August 2008 Archives

California High Speed Rail Blog: Taking the Coast Route purports to discuss The Transportation Experience.

It might be worth reading the book The Transportation Experience to see what Garrison and Levinson (i.e. me) actually think.

(And in contrast to the blog-author's assertion, both gas prices and global warming are addressed as issues, with possible solutions considered).

HSR rail is ultimately gussied up rail technology, which has its niche in high density areas with available Right-of-Way (and no intervening mountain ranges). The book, and another book by Garrison, do describe other technologies that hold some promise, but this book is primarily about understanding the historical process of transportation development, and why it creates the problems we have.

The blog author here is clearly imposing his imagined assumption of conventional opposition onto Prof. Garrison, who is a very out-of-the-box thinker, who does not fall into the traps that swallow either of the ends on the conventional axis (pro-auto, pro-rail) .

There are several other issues here
Certainly $4/gallon gas is more expensive than $3/gallon gas, but we are not talking about a project (California HSR) that is even marginally cost-effective.

The cost (and energy used) in construction will be enormous.

The rail, as all transportation projects, will promote sprawled development in the Central Valley which will now be in commuting range of the Bay Area or metropolitan LA.

The question is not whether this is a project which is beneficial (which it is not), but whether it is the best use of scarce funds (which it most certainly is not). If you had $40 Billion to spend on transportation in California, what would you do, what would serve the most people the best.

Granted air travel is not terribly convenient, but once the same security apparatus is imposed on HSR (and it will be), HSR will not be the simple urban transit-like (or even Amtrak-like) experience fans would wish for.

Some more pictures from Fail Blog, these on parking miscues. A combination of design errors and user errors.

From Strib: Extra lanes on I-94 won't disappear. MnDOT is going to study making them managed or HOT lanes, extending the MnPass network potentially (which already includes I-394 and will soon have I-35W thanks to the Urban Partnership Agreement).

A comparison of Obama and McCain's positions on transportation from Bookings: Candidate Issue Index: Transportation

In the NYT, an article about the (relative) popularity of natural gas cars in Utah: Surge in Natural Gas Cars Has Utah Driving Cheaply

Natural gas still is hardly dominant, but suggests with the right economics (cheap natural gas, expensive petrol), a fleet conversion is plausible.

The longer article in the Pioneer Press: Bridge collapse didn't stall commutes, U study finds -

Bridge collapse didn't stall commutes, U study finds
University of Minnesota report shows times up only slightly
By Jake Grovum
jgrovum@pioneerpress.com
Article Last Updated: 08/28/2008 11:51:43 PM CDT

A year after the Interstate 35W bridge collapse, the average Twin Cities car trip has increased by less than a minute, according to a University of Minnesota study.

The average trip before the bridge collapse was 18.6 minutes, according to the study by University of Minnesota associate civil engineering professor David Levinson. After the collapse, drive time grew by two-tenths of a minute, to 18.8 minutes.

Other studies indicate the commute time to work and back also grew only less than a minute, Levinson said.

In fact, for the majority of the estimated 150,000 motorists who crossed the eight-lane bridge daily — even those now driving in heavily-trafficked areas — the time hasn't changed much at all. Some have even seen shorter commutes, the study found.

The reason?

Despite almost 100,000 more cars using Minnesota 280 and 35,000 more cars on Interstate 94 between 280 and I-35W each day, the infrastructure in the metro area is designed to withstand those increases.

Commuters did get help from emergency road improvements after the collapse. An extra I-94 traffic lane was added in each direction between downtown Minneapolis and 280, while two intersections with stoplights were closed on 280 and most ramps were widened or modified for better traffic flow.

Levinson surveyed those affected by the collapse, monitored vehicle counts and used models to analyze post-collapse traffic.

It's not an issue of people driving less, Levinson said, because traffic levels have been steady for the past year. Despite the collapse and an increase in gas prices, the number of commutes is about the same.
Still, comparable before and after commute times might not be comforting to commuters. Prior to the collapse, the I-35W and I-94 interchange was one of the most heavily congested areas in Minneapolis.

Immediately after the collapse, two main Minnesota Department of Transportation detour sites, 280 to I-94 and Interstate 694 to Interstate 394, endured "severe congestion" and every remaining bridge crossing the Mississippi River became more crowded, according to Levinson's research, but the improvements helped accommodate motorists.

"Those made those facilities operate pretty well," Levinson said. "Had those improvements not been made, things would be a lot worse."

Not everyone is getting around so easily.

Lisa Sweet commutes from Roseville to Plymouth. She plans to sell her house and move closer to her job after seeing an extra 30 minutes tacked onto her drive.

"The commute right away was pretty tough," she said. "(Now) they're choosing to drive different ways so the traffic is spread out."

Sweet has a number of routes she uses, but some take longer than others. Those in her office have been sharing tips for navigating the post-collapse roadways, Sweet said, adding that I-694 "isn't great on Fridays."

Brian Kary, MnDOT freeway operations engineer, said commute times went "up significantly" immediately after the bridge collapse but said that after the improvements, most commute times were "comparable," particularly on I-94.

Still, Levinson's research seems at odds with a 2008 MnDOT report examining congestion in the metro area. That study found a 40-mile increase in total congested miles (a mile of traffic moving slower than 45 miles per hour) for the first time in four years in 2007, citing the bridge collapse as a reason for the "dramatic" increase.

But MnDOT expects to see "significant congestion relief" when the new 10-lane I-35W bridge is complete, according to its report, although it's unclear whether the supplemental road improvements will be permanent, Kary said.

