundabout has priority. The choice seems so symmetric, like choosing right- or left-hand traffic. In the United Kingdom, traffic in the roundabout has priority. In contrast, on many Massachusetts roundabouts, including one on my commute, entering traffic has priority.


Austin's New Toll Lanes

Traffic in Austin is a mess, mainly because the city is long and linear (east-west travel is made difficult by the topography). In increasingly long rush hours, traffic barely moves on either north-south freeway. To solve the problem, the city is adding one lane in each direction to one freeway, but there will be tolls on that lane. Moreover, the tolls will be variable — but not by time of day or day of week. They will vary with traffic speed, rising when the average speed in the lane drops below 50 mph. Pretty neat — peak-load pricing taken to its logical extreme. The technology that makes this possible is fairly recent. And it’s a good example of how technical improvements raise well-being — in this case, allowing those whose value of time is high to substitute money for their time and reducing congestion on the “free” lanes for the rest of us.


When Is It Inconsiderate to Press A Crosswalk Button?

I have no problem with pedestrians pressing crosswalk buttons when they wait for the crossing light to change before crossing the intersection.  Crossing lights and crosswalk buttons serve important safety function at busy intersections especially for disabled or elderly pedestrians who need a bit more time crossing the street.

But some pedestrians press the button with a conditional intention to cross the street before the crossing light changes if there is a break in the traffic.  One often sees pedestrians approach an intersection, press the button, and then immediately cross the street, before the crossing light changes. 

The pedestrian probably reasons a) “I have a right to press the button”;  and b) having pushed it, I now see I can walk without inconveniencing anyone because there aren’t any cars coming.


The Traffic Mimes

Our recent podcast “Riding the Herd Mentality” featured Antanas Mockus, the former mayor of Bogota, Colombia, who, among other unorthodox methods, hired mimes to tame the city’s unruly traffic. The mimes ridiculed bad behavior and handed out thumbs-up/thumbs-down cards to help people shame bad drivers.  Some photographic evidence:


Long Commutes: Bad for the Heart

A new study finds that, in addition to being a real downer, long commutes are related to bad health. Conducted by Christine Hoehner, Carolyn E. Barlow, Peg Allen, and Mario Schootman, the study found that long commutes are correlated with higher blood pressure and bigger waistlines.  “This is the first study to show that people who commute long distances to work were less fit, weighed more, were less physically active and had higher blood pressure,” said Hoehner. “All those are strong predictors of heart disease, diabetes, and some cancers.”


Traffic Pollution: A Silent Killer in the U.K.?

A new study claims that traffic pollution “is more than twice as deadly as traffic accidents.”  Scientists Steve Yim and Steven Barrett “estimate that combustion exhausts across the U.K. cause nearly 5,000 premature deaths each year,” writes Roland Pease. “The pair also estimate that exhaust gases from aeroplanes cause a further 2,000 deaths annually.”  The study also points out that pollution travels:

Of the 19,000 annual U.K. deaths estimated, 7,000 are due to pollutants blown in from the continent. In London, European pollutants add 960 deaths each year to the 2,200 caused by U.K. combustion fumes.

But the international trade in deaths goes both ways. More than 3,000 European deaths can be attributed to U.K. emissions the authors say.

Yim and Barrett estimate that premature deaths are costing the U.K. billions of dollars a year, and suggest reducing black carbon and nitrogen oxide emissions and investing in public transportation.

(HT: Naked Capitalism)


The Positive Effects of a Higher Alcohol Tax

Philip J. Cook and Christine Piette Durrance have published a working paper called “The Virtuous Tax:  Lifesaving and Crime-Prevention Effects of the 1991 Federal Alcohol-Tax Increase.” It makes a substantial argument for the upside of higher alcohol taxes:

On January 1, 1991, the federal excise tax on beer doubled, and the tax rates on wine and liquor increased as well. … We demonstrate that the relative importance of drinking in traffic fatalities is closely tied to per capita alcohol consumption across states.  As a result, we expect that the proportional effects of the federal tax increase on traffic fatalities would be positively correlated with per capita consumption. 


The Perils of Drunk Walking (Ep. 55)

In our latest Freakonomics Radio on Marketplace podcast, Stephen Dubner looks at why the first decision you make in 2012 can be riskier than you think. (Download/subscribe at iTunes, get the RSS feed, listen via the media player above, or read the transcript.)

The risks of driving drunk are well-established; it’s an incredibly dangerous thing to do, and produces massive collateral damage as well. So if you have a bit too much to drink over the holiday and think you’ll do the smart thing and walk home instead — well, that’s not so smart after all. Steve Levitt has compared the risk of drunk walking with drunk driving and found that the former can potentially pose a greater risk:


Does Marijuana Legalization Lead to Fewer Traffic Fatalities?

