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by bobthepanda 3007 days ago
From the article:

> But zooming out from the specifics of Herzberg's crash, the more fundamental point is this: conventional car crashes killed 37,461 in the United States in 2016, which works out to 1.18 deaths per 100 million miles driven. Uber announced that it had driven 2 million miles by December 2017 and is probably up to around 3 million miles today. If you do the math, that means that Uber's cars have killed people at roughly 25 times the rate of a typical human-driven car in the United States.

We have a sample size of 1, granted, but it's not looking very good. At the very least they were expected not to be less safe than humans.

2 comments

> "We have a sample size of 1..."

i'm not sure that's the right way to look at it (that uber is a sample of 1, or that the death is a sample of 1).

in this case, the metric is deaths per mile, so there are purportedly 3 million samples for uber self-driving cars, with one positive (negative?) result in that sample. you need so many samples because the positive observation rate is expected to be very low (as evidenced by the 1.18 deaths per 100 million miles driven by human drivers).

if you assume the death rate is roughly the same, you can (roughly) estimate the expected error or confidence interval with the 3 million sample size versus a 100 million known rate for human drivers. as more samples are gathered, the confidence interval gets tighter: if the confidence interval currently stands at 80% with 3 million samples (made up numbers), it might go up to 85% with 6 million samples.

You have a sample size of 1. Acknowledging that doesn't suddenly make the sample evidence of anything, good or bad :P.

Almost all the miles driven are going to be in near-ideal circumstances (daylight, no rain, good road surface, driver familiar with normal road traffic conditions and drives the route regularly). I have nearly no insight into the uber death, but I gather it happened at night. It could easily be that humans are also an order of magnitude more dangerous at night.

Of course it's evidence of something!

Suppose, as a massive oversimplification, Uber's self-driving cars crash with some constant probability P for every mile driven (i.e. a Bernoulli process).

We now have learned at least one thing with absolute confidence: P > 0.

The first mile driven before the accident, of course, also showed P < 1.

But beyond absolute certainty, we also have a better idea of the actual value of P. (Intuitively, the longer we go without a crash, the lower we suspect P to be, and for every crash, we increase our estimate of P).

If there was only one crash in 3 million miles driven, this is evidence for values of P near 1/(3 million), and evidence against values of P far from it.

Is it strong evidence? Nope! But it's evidence!

You obviously want to be technical. Technically you are correct. However, the evidence that this car is a worse driver than a human is currently so weak we're both wasting time talking about it. We need more of the stuff for it to be worth considering.

Your pedantry has managed to upset me and I would encourage you to be a little more understanding of people using language in the way it is used outside of the world of mathematics. Walking into a practical discussion of safety with an existence proof of all things is disrespectful of the fact that lives and enormous quantities of human attention are at stake.

Obviously, technically everything is evidence of something. I know that. Using the language in that sense is not going to help.

It just takes one fish in the milk, to paraphrase Thoreau.

Something happened that just shouldn't be possible, with Lidar and half-competent AI - which we use in good part because cameras don't handle low-contrast nearly as well as human eyes, say at night.

The singular of data is an anecdote, as they say.

> It could easily be that humans are also an order of magnitude more dangerous at night.

Given that the actual circumstances of the death (pedestrian crossing left to right in a large road with the car in the rightmost lane) was a case that autonomous cars should've been much more equipped to deal with, and the Uber clearly failed, it's not promising. Autonomous cars were supposed to be better than humans; this particular one does not seem to be, given that as a human I can pretty clearly see someone crossing from the far side of the road.

I am not the OP, but this numbers are not confirming the optimistic view that self driving cars are better, so if we do not have numbers that show that are better and even with a human driver inside we had a few incidents then the number without human driver inside would have been larger, so how should we determine that the self driving car X is ready to be released on public roads for testing? At least we should have some basic tests done by an impartial authority.
I'm not sure that's the point you want to make, an order of magnitude making Uber 2.5x more dangerous still.