July 2010 Archives

The Explosions of Every Nuclear Bomb to 1998

The Explosions of Every Nuclear Bomb to 1998 This video, by artist Isao Hashimoto, charts every nuclear detonation from the US's tests in 1945 to the modern era. Even if you're versed in history, it still offers a perspective that's tough to entirely grasp in numbers alone. The pacing, mixed with an Atari-esque soundtrack is both distancing and hypnotic. As more and more countries gain nuclear technologies, the map becomes a terrifying game of Simon. By the end, it feels remarkable that we never encountered a game over...as of yet.

(Via Gizmodo .)

From the Strib: Are downtown two-way streets better?

"On Tuesday, the brass at Minneapolis City Hall declared last fall's conversion of Hennepin and 1st Avenues back to two-way traffic a success.

Crashes are down for both motor vehicles and bikes, despite a slight increase in volume, and the number of traffic-clogged intersections is down. But out on the avenues, opinion is decidedly more mixed."

It seems people feel less safe. What they don't recognize is that feeling less safe may make them more safe if they are then more cautious. Bike traffic is down on Hennepin, but up overall on parallel routes.

Net Density was not happy with the design, and I don't think this is fully resolved despite installation of seemingly temporary and not attractive bollards/delineators .

I think the problem is they are doing this on the cheap. I am all for inexpensive, but a bit more investment in paint/pavement coloring would help. A slightly more serious attempt could much more clearly delineate which people/vehicles are supposed to be where, with somewhat less confusion. The signs don't help, probably because the regulations are too complex about lane usage.

USA Today profiles Minneapolis Cities tackle traffic head-on with commuter options finally published. I get quoted briefly at the bottom. Also misquoted, I was talking about mode share on all trips, the article says work trips.

For the record, Brookings estimates Minneapolis-St Paul-Bloomington Transit mode share at 4.8% in 2008, nationally transit commuters are about 5.0% of all commuters.

Non-work transit mode share is much lower. Overall,

Transit Person Miles Traveled nationally is about 1% of Annual Private Vehicle Person Miles Traveled (source: Polzin and Chu: A Closer Look at Public Transportation Mode Share Trends. Journal of Transportation and Statistics 8(3)) Trip shares are a bit higher for transit since trip length for most bus trips is lower than private car.

The Twin Cities TBI (2000) estimated for all purposes transit mode share of 2.5%.

I think this could be fixed by deleting "work" from "work trips" in the ante-penultimate paragraph.

And now for something different: 3-D Pavement Art: Edgar Mueller - Ice Age/The Crevasse

"Edgar Müller - a Master of 3d Pavement Art - needed 5 days to the completion of this huge picture. Together with up to five assistant he painted all day long from sun rise to set. The enormous illusion is reached by applying the anamorphic technique to a huge pavement painting. Around 250 square meter large this picture is part of Edgar's newest project. He paints over urban areas to give them a different look and thereby challenge the audience's perception."

The International Symposium on Transportation Network Reliability is now on a semi-quinquennial cycle: the next (5th) will be in December 2012 in Hong Kong. This will be followed by the 6th meeting in Summer of 2015 in Japan. INSTR is thus the first conference series (to our knowledge) to meet on a cycle of four meetings per decade.

As host of the 4th INSTR, I want to extend my thanks to the following for making it work smoothly:

(1) The Center for Transportation Studies for donating the time and effort of Stephanie Malinoff through the long preparation period and Stephanie and Liz Erickson on the conference days. Also to Arlene Mathison for coordinating the website.

(2) College of Continuing Education for coordinating the logistics, in particular Catherine Flannery, Kristi Fischer, Nicole Freese, Tonya Walsh, and Sara Van Essendelft

(3) Brian Kary of MnDOT for giving the opening plenary talk

(4) Taylor and Francis for sponsorship

(5) Bill Hyman for helping distribute the announcement and encouraging attendance among those in the SHRP program

(6) Peer reviewers for taking the time to review the papers

(7) My colleague Henry Liu for co-hosting and helping with organization, and with ground transportation, with his student Sean He and post-doc Xiaolei Guo

(8) Restaurant facilities (Tea House and Campus Club) and the caterers for handling everything smoothly, as well as the Hotels (Days and Ramada), as well as the facilities at Coffman.

(9) Authors and participants for attending.

I hope to see everyone in Hong Kong.

