Waymos crash less than human drivers

Serious crash rates are a hockey stick pattern. 20% of the drivers cause 80% of the crashes, to a rough approximation. For the worst 20% of drivers, the Waymo is almost certainly better already.

Honestly, at this point I am more interested in whether they can operate their service profitably and affordably, because they are clearly nailing the technical side.

For example data from a 100 driver study, see table 2.11, p. 29. https://rosap.ntl.bts.gov/view/dot/37370 Roughly the same number of drivers had 0 or 1 near-crashes as had 13-50+. One of the drivers had 56 near crashes and 4 actual crashes in less than 20K miles! So the average isn't that helpful here.

Hmmm, perhaps a more-valuable representation would be how the average Waymo vehicle would place as a percentile ranking among human drivers, in accidents-per-mile.

Ex: "X% of humans do better than Waymo does in accidents per mile."

That would give us an intuition for what portion of humans ought to let the machine do the work.

P.S.: On the flip-side, it would not tell us how often those people drove. For example, if the Y% of worse-drivers happen to be people who barely ever drive in the first place, then helping automate that away wouldn't be as valuable. In contrast, if they were the ones who did the most driving...

With a distribution like this, percentile would be misleading, though

isnt it a bit odd they always seem to be at the scene of a crash but somehow always a victim?

No? If they cause less accidents then people will hit them more often than they hit other people.

My car has been involved in more fender benders while parked in perfectly legal spaces than when I was driving it.

However, such a pattern can also occur if the Waymo cars are stopping more abruptly or frequently than a human driver would be expected to.

In such a case, they might not be considered legally at fault, but they would still be, in practical terms, a significant cause of the crash.

No, tailgating would be a significant cause of the crash.

A driver -- legally, logically, practically -- should always maintain a safe following distance from the vehicle in front of them so that they can stop safely. It doesn't matter if the vehicle in front of them suddenly slams on the brakes because a child or plastic bag jumped in front of them, because they suddenly realized they need to make a left turn, or mixed up the pedals.

Oh, I fully agree—like I said, legally they're not at fault, because you'd more or less have to be tailgating and/or inattentive to crash into them just for braking unexpectedly.

But if there's an existing system and culture of driving that has certain expectations built up over a century+ of collective behavior, and then you drop into that culture a new element that systematically brakes more suddenly and unexpectedly, regardless of whether the human drivers were doing the right thing beforehand, it is both reasonable and accurate to say that the introduction of the self-driving cars contributed significantly to the increase in crashes.

If they become ubiquitous, and retain this pattern, then over time, drivers will learn it. But it will take years—probably decades—and cause increased crashes due to this pattern during that time (assuming, again, that the pattern itself remains).

Tailgating causes a great number of accidents today, no autonomous cars needed.

While tailgating is tiny slice of fatal collisions -- something like 2% -- it accounts for like 1/3 of non-fatal collisions.

We're already basically at Peak Tailgating Collisions, without self-driving cars, and I'd happily put a tenner on rear-end collisions going down with self-driving cars because, even if they stop suddenly more often, at least they don't tailgate.

And it's entirely self-inflicted! You can just not tailgate; it's not even like tailgating let's you go faster, it just lets you go the exact same speed 200 feet down the road.