Our traffic effects of the bridge collapse study made AP: Study finds traffic not bad after bridge collapse

From the Pioneer Press:

Minnesota News
Study finds traffic not bad after bridge collapse
The Associated Press
Article Last Updated: 08/29/2008 06:27:12 AM CDT

MINNEAPOLIS—A University of Minnesota study shows that car trips in the Twin Cities are less than a minute longer than they were before the Interstate 35W bridge collapse.
Civil engineering professor David Levinson looked into the Twin Cities drive times and found that the average trip before the collapse was just two-tenths of a minute faster.

Levinson says other studies have shown that work commute times are also less than a minute longer.

Part of the reason is emergency road improvements on Minnesota 280 and Interstate 94. But Levinson also says the infrastructure in the Twin Cities was designed to handle an increase.

While severe congestion occurred immediately after the collapse, traffic flow improved with the changes.

The new Interstate 35W bridge is set to be open as early as next month.

An article appears in the magazine Miller-McCune by Ryan Blitstein Derailing the Boondoggle, which discusses Bent Flybjerg, reference-class forecasting, and the trouble with mega-projects.

Clearly engineering based estimates of project costs built up cubic yard by cubic yard ought to be compared with economic-based estimates of the costs of the same project using comparable cases. Similarly for demand forecasts. Ideally the two methods (economic and engineering) would be the same, or close. Practice indicates otherwise.

One wonders whether estimates showing benefits < costs would actually derail many of these projects. Hiawatha LRT in Minnesota had a published B/C ratio of 0.42 and went forward and is now heralded (politically) as a success. Whether the B/C would actually exceed 1.0 is a class project for my transportation economics class this Fall.

Nevertheless, not all forecasts are high. In the Twin Cities, our study "Post-Construction Evaluation of Traffic Forecast Accuracy" show they tended to underestimate traffic.

Article in NYT: Running Out of Money, Cities Are Debating the Privatization of Public Infrastructure

"Reeling from more exotic investments that imploded during the credit crisis, Kohlberg Kravis Roberts, the Carlyle Group, Goldman Sachs, Morgan Stanley and Credit Suisse are among the investors who have amassed an estimated $250 billion war chest — much of it raised in the last two years — to finance a tidal wave of infrastructure projects in the United States and overseas."

This is like what This American Life called "The Giant Pool of Money" which was chasing mortgages a few years ago (and dotcoms before that).

Will we see a similar bubble in infrastructure financing deals gone bad in 5 or 10 years? Was the London Underground Metronet PPP collapse a harbinger of the future?

Unfortunately the ever-growing Giant Pool of Money seeking steady reward does not have foresight, it just finds a short run equilibrium without being able to see the consequences downstream.

Whether these are governed and regulated as public utilities, or unfettered monopolists will make a large difference on their political success as well.

Infrastructure is slow to build and slower to change, it is important to get the investments right. The private sector will want to offload risk and guarantee profit, which is at odds with the public good. The experience with private ownership of infrastructure is mixed, which does not mean it should not be pursued, but that it should be pursued intelligently learning from experience, especially international experience, where private roads, airports, ports, post offices, passenger rail, and transit systems, along with water and sewer, are far more common than in that bastion of market capitalism the United States.

Once upon a time, people kept their life savings on their person or at their homes, stored in physical material like gold and jewelry and property. Then money was invented as a medium of exchange, and people stored a surrogate of their wealth. Then banking was invented, and people centralized their holdings in a bank, and were paid interest for the privilege. Why were they paid? Because the banks could reuse their money by lending it out, at an even greater rate of interest. Money is fungible. I do not lose anything by storing it at the bank (and allowing them to lend it) except the privacy of keeping secret how much money I have, and risk that the bank will be unable to pay me back. The first is resolved through regulations, and the use of multiple banks, the latter by insurance. In any case, it is much safer than storing the money in a mattress at home.

Once upon a time, people kept their life's information on their person or on computers at their home or work, stored in physical material like floppy disk drives, hard disk drives, solid state drives, CDs, DVDs, and USB chips. Then the internet was invented, and centralized servers were made inexpensively and redundantly, and people could store their information in the "cloud". In many cases the cloud is free, or charges only a small fee. In exchange, the recipients agree to allow their personal information to be used to generate customized advertising targeted at them personally. But imagine their were a way for the cloud to earn interest on information much the same way banks earn interest on money, by synthesizing it and "lending it out". Since information is not rivalrous, this may prove viable with sufficient artificial intelligence aimed at developing ontologies and computer intelligence. The risk is the loss of privacy. Alternatively the customer pays the cloud for storage and computation, retaining privacy, in exchange being relieved of duties of backup, which when neglected lead to all too much data loss.

Once upon a time people kept their personal transportation near their person, parking cars and bikes at their homes, workplaces, or other destinations. This was the only way to guarantee point to point transportation in a timely way where densities were low, incomes high, and taxis scarce. Then "cloud commuting" was invented, cars from a giant pool operated by organizations in the cloud would dispatch a vehicle that drives to the customer on demand and in short order, and then deliver the customer to the destination. The vehicle would have the customers preferences pre-loaded (seat position, computing ability, audio environment). The customer benefits of course by not tying up capital in vehicles, nor having to worry about maintaining or fueling vehicles. The fleet is used more efficiently, each vehicle would operate 2 times or 3 times or more miles per year than current vehicles, so the fleet would turnover faster and be more modern. Fewer vehicles overall would be needed. It is likely customers would need to pay for this service (either as a subscription or a per-use basis), there is no obvious analogue to financial interest payments (and while advertising might offset some costs, surely it would not cover them). However stores might subsidize transportation, as might employers, as benefits for the customers or staff.

The tension between centralization and decentralization has been continuous through the history of technology, each has its advantages and disadvantages (and strangely, each also has religious zealots convinced there is one true way). This is ultimately a question of costs and benefits, and who bears the costs and benefits.