From Grush Hour Tolling Scofflaws - 1859

Canadians have a venerable history of disdain for road tolls, so that the spoiled and entitled commenters that whine and threaten at the end of every Toronto newspaper article about tolling are hardly equipped with novel thoughts. Here are a couple of Krieghoffs from 150 years ago. According to the Art Gallery of Ontario (AGO), Cornelius Krieghoff apparently came down on the side of the scofflaws and perhaps admired them.

CNN: Bear gets stuck in car, goes on brief ride

On The Path To Pike's Peak: New Video of Stanford's Robot Car

It will be one of the more daring feats of robotic driving ever attempted: Stanford's autonomous car, an Audi named Shelley, will race up Pike's Peak at breakneck speeds. T

The Center for Automotive Research at Stanford (CARS) is also working with Volkswagen to produce a self-parking car.

From FT (h/t Marginal Revolution), an interesting article, Why we still love board games

In Germany, serious board gaming is cool. Many of these games have a transportation or spatial economic theme (e.g. Ticket to Ride or Settlers of Catan).

The Fourth triennial INternational Symposium on Transportation network Reliability (INSTR) starts tomorrow morning at the University of Minnesota campus in Minneapolis. We have a pre-conference dinner tonight at Tea House. The symposium program is available at the website. We look forward to seeing everyone.

AP reports: Italy to China in driverless vehicles

A team of Italian engineers on Tuesday launched what has been billed as the longest-ever test drive of driverless vehicles: a 13,000-kilometer (8,000-mile), three-month road trip from Italy to China, not in search of silk, but to test the limits of future automotive technology.

BBC News: How super? What cyclists make of superhighways BoJo is installing 'bicycle superhighways' in London (well marked bike lanes, not quite superhighways). The naming rates for the network have been sold to. Barclays Bank

My colleague José Holguin-Veras at RPI recently completed a study on scheduling freight deliveries in New York City. The conclusion was not surprising to those in the field, there are gains to be had from scheduling deliveries outside the peak; surprisingly though, this is not done already (analogous to the economist's $10 bill lying in the street, but in this case a $1000/month check going uncollected). This is the result of coordination and principal/agent issues (it costs receivers more to receive off-peak), which information and appropriate pricing and incentives should be able to solve.

From one press release: NYC DOT Pilot Program Finds Economic Savings, Efficiencies For Truck Deliveries Made During Off-hours.

New York City Department of Transportation (NYC DOT) Commissioner Janette Sadik-Khan today announced that a pilot program undertaken with the trucking industry found that trucks making off-hour deliveries between 7 p.m. and 6 a.m. instead of at peak hours experienced fewer delays, easier parking, reduced congestion and significant savings for the 33 participating delivery companies and business locations receiving shipments. The study, the first that engages both delivery companies and businesses, also found that businesses overwhelmingly supported the benefits, with travel speeds improved as much as 75% and a sharp reduction in parking tickets and fines which exceeded $1,000 a month for each truck. Several participants continue to make off-hour deliveries and DOT is now developing ways to build upon this pilot. Joining the Commissioner was U.S. Department of Transportation Research and Innovative Technology Administration (RITA) Administrator Peter Appel at a 14th Street location of Foot Locker, one of the retail participants in the study, as well as representatives from Sysco, Whole Foods Market and New Deal Logistics. ... More information on the Manhattan Off-Hour Deliveries Pilot can be found at http://transp.rpi.edu/~usdotp.

The project's premise is

Receivers, by virtue of being the carriers' customers, have a significant power in setting delivery times and, consequently, trucks' time of travel.

Carriers cannot switch operations to the off-hours, without receivers willing to accept Off-Hour Deliveries (OHD).

In equality of conditions, carriers will prefer to deliver during the off-hours because of the higher productivity and lower costs (even when paying prime wages to the crews).

The carriers' cost savings are not large enough to enable shipping cost discounts large enough to attract receivers to OHD.

From You're the Boss Blog - NYTimes: How I Saved My Company: Mile Meter. A four minute video piece by and about Mile Meter, a new car insurance company that offers Pay-as-you-drive insurance, which is a good thing, since it turns a fixed cost of driving into a variable cost, which more closely approximates the underlying cost structure (if you aren't driving, it is hard to crash your car), and thus better aligns with true full costs of driving (and likely discourages driving as a result - the extent of this would be an interesting study).

The company's website is here: MileMeter. It seems to be available only in Texas.

From the Guardian in the UK: Graduate tax to replace tuition fees for university students . So instead of paying tuition now, graduates would pay a higher tax later to pay back the loan for their education. So they would pay based on economic benefit received (higher income) rather than on the input (cost). Government, rather than students, assumes the risk that education is economically worthwhile. An interesting idea worth following.

