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Washington Finds Computer Simulation Unreliable
Toadpipe writes "Washington State Court of Appeals reverses a conviction in which a computer simulation had been the main evidence. Quoting 'At issue was PC-Crash, a computer program distributed by Vancouver, B.C.-based MacInnis Engineering Associates. The program recreates traffic collisions using simulations and reconstructions.
"PC-Crash had not been validated for the purpose for which the evidence was offered, simulation and prediction of multiple-occupant movement within a vehicle during a multiple-collision accident," the Court of Appeals said in ordering a new trial. "There is no general acceptance in the relevant scientific community of the use of the PC-Crash program for the purposes to which it was put."' Here is
the Court's opinion."
uncertified.
Anyone can say that they're an expert. The court system requires that if you're going to present evidence, you better have some credentials. This program, apparently, did not have the proper credentials.
Every part on a car would need to be tested for strength, width, height, depth, shape, mass, the connections holding it to another part, and that bolt tested...You get the idea. You would also need the conditions that happened the second the crash occured. Road type, amount of friction, temperature, slope, etc. As a juror I would never trust a computer simulation.
The program has not been validate for accuracy of what it simulates by the community at large. Therefore, it was dropped, and it cannot be accepted as evidence. I don't see this story as newsworthy.
Both people would be alive if they had been wearing seatbelts instead of being flung from the car when they crashed.
I know, I may have to turn in my /. account.
/sarcasm off
I would like to see more of this kind of common sense in life today.
The story states both occupants were ejected from the car in the accident. The prosecution is quoted as saying their key element of the case was that part of the passenger door was melted on the dead guy.
So which was it? Did the dead guy stay there and take the burn, or get ejected? Did the car sit for awhile burning, and take off again?
I will make the specific conclusion from the vast amount of data in the article that there was enough doubt to go around in this case.
To often attorneys for both sides put up a George Lucas light show in order to sell their version to a jury. Matters are not helped by the fact that jury selection all to often resembles a Jerry Springer casting call.
I've seen the software in question used in a trial (once). What I saw seemed to be a believable representation of an elastic collision between vehicles. At no time were there any renderings, or mention of what happened INSIDE the vehicles. But then again, you know what they say about prepared demos...
Even the summary belies the headline (and the article torpedoes it). The conviction was overturned because the software was not validated for the use for which it was used. The court made no comment on its reliability...they left that up to the scientific and engineering community. Based solely upon the court's comments and the article, it sounds like a good decision to me.
=h=
I have a more general problem with red-light radar (and most red-light radar) - it's "teaching to the test." Or in this case, "enforcing laws that are easily mechanized, not laws that are most critical to public safety."
The biggest problem I face on the road are tailgaters and the guys who cut me off at interstate speeds and the morons who barrel out of parking lots at 20 mph without checking for traffic and the idiots who think "right turn on red" has right of way over people already on the road. Hell, even the superjock riding his bike far too fast for me to see him approaching as I cross the bike path... and he wrongly believes that he, not I, have right of way. (Pedestrians do, but in this state mounted bikes are "vehicles" and bike paths are "secondary roads.") As if it will matter when he hits my car (or vice versa), other than me suing his estate to repair my car's paint job.
People who run red lights or are speeding between lights on limited access roads? Not A Problem. Maybe once every few years I'll nearly get clobbered by some moron who goes through an intersection at high speed long after the light changed, but that's reckless driving, not merely running a red light. The latter should remain illegal, but a low enforcement priority unless it's an ongoing serious problem at a specific location.
So why do we see more and more red-light X systems? Because they're cheap revenue sources. To actually make driving safer you have to hire more cops and put them in more unmarked cars and get them out on the street where they can nail the guys who really are hazards to other drivers. Not guys going 45 in a 35 zone because that's what the heavy traffic is doing and it would be far more dangerous to obey the law than to break it. Or the guy who's behind a truck and doesn't know the light has turned red until he's already in the intersection.
How long until the laws themselves are written on the basis of what's easily enforceable, not on the basis of what harms others?
And the guy in Denver who put a photo-radar system on the interstate onramp where traffic is always at least 15 mph over the posted speed limit? The cop who lectured my HS class wants to talk to you - he assured tens of thousands of us that no cop would ever, under any circumstances, ticket us for going over the speed limit in order to merge with traffic. (We were supposed to gradually slow down once merged.) Ticket or being flattened by a semi? Hmm, which will it be? Ticket or being flattened by a semi. Gee, that's such a hard decision. Not.