I am skeptical that cloud commuting can be made to work quite yet, there are still a few more technologies to perfect. Having tested Zipcar, their system lacks in several ways, much the ways the first banks failed frequently. Zipcars are still not local enough, they charge too much for lateness, the technology is still imperfect. But imagine we have cars that drive themselves. (and to PRT-advocates, these will be cars driving on streets, there are not enough resources to build a new infrastructure network for specialized vehicles). Smart cars solve the localness problem, since the cars come to you. In a way it also solves the lateness problem, because there is no need to reserve a specific car for a specific window, any unused fleet car can be dispatched. There would need to load balancing features, and maybe coordinated carpooling at peak times. (It also saves on parking, especially parking in high value areas).

Related links:

* Technological change, part 2: Autonomous vehicles

* The Future of Cars

From the Strib (and an email to U of M people yesterday) Safety concerns prompt traffic limits on U bridge

Bikes and Peds will be limited to the center of the upper deck of the Washington Avenue bridge. If the pedestrian weight is a real consideration (as opposed to say, falling off the side, or the need to do reconstruction), that makes me real nervous. The vibration from the trucks and buses below on the lower deck must do more damage than a few dozen pedestrians on the upper deck of the bridge.

It's not like the Golden Gate bridge, where on the 50th anniversary, the bridge flattened out.

I suspect something was not fully revealed in the article.

From Mind Hacks: Experienced drivers perceive the road differently Experience drivers have more peripheral vision than novice drivers ... and thus are more likely to perceive and anticipate danger and adapt to changing circumstances on the road.

The problem is if we don't let drivers on the road until they are experienced, no one can get experience, unless we have really good simulators the way they do for pilots, or better yet, like in Orson Scott Card's Ender's Game.

"Will it draw hot chicks?" is the opening line from the Strib article (via Greater Greater Washington) For new rapid bus lines, much is riding on image

The article contains a good discussion of branding BRT vs. LRT, and the "attractive young female" factor. The key of course is investing enough in buses that people (attractive and ugly, female and male, young and old) have some confidence in the system, like for instance, knowing which buses stop (and when, and where they are going, and how much it costs) at a bus stop (still a mystery in the Twin Cities if you don't have a printed schedule with you or internet access).

No one will try transit without some introductory information. Bus stops are ideal places to provide that information, but the transit agency does not prioritize this. The example of London's buses should be reviewed.

Continuing on the game of rankings: US News has posted its rankings, Minnesota schools are here: Minnesota college rankings

It shows, among national universities, The U ranks 61, but 22 among public universities.

This is considerably worse than Academic Ranking of World Universities posted yesterday which placed us 28th in the world (though arguably 7th among North American university systems).

It is however much better than than this news: University ranked 524th by Forbes.

I wonder if these guys really have a methodology, or just a roulette wheel.

As part of our Simulating Transportation for Realistic Engineering Education and Training NSF project, we have been assembling an active textbook. The book, Fundamentals of Transportation , is part of the wikibooks project, and aims to provide pages that provide an introductory and fundamental look at transportation, targeted at the undergraduate Introduction to Transportation course.

As a wikibook, it is editable by anyone, however unlike wikipedia, we aim to keep the contributors known. If you have additions, corrections, and improvements to make, please do so, but please use your real name so we know who you are (at least on your user page) (or email me identifying yourself if you really need to be web anonymous. Additional resources, good diagrams, better explanations, problem sets, etc. are welcome. All need to meet the wikibook standard of being licensable under the GNU Free Documentation License. Anything you create and are willing to license is fine, as is public domain. Copyrighted material is not, without permission of copyright holders.

From a quality perspective, this book needs to be appropriate for an undergraduate textbook, so the difficulty level should be tuned to that. Of course, it also needs to be correct or true to the best of our knowledge.

Comments are welcome.

The most recent Academic Ranking of World Universities is now out

The University of Minnesota ranks 28th in the World, 21st in the North American region, and 10th among US public universities (which can be compared with the oft-stated goal to be among the top 3).

Minnesota is behind UC Berkeley, UCLA, UCSD, Penn, Washington, Madison, UCSF, Michigan, and Illinois. Given four are really part of the UC system (and UCSF was once part of UC Berkeley), we can describe ourselves as the 7th best public university system in US.

These rankings try to apply a systematic way to compare what is largely subjective. What would be useful would be looking at who produces the most Ph.D.s that go on to teaching at universities that produce Ph.Ds, etc., analogous to Google PageRank.

From Megan McArdle,: auctioning landing slots

"Landing slots are a scarce public resource that are being overused because they're underpriced. "

This of course is true. Interestingly enough though, even airports with a monopoly airline (like say NWA at MSP) still have congestion problems, even though congestion is nominally internalized within the airline. In part this is because the delay is suffered by passengers as much as the airline itself (while airlines must pay more for fuel and salaries, the value of time of 150 passengers is pretty high, and not fully considered, especially when there is no competition).

An interesting series of papers by Joseph Daniel discusses this.

including:

Daniel, Joseph I. Distributional Consequences of Pricing(1998). University of Delaware Economics WP No. 98-03.
Available at SSRN: http://papers.ssrn.com/sol3/papers.cfm?abstract_id=106668

Daniel, Joseph I. and Pahwa, Munish, Comparison of Three Empirical Models of Pricing(1998). University of Delaware Economics WP No. 98-01.
Available at SSRN: http://ssrn.com/abstract=106648

Review of Traffic: Why We Drive the Way We Do (and What It Says About Us) by Tom Vanderbilt. Published by Knopf (2008). ISBN 978-0307264787

Traffic by Tom Vanderbilt is a new book (out in July 2008) that provides an exceptionally well-written and comprehensive survey of the more interesting questions in driver psychology, traffic engineering, human behavior and to a lesser extent transportation planning. Following in a line of non-fiction books like those by Malcolm Gladwell and Steven Johnson, it takes an idea and develops it thoroughly (with 96 pages of footnotes and references). It posits road travel as a microcosm of human relations that not only can be informed by an understanding of experimental and behavioral economics, but whose findings can be exported to help us understand the workings of society.

