More PRT Disinformation

Avidor recently reprinted a comment from David Greene, a software engineer from Minnesota who doesn't think PRT can work because the computer algorithms are too complex. As a fellow software engineer, I feel compelled to respond to his post, point by point:

Greene: "The idea that computers can automatically control a distributed network of machines that by their nature have a human interaction component and that this system will work at peak efficiency with vehicles traveling inches behind one another is absurd."

What is absurd is Greene's statement that PRT vehicles would be traveling "inches behind one another". The truth is, vehicle separations are measured in dozens of feet even for very short headways, with conservative designs exceeding one hundred feet. See "PRT is a joke" is a joke" for an expanded discussion of vehicle separations for different systems.

Greene: "We have plenty of examples of much smaller and less complex systems have taken years to get right, if at all. A few that
come to mind:

- Denver airport's baggage handling system

- MSP airport's trams (which only go from one single, fixed point to another!)

- Metro Transit's GoTo card system"

None of these systems has anything to do with PRT or PRT companies. It's like saying light rail is doomed to failure because of Amtrak's financial troubles. Amtrak and light rail are at least as comparable as PRT and the Denver baggage system.

Greene: "As a computer professional, I can state with utter certainty that computers are not the magic bullet that will save us. At one level they are extremely simple machines. But at another level, they are incredibly complex. Debugging distributed software is no easy task. Programs will always have bugs. The question is, can the developer get rid of enough of the critical ones to make the system mostly functional? Is mostly functional good enough?"

First off: I never trust someone who makes predictions with "utter certainty".

As for his statement about complexity, he neglects to mention the fact that very complex distributed systems are all around us - so much so that we take them for granted. Some examples of massively distributed systems that we use every day without even thinking about it:

• The Internet - over half a billion computers on a heterogeneous worldwide network - and any one can connect to any other within milliseconds
• ATMs - hundreds of thousands of fully automated kiosks, providing financial services to millions of users. It would seem that they've worked out most of the critical bugs, despite having to integrate real time financial data from hundreds of different financial institutions.
• Inventory systems - retail giants are able to track every piece of inventory in every single store, with such accuracy that an online shopper can check store inventory, purchase an item online, and pick it up in-store within 15 minutes.

Compared to these problems, routing a few thousand vehicles on a local guideway is relatively simple. Note: I didn't say absolutely simple - certainly there are complexities in controlling a PRT system. But if we can tackle problems as complex and distributed as the Internet, ATMs, and global inventory systems, is it really such a stretch to assume we can handle PRT?

But in actuality, no assumptions are necessary. Morgantown PRT, though not technically a true PRT system, has featured automated control of vehicles on a switched track for over 30 years, without incident; Cabintaxi was a thoroughly tested German system which was able to route two dozen vehicles over 1.9km of guideway with 6 stations. Both of these systems were built in the 1970s, when computing power was measured in kilohertz. More recently, ULTra has logged thousands of miles of testing at its Cardiff, UK test track. All of these systems have carried passengers.

In other words, it is absolutely absurd to "state with utter certainty" that PRT computer control will not work - since it's already been demonstrated to work by multiple independent groups.

Greene: "In technical terms, the problem of optimally scheduling a distributed network of traveling objects is likely NP-complete (I haven't done the formal analysis). That means that the computer will have to make guesses and I can guarantee that it will guess wrong in some cases. That doesn't mean the system will break down, but it won't always achieve the peak efficiency that its promoters proclaim."

This is mostly flat-out wrong, despite Greene's "guarantee". PRT routing and control algorithms are among the most studied and simulated aspects of PRT research. In addition to the hundreds of thousands of miles of real system testing done on Cabintaxi and others, in-depth simulation studies have also subjected these routing algorithms to billions of miles of testing, validating the algorithms under the most extreme loads.

Modern algorithms feature asynchronous control, which is decentralized, scalable, and flexible. Vehicles can be largely autonomous, especially when it comes to maintaining safe distances, so regional controllers are not burdened with every safety detail. Central control can focus on global optimizations to optimize routes and reduce congestion.

Is every single passenger guaranteed an optimal ride? Of course not - no transportation system can make such a guarantee in heavy loads. But extensive analysis, simulation, and testing have shown that these systems will operate at or near optimality for all passengers.

Greene: "A system like PRT will need many layers of redundancy, and that adds cost."

