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Tesla’s Driver Fatality Rate is more than Triple that of Luxury Cars

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Re: Tesla’s Driver Fatality Rate is more than Triple that of Luxury Cars

#11

Post by rgbrenner »

dahdum wrote: post #8
rgbrenner wrote: post #7

Earlier quoted context omitted.

Rigorous? lol. I'm usually slightly critical of tesla.. but this article is terrible. It's so long because the author needs to jump through too many hoops to end up where he wants to go. Audi A6 has 0 causalities? Cool. Tesla has 0 in one year? Extremely suspicious. Not enough Tesla accidents in the database? Include China. Should he include China for the other cars? Nah. This article is a joke.

The firm is short Tesla, but I’d still like to see a data driven Tesla rebuttal before believing it’s all smoke and no fire.

The data is in the article. They didn't like the conclusion, so then they included China, did a google search for tesla accidents, and made adjustments--only to tesla--until they got what they wanted. They aren't even comparing like with like... all of the conclusions are invalid.

I don't think this article was written in good faith.

Re: Tesla’s Driver Fatality Rate is more than Triple that of Luxury Cars

#12

Post by dahdum »

rgbrenner wrote: post #11
dahdum wrote: post #8

Earlier quoted context omitted.

The firm is short Tesla, but I’d still like to see a data driven Tesla rebuttal before believing it’s all smoke and no fire.

The data is in the article. They didn't like the conclusion, so then they included China, did a google search for tesla accidents, and made adjustments--only to tesla--until they got what they wanted. They aren't even comparing like with like... all of the conclusions are invalid. I don't think this article was written in good faith.

They found clear Tesla fatalities that were missing from the published data, apparently a significant number of them due to miscategorization.

Now maybe all the brands have the same problem with missing data, but that would mean fatalities across the board are much higher than reported by the insurance agency funded research firm. That doesn’t seem as likely to me, but I do believe more research needs to be done.

Re: Tesla’s Driver Fatality Rate is more than Triple that of Luxury Cars

#13

Post by rgbrenner »

dahdum wrote: post #12
rgbrenner wrote: post #11

Earlier quoted context omitted.

The data is in the article. They didn't like the conclusion, so then they included China, did a google search for tesla accidents, and made adjustments--only to tesla--until they got what they wanted. They aren't even comparing like with like... all of the conclusions are invalid. I don't think this article was written in good faith.

They found clear Tesla fatalities that were missing from the published data, apparently a significant number of them due to miscategorization. Now maybe all the brands have the same problem with missing data, but that would mean fatalities across the board are much higher than reported by the insurance agency funded research firm. That doesn’t seem as likely to me, but I do believe more research needs to be done.

And then they still didn't like the numbers for the US, so they included China--for tesla only. Do you know how much that changes the numbers?

The US had 12.9 fatalities per 100k cars. China? 104.5 -- 8 times higher.

Come on. This is a joke.

Re: Tesla’s Driver Fatality Rate is more than Triple that of Luxury Cars

#14

Post by wjnc »

et2o wrote: post #5

Is this really what passes for statistical analysis in the investment community? From a biomedical statistics background, this analysis so atrocious that I don't know where to start.

So please explain. It's quite a long story but with some good finds (data quality problems, obfuscated reporting, probability of much higher casualty rate). I wonder what your statistical rigour makes of this.

Re: Tesla’s Driver Fatality Rate is more than Triple that of Luxury Cars

#15

Post by f00_ »

et2o wrote: post #5

Is this really what passes for statistical analysis in the investment community? From a biomedical statistics background, this analysis so atrocious that I don't know where to start.

maybe some censored data problems here? I'm interested in seeing a jupyter notebook analysis on driver fatality rates

Does anyone have experience doing survival analysis? I've read a lot of the documentation of CamDavidsonPilon's Lifetimes. maybe i'll give it a shot, seems like the type of thing people would already do to price car insurance

Tesla’s mortality rate (41 deaths per million vehicle years) is so much higher than the average luxury car (13 deaths per million vehicle years) that when comparing the two, the difference is hugely statistically significant. The difference is 28 additional deaths per million vehicle years, with a confidence interval of 11 to 63, and a p-value of 0.0001.