The key questions Vanderbilt examines range from when to merge at a highway lane drop, why the other lane seems faster, drivers increasing (and unwarranted) self-esteem, misperception of risks and traffic safety, why slower can sometimes be faster and the ideas behind shared space, changing travel behavior patterns and increased female labor force participation, to questions of induced demand and travel time budgets.

When exploring these topics, Vanderbilt discusses key evidence and findings, citing the work of relevant scholars or practitioners, so this is true reporting and synthesis, rather than advocacy or agenda-pushing that one fears with more popular books, especially popular books in transportation and planning where everyone is an expert).

When interpreting the literature in a finite amount of space and time, there will always be omissions or simplifications or misinterpretations. As such I have a few nits to pick.

p. 121 "The ideal highway will move the most cars, most efficiently at a speed just about halfway [between 80 and 20 mph]." The book is referring obliquely to the Greenshields model of the Fundamental Diagram of Traffic. Most of the recent evidence suggests that maximum flow can be achieved at about freeflow speed, i.e. the fundamental diagram is a truncated triangle rather than a parabola for a single road segment. The issue is more complicated for a network which has spillovers from downstream links, where the combination of segments produces a more parabolic shape.

p. 158 The explanation of Braess's Paradox could really have been aided by a graphic (and an equation, at least in the notes). I know this is for a general audience, but the book totally lacks in what would be very helpful illustrations of some of the key concepts. It would also have been aided by an introduction of Wardrop's Equilibrium and System Optimal principles. One suspects it was cut, as there is an allusion to the topic, and Wardrop is mentioned in the notes. On the same page, Roughgarden is mentioned, but not his poetic "Price of Anarchy", which is also really interesting in this context (the loss to letting drivers navigate themselves is much less than one might think). This would also have tied really well into the subsequent discussion of road pricing, which aims to internalize the congestion externality so that system optimal and user equilibrium costs are the same.

Finally, I need to get his agent. The book was on the Amazon Top 20, and currently sits at 49. In a way it is a book that I wish I had written, with a much better title than "Freakoportation" which I had (facetiously) suggested to Kara Kockelman of the University of Texas.

Nevertheless, I eagerly await Traffic 2, or whatever Vanderbilt's next project turns out to be. There is so much more in the field of transportation to cover, and really it is much more difficult and interesting than rocket science.

-- David Levinson
dlevinson@umn.edu

There is move afoot to lower the drinking age from 21 back to 18. I was born in 1967, and thus was always on the window of not being allowed to drink in college at Georgia Tech while my few month older friends always could. As a consequence or nevertheless (well correlation is not causation, so perhaps I should say: in addition), I imbibe not.

Yet the logic for this drinking age always escaped me. The problem it is claimed is that driving and drinking do not mix, neither shaken nor stirred. The solution is obvious, drinking without driving does not kill innocents (generally), driving without drinking still does kill innocents. Let us raise the driving age.

Driving age is more easily regulated (you can't realistically ask an older friend to buy a car for you) and raising it will save more lives, and perhaps discourage binge drinking.

Driving is a privilege, and should be treated as such. Some will claim they need cars to get to work or wherever. This may be true for some, given how they have chosen to arrange their lives, yet somehow almost everyone survived without a private car 100 years ago. There is public transport, bicycles, carpooling, taxis, etc. available. I am very dubious about the whole concept of "I need ..." as opposed to "it would be convenient if I ..."

What is the optimal age for driving? I do not know, I would find it improbable the optimal age is 16 (though I did get my own license on my 16th birthday). Given safety rates, it might be as old as 25 for men, though there need to be rational trade-offs between value of time and value of life. Experiments in various states would be interesting to analyze as empirical evidence could help clarify the issue.

An article on the current debate is here:
Opening a Debate Over a Lower Drinking Age

The Fail Blog lists amusing and depressing (and occasionally not safe for work) photos and videos of design failures and Darwin Award winners

I have scraped the site for some of the best transportation related pictures (trying to remove the obvious fakes), and present them here. First up, problems with transportation for the physically disabled, and the lack of a systems perspective on these things.

http://www.darrenbarefoot.com/hall/main.php?g2_itemId=49556

Just like a four-year old TV show with nearly 100 episodes, this blog is now being syndicated to Amazon for my "Plog" (a blogging service for authors to reach people who have (or might) purchase their books). This link shows the Plog previously (which required a manual update, and hence was largely ignored) David Levinson "David M. Levinson"'s Amazon Blog

Now, fresh content should immediately show up on the Amazon pages.

From "The Oil Drum" High-Tech Hitchhiking a proposal to automate what has been called "Casual Carpooling" or "Instant Carpooling", or Slugging. This is an idea the late Mel Webber at Berkeley had in principle, but now it seems the technologies are in place to execute.

One should also see the book Curb Rights to anticipate the problems this might generate.

From AP: Highway crashes kill more than 41,000 in 2007

"By KEN THOMAS, Associated Press Writer
Thu Aug 14, 11:26 AM ET
WASHINGTON - Traffic deaths in the United States declined last year, reaching the lowest level in more than a decade.

Some 41,059 people were killed in highway crashes, down by more than 1,000 from 2006.

The fatality rate of 1.37 deaths for every 100 million miles traveled in 2007 was the lowest on record, the National Highway Traffic Safety Administration said in its report Thursday.

California had the largest decline, 266 fewer fatalities than the previous year. The largest percentage decreases were in South Dakota and Vermont.

North Carolina's death toll increased the most in the nation, up 121 over the previous year. The District of Columbia and Alaska had the highest percentage increases.

