5 ms·
Are you sure? If I drive once a day, to and from a single place, that suggests I’m involved in (365*2/100)= 7 car accidents a year. That seems high, no? Per a
by alwa 4y ago
Are you sure? If I drive once a day, to and from a single place, that suggests I’m involved in (365*2/100)= 7 car accidents a year. That seems high, no?
Per a quick glance at NHTSA’s summary figures [1] I wonder if the previous poster is referring to the “1000 injured per 100,000 drivers” figure. Which divides out to 1% I guess, a little more in past years. But that’s a little awkward to express in plain language, in that one wreck can injure lots of people, and people can get injured who are not drivers (drivers comprise around half of the injuries, it looks like, from higher up in the table).
Although the total number of crashes (including the large majority that don’t involve injuries) still looks pretty wild as a proportion of licensed drivers. If I were trying to raise concern about cars, I’d point to that ratio of 1 collision (of any sort) for every 43 licensed drivers every year.
[1] https://cdan.nhtsa.gov/tsftables/National%20Statistics.pdf https://cdan.nhtsa.gov/tsftables/National%20Statistics.pdf
- hedora 4y agoAssuming each collision involves two parties, 1 in 43 means about 1 in 21 people are driving during a collision each year. That seems about right. It’s one (probably minor) car accident per driver every 20 years.
- z2h-a6n 4y ago> Are you sure? If I drive once a day, to and from a single place, that suggests I’m involved in (365*2/100)= 7 car accidents a year. That seems high, no? That's partially because MonkeyClub didn't do the math correctly. If the accident rate is really 1% of trips (which seems doubtful), there is a 99% chance of an accident free trip, a (99%)^N chance of N accident free trips, and a 1 - (99%)^N chance of one or more accidents occurring in N trips. For N = 100, this is 63%, and for N = 365*2 this is 99.9%. As you mention, the data from the NHTSA seem to indicate a much lower accident/injury rate. Based on this data from the NHTSA [0], and going back to 2018 to avoid any pandemic-related effects on the statistics, it looks like there was on average only 1 (police-reported) crash per 481 thousand vehicle-miles, or one crash involving an injury or fatality per 1.7 million vehicle-miles. [0] https://cdan.nhtsa.gov/tsftables/National%20Statistics.pdf https://cdan.nhtsa.gov/tsftables/National%20Statistics.pdf, other formats and more data available here: https://cdan.nhtsa.gov/tsftables/tsfar.htm https://cdan.nhtsa.gov/tsftables/tsfar.htm
- MonkeyClub 4y ago> That's partially because MonkeyClub didn't do the math correctly. Or at all, since it’s just how possibilities work. I wasn’t calculating the annual possibility.
- z2h-a6n 4y ago> I wasn’t calculating the annual possibility. When I wrote: > For N = 100, this is 63%, ... I was responding to your comment: > It means that in out of a hundred trips, it’s pretty certain one will involve an accident. Whether or not 63% == 'pretty certain' is another matter I suppose.
- MonkeyClub 4y ago> Are you sure? Yep, totally. Remember the counter resets with every ride: it’s the first of the hundred, with 1% possibility of (any) car accident.