Nonsense. Computers are cheap, as are most of the mission critical components that would require redundancy. The vast majority of the cost of PRT is in guideway and construction materials, and in the manufacturing of the vehicles. Adding a few redundant components to such a large infrastructure only adds a trivial amount of cost.

Greene:"I just don't buy the claim that private companies will pay for it and make a profit. If that were the case, why does PRT need any subsidy at all?"

Light rail requires subsidy for both construction and operations. That doesn't stop us from building more light rail. PRT, on the other hand, offers the promise of providing much better service (try taking the train at 3:30am on a Sunday morning) for less operating cost, and may even be able to recoup the construction costs. At worst, if all the projections are terribly wrong, we'd wind up with just another subsidized system like LRT - only more convenient and available 24x7.

Private companies haven't embraced PRT for the simple reason that it's too much of a corporate risk to sink hundreds of millions of dollars into. Big companies, like governments, are wary of any radical challenge to the status quo.

Greene: "I work in the supercomputing industry developing the software that users need to develop their applications. I also do some high-level hardware architecture work. A system like PRT will need something equivalent to a low-end supercomputer to work. I know how difficult it is to get these systems to function."

This is absolutely, ridiculously false. A low end supercomputer? Come on! The most complex PRT computations are routing and trajectories, neither of which requires anything near a supercomputer. Computers have been calculating trajectories since World War II! Heck, an iPod could probably handle the load of a small PRT network!

As proof of this, I again reference Cabintaxi - which was fully controlled by computers five years before the original IBM PC came out!

Greene: "The claims made by PRT proponents are pie-in-the-sky nonsense. They are made by people who have no real understanding of the underlying technology needs and complexities."

The only nonsense here is Greene's wild assertions. He is either hopelessly misinformed, or is just another mindless follower of Avidor's propaganda campaign. As a fellow software engineer, I'll give him the benefit of the doubt and assume he just hasn't done his homework.

Debunking the Lies

Ken Avidor has posted a long list of lies in his latest blog entry. I'm going to debunk each point individually:

Avidor smear: "Horns, wings and hoofs exist on different animals yet nobody has seen a flying unicorn... or a working PRT system."

What Avidor neglects to mention is that there have been working PRT systems - CVS and Cabintaxi were PRT systems that had thousands of miles of testing in the 1970s - these were fully functioning prototype systems that carried passengers in actual vehicles in an actual network. ULTra has also had thousands of hours of testing at its test track.

Avidor wants you to believe that PRT is a myth, a unicorn. He wants you to believe it has no basis in reality. He's lying.

Avidor disinformation: "Sorry, last I heard, ULTra has a few development hurdles to jump before construction begins."

Based on what? When you make a claim like that you should provide links, links, links! According to ULTra’s website, the Heathrow Pilot program is underway, with the first installation scheduled to open in the summer of 2008.

Please provide proof for your claim of "hurdles", otherwise I’m going to assume it’s yet another lie.

Avidor lie: "Anyways, what relevance does a battery-powered buggy that cannot operate in snow or ice have for Minnesota?"

According to ULTra’s website, "Approaches to ice and snow control have also been prepared for applications in cold climates." Do you even read about the stuff you slam?

Avidor propaganda: "The other would-be PRT company he mentions, Vectus is yet another sham PRT "testing facility" project. For forty years, PRT was always on the verge of some breakthrough that never happened. Here's a long list of PRT projects that never happened and never will."

Notice he doesn’t say anything about Vectus directly – he resorts to dogmatic proclamations like "there’s never been a PRT system and there never will!" Why doesn’t he post anything specific about Vectus? Because he has nothing on Vectus, so he spews generalities.

Avidor flip-flop: "Skyweb Express/Taxi 2000 never advanced beyond the shiny red pod prototype. Taxi 2000 has failed to update its news page on its website since 2004... when Olson's bills failed in the legislature. A dead website usually means a dead company."

But, just a few days ago, when he was slamming JPods, he proclaimed "Unlike the shiny red Taxi 2000 prototype, the J-Pod is obviously a joke." So which is it, Ken? Is the "shiny red prototype" a joke or not a joke? When you’re slamming JPods, it’s not; when you’re slamming Taxi 2000 two days later, it is.

This, folks, is what’s known as a flip-flop.

See also ”PRT is a joke” is a joke.

Avidor deception: "There is no technology. When Taxi 2000 sued J. Edward Anderson in 2005, Anderson claimed there were no PRT patents."

The truth is that Taxi 2000 had patents that expired. The claim that there is no technology is a blatant lie. See Dr. Anderson’s extensive discussion of this supposedly non-existent technology and decide for yourselves.