Motorcycle deaths increased for the 10th straight year. There were 5,154 motorcycle deaths last year, compared with 4,837 in 2006."

One wonders what's going on in North Carolina.

From McClatchy (again via Boing Boing) Cop cameras don't just catch speeders, they raise cash

There should be an equilibrium between level of enforcement (both frequency/coverage of enforcement and the associated fines) and maximum revenue, just as between level of enforcement and maximum safety. These two equilibria however are likely not equal. Formulating this model would make a good Ph.D. written exam question.

From (1933) (via Boing Boing) ROBOT GUIDES SUBWAY RIDER IN LONDON

A pre-computer machine to help underground patrons find their destination.

From Oregonian ... Wind whips up health fears

In the category of "the leading cause of death is life", it seems some are saying windmills will make you ill.

Whether or not this is scientifically correct (which I think remains to be convincingly demonstrated, the sample sizes in the newspaper article looked awfully small), one suspects windmill operators will have to buy out neighboring land owners to deal with this noise externality (as airports do today), driving up the price of "clean" wind power.

A nice article in Strib by Bill McAuliffe: Truckers ask other drivers to take go-slower approach (I am quoted on page 3.)

Some freight companies are having drivers slow down, but is the right economic decision for truckers the same as for passengers. Sure slowing down may save fuel, but it costs time, and time is still more precious than fuel.

Via Slashdot from "The Future of Things"Cars that Talk. Europe has reserved spectrum space for vehicle-infrastructure communication systems. Hopefully the same standard is adopted globally so I can drive my Subaru to France.

Seriously, I think the best use would be for cars to broadcast locally their ID, position, velocity, and acceleration so that other cars will know the position of neighbors accurately. This will greatly help automated vehicles maneuver on roads. Smart autonomous cars would be able to operate in mixed traffic. (Clearly they would need ways of detecting vehicles that were not broadcasting as well, but if all nearby vehicles could be located, it would help a lot).

From the Wall Street Journal U.S. Driving Continues to Decrease

"Rural travel has fallen 4% since late last year, while urban driving is off just 1.2%"

A fabulous post (and good comment section) from Megan McArdle: The Pennsylvania Department of Transportation: Sheer genius
regarding her trying to get a driver's license and being held up for a suspended license for underage drinking before she had a license.

The really interesting thing is that underage drinking is against the law in the US primarily because we are concerned about drunk driving (drink driving to those from the UK). She did not have a license then, they just waited for her to apply for one before assessing the suspension, 16 years later, long after she ceased to be underage.

Founder of Hotmail proposes a new town in India, article from SFGate: S.F. tech mogul wants to build city in India How to build a city sustainably

From the Columbia Flier, Emad Elshafei, now a Columbia, MD resident, who earned a Ph.D. at the University of Maryland sometime in the 1990s (after I was there I guess), and is now head of transportation and public works for the City of Rockville, competed in the 1984 Olympics for Egypt.

Any others?

Tom Vanderbilt's Blog mentioned our recent I-35W study ... How We Drive, the Blog of Tom Vanderbilt’s Traffic � Blog Archive � 50,000 Missing Trips

He was just in town, promoting his book (which I have yet to receive or read) and on MPR recently, links below:

MPR: Driver's education (link to interview)

MPR: News Cut: Live-blogging Midmorning: What traffic says about us

From NYT The TierneyLab Traffic Quiz promoting Tom Vanderbilt's new book (I need to get his agent).

TierneyLab Traffic Quiz

From Autopia: Lotus Makes Hybrids Sound Like Real Cars

Apparently some people are worried that quiet cars will not give auditory clues about their presence, and will run over pedestrians (esp. blind pedestrians). So Lotus is developing a technology that will cause the car to make noise even if it is not running on a conventional engine.

From the University of Minnesota's News Service, the list of my recent media coverage all in one convenient place ...

Traffic Patterns After the Collapse
Dr. David Levinson, a University of Minnesota researcher for the Center for Transportation Studies, discussed how the metro roadway system handled the loss of the 35W bridge, and what will happen to traffic in the Cities when the bridge reopens.
Twin Cities Live
To view: http://twincitieslive.com/article/day/S20080801.shtml?cat=10699

Our bridges: To do nothing will cost more
It was a year ago today that the 35W bridge collapsed into the Mississippi River in Minneapolis, stunning a nation that had long taken its vaunted highway system for granted. ... Many observers think an increased use of tolling and congestion pricing could also provide major funding and more efficient utilization, by requiring drivers to pay top dollar during peak times, said David Levinson of the University of Minnesota's civil engineering department.
Star Tribune
http://www.startribune.com/politics/state/26160819.html?page=3&c=y

Drivers adapt to life without 35W bridge
A new study by the University of Minnesota shows that most drivers were able to adapt to detours within two months after the Interstate 35W bridge collapsed last August. ... David Levinson, a professor in the university's Department of Civil Engineering and Center for Transportation Studies, looked at the traffic patterns.
Minnesota Public Radio
To listen: http://minnesota.publicradio.org/display/web/2008/07/30/35w_bridge_detours/

U of M research on 35W collapse
University of Minnesota researchers have found that most drivers have experienced commute times after the 35W bridge collapse that were similar to their times prior to it.
KARE - TV
To view: http://www.criticalmention.com/ctv3-1/landing_email.php?type=email&video=true
&random_string=67342e94ebc4eb481fe39f14482ae1d

7-31 The Don Shelby Show
Thursday, Don found out about how traffic patterns have changed since the collapse of the 35W Bridge.
To hear: http://blog.lib.umn.edu/levin031/transportationist/LevinsonOnShelby.mp3

No clip available:

WCCO – Radio: Mondale and Jones Show

From the Guardian: London still gridlocked despite congestion charge

Apparently, the problem is not that the congestion charge reduced demand (trips entering are lower), but that supply has been contracted due to road works and pedestrianization schemes.

