Comment by mbreese
5 hours ago
The more I think about your comment on statistics, the more I change my mind.
At first, I think you’re right - these are (thankfully) rare events. And because of this, the accident rate is Poisson distributed. At this low of a rate, it’s really hard to know what the true average is, so we do really need more time/miles to know how good/bad the Teslas are performing. I also suspect they are getting safer over time, but again… more data required. But, we do have the statistical models to work with these rare events.
But then I think about your comment about it only being 30 cars operating over 6 months. Which, makes sense, except for the fact that it’s not like having a fleet of individual drivers. These robotaxis should all be running the same software, so it’s statistically more like one person driving 500,000 miles. This is a lot of miles! I’ve been driving for over 30 years and I don’t think I’ve driven that many miles. This should be enough data for a comparison.
If we are comparing the Tesla accident rate to people in a consistent manner (accident classification), it’s a valid comparison. So, I think the way this works out is: given an accident rate of 1/500000, we could expect a human to have 9 accidents over the same miles with a probability of ~ 1 x 10^-6. (Never do live math on the internet, but I think this is about right).
Hopefully they will get better.
500,000 / 30 years is ~16,667mi/yr. While its a bit above the US average, its not incredibly so. Tons of normal commuters will have driven more than that many miles in 30 years.
That’s not quite the point. I’m a bit of an outlier, I don’t drive much daily, but make long trips fairly often. The point with focusing on 500,000 miles is that that should be enough of an observation period to be able to make some comparisons. The parent comment was making it seem like that was too low. Putting it into context of how much I’ve driven makes me think that 500,000 miles is enough to make a valid comparison.
But that's the thing, in many ways it is a pretty low number. Its less than the number of miles a single average US commuter will have driven in their working years. So in some ways its like trying to draw lifetime crash statistics but only looking at a single person in your study.
Its also kind of telling that despite supposedly having this tech ready to go for years they've only bothered rolling out a few cars which are still supervised. If this tech was really ready for prime time wouldn't they have driven more than 500,000mi in six months? If they were really confident in the safety of their systems, wouldn't they have expanded this greatly?
I mean, FFS, they don't even trust their own cars to be unsupervised in the Las Vegas Loop. An enclosed, well-lit, single-lane, private access loop and they can't even automate that reliably enough.
Waymo is already doing over 250,000 weekly trips.[0] The trips average ~4mi each. With those numbers, Waymo is doing 1 million miles a week. Every week, Waymo is doing twice as many miles unsupervised than Tesla's robotaxi has done supervised in six months.
[0] https://waymo.com/sustainability/