Avidor deception: "The U of M is no longer interested in PRT."

As proof of this claim, Avidor points to a blog entry by a U of M researcher who never was interested in PRT, and still isn’t. His criticism of PRT? That it hasn’t yet found a market and may have a difficult time doing so. In other words, he’s not exactly calling it a "unicorn"…

Avidor smear: "Mr. Swanson obviously hasn't ridden the Hiawatha LRT... LRT is a completely modern, state-of-art technology. PRT on the other hand has not advanced further than the concept stage which is hardly different than the 1960's concept of PRT."

Let’s digest this for a moment. Ken is criticizing PRT for not having changed much since the 1960’s, when his preferred technology has barely changed at all since the 1860s!

I also find it ironic that "state of the art" is considered a plus when speaking about light rail… but mention that PRT is a "state of the art" system and you’re labeled a wacky gadgetbahner.

Avidor smear: "…nobody wants to pay the cost o developing it and nobody wants a transportation system that requires communities to cut down half the trees on their streets for a monorail with a clear view into their bedroom windows…"

…and yet, elevated light rail is perfectly acceptable. Apparently, Avidor doesn’t care if people can see in his windows, as long as those people are inside a train and not a pod.

Avidor propaganda: "This is one of the big lies of the PRT disinformation campaign. No transit system can be built and operated without subsidy."

Let’s read into this statement: we know that light rail requires a huge subsidy in almost every case. We also know that the only acceptable form of transit for Ken Avidor is light rail. Therefore, he comes to the conclusion that all transit requires subsidy.

This, despite studies that have shown that PRT can operate at a much reduced subsidy as compared to LRT, and also provide 24x7, on demand service! So PRT provides more for less, but it can’t possibly be better than LRT, which costs more to operate and is unavailable on nights and weekends. Yet another example of tortured Avidor logic.

Avidor disinformation: "PRTistas like Swanson claim that PRT is so cool that people would pay any price to ride it. The ridership figures for monorails, the closest thing to PRT falls far short of rail transit."

Actually, monorails are much more like elevated rail than PRT. In fact, from a functional standpoint, the only difference between monorails and traditional rail is… two rails!

In fact, the only similarity between monorail and PRT is the fact that both are on dedicated guideways. In almost every other way, PRT is different:

Monorail/LRT	PRT
large trains	small individual vehicles
line haul with frequent stops	network with non-stop point-to-point travel
online stations	offline stations
reduced service during non-peak times	full 24x7 availability

PRT is nothing like monorail. The fact that Ken makes this comparison is just more proof that he really doesn't know what PRT is.

Avidor lie: "Here's a blog sums up what most transporation professionals think of PRT…"

…and then he posts a link to an anonymous blogger who references back to Avidor’s own propaganda! Where are the transportation professionals who are lining up against PRT? The folks at publictransit.us have been conspicuously silent about PRT recently. Why is that, Ken?

Pot, Kettle

Ken Avidor has written a defiant letter to the editor. Here's an excerpt:

"The Citizen published a letter from Mark Swanson that states that I am a "false expert". Mr. Swanson is attacking the messenger instead of responding to the message. Mr. Swanson then goes on to denounce me as a "left wing author" even though Mark Olson worked very closely alongside the Green Party’s Dean Zimmermann (recently convicted of bribery) to promote PRT."
(emphasis mine)

Here, in a single paragraph, we have a microcosm of Avidor's entire hypocritical campaign: in sentence one, he condemns Mark Swanson for "attacking the messenger instead of responding to the message". In sentence two, he himself proceeds to attack Olson and Zimmermann!

I actually had to re-read this twice, because the juxtaposition of these two sentences was so unintentionally ironic that I found it hard to believe it at first. But there it is, in plain English.

In Avidor's defense, personal attacks have become so routine to him that maybe he doesn't even know he's doing it. He is, after all, the maintainer of the Bachmann "fun page", which features various tasteless Photoshop hacks, as well the Luv Pod page, which ridicules the "wacky professor" and other PRT proponents, whom he commonly refers to derisively as "gadgetbahners" and "PRTistas".

And then there is the Sheffer Lang attack page, a whole page devoted to attacking this former Taxi 2000 Chairman, who can't even defend himself because he passed away tragically three years ago. And then there is the "Ned Luddington" affair, in which he created a false identity to serve as a fake source for his attacks on Zimmermann.