Again of course, the objective in a dense city center should not be to move cars faster through the center, it should be about moving people to their destinations in the least time, and giving them more possible destinations.

Also the term "gridlocked" is used quite loosely and hyperbolically here.

Our research group has released a slew of working papers this week: Working Papers - Nexus: Researching Networks, Economics & Urban Systems

These are listed below

• Liao, Chen-Fu, Henry Liu, and David Levinson (2008) Engaging Undergraduate Students in Transportation Studies through Simulating Transportation for Realistic Engineering Education and Training (STREET)

  The practice of transportation engineering and planning has evolved substantially over the past several decades. A new paradigm for transportation engineering education is required to better engage students and deliver knowledge. Simulation tools have been used by transportation professionals to evaluate and analyze the potential impact of design or control strategy changes. Conveying complex transportation concepts can be effectively achieved by exploring them through simulation. Simulation is particularly valuable in transportation education because most transportation policies and strategies in the real world take years to implement with a prohibitively high cost. Transportation simulation allows learners to apply different control strategies in a risk-free environment and to expose themselves to transportation engineering methodologies that are currently in practice. Despite the advantages, simulation, however, has not been widely adopted in the education of transportation engineering. Using simulation in undergraduate transportation courses is sporadic and reported efforts have been focused on the upper-level technical elective courses. A suite of web-based simulation modules was developed and incorporated in the undergraduate transportation courses at University of Minnesota. The STREET (Simulating Transportation for Realistic Engineering Education and Training) research project was recently awarded by NSF (National Science Foundation) to develop web-based simulation modules to improve instruction in transportation engineering courses and evaluate their effectiveness. Our ultimate goal is to become the epicenter for developing simulation-based teaching materials, an active textbook, which offers an interactive learning environment to undergraduate students. With the hand-on nature of simulation, we hope to improve student understanding of critical concepts in transportation engineering and student motivation toward transportation engineering, and improve student retention in the field. We also would like to disseminate the results and teaching materials to other colleges to integrate the simulation modules in their curricula.

  
  
  Keywords: Transportation Education and Training, Transportation Simulation, Roadway Geometry Design
  
  (working paper).







• Tilahun, Nebiyou and David Levinson (2008) Home Relocation and the Journey to Work

  Relocation decisions are complex. Each household has a bundle of attributes that make a location attractive to it, including the ability to access different activity locations easily, neighborhood quality, house amenities etc. Relocating households have an opportunity to �nd housing closer to their work. Using data collected in the Twin Cities area, we investigate how distance to home and travel time to home change among individuals who have changed their residence since they started their current job. Comparing the home-to-work distance after the move to the previous-home-to-work distance, we �nd that the average home to work distance is reduced as a result of the move. We also �nd that the reduction depend on the previous home to work distance as well as the previous homes’ proximity to downtown Minneapolis. The �ndings show that households that are either very close to their work, or very close to downtown, or both did not signi�cantly increase or decrease their commute after relocation. This suggests that access to work as well as access to the opportunities that proximity to downtown offers (to jobs, urban spaces, etc.) are important in the decision making process.

  
  
  Keywords: Commuting, Location, Journey-to-Work, Tenure
  
  (working paper).







• Iacono, Michael and David Levinson (2008) Predicting Land Use Change: How Much Does Transportation Matter?

  In this paper, we propose to measure the extent of the influence of transportation systems on land use change. Using a set of high-resolution land use data for the Twin Cities metropolitan region, we estimate logistic regression models of land use change covering a 10-year period from 1990 to 2000. The models account for existing land use types, neighboring land uses, and transportation network variables that measure the physical proximity of highway networks, as well as the level of accessibility associated with a speci�c location. The models are estimated with and without the transportation variables and compared to assess the extent of their influence. We �nd (perhaps not surprisingly) that transportation-related variables exert some influence on changes to land use patterns, though not as much as variables representing existing and neighboring land uses.
  

  
  
  Keywords: Land use, Twin Cities (Minnesota), Mathematical models, urban growth
  
  (working paper).
  








• Iacono, Michael and David Levinson (2008) Review of Methods for Estimating the Economic Impact of Transportation Improvements

  Transportation analysts and the public decision-makers they support are confronted with a broad range of analytical tools for estimating the economic impacts of improvements to transportation networks. Many of the available models operate at different scales and have distinctly different structures, making them more or less appropriate for analyzing the impacts of different types of projects. Here, we review several of the economic methods and models that have been developed for analyzing the impact of transportation improvements, giving special attention to types of projects that add highway capacity in urban areas. We review project-based methods, including bene�t-cost analysis and several analytical software tools developed by the Federal Highway Administration (FHWA) for economic analysis of transportation investment.
  We then move on to aggregate and disaggregate-level econometric methods, including regional economic models, hedonic price functions, production functions and cliometric analyses. We also devote some attention to the role of induced demand in economic evaluation, since it is often one of the most uncertain and confounding factors faced by those charged with conducting economic evaluation of transportation projects.
  

  
  
  Keywords: Economic Impact, Benefit-Cost Analysis, Literature Review
  
  (working paper).
  







• Zhu, Shanjiang and David Levinson (2008) A Review of Research on Planned and Unplanned Disruptions to Transportation Networks

  Travel decisions may be very stable in an environment with which they are familiar. Ma jor network disruptions such as the I-35W bridge collapse disrupt habitual behavior. Such "natural" experiments provide unique opportunities for behavioral studies, but the time window for such studies is limited. A well-developed methodology is crucial for both data collection and analysis, and thus the soundness of behavioral models , especially in such a limited time window. Therefore, this paper reviews both theoretical and empirical studies on traffic and behavioral impacts of network disruptions. Findings from this paper offer prospective ideas about capturing the impacts of network disruption.

