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Comment by omarforgotpwd | Hacker News Reader

The issue isn't that the cars are worse drivers than humans. They're obviously going to be much better statistically. The article is just making the point that they're going to have to be programmed to break the rules just like humans do i.e. with speeding, stopping too often etc. If they are not programmed to break the rules, they will frustrate people and even cause accidents as humans try to interact with them. There's not always a good way to know that the car in front of you is being driven by a computer.

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This will be an opportunity to fix the traffic rules to be more realistic. Often, the speed limits are too low in the US, and "everybody" goes faster. This leads to the problem of selective enforcement, and people not trusting speed limits when they are really neccessary.

In contrast, I've found most speed limits in Germany to be reasonable absolute maximum limits - except on one or two places on streets I know very well. And I'm not talking about the Autobahn - if I see 70 km/h in Germany (45-ish mph), its probably dangerous to go faster. If I see 45 mph in the States, it seems to mean "everybody go 55 mph".

1. Do you want to be the local politician who says "hey, let's raise this to 55 MPH" and then on a bad weather day or just out of sheer bad luck soon after there's a major pile up and then said politician gets roasted?

1. The traffic lights need to be coordinated and that means presuming a certain speed. Now the problem is a lot of traffic lights are close enough that changing the programming of just one should ripple through the entire system and this recently (especially on a regulation making time scale) was a problem consuming extraordinary amounts of computing power.

Speed limits aren't just about safety. Lower speeds mean less noise, which is desirable to local residents in residential areas. They're the ones who local politicians are accountable to.

Decreasing speed limits is something that local politicians can use to demonstrate to their constituents that they care about them, but very rarely has net-positive effect on noise and polution.

Pollution too. Speed limits are sometimes lowered when it is a problem. Temporary, during peaks, or permanently.

The other, more cynical reason for lowering speed limits is that in many countries now, speed traps are a significant source of income for the state. Making the speed limit significantly lower than what the standard 85% rule says is a good way to extract money from unsuspecting drivers.

but this is exactly the sort of political cover the politicians need. nobody wants to be the politician that says "lets raise the speed limit here to 55MPH", but if everybody drives 55 and all of a sudden there's a bunch of self-driving cars going 50 and people are getting annoyed at the road getting blocked up, changing traffic rules to conform to reality becomes a lot more possible.

> Often, the speed limits are too low in the US, and "everybody" goes faster.

Excessive speed is the primary cause of a third of all fatal accidents and a contributing factor in at least half. Instead of training the self-driving cars to be more human, we ought to train humans to act more like the computers! Speeding is one of the stupidest norms that exists in our society. We should definitely not try to encourage it.

No, difference in speed causes those accidents:

https://en.wikipedia.org/wiki/Solomon_curve

> Speeding is one of the stupidest norms that exists in our society.

Politicians arbitrarily setting the speed limits is the root cause.

The EU has many countries which have higher freeway limits, yet lower accidents per mile driven. They also have more stringent licensing.

Yeah, that's not a great study (though it was admittedly pretty groundbreaking,) and it doesn't actually prove that there is no relation between speed and accidents. Multiple studies since the 60's have shown different results.

>Politicians arbitrarily setting the speed limits is the root cause.

Of speeding, or accidents?

> Yeah, that's not a great study (though it was admittedly pretty groundbreaking,) and it doesn't actually prove that there is no relation between speed and accidents. Multiple studies since the 60's have shown different results.

The link sourced multiple studies. The originals were dubious, subsequent ones not so much.

But the issue the Solomon curve and other similar studies points out is that humans (and largely Americans) will ignore the rules if they feel they can safely go faster.

And sure, you can't ignore overall average speed. Crashes on roads where the average speed is 100 mph are going to be much more prone to fatalities than 55 mph roads. So, there are two rough equations: Lower average speeds mean less severe crashes; speed limits set to the 85th percentile mean fewer crashes. As the speed limit is raised (from 0), there will be at least one solution that satisfies both of those equations and results in the fewest fatal crashes (if that's your goal).

In certain situations the lower speed limits can make things less safe. For example, a straight, well maintained toll road with wide lanes, clear vision ahead, and say wildlife barriers that was designed for 75mph max speeds is constructed in a state with statewide 55mph speed limits. Construction uses the latest traffic easing and safety techniques, since you don't want to construct all roads to enforce speed limits that may change in the future.

So now most truckers and cautious drivers go 55mph, while people with less inhibitions are weaving in and out of them.

Are you talking about the wikipedia link? All the subsequent studies save one that it sourced disproved the first's premise or drew attention to serious questions as to its validity. Did you read them?

Yes, but the speeding norm is partly caused by speed limits being uniformly too low in some circumstances leading to speeding being tolerated to a point and everyone making their own judgements about how fast is too fast. It would be better to have higher limits that are strictly enforced rather than lower limits that no one follows.

Did you bother reading what he said? Speed limits are lower than what is safe on many roads. Limits should be increased to the safe maximum and then the maximum should be more strictly enforced. Minimums should be enforced as well, since driving significantly below the maximum is also unsafe.

It doesn't mean increasing limits to something that is unsafe.

Counterpoint: as a German, I know that when a sign says 50kmh, everyone goes 60, and when it says 70, everyone goes 80, etc. If you go as fast as the sign says, you will most likely cause traffic.

> If you go as fast as the sign says, you will most likely cause traffic.

Counterpoint: creating traffic by going at the speed limit requires that other people on the road are going over. Both parties are to blame, but only one party isn't increasing their energy at a exponential rate (1/2mv^2).

Your interpretation of American speed limits is quite correct. Driving the speed limit on a major highway in any but the rightmost lane is dangerous due to the speed other drivers expect you to be going.

On the flip side (almost literally), I once drove around Ireland for a week. Of course my instinct was to drive slightly over the speed limit, but I quickly found 100 kph on 1.5-lane roads winding around sheep pastures with no visibility nearly impossible to safely match let alone exceed…

>The issue isn't that the cars are worse drivers than humans. They're obviously going to be much better statistically.

This isn't obvious at all.

Sure it is!

There’s a way to know they’re learning to drive or just recently got their license, why wouldn’t there be a way to know they’re driven by software?

Right, just give them a C plate.

That, or... if enough AI drivers are out there then maybe humans will just learn to live with them.

While crashing into an AI driver I may be able to blame the AI, it's still a huge pain and possible loss for me as a human.

If the reality is that AI is not leaving and they have peccadilloes, then the human drivers and legal structure will just need to adapt (something we aren't bad at).

Computers have been training humans for the past couple decades, and I see no reason for that to stop just because the computer's form factor is a car.

They should follow the law. Granting an exception is not the way the law should work, because such exceptions are arbitrary and without any sense of justice or ethics. The best way to fix a bad law is to consistently enforce it.

If two actors, one of which is following the law, has a higher risk than two actors both breaking the law, the lawbreaker is still at fault for the increased risk.

Speed limits are not just for traffic safety, but also to reduce noise pollution.

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