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The Humans Crashing Into Driverless Cars are Exposing a Key Flaw (bloomberg.com)
schwit1 sends in a story from Bloomberg pointing out that the rigid adherence to traffic laws and overcautious programming have caused self-driving cars to rack up a crash rate twice that of an average human driver. "This may sound like the right way to program a robot to drive a car, but good luck trying to merge onto a chaotic, jam-packed highway with traffic flying along well above the speed limit. It tends not to work out well. As the accidents have piled up — all minor scrape-ups for now — the arguments among programmers at places like Google and Carnegie Mellon University are heating up: Should they teach the cars how to commit infractions from time to time to stay out of trouble?" While the autonomous vehicles aren't at fault in these crashes, their relative unpredictability on the road are nonetheless leading to more accidents than expected.
Which is a great theory, but the reality is that if the speed limit is set very low on a road for no apparent reason then a lot of drivers won't respect it, and unless you can and will enforce that limit strongly and consistently, that is unlikely to change. Putting the remaining drivers -- those who do want to be responsible and safe -- in a position where they have to choose between breaking the law and driving as safely as possible, is bad law-making.
Actually, you don't need to enforce it consistently. You get as much compliance, but at a lower cost, if you haphazardly enforce it. If the driver doesn't know when it will be enforced, they will comply. It only takes the possibility of being caught that triggers the behavior.
Besides, all of the robot crashes have been minor fender benders. It may be worth living with double the rate of those if the serious crashes that injure people are perhaps halved.
Bingo. The relevant question is "What is the crash rate involving injury?" If that is lower, then it is reasonable to accept a higher rate of non-injury crashes. Trading injury for property damage is a good deal, since increased property damage can be handled by increased insurance costs on non-automated drivers.
Really, when will idiot philosophers get over their wet dream of getting people to condone murder? There are more important and useful questions to ask, but all I keep hearing about is some stupid variant of the trolley scam.
The trolley is a thought experiment, but the situation is not totally out of the way. Nearly every time there is a drone strike, or an air strike, or an encounter between a US cop and a dark-skinned person, plenty of innocents are killed. One can only hope that the people responsible at least convince themselves (if nobody else) that in the long term this saves lives, instead of acting purely reactively.
Michael Sandel's Justice course at Harvard is online, and is full of interesting discussions of moral dilemmas. There is not always a perfect solution, but there is a lot of value in thinking about the problem.
Stephan
If you're not overtaking, you have no business being in that lane. That's what the outer lanes are *for*. It's people who don't understand that simple rule that cause accidents. Undertaking is illegal e.g. in the UK for a reason.
Oh there is a reason, it just has nothing to do with safety.
Or there is a reason, it has to do with safety, or with optimising throughput, or some other valid concern, but that reason is not obvious to every dummy driver on the street.
The throughput argument bears repeating. Many drivers don't understand this, but sometimes you can get more people through a bottleneck (AND have fewer accidents) if everyone drives more slower at a constant speed than if everyone is trying to drive faster at the same traffic density. This is particularly true when you have a high variability of vehicle speeds, like in a mountainous area where trucks are forced to go slower or in an urban area where frequent incoming and outgoing traffic at exits often travel at different speeds from the rest of the highway.
For example, if you're driving on a highway through an urban area and they lower the rush hour speed limit to 45 mph (some areas now are adopting such dynamic speed limit signs), the idea is that if cars actually go 40-45 mph, the road will actually be able to handle the amount of traffic while also allowing all the people merging on, getting off at exits, changing lanes, etc. at a safe speed.
If, instead, everyone tries to drive 65-70 in the same area, what can happen is that the merging or changing lanes will eventually cause someone to cut someone else off, which causes sudden braking, which then causes some tailgaters behind them to brake suddenly, others follow and overcompensate because they were going too fast and suddenly see much slower cars, and within a few minutes you have a "traffic wave" of stop-and-go traffic backed up for a few miles which might take a half-hour to resolve, where throughput is dramatically reduced. (How many times have you gotten to the end after sitting through 10 minutes of such stop-and-go traffic waves, and there's nothing there -- no accident, no merge, etc.? This is often the kind of thing that happened.)