  
  
  Keywords: Network disruption; Travel survey; Travel behavior
  
  (working paper).
  







• Parthasarathi, Pavithra and David Levinson (2008) Post-Construction Evaluation of Trafï¬?c Forecast Accuracy

  This research evaluates the accuracy of demand forecasts using a sample of recently-completed projects in Minnesota and identi�es the factors influencing the inaccuracy in forecasts. The forecast traf�c data for this study is drawn from Environmental Impact Statements (EIS), Transportation Analysis Reports (TAR) and other forecast reports produced by the Minnesota Department of Transportation (Mn/DOT) with a horizon forecast year of 2010 or earlier. The actual traf�c data
  is compiled from the database of traf�c counts maintained by the Of�ce of Traf�c Forecasting and Analysis section at Mn/DOT. Based on recent research on forecast accuracy, the (in)accuracy of traf�c forecasts is estimated as a ratio of the forecast traf�c to the actual traf�c. The estimation of forecast (in)accuracy also involves a comparison of the socioeconomic and demographic assumptions, the assumed networks to the actual in-place networks and other travel behavior assumptions that went into generating the
  traf�c forecasts against actual conditions. The analysis indicates a general trend of underestimation in roadway traf�c forecasts with factors such as highway type, functional classi�cation, direction playing an influencing role. Roadways with higher volumes and higher functional classi�cations such as freeways are subject to underestimation compared to lower volume roadways/functional classi�cations. The comparison
  of demographic forecasts shows a trend of overestimation while the comparison of travel behavior characteristics indicates a lack of incorporation of fundamental shifts and societal changes.

  
  
  Keywords: Traffic Forecast, Travel Demand Model, Transportation Planning
  
  (working paper).
  







• Huang, Arthur and David Levinson (2008) The Effects of Daylight Saving Time on Vehicle Crashes in Minnesota

  Daylight saving time (DST), implemented as an energy saving policy, impacts many other aspects of life; one is road safety. Based on ten-year vehicle crash data in Minnesota, this paper evaluates long- and short-term effects of DST on daily vehicle crashes, as well as daily fatal crashes. Our statistical models not only include weather conditions and days of week as independent variables, but also consider traf�c volume count on road. Our �ndings show that DST, in the long run, is associated with fewer daily crashes than standard time (ST). Yet, DST is found to be associated with higher odds of having more fatal crashes than ST. In addition, our data rejects the hypothesis that the �rst Sunday or Monday of time change in spring is associated with more fatigue-related crashes than Sundays before time change; nor do we �nd that the �rst Sunday or Monday of time change in fall is associated with more alcohol-related crashes than Sundays before time change. Of all weather conditions, snow is found to have the most signi�cant effect on vehicle crashes; however, its impact on fatal crashes is nevertheless not statistically different from clear weather. Furthermore, Friday is associated with the most daily crashes, whereas Sunday and Saturday are associated with higher odds of more fatal crashes than weekdays.

  
  
  Keywords: daylight saving time, vehicle crashes, fatal crashes, traf�c volume
  
  (working paper).
  











• Huang, Arthur and David Levinson (2008) An Agent-based Retail Location Model on a Supply Chain Network

  Clusters of business locations, which considerably impact daily activities, have been prominent phenomena. Yet the question of how and why �rms cluster in certain areas has not been suf�ciently studied. This paper investigates the emergence of clusters of business locations on a supply chain network comprised of suppliers, retailers, and, consumers. Krugman (1996) argued that urban concentration involved a tension between the “centripetal� and the “centrifugal� forces. Based on that notion, this research proposes an agent-based model of retailers’ location choice in a market of homogeneous products. In this game, retailers endeavor to maximize their pro�ts by changing locations. Retailers’ distribution patterns are measured by entropy and cluster density. Simulation results reveal that as more retailers engage in the game, clusters autonomously emerge and the entropy of clusters increases. Once retailers exceed a certain number, average density of clusters begins to decline; all discrete clusters gradually merge to a large cluster, spreading out uniformly. This research thus �nds that the centripetal
  force attracts retailers to supplier locations; with even more retailers entering the market, the centrifugal force disperses them. The sensitivity results on model parameters and consumers’ demand elasticity are also discussed.

  
  
  Keywords: clustering, supply chain network, location choice, distribution pattern
  
  (working paper).
  







• Geroliminis, Nikolas and David Levinson (2008) Cordon Pricing Consistent with the Physics of Overcrowding

  This paper describes the modeling of recurring congestion in a network. It is shown that the standard economic models of marginal cost cannot describe precisely traffic congestion in networks during time-dependent conditions. Following a macroscopic traffic approach, we describe the equilibrium solution for a congested network in the no-toll case. A dynamic model of cordon-based congestion pricing (such as for the morning commute) for networks is developed consistent with the physics of traffic. The paper combines Vickrey’s theory with a macroscopic traffic model, which is readily observable with existing monitoring technologies. The paper also examines some policy implications of the cordon-based pricing to treat equity and reliability issues, i.e. in what mobility level a city should choose to operate. An application of the model in a downtown area shows that these schemes can improve mobility and relieve congestion in cities.

  
  
  Keywords: congestion pricing, traffic models, macroscopic fundamental diagram
  
  (working paper).
  