Cameron Booth maps Amtrak as a Subway Map. He also has done maps of the US Interstate Highway system similarly. The network structures are very different.

I am scheduled to be on Minnesota Public Radio's Midmorning Thursday July 15 at 9am to talk with Kerri Miller and Tom Vanderbilt about Nimble Cities.

If you have good ideas, call in.

Is existing infrastructure in good shape? [Yes or No]

Should existing infrastructure be in good shape? [Yes or No]

The answers to these questions should dictate an answer to the question of whether infrastructure requires more funding.

The first question is empirical (depending on what standard you apply to "good shape"). E.g., there are an empirical way to assess road quality, one is the roughness index (assessed by running a vehicle with a trailing wheel, the cumulative vertical movement of the trailing wheel per unit distance is a measure of roughness). Clearly some roads are smoother than others. New roads tend to be smoother than older roads. Roads before snow plowing are smoother than roads after snow plowing.

You may believe infrastructure is in good shape, or you may not.

The second question is normative, should infrastructure be in good shape (relative to its existing state). I have seen advocates for non-auto modes of transportation argues that the worse roads are, the more people will switch modes. I have also seen neighborhood activists argue against smooth roads as a way of discouraging traffic (a natural form of traffic calming). Underfunding of buses has been used to support rail transit. Most advocates do not argue this, but there are people who do.

So combining the answers to these two questions we have the following, (with the natural policy prescription regarding funding in parentheses, assuming money is required to maintain or rebuild infrastructure)

(1) Infrastructure is in good shape and should be in good shape (do nothing different)

(2) Infrastructure is in good shape and should be in bad shape (cut funding)

(3) Infrastructure is in bad shape and should be in good shape (raise funding)

(4) Infrastructure is in bad shape and should be in bad shape (do nothing or cut funding).

Given that the number of people who actually believe infrastructure should be in bad shape is small, the main debate is between (1) and (3). Given not many people would say infrastructure is in good shape in most urban areas,(ASCE rates roads a D-, tied for the lowest of all infrastructure, though any reports cards like this are suspect) raising funds for infrastructure, should be as they say, a no-brainer.

So what is the problem?

People do not believe the money will be well-spent or they believe infrastructure will heal itself. I believe we should look into technologies that can do the latter (self-annealing roads would be great), but the more fundamental problem is the lack of confidence about spending.

This distrust is general, but especially emerges when decisions are politicized. Bridges to Nowhere, while a small-part of actual transportation funding, garner most of the attention. Pothole fillers not doing their job get media, those actually filling potholes do not. Because these are public sector investments, they get much more attention than private sector utilities. I am sure some telco employee has loafed at some point in their career, without making the news.

This leads me to the conclusion, the problem with raising funds is the public and political nature of transportation funding (which prior to the latest downturn, I used to call the last bastion of socialism in the US).

Can transportation funding be isolated and depoliticized, like a public utility, where users pay charges that are dedicated (and more importantly are believed to be dedicated) to provide services for the users? Every month, households get a natural gas bill, a water bill, an electric bill, a cable bill, a phone bill. Households may grumble, but they pay the bill. Rates go up periodically as needed, with public oversight for most of these utilities. Where is the road bill?

We have federal and state highway trust funds, supported largely by a tax on gasoline, while local funds tend to come from general revenue sources, all of which no-one in the public understands. But we still have political intervention in decision-making that is highly visible, usually unproductive, biased toward new capital expenditures rather than operations and maintenance, and generally confidence-destroying.

Major facilities still need oversight, just as high-voltage lines or any other infrastructure. But these should be professional decision determined by organizational mission rather than political decisions to help ensure re-election by bringing home bacon.

An independent transportation infrastructure utility (and a separate independent transit services utility) which is governed independently from the legislative and executive branches is needed to enable us to achieve new funds for old infrastructure.

Tom Vanderbilt has curated the Nimble Cities project at Slate.

There are some good ideas (nothing I haven't seen before, unfortunately, though lots that has yet to be implemented). Clearly the voting was gamed by at least some of the participants. ("Humanity's Highway to a Sustainable Society Submitted by George Schrader"). I am pleased to see the Land Value Tax ("eliminate the property tax") getting some love (if not some gamesmanship), as well as ultra-narrow cars. Lots of attention for bicycles (3 of top 10), especially given their current mode share in US cities.

Reallocating roadspace (modally, directionally, by vehicle type, dynamically, etc.) needs far more attention than it gets.