Binomial confidence intervals for individual cars except Tesla provided by IIHS

Binomial confidence intervals for Tesla and groups using Conflint.xls from John Pezzullo

so he is doing some kind of hypothesis testing, using the binomial distribution but I wish he would post the data and spreadsheets used to generate everything. probably some p-hacking going on?

I'm not really that statistically literate, just a computer engineering dropout if someone could explain that'd be cool

Re: Tesla’s Driver Fatality Rate is more than Triple that of Luxury Cars

#17

Post by rgbrenner »

f00_ wrote: post #15
et2o wrote: post #5

Is this really what passes for statistical analysis in the investment community? From a biomedical statistics background, this analysis so atrocious that I don't know where to start.

maybe some censored data problems here? I'm interested in seeing a jupyter notebook analysis on driver fatality rates Does anyone have experience doing survival analysis? I've read a lot of the documentation of CamDavidsonPilon's Lifetimes. maybe i'll give it a shot, seems like the type of thing people would already do to price car insurance Tesla’s mortality rate (41 deaths per million vehicle years) is so much high…

China's fatality rate is 8x higher than the US. The author only included it for Tesla.

The author then went on google and tried to find more articles. Included whatever he could find only for Tesla.

If you're going to go through extra steps to pump Tesla's numbers, then of course they're going to be higher.

Duh.

Re: Tesla’s Driver Fatality Rate is more than Triple that of Luxury Cars

#18

Post by ajross »

dahdum wrote: post #12
rgbrenner wrote: post #11

Earlier quoted context omitted.

The data is in the article. They didn't like the conclusion, so then they included China, did a google search for tesla accidents, and made adjustments--only to tesla--until they got what they wanted. They aren't even comparing like with like... all of the conclusions are invalid. I don't think this article was written in good faith.

They found clear Tesla fatalities that were missing from the published data, apparently a significant number of them due to miscategorization. Now maybe all the brands have the same problem with missing data, but that would mean fatalities across the board are much higher than reported by the insurance agency funded research firm. That doesn’t seem as likely to me, but I do believe more research needs to be done.

> They found clear Tesla fatalities that were missing from the published data

They looked for Tesla fatalities because they needed more to make the argument they wanted. You understand the distinction, right?

Re: Tesla’s Driver Fatality Rate is more than Triple that of Luxury Cars

#19

Post by google_censors »

wjnc wrote: post #14
et2o wrote: post #5

Is this really what passes for statistical analysis in the investment community? From a biomedical statistics background, this analysis so atrocious that I don't know where to start.

So please explain. It's quite a long story but with some good finds (data quality problems, obfuscated reporting, probability of much higher casualty rate). I wonder what your statistical rigour makes of this.

Well, including data from China for only Tesla is a joke. That would be like saying "we couldn't find any deaths from Ebola in the United States, so we took the ones in Africa and added them in. Wow, look at how many deaths per year from Ebola occurred in the US compared to deaths from the plague in the US!". It makes absolutely no sense.

Re: Tesla’s Driver Fatality Rate is more than Triple that of Luxury Cars

#20

Post by dahdum »

ajross wrote: post #18
dahdum wrote: post #12

Earlier quoted context omitted.

They found clear Tesla fatalities that were missing from the published data, apparently a significant number of them due to miscategorization. Now maybe all the brands have the same problem with missing data, but that would mean fatalities across the board are much higher than reported by the insurance agency funded research firm. That doesn’t seem as likely to me, but I do believe more research needs to be done.

> They found clear Tesla fatalities that were missing from the published data They looked for Tesla fatalities because they needed more to make the argument they wanted. You understand the distinction, right?

Yes, they are obviously biased and openly so, but they've raised what appear to be valid points that Tesla should answer. Elon made the claim publicly, and Tesla is no stranger to writing snatching rebuttals.

As disclosure, I'm long TSLA, both index and individual shares.

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