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NHTSA Tells Tesla To Stop Exaggerating Model S Safety Rating
cartechboy writes "There's always that kid in the class that ruins it for everyone when being graded on a curve. At the moment, that kid is Tesla and Elon Musk. Tesla's been proudly claiming the Model S is one of the safest cars in the word despite the recent fire controversy. And while it may be just that, claiming it earned 5.4 stars from NHTSA isn't pleasing the safety agency as there is no such thing as a rating higher than five. While NHTSA already released a statement indirectly to Tesla saying it doesn't release ratings higher than 5, Tesla continued to promote this fictitious rating. Now NHTSA has updated its guidelines explicitly stating safety ratings are whole numbers only and that 5 stars is the maximum advertisers can claim. If advertisers and automakers decide to disregard these rules NHTSA is threatening removal from the program or referral to state authorities for appropriate action. Basically, hey Tesla, stop making false claims."
It got a 5.4 rating, but the NHTSA guidelines only allow them to advertise a whole number.
Just to clarify, the NHTSA hasn't said anything to Tesla like the summary states. It has clarified its rating system. That is all.
That article is written like a high schooler's blog.
I think we've seen this before...
Would still only result in whole numbers, assuming nhtsa_rating is some form of uint.
Yep. The NHTSA apparently gives the manufacturers the individual ratings in each category, which presumably go above 5 and may be decimal. They may have some sort of agreement that they aren't allowed to publish the individual ratings.
From Tesla's website, the actual claim:
NHTSA does not publish a star rating above 5, however safety levels better than 5 stars are captured in the overall Vehicle Safety Score (VSS) provided to manufacturers, where the Model S achieved a new combined record of 5.4 stars
--Source
I can understand the NHTSA complaint (Tesla's claims could be misleading out of context), but its not like Tesla is making any false claims.
Also, I recall this claim / story being about 3 months old at this point, and I believe NHTSA complained around the same time. Is slashdot seriously that far behind, or (as I suspect) is this an attempt to generate additional controversy and angst due to the other Tesla stories in the news?
Not really.
What happens is cars are rated to the current safety rating - the reason you can score above 5 is because the number is based on the raw figures and the current weightings.
The NHTSA records down in its database the raw numbers, then uses those numbers to calculate the safety rating based on the current weightings (from empirical data). This lets them recalculate the safety rating as need be - yesteryear's 5 stars may be this year's 3 stars, for example. Or, depending on how cars individually perform, it's possible two 5 star cars with the old rating may become a 3-star and a 4-star car.
So you cannot compare "stars" between model years, but you can compare them with historical vehicles recalculated to new standards. After all, many old 5 star vehicles may lack the safety features present on today's modern vehicles, so they won't be 5 stars anymore in the current rating.
The rating will go down as new model years and new tests are introduced - after all, we'd have hit 5 stars 50 years ago if the tests didn't change. The NHTSA updates its tests and ratings when too many cars are pegged - and there's a new test that apparently reflect the more common crashes that many "5 star" cars now fare poorly on.
Next year, the 2013 Tesla Model S may drop from 5.4 to 4.3. But the 2014 Tesla Model S may still get a full 5 stars because Tesla anticipated the new tests and built the cars to withstand them appropriately.
No, he's not correct. If he wants to go into more detail about safety than the NHTSA does, or make claims on his own, that's fine.
They are correct, you are wrong.
"NHTSA does not publish a star rating above 5, however safety levels better than 5 stars are captured in the overall Vehicle Safety Score (VSS) provided to manufacturers, where the Model S achieved a new combined record of 5.4 stars."
The NHTSA is pissed because you're not supposed to TELL people what the ACTUAL safety rating is.
For example, the Tesla's VSS works out to 5.4 stars prior to rounding, another car has 4.5 stars prior to rounding. Despite being almost an entire "star" apart, both these vehicles get "5 stars" and appear to be just as safe to the consumer. The NHTSA is pissed because they don't want the public to be aware of it, because people will rightfully ignore the star ratings and demand the raw VSS instead. And that would show many cars are a lot worse in comparison than the Star System reveals... and the people who are invested in those companies pend a LOT of money on political donations.
It's ALSO important to note that even the NHTSA admits they don't even consider many of the more advanced safety systems in their calculations at all.