• Wu, Xinkai, David Levinson, and Henry Liu (2008) Perception of Waiting Time at Signalized Intersections

  Perceived waiting time at signalized intersections differs from the real value, and varies with signal design. The onerousness of delay depends on the conditions under which it is experienced. Using weighted travel time time may contribute to optimal signal control if its use can improve upon assuming that all time is weighted equally by users. This research explores the perception of waiting time at signalized intersections based on the results of an online survey, which directly collected the perceived waiting time and the user ratings of the signal designs of each intersection on an arterial including 3 intersections. Statistically analyzing the survey data suggests the perception of waiting time is a function of the real time; and a quadratic model better can describes relationship. The survey also indicates that there exists a tradeoff between the total waiting time and the individual waiting time of each intersection. It turns out that drivers prefer to split the total waiting time at different intersections at the price of a longer total wait if the difference of the total waiting time of two signal designs is within 30 seconds. The survey data shows that the perceived waiting time, instead of the real waiting time, better explains how users will rate the individual signal designs for both intersections and arterials including multiple intersections.
  

  
  
  Keywords: delay, perceived time, traffic signals
  
  (working paper).
  







• Zhu, Shanjiang, David Levinson, Henry Liu, and Kathleen Harder (2008) The Traffic and Behavioral Effects of the I-35W Mississippi River Bridge collapse

  The collapse, on August 1, 2007, of the I-35W bridge over the Mississippi River in Minneapolis, abruptly interrupted the usual route of about 140,000 daily vehicle trips and substantially disturbed the flow pattern on the network. It took several weeks for the network to re-equilibrate, during which period, travelers continued to learn and adjust their travel decisions. A good understanding of this process is crucial for traffic management and designing mitigation schemes. A survey collected behavioral responses to the bridge collapse. Traffic data were also collected to understand the traffic conditions experienced by road users. Data from both resources are analyzed and compared. Findings of behavioral effects of capacity changes could have signi�cant implications for travel demand modeling, especially of day-to-day travel demand.

  
  
  Keywords: I-35W bridge collapse, travel behavior, travel survey
  
  (working paper).

  
  







• Xie, Feng and David Levinson (2008) How Streetcars Shaped Suburbanization: A Granger-Casality Analysis of Land Use and Transit in The Twin Cities

  This paper presents a causality analysis of the coupled development of population and streetcars in the Twin Cities metropolitan area. Historic residence and network
  data were assembled for 1900-1930, and linear cross-sectional time-series models were estimated at both a tract and block level using this data. It is found that, in contrast with transportation systems that were expanded in response to increased demand, the rapid expansion of the streetcar system during the electric era has been driven by other forces and to a large extent led land development in the Twin Cities. The main forces that have driven this process include technological superiority, monopoly, close connections with real estate business, and people’s reliance on the streetcar for mobility. Proximity to the streetcar is found to be a crucial factor that determines the distribution and development of residences: it is observed that residential density declines with the distance from streetcar lines, and signi�cantly drops beyond a walkable distance; it is also observed that gaining a closer access to streetcar lines within 800 meters (about a half mile) predicts the increase in residential density to a signi�cant extent.

  
  Keywords: streetcars, light rail transit, land use and transportation, development, Twin Cities (Minnesota), network growth
  
  (working paper).
  











• Xie, Feng and David Levinson (2008) Evaluating the Effects of I-35W Bridge Collapse on Road-Users in the Twin Cities Metropolitan Region

  This study evaluates the effects of I-35W bridge collapse on road-users in the Twin- Cities metropolitan area. We adopted the Twin-Cities (Metropolitan Minneapolis
  and St. Paul) Seven-County travel demand model developed in previous research, recalibrated it against July 2007 loop detector traffic data, and used this model to carry out an evaluation of economic loss incurred by increased travel delay in alternative scenarios before and after the bridge collapse. We concluded that the failure of the I-35W bridge resulted in an economic loss of $71,000 to $220,000 a day, depending on how flexible road-users in the system can adjust their trip destinations in response to the bridge closing. We also estimated that the ma jor traffic restoration projects Mn/DOT has implemented in quick response to the bridge collapse can save road-users $9,500 to $17,500 a day. This translates into a bene�t-cost ratio of 2.0-9.0, suggesting these pro jects are highly bene�ciary in an economic sense. In this analysis, the use of a simpli�ed, scaled-down travel demand model enabled us to carry out the analysis quickly and accurately, showing its contributions in transportation planning under situations such as emergency relief and comprehensive design.

  
  
  Keywords: I-35W Bridge Collapse, Twin Cities (Minnesota), economic evaluation
  
  (working paper).
  










• Patterson, Tyler and David Levinson (2008) Lexus Lanes or Corolla Lanes? Spatial Use and Equity Patterns on the I-394 MnPASS Lanes

  A 2004-2006 longitudinal panel survey of I-394 residents found support levels at over 60 percent for the congestion priced High Occupancy Toll (HOT) lane, known to the Twin Cities as MnPASS. This number varies only slightly when sorted by income levels, gender, and education levels, suggesting that the arrangement is perceived as equitable.
  However, people with higher incomes use the system more often and thereby capitalize on the direct benefit more often, a finding consistent with other studies. Previous research has not revealed whether higher incomes actually cause people to use the MnPASS option more often or whether HOT lanes have simply been built along high income corridors, such as I-394. This paper aims to separate the effects of income and location on use to provide a more robust understanding of equity concerns. Using data provided by the Minnesota Department of Transportation, Heteroskedasticity-Consistent
  Method 3 (HC3) regressions, this paper suggests that location and income both explain
  HOT lane use.

  
  
  Keywords: Congestion Pricing, HOT Lanes, High Occupancy Toll lanes, Value Pricing, Equity, Twin Cities (Minnesota), economic evaluation
  
  (working paper).
  

According to Politico: GOP hopes to skirt Minn. bridge issue

With an expected opening in Mid-September to Mid-October, it will be interesting to see if the media does avoid re-examining the bridge collapse.

A podcast (mp3) of my interview on WCCO radio discussing the traffic effects of the I-35W Bridge Collapse with Don Shelby is now available: Download file