So is it any wonder that a personal attack (or two) slipped into his letter condemning personal attacks? It almost feels wrong to criticize him for it, like denouncing a tiger for killing his prey. Almost.

Avidor closes his letter with the following:

I welcome an opportunity to share what I know about PRT with the citizens and voters of Sherburne County in a forum or debate.

We all know what he "knows" about PRT - he presented his whole repertoire in the comment thread copied here. After we debunked every single point, he finally gave up with his traditional cop-out rejoinder, "whatever".

Something tells me he will be presenting these same talking points to the fine folks of Sherburne County - and in person, so he can spew his disinformation unchallenged.

Why is Patty Wetterling Pushing Avidor's Propaganda?

Patty Wetterling has an interesting quote on her campaign website:

"According to a column in the St. Croix Valley Press, PRT 'was little more than a stalking horse for the highway construction industry and individuals belonging to anti-rail transit groups.'"

Anyone who is familiar with Ken Avidor's smear campaign recognizes this quote: it's the foundation of his entire anti-PRT crusade. It's also a complete fabrication. Avidor has been repeating this accusation for years, without a shred of proof to back it up. He's been repeating it so long, many people think there is a factual basis, but there really is none.

In fact, I can prove that the "stalking horse" theory has no factual basis:

Early this year, Ken tried to infiltrate Wikipedia with his propaganda message. For six months, he waged war on the PRT article, insisting that his "stalking horse" theory be prominently represented. I, along with several other Wikipedia editors, fought to keep him from corrupting the Wikipedia article with unproven (and often ridiculously false) propaganda. But he did find an apparent ally in his fight: a Wikipedia administrator who favored light rail and also happened to be a huge fan of Road Kill Bill (Ken Avidor's anti-car cartoon). In the end, though, even with a sympathetic administrator in his corner, not one piece of Ken Avidor's message was kept in the article.

Why did Ken fail to spread his message on Wikipedia? Simple: Wikipedia demands evidence. Anyone can get an op-ed piece or a letter to the editor published, but when it comes to an encyclopedia, a higher standard must be met.

So, you might ask, what is the standard for inclusion at Wikipedia? Again, the answer is simple: you must provide a reference to a reliable source. That's it! A single source will do, but it has to be reliable: for instance, a published research paper in a peer-reviewed journal, or a news article from a respected news organization.

Now, consider: Ken fought hard to get his "stalking horse" theory included, and failed. Why? Because he could not provide one shred of reliable evidence to support it! That's all he had to do was provide one credible source, and he never did.

So, let's review what we know:

1. Avidor really wanted his "stalking horse" theory represented in Wikipedia article.


2. In order for it to be included, he needed to produce one piece of reliable evidence to support it.


3. To date, he has not produced that evidence, and the words "stalking horse" do not appear in the article

Conclusion: there is no evidence to support his theory; because if there were, he certainly would have produced it as evidence for Wikipedia, wouldn't he?

(Interesting side note: the minute that Avidor discovered he couldn't manipulate Wikipedia for his own purposes, he attacked the encyclopedia and its founder.)

So where did the "stalking horse" theory come from? Easy: Avidor made the whole thing up, then promoted it incessantly for years on every blog and open forum on the planet, to the point where even reasonable people take it as fact. During this relentless campaign, he used every trick in the book to "prove" his conspiracy theory: half truths, guilt-by-association, distortion, speculation. (For a good example, see David Gow meticulously dissect of one of Avidor's stalking horse "proofs".)

And it's not just the "stalking horse" that failed at Wikipedia. Search for "hoax" or "fraud" at the Wikipedia article - not there, because Avidor made it up. Not one bit of Avidor's campaign is represented there - because it's all one big fiction; only his obsessive persistence in promoting it makes it appear factual.

So, if the stalking horse theory is not real, why is Patty Wetterling referring to it as proven fact on her campaign site? I can only assume she found a convenient sound bite to use in her campaign against Michele Bachmann, and didn't bother to check the veracity of the claim.

Interestingly, she says she got the quote from the "Saint Paul Pioneer Press", 2/11/2004, and "Saint Croix Valley Press", 5/25/2006. I searched both of those press sites, and found nothing about PRT on those dates. Could it be that she is quoting an op-ed piece, or even a letter to the editor as fact? Gee, I wonder who would author such an op-ed piece?

So, Patty, are you going to remove the "stalking horse" reference from your campaign site? If you value truth and honesty in politics, I'm sure you will.

See also: "PRT is a Joke" is a joke.