That’s the claim of a new paper by D. Mark Anderson and Daniel I. Rees, put out by the IZA, titled “Medical Marijuana Laws, Traffic Fatalities, and Alcohol Consumption”:

To date, 16 states have passed medical marijuana laws, yet very little is known about their effects. Using state-level data, we examine the relationship between medical marijuana laws and a variety of outcomes. Legalization of medical marijuana is associated with increased use of marijuana among adults, but not among minors. In addition, legalization is associated with a nearly 9 percent decrease in traffic fatalities, most likely to due to its impact on alcohol consumption. Our estimates provide strong evidence that marijuana and alcohol are substitutes.


Did Blackberry Outages Cut Abu Dhabi Traffic Accidents by 40 Percent?

A three-day Blackberry service outage last week in parts of the United Arab Emirates once again demonstrates the value of “distracted driving” laws. According to an article in The National, an English-language paper in Abu Dhabi, traffic accidents in Dubai last week fell 20 percent from average rates on the days when BlackBerry users were unable to use its messaging service. In Abu Dhabi, the number of accidents last week fell 40 percent, and there were no fatal accidents. According to the article, on average there is a traffic accident every three minutes in Dubai, and a fatal accident every two days in Abu Dhabi.

Abu Dhabi recently launched a campaign against cell phone use while driving and plans to use electronic evidence in traffic cases.


Raising MPG Standards: The Second-best Solution to a Gas Tax Increase

It got surprisingly little press coverage given the degree to which it will affect our lives (thanks, pesky world economic meltdown), but in case you missed it, the Obama administration recently worked out a compromise with the major automakers that will dramatically raise the corporate average fuel economy (CAFE) standards.
The new regulations mandate that the mix of new cars sold in the year 2025 must achieve about 54.5 miles per gallon (though if you read the fine print you’ll see that credits for various other green innovations mean that actual fuel economy will be more like 40 MPG.) For reference, the auto fleet currently on the road gets about 27 MPG. It’s a well-done agreement that will help avoid well-done citizens as global warming accelerates.
Before proceeding, let me note that I am strongly in favor of this policy. The problem of excessive fossil fuel use in transportation is multidimensional: if the issue of global warming doesn’t move you, the thought of Hugo Chavez and Mahmoud Ahmadinejad using our own hard-earned dollars to tweak our geopolitical noses should.
However, it is worth noting that raising CAFE standards is what political scientists and economists call a “second-best” solution; we could be doing considerably better if we thought all of this through more clearly.


Lottery Tickets for Safe Drivers?

Last month, Eric Morris wrote a post on red light cameras at traffic intersections in L.A. that sparked a robust debate in the comments section, something we always like. The debate centered around whether these devices are effective at reducing people’s willingness to run a red light, or whether they’re merely sources of revenue for the city. Perhaps you’ll feel similarly passionate about a new Australian study that examined the benefits of fixed speed cameras in New South Wales. From an ABC.net.au article:

On the whole [Auditor-General Peter Achterstraat] has found that speed cameras do change driver behavior and improve road safety but not in all cases. He has found 38 of the 141 fixed cameras across the state seem to have no significant benefit to road safety.


Bad Karma-geddon? Conjecture, Construction and Congestion in L.A.

L.A.’s “Carmageddon” is over. For those in the rest of the country, or Angelenos who spent the last two months trekking in Bhutan or in monastic seclusion, Carmageddon was the result of the complete closure of a major Los Angeles freeway over the weekend. The results?
Carmageddon was predicted by almost all journalists and government officials to be a brewing traffic nightmare of unprecedented dimensions. Only a day before the event I was reading predictions by our transportation authorities stating that traffic as much as 50 miles away would reach nightmare-like proportions. Only a very few, including myself, predicted we would see a situation of unusually light traffic reminiscent of the last time a similar situation happened: the 1984 Los Angeles Olympics.
In fact, Carmageddon saw stunningly low traffic levels, with many who did venture out reporting they had never driven at such speeds in LA in their lifetimes. Moreover, fears that the project (which involved demolishing half of a bridge over the highway) would drag on into Monday’s rush hour proved totally unfounded, as the work was completed and the freeway reopened on Sunday afternoon, many hours ahead of schedule.


A Solution to Car Accident Rubbernecking: Setting Screens

A few posts ago I wrote a piece about traffic incidents —some of them quite bizarre—that can cause road congestion. Many of these are due to reasonable or at least understandable causes; for example, we need to have road construction, although here in L.A. we wish we didn’t (more about our “Carmageddon” when the results come in.)
But perhaps the most galling and unnecessary source of incident-related congestion is “rubbernecking.” As we all know, terrific jams can be caused even when the wreck(s) is moved out of the traffic lanes, as passing drivers gape at the carnage. It’s been quite a long time since we shared a common ancestor with the vulture, but evidently an evolutionary tie is still there.
Rubbernecking is one of the more interesting cases of moral whipsawing I can think of. All the time we sit in the jam we curse the drivers in front of us for their blood lust. But when it’s our turn at the front of the line… well, just a quick peek.