At a slower speed, the slower car may not have been forced to "cut someone off" in the first place, or if he does, the impact of a bit of braking may not cause such massive changes and overcompensation. Traffic thus recovers faster and throughput is maximized.
I'm tired of morons thinking they understand traffic engineering. The speed limit should be set at around the 80th percentile of car speed on the road. If the 80th percentile is 20mph faster than the speed limit, the speed limit is broken; hell if its 10mph slower than average its being set at about the 30th percentile likely; so 70 percent of people are speeding on that road. Time and again studies show that most people drive a safe speed for the road and conditions regardless of the speed limit, whether faster or slower.
You on the other hand think that the speed limit is set by some omniscient being that knows whats best for the road and sets it and then the majority of people, being sheep, break it and lead to evil consequences. Because hey OBEY the limit, its not a retarded limit that needs fixed, because YOUR BETTERS SET IT.
I'm sure you'd prefer your cars designed by some randomdood since you prefer your roads and speed limits not designed by a qualified engineer either.
It's not silly. It actually lets you go faster, and more safely with less road congestion. Why? Because slower traffic ends up on the inner lane, going progressively faster to the outer lane. So it's actually not silly at all in heavy traffic. It means slow traffic doesn't impede faster traffic, and it means that the driver can make certain assumptions about the driving conditions, e.g. they won't be overtaken on the inside, which makes lane changes easier and safer. It makes driving on fast roads predicable since you know how the other traffic will behave.
Of course, there are some idiots who don't know how to drive and hog the middle lane, and are universally hated for it; they get pulled over by the police since it's actively dangerous to the other traffic--because it can force people to undertake.
When you look at footage of road accidents in countries without this rule, what's immediately clear is that the driving is far more erratic since it's an unconstrained free-for-all, and that makes accidents more likely, as well as reducing the effective safe speed on the road.
You are quoting research that a graduate student of mine actually helped produce (not the original, but the followup in 1997), but you are missing the point. Yes, people will drive at speeds they are comfortable with, that is not in dispute. However, that is assuming there is no enforcement of existing limits. The research shows that if enforcement is factored in, most people will drive within five miles of the speed limit. It further shows, that this leads to a more consistent speed among all drivers on a given stretch of road and as such improves the number of vehicles per mile per hour per given stretch.
You are correct, posting speed limits does not affect overall speed. That is, unless those speed limits are actually enforced. If you aren't going to enforce them, then why post them.
It should be simple to understand that rules without consequences don't change behavior. OTOH, removing consequences tends to encourage the behavior the rule was meant to address, which is where we are today with speed limits.
The reality is that the faster vehicles go, the longer they take to stop or if the driver is distracted the further the vehicle travels until attention is focused. Couple that with the aging population, where reaction time is decreasing, and you have a recipe for disaster. One solution, albeit very costly, is to force people into driving autonomous vehicles. Of course, that will take years before they are ready and in sufficient quantity to make a difference (look at the hybrids, even government subsidies weren't enough to get sufficient people to buy them where they were economical and they were vastly cheaper than autonomous vehicles are expected to be). Or, a simpler solution, available today and proven to work is to enforce the traffic laws.
Again, I agree, just changing the number on the sign won't change peoples speed habits. However, enforcing the number on the sign has been proven to do so.
If you're driving the speed limit, stay the fuck out of the left lane. It's not a complicated concept. If you need to drive slowly in order to drive safely, by all means do so, but that doesn't give you the right to become an obstacle to navigation. "In the flow of traffic" is always the safest speed, assuming your reactions and willingness to focus are up to it.
Socialism: a lie told by totalitarians and believed by fools.