Wikidirections A wiki for directions (for those who prefer not to use GPS or mapping services). Essentially no content yet. Will there ever be?

Google's OpenSpot Find an open parking spot, if someone notifies this service AND it hasn't been taken by someone else before you get there. Ultimately doomed because it cannot be useful unless it is automatic and ubiquitous. (And it won't be ubiquitous unless it is useful).

Since it is now officially out, congratulations to Laurie McGinnis, who is no longer "acting".

Date: July 7, 2010

To: CTS Committee Members

Fr: Robert J. Jones, Senior Vice President for System Academic Administration
Andrew Furco, Associate Vice President for Public Engagement

Re: Appointment of Director for Center for Transportation Studies

We are pleased to inform you that Ms. Laurie McGinnis has been appointed as the new Director of the Center for Transportation Studies (CTS), effective July 5, 2010. This appointment is the result of a comprehensive national search process that included a review of 19 well-qualified applicants from throughout the country.

As Director of CTS, Ms. McGinnis will provide leadership, direction, and vision in achieving the mission of the Center, which includes advancing innovations that put the University at the forefront of transportation research. She will facilitate the work of more than 100 contracts totaling more than $20 million, which engage faculty and other transportation experts in conducting research that addresses some of today's most important transportation issues. Ms. McGinnis will also provide support and leadership to two federally funded programs that operate within CTS: the ITS Institute, a National University Transportation Center (UTC), and the Minnesota Local Technical Assistance Program (Mn LTAP).

Ms. McGinnis has been involved in the transportation field since 1984. Over the last 18 years, she has been a key player in the development and growth of CTS, having served as the Center's Research Coordinator, Director of Research and Contract Management, Associate Director, and Acting Director. Through her previous leadership experiences at CTS she has created new program opportunities that have expanded the Center's national reach, helped streamline operations, and articulated future directions in transportation research, education, and outreach.

Nationally, Ms. McGinnis is active in the Transportation Research Board, currently serving as Section Chair for the Research and Education Section, and recently completed a six-year term as chair of the Committee on the Conduct of Research. She is also a member of Women's Transportation Seminar (WTS), serving on the Steering Committee for the joint WTS/DOT initiative for advancement of Science, Technology, Engineering, and Mathematics (STEM). She has previously held positions on the National Board of Directors, the International Advisory Board, and the local WTS Minnesota Chapter Board.

Ms. McGinnis holds a Bachelor of Science degree in Civil and Environmental Engineering from the University of Wisconsin and two Masters degrees (in Public Affairs and Business Administration) from the University of Minnesota. She is a registered engineer in Minnesota and Wisconsin. Before coming to the University, she was a project manager at HNTB, where she participated in the design of several bridges for state and local agencies.

From MPR Money for motorized recreation too much, some Minnesotans say | Minnesota Public Radio NewsQ

Minnesota's gas tax raised $745 million last year.

The state constitution says the tax dollars collected on gas that goes into vehicles using public roads must go to the highway fund. But the legislature has interpreted that as meaning the tax on gas going into boats can go towards boat landings; taxes for gas in [All Terrain Vehicles] can go to ATV trails.

...

ATV owner and chair of the Senate Tax Committee, DFLer Tom Bakk of Cook, says the system is fine.

"It's based on the number of machines and the average number of gallons of gasoline consumed, or it's based on some survey," Bakk said. "You have to base it on something. And it just plugs into a formula, and I think it's pretty fair."

From NY Magazine Can the MTA Revolutionize the City's Bus System? -

A nice story on Bus Rapid Transit in New York.

You would never guess it from the dispiriting news coming out of the MTA, but if you want to see the future of New York, then head up to the Bronx and take a bus. This is not the future of New York in which everyone has a solar-powered jet pack that takes them high over the city's organic farmyards. Nor is this the apocalyptic future in which the final few New Yorkers with health care live just beyond the moat that surrounds what was once called Yankee Stadium. This is the future as seen in a new bus line: the Bx12 Select Bus Service, or SBS, for short.

More on risk compensation from WaPo Traffic study sees shades of gray in yellow lights summarizes a study from U of Cincinnati

The longer the yellow persists, the more likely it is that drivers will not stop, said Zhixia Li, an engineering PhD student who worked on the study with his professor Heng Wei. In fact, he said, with a long yellow, "stopping is more dangerous," because other drivers are likely to keep going through the yellow, and someone who opts to stop runs a greater risk getting hit from behind.

The WaPo article doesn't actually say this is risk compensation, but drivers familiar with an intersection will be familiar with the length of yellow, and the longer the yellow on average the greater the chance of making it.

