Moonbear said:
Okay, I'm not seeing the logic here. I should try skydiving because less people die doing that than in car accidents?
Huh? No - you should try skydiving because it is
fun. I didn't mention that and was only addressing the main objection to skydiving (that it is dangerous).
What about other serious injuries?
Well fortunately, most other injuries from skydiving are minor. The error margin simply doesn't allow medium-to-serious inuries.
And, I'm still pretty certain the odds of being injured or dying from skydiving are MUCH higher if I actually jump from the plane than if I stay here with my feet firmly planted on the ground.
Certainly, but that is why I said most things in life involve risk. Your life would be far safer if you never got out of bed, but that isn't a good reason to do it.
By the way, that's a rather dubious comparison of statistics there. You're comparing the risk of dying per jump to the risk of dying in a car accident per person. Completely different methods of calculation.
No, I compared per person per year for both assuming an average driver and by calculating how many jumps you'd need per year to equalize the skydiving risk with the driving risk. I did normalize the skydiving stats as best I could, converting the per jump to per person per year given