L.A.'s Carmageddon: Would Building a Train Be Smarter Than Widening the 405?

The “mother of all traffic jams,” in the words of L.A. County supervisor Zev Yaroslavsky, is coming to Los Angeles. On the weekend of July 16/17, an 11-mile segment of Interstate 405 will be closed as part of a $1 billion widening project. Reading of the expected traffic jams, and having recently returned from western Europe, where I traveled mostly by train, I was reminded of an earlier traffic nightmare.
This example I learned from Robert Caro’s 1974 masterpiece The Power Broker: Robert Moses and the Fall of New York. Robert Moses was New York City’s “master builder” in the mid-20th century, and famously hated public transportation.


Seeing Red: Why L.A. Needs to Keep its Traffic Light Cameras

Thus far I’ve tried to avoid weighing in on the issue of red light cameras (RLCs) in an effort to keep my comments section free of any more angry posts than I normally get, and my email free of complaints from friends and relatives (you know who you are) who’ve been caught in the past. However, my hand has been forced by the Los Angeles City Council’s decision to consider a measure to eliminate our RLC program.
RLCs are not particularly popular. In fact, I have found that many people vehemently hate them. To give an example, the Chicago Tribune conducted a poll in 2009 showing that 53 percent of voters supported the cameras, while 41 percent opposed them. These percentages basically flipped when voters were asked if they wanted RLCs in their own neighborhood. This is a bit reminiscent of Monty Python’s proposal to “tax foreigners living abroad.”


Road Blocks: The Strange Things That Cause Traffic

The cause of a lot of the traffic congestion we battle everyday is pretty simple: too many people want to travel at the same time in the same direction to the same place, usually a job center. Since telework has been slow to replace the traditional workplace, it looks like this problem will be with us for a while.
For decades we have known about a way to deal with chronic congestion: levy tolls which vary depending on how crowded the road is. I’ve written about this here and here.
But pricing is not as well-suited for dealing with congestion related to unusual incidents, like breakdowns and wrecks. Even when these are relatively minor, incidents can start shock waves that cause serious amounts of delay as they ripple back through the traffic flow.


Does Destroying Highways Solve Urban Traffic Congestion?

Strange how the traditional laws of supply and demand go out the window when it comes to traffic. Studies over the last decade (like this one, this one, and this one; plus the book Suburban Nation) have pretty much dismantled the theory that more roads equal less traffic congestion. It turns out that the opposite is often true: building more and wider highways can increase traffic congestion. If only people like Robert Moses and Le Corbusier had known this before their grand urban plans left our cities clogged with traffic, and carved up by ugly, value-destroying highways.


Where on Earth Will All the Cars Go?

Evidence indicates that as national wealth rises, so does auto ownership. So what is going to happen when those in poor nations start buying cars at rich world levels? Can the world afford to have every Chinese and Indian driving a car?


Suicides Now More Plentiful Than Traffic Deaths

According to the National Highway Traffic Safety Administration’s (NHTSA) early projections, the number of traffic fatalities fell three percent between 2009 and 2010, from 33,808 to 32,788. Continuing what is now a 25 percent drop since 2005, when there were 43,510 traffic deaths.


How Do You Value Your Time?

Minneapolis allows single-occupancy cars to use its HOV expressway lanes for a price, which is typically between $1.50 and $2.50 on I-35W during morning rush-hour between the airport and downtown. The price seems to be higher when traffic in the other lanes is heavier — the city is sensibly applying peak-load pricing.


Communism and the Market

The Economist reports that the city of Shanghai has been auctioning car license plates. The average auction price has recently been $6,900, truly remarkable considering average family income in China, and even in Shanghai. The number of plates given out in 2011 will be reduced further in an attempt to reduce gridlock and pollution (both of which my experience several years ago in Shanghai suggests are world-class).


Should We Hope Congestion Gets Worse?

One of the less cheery parts of studying transportation is that the activity you have devoted your life to is widely considered an unmitigated downer. Even aside from the external environmental costs each trip places on society, travel is held to be no fun for the traveler. We don’t hop behind the wheel for the love of being honked at, cut off and stuck behind a creeping bus or semi; we endure travel only because we’ve got someplace to go. Right?


When That Child in the Street Is an Optical Illusion

Let’s say you live or work in an area where there are a lot of vulnerable pedestrians – kids, maybe – and a lot of cars as well, and that the cars habitually drive too fast for your taste.
What do you do?


A Traffic Jam Like No Other

If you think your commute is bad, take heart: a nine-day, 100-kilometer traffic jam recently befouled the Beijing-Tibet Expressway. It was reportedly caused by “maintenance construction,” although the road is often troubled by traffic.