For every complex problem there is an answer that is clear, simple, and wrong. -- H L Mencken
Who's the victim?
Do you exceed the posted speed limit?
What defines it as a crime when it hasn't yet been through due process?
It's the job of the constabulary to enforce laws in person to protect the public, and to investigate real crime that has already occurred. Photo Radar for speed enforcement is a stupid idea, and just leads to people finding out where the cameras are that day, speeding everywhere except by the cameras. Traffic used to even require an officer to serve one with a court notice (the traffic citation), same as an officer picking up a wanted criminal to force a court appearance. Many cities don't even use the police departments to run photo radar, they contract it out to companies, who give the city a portion of the money collected. One such company is American Traffic Systems, who has operated in Scottsdale AZ and San Diego CA if memory serves.
By not receiving instant citation, the accused has no opportunity to place any importance on the memories that might help them form a defense. The prosecution/plaintiff is rarely forced to appear in court either, let alone testify to remembering the vehicle as it sped by, or any of that, like a real officer is required to do. A real officer is required to take an oath that he or she isn't committing perjury when they testify. A picture sent to the court isn't, and should be thrown out if the prosecution/plaintiff does not appear to press their side.
Photo Radar is treating people as guilty by default, without requiring individual explanation, or without an arraignment, pre-trial conference, and trial. It's a travesty to justice and a continual erosion of the rights of citizens by the government.
Do not look into laser with remaining eye.
This is something I have been wanting to write about for some time - in short the premise for my question/argument is: since the general public (to include the professional community of disciplines outside of IT support/development) has been exposed to so much "fuzzy" logic when dealing with computers, has this in fact relegated the computing professional community to explain itself over and over again for mistakes in software or related hardware? In other words although the general public very much believe in scientific research and forensic/medical "science" they are more likely to question computer related scientific findings as mentioned in this article? I mean really where are all these people going to place the frustration of having to close all those pop-ups? - Any help?
... if music be fruit of love, play on
I'd rather take the money and research ways to reduce our emissions rather than take the money to pay for our emissions and have to pay MORE to reduce them.. But that's just me. This is one of the few things I agree with our current "administration" on.
In related news, the Slashdot community have dismissed the post's title - "Washington Finds Computer Simulation Unreliable" - as being inconsistent with the article, or indeed even the summary of the article directly beneath the title.
At issue was the word "Unreliable", which implies some comment on the accuracy of the software in question. The article, however, consistently states that the software "had not been validated for the purpose for which the evidence was offered", a far more sensible claim.
"Titles of Slashdot posts have not been validated for the purpose for which this one was offered, simulation and prediction of the content of the article itself," a Slashdot representative stated. "There is no general acceptance in the relevant online community of the use of article titles as a substitute for R-ing TFA."
CowboyNeal was not available for comment.
Sounds good. We're all interested in your upcoming citation of peer-reviewed studies demonstrating the positive impact of speed enforcement on traffic safety.
Oh, wait. There aren't any. Bummer.
X-Plane is usable for instrument, commercial, and airline pilot cert training (linky). Of course, "actually LOGGING this time requires you to be in a Motus full-motion sim (price tag: about $150,000.00) with an instructor" - but still, MSFS isn't rated for jack shit. It's just a game.
Facts do not cease to exist because they are ignored. - Aldous Huxley
Correlation is not causation.
Example: I started losing weight around the same time as I started exercising. Because I started exercising, I lost weight.
The logical fallacy is that two events are linked when there's nothing to link them other than their concurrency. There are other possible explanations, such as dieting, intestinal parasites, or other diseases. Regardless, I don't need to suggest alternate explanations to show the fallacy, simply the fact that there's no illustration of cause through effect is enough.
Dieting is what actually caused the weight loss. I carefully measured what I ate every day, calculated how many calories a day my body requires, and scheduled meals to reduce my calorie intake by 1000 calories per day and charted on the calendar what my target weights should be at the end of the week, then confirmed that they were so using a scale. To rule out faults in the scale, I used a control object whose weight it can be assumed stayed the same over the same period of time. In spite of all of this, there could be other alternate explanations for my weight loss, but there's a definite difference between this explanation and the blind faith used in the previous paragraph, and also the blind faith in accepting the global warming arguments.
What's important about my statement is that my methods are documented, faults can be pointed out, and countermeasures can be taken and the trial repeated. Others can repeat the tests too, without limit, and should they verify my results, we can start saying that yes, dieting does lead to weight loss, with authority.
