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> Don't tell us how safe Tesla's are compared to the entire US driving population: Tell us how safe they are compared to equivalent vehicles from other manufact

> Don't tell us how safe Tesla's are compared to the entire US driving population: Tell us how safe they are compared to equivalent vehicles from other manufacturers. I'm having a hard time to find an exact number comparison, but: - Tesla claims 1 fatality per 320M miles Compared to - A 2015 study of 2011 model year vehicles showed, for instance, Volvo XC90 had never been involved in a driver fatality (1) - There are about 10K 2011 XC90s in the US (2) - Avg. US drivers cover 13,400miles / year (3) So: - 4 years studied * 10K vehicles * 13,400 avg miles -> 536,000,000 fatality-free miles This is obviously super hand-wavy, but I think it's fair to state as a hypothesis that Tesla could be twice as deadly as the safest high-end vehicles.. you'd need to design some experiment to attempt to falsify it to feel confident this is correct. (1) https://www.freep.com/story/news/nation/2015/01/29/study-chances-of-dying-in-a-car-crash-plunged-over-3-years/22521103/ https://www.freep.com/story/news/nation/2015/01/29/study-cha... (2) http://carsalesbase.com/us-car-sales-data/volvo/volvo-xc90/ http://carsalesbase.com/us-car-sales-data/volvo/volvo-xc90/ (3) https://www.fool.com/investing/general/2015/01/25/the-average-american-drives-this-much-each-year-ho.aspx https://www.fool.com/investing/general/2015/01/25/the-averag...

lettergram 9y ago
Probably should also note, that the average Tesla driver is likely male, has money (i.e. more risk taking), etc. Essentially, compare to sports cars as opposed to high end vehicles. They we're originally advertised as sports cars really. 0 to 60 faster than any other car, etc.
aoeusnth1 9y ago
Eh, you can't cherry pick specific (model, year) combinations after the fact without overfitting. You expect some variation in deaths per (model, year) and by searching for the least deadly ones, you'll dramatically influence your estimate simply because you used a maximizing search instead of a broad survey of a-priori safe models.
- jakewins 9y ago
  This is totally true, and I agree; I tried to guard against this at the end with the "I think this is enough to state a hypothesis, which would then need to be tested.." paragraph. However - the same is true for 2009, 2010, 2011, 2012 model XC90s, and they are just one of 10 models that had no fatalities in those four model years in the study. I just picked that year and model to get one data point for mileage to compare; the other model years of XC90 have similar sales, so the same applies. So, while you're right, I don't think it's an entirely useless comparison; it indicates there could be something here, which could then be used to state a falsifiable hypothesis, something like: "Similar cohort drivers would be safer in <one of these ten models> than in a Tesla.".
  - emn13 9y ago
    At a minimum it indicates that Tesla's numbers do not seem exceptionally safe, even if you can't say they're less safe than comparable competitors either. Given the low number of incidents, you probably want to be looking at something other that fatalities to get a large enough pool of incidents to reduce the impact pure chance; at least in addition to actual fatalities. It's not going to be an easy comparison, that's for sure.
ams6110 9y ago
I'm not sure how much of that is about the car versus the driver. Volvo drivers are some of the most slow, excessively cautious, annoying (to others) drivers on the road.

lettergram 9y ago

Probably should also note, that the average Tesla driver is likely male, has money (i.e. more risk taking), etc. Essentially, compare to sports cars as opposed to high end vehicles. They we're originally advertised as sports cars really. 0 to 60 faster than any other car, etc.

aoeusnth1 9y ago

Eh, you can't cherry pick specific (model, year) combinations after the fact without overfitting. You expect some variation in deaths per (model, year) and by searching for the least deadly ones, you'll dramatically influence your estimate simply because you used a maximizing search instead of a broad survey of a-priori safe models.

jakewins 9y ago
This is totally true, and I agree; I tried to guard against this at the end with the "I think this is enough to state a hypothesis, which would then need to be tested.." paragraph. However - the same is true for 2009, 2010, 2011, 2012 model XC90s, and they are just one of 10 models that had no fatalities in those four model years in the study. I just picked that year and model to get one data point for mileage to compare; the other model years of XC90 have similar sales, so the same applies. So, while you're right, I don't think it's an entirely useless comparison; it indicates there could be something here, which could then be used to state a falsifiable hypothesis, something like: "Similar cohort drivers would be safer in <one of these ten models> than in a Tesla.".
- emn13 9y ago
  At a minimum it indicates that Tesla's numbers do not seem exceptionally safe, even if you can't say they're less safe than comparable competitors either. Given the low number of incidents, you probably want to be looking at something other that fatalities to get a large enough pool of incidents to reduce the impact pure chance; at least in addition to actual fatalities. It's not going to be an easy comparison, that's for sure.

ams6110 9y ago

I'm not sure how much of that is about the car versus the driver. Volvo drivers are some of the most slow, excessively cautious, annoying (to others) drivers on the road.