From Lisa Schweitzer: Sustainable Cities and Transport blog HSR's energy/emissions promise and peril

Reviewing a recent study (Horvath and Chester (2010) "Life-cycle assessment of high-speed rail: the case of California" Environmental Research Letters 5 014003
doi: 10.1088/1748-9326/5/1/014003), Dr. Schweitzer notes of HSR:

Being the cleanest mode per passenger hinges on getting a critical mass of people using it. The timeframe for payback on emissions invested in the colossal investment: about 70 years. I won't see it, but my students might.

Ok, so this is better than Charles Lave found for BART (Lave, Charles. 1976. The Negative Energy Impact of Modern Rail-Transit Systems Science, February 11, 1977. Vol. 195, pp. 595-596.) , which required even more construction underground, but it is not a good payback period by any means. And this is assuming conventional modes as competition. Remember, you have to skate to where the puck will be, not where it was.

High Speed Rail as religion - nice post on the problems with HSR forecasts, and the evangelical aspects of HSR promotion.

"Well, I don't know how to refute a claim about what it's going to be like waiting for a train in California in 2035. I have no idea what the headways will be in 2035. I don't know what good it will do to see a real high speed train, either. I've seen some, I've ridden some, and they're great. So are Ferraris". ... "No one knows how much tickets will cost. No one knows how much business travel will be replaced by telecommuting. It's the future! We have no idea what is out there. "

Note: title of this post from comment section of King's post.

Interviewed by Jon-Erik Lappano about HSR in US and Canada: on Slow Train Coming

Via Greater Greater Washington Group to show car that can be driven by the blind

July 2, 2010 - 6:38am

By KEN THOMAS
Associated Press Writer
WASHINGTON (AP) - Could a blind person drive a car? Researchers are trying to make that far-flung notion a reality.

The National Federation of the Blind and Virginia Tech plan to demonstrate a prototype vehicle next year equipped with technology that helps a blind person drive a car independently.

The technology, called "nonvisual interfaces," uses sensors to let a blind driver maneuver a car based on information transmitted to him about his surroundings: whether another car or object is nearby, in front of him or in a neighboring lane.

If you are going to do all that, why don't you take the person out of the loop entirely for control and navigation? No offense to the visually impaired, but wouldn't it be easier to have a car that took anyone to their destination without involving humans in steering. The car itself derives from Virginia Tech's DARPA Urban Challenger entry. The last thing we need to do is insert more potential sources of error (sensors + feedback systems) into the system. We should be looking to take them out. As proof of concept, I suppose it is a useful learning exercise, but as something that aims to be deployed, this seems like the wrong technology path.

With the rise of texting while driving, phone calls while driving, make-up while driving, shaving while driving, reading while driving, etc., it is clear most drivers really would rather be doing something else with their eyes and brains than keeping them on the road.

Speaking of standardization ... I am not much for MS products, but this seems genuinely useful: Microsoft tech allows sticking batteries in any way you want

Microsoft announced a hardware solution that will allow users of portable devices -- digital cameras, flashlights, remote controls, toys, you name it -- to insert their batteries in any direction. Compatible with AA and AAA cells, among others, the patented "InstaLoad" technology does not require special electronics or circuitry, the company claims.

Now if they could solve the drive on the left/drive on the right problem, they will have made a major contribution.

From David Metz's Limits to Travel blog: Peak Car?

I read with interest Phil Goodwin's Comment piece in Local Transport Today of 25 June in which he introduced the concept of 'peak car', and look forward to his promised further exposition. In the meantime, let me observe that as far as London is concerned, peak car use came and went at least fifteen years ago, when none of us noticed. Transport for London's most recent 'Travel in London' report records a steady decline in private transport's share of trips since at least 1993 (then 50%, 41% in 2008). Correspondingly, public transport's mode share has risen from 24% to 33%, while walking and cycling have been steady at about 25%.

I read the beginning of Goodwin's piece, but it is behind a registration wall.

It begins:

Rail, bus and tram use all peaked and then declined, so why do so many people assume that car use will either keep rising indefinitely or reach saturation and a 'steady state' condition?

I agree with the general point. But it must reach saturation before it drops. Whether it drops quickly after the peak, or slowly, depends on specific conditions. London suggests the drop may be faster rather than slower.

As gas prices drop and if the economy recovers, I expect we will see somewhat more travel by car in the US than the past couple of years, but the rate of growth from the 1990s and before is a thing of the past (unless travel by car gets much faster).

Review of "Bay Area/California High-Speed Rail Ridership and Revenue Forecasting Study" (pdf) Final Report Prepared at the request of the California Senate Transportation and Housing Committee, Submitted to the California High Speed Rail Authority, Prepared by: David Brownstone, Mark Hansen and Samer Madanat, Institute of Transportation Studies, University of California, June 30, 2010

The Executive Summary of this report is below. In short, the demand forecasts likely mis-stated demand (and thus profitability) of the proposed California HSR for a variety of reasons. The error bands are likely to be much larger than reported.

Executive Summary

"We have reviewed the key components of the California High Speed Rail Ridership
Studies. The primary contractor for these studies, Cambridge Systematics (CS), has followed generally accepted professional standards in carrying out the demand modeling and analysis. Nevertheless we have found some significant problems that render the keydemand forecasting models unreliable for policy analysis. This Executive Summary describes the most serious problems. The body of this report elaborates on these problems and describes additional concerns we have.

In broad terms, the approach taken by CS includes a model development phase and a model validation phase. In the model development phase, both historical data and survey data were employed to develop a mathematical model of interregional travel. The individuals surveyed were interregional trip makers. However, the mode choices of the individuals surveyed were not representative of California interregional travelers. For example, nearly 90% of long distance (over 100-mile) business passenger trips are made by car, while 78% of the long distance business travelers sampled for the study were traveling by air.

The travelers in the sample were asked a series of questions concerning the mode choices they would make for the interregional trip that they were making at the time they were surveyed, under various hypothetical values of travel time, cost, service frequency, and service reliability for each modal alternative (auto, air, conventional rail, and high speed rail). In analyzing the data, the fact that the mode shares actually used by the travelers were not representative of traveler population was not taken into account. Since it is likely that travelers on different modes attach different degrees of importance to different service attributes (e.g. air travelers care more about travel time than auto travelers), it is likely that the resulting model gives a distorted view of the tastes of the average California traveler.

CS attempted to adjust for this problem in the validation phase, by making sure that the model accurately replicated the observed market shares for the existing travel modes in the year 2000. Model predictions of trips by mode were compared with observed values. Parameters obtained in the model development phase were adjusted in order to obtain good agreement between predicted and observed values.

Unfortunately, the methodology employed by CS for adjusting the model parameters has been shown to be incorrect for the type of model they employed. The parameters are therefore invalid and the forecasts based on them, in particular of high speed rail mode shares, are unreliable. (It should be noted that at the time CS performed the study the incorrectness of their adjustment method was not known.)

We found other problems in model development and validation. CS changed key
parameter values after the model development phase because the resulting estimates did not accord with the modelers' a priori expectations. While this is frequently done in this type of work, it is important that the a-priori expectations be based on experience with like contexts. Unfortunately, some of the a-priori expectations used by CS are valid for intra-regional, but not for inter-regional ridership models. Specifically, the modelers increased the parameter for headway (the time between successive aircraft or train departures) and set it to a value typically found in intra-regional travel demand models. This adjustment made the predicted shares of the travel modes very sensitive to changes in frequency.

Another problem was that CS employed a model structure that does not allow for
travelers to choose between high speed rail stations, thereby exaggerating the importance of having frequent service at the single station that is judged to be "best" for a given trip.

Together with the inflated value of the headway parameter described above, this
unrealistically favors alignments that avoid dividing services onto branch routes, such as Pacheco. Correcting this deficiency would almost certainly reduce, although probably not eliminate, the ridership difference between the Pacheco and Altamont alignments found in the CS study.

In the model validation phase, several other parameters of the mathematical model were adjusted. As a result of this process, many of the model parameters were assigned values that were considerably different from those obtained in the model development phase. In some instances changes to the model parameters were informed by professional judgments of the consulting team as well as the goal of replicating observed behavior.

The resulting "validated" model, which is used to generate subsequent high speed rail
ridership forecasts, provides reasonably accurate "backcasts" for the year 2000, reflects
certain patterns of behavior observed in the traveler surveys, and accords with
professional judgments of the consultant. However, the combination of problems in the
development phase and subsequent changes made to model parameters in the validation phase implies that the forecasts of high speed rail demand-and hence of the profitability
of the proposed high speed rail system-have very large error bounds. These bounds,
which were not quantified by CS, may be large enough to include the possibility that the
California HSR may achieve healthy profits and the possibility that it may incur
significant revenue shortfalls. We believe that further work to both assess and reduce these bounds should be a high priority."