Does this happen with the global warming theories? I haven't seen it, but I'll admit that I haven't looked too hard.
You ought to be able to do a monte carlo simulation to obtain a probability distribution on the result. I.e. run the simulation with a large number of random but exact values within the uncertainty of the initial conditions, and count the results. If 80% of the simulations end with a broken leg, that is a likely outcome.
Of course, you would still need to validate the results of the monte carlo simulation on (lots of) observed data, both to see if you got all the relevant factors in the determinstic model, and to see if your estimate on the uncertainty of the initial conditions is reasonable.
When you assume that you cannot determine causality, the best you can do is to create a theory that stands up to testing.
In fact, you cannot say that your dieting is the cause of your weight loss. It may have been coincidence. The best you can say is that it is 100% correlated with a large sample set (and thus high confidence).
Example:
Observation: I started exercising
Observation: I started to lose weight.
These observations are 100% correlated.
Hypothesis: Exercising causes weight loss.
Testing: Exercise, then measure weight.
If weight is lost, this adds weight to the theory.
If weight is gained, the theory needs to be thrown out or reworked.
A theory is a working hypothesis that is considered probable based on experimental evidence or factual or conceptual analysis and is accepted as a basis for experimentation (Mirriam-Webster's Medical Dictionary)
In the case of global warming, of course, this is more complex-- There are many many more factors in making the planet warm up or cool down than there are in making you (or me) gain or lose weight.. And many of them are more difficult to measure. Nonetheless, we do have theories that have not been disproven with any real confidence.
More extreme example: I have a hypothesis that jumping out of an aircraft at 30,000 ft. without a parachute is not survivable.
If my theory is wrong I'll survive (which is good), however testing it would be bad should it prove to be true. Not testing this theory is then, perhaps, the best alternative.
The thing about cars is that they can kill or maim. _Far_ more people die or end up crippled in car accidents yearly than died in the 9/11 terrorist attack. More die or end up crippled in car accidents than in violent crimes.
That's why those laws are there, and that's why those cameras are there. I'd hardly discount that as "enforcing laws that are easily mechanized, not laws that are most critical to public safety." It _is_ critical to public safety, and if it can be easily mechanized, I for one am all for it.
And here's my take on all those "waah, the police is evil because they don't let me go 'only' 20mph over the speed limit" morons: do the maths folks.
Kinetic energy is proportional to the _square_ of the speed. Friction however can only dissipate that energy _linearly_ with the braking distance. So the braking distance is increases literally with the _square_ of the speed.
A 40% increase in speed _doubles_ the braking distance.
Here's a _fact_: if you have two identical cars, car A going at 50 km/h (the speed limit in cites here), and car B doing 'only' 70 km/h, car B needs _double_ the braking distance to stop. In fact, at the point where car A stopped, car B is still going at 50 km/h.
So when that moron goes at 20mph out of parking, or when that idiot jock on the bike goes in front of you, the 50 km/h car might stop and save a human life where the 70 km/h will kill or cripple.
And for what?
Most of the time streetlights are synchronized anyway. Someone who obeyed the speed limit will just go through the streetlights with less stress (on themselves _and_ the car), while the 70 km/h macho cretin will just have to brake and accelerate all the time... and still not get home any faster.
So all that endangering others' lives was for... nothing whatsoever.
So here's my take. Forget revenue generation. I'd like to see some public executions. Yes, I'm talking death penalty. Have them swinging by the neck from the streetlight pole. That would serve as a better warning to others than the cameras.
A polar bear is a cartesian bear after a coordinate transform.
A couple of years back a guy ran over and killed a little girl very near my home. This young man was a speed enthusiast, drove a powerful BMW and had "Stockholm Getaway" (a video of crazy speeding through a city) in the glove box. When the accident happened he was speeding through a red light.
Those are the facts. Now, to make this more interesting, let's presume that he had a habit of speeding and running red lights. It's probable that he wouldn't have got caught, at least not often, since there are not many traffic cops around here. My take is this: if he had had a larger chance of getting caught of speeding and running red lights, he probably wouldn't have done it so often... maybe not in that particular intersection on that particular day.
You probably guessed that we disagree on 'victimless' crimes.
How is polluting less, or at least differently, going to "terminate their economic development"? Isn't rising to a technical challenge something that our brilliant global economy is supposed to be able to manage, what with Innovation and Freedom and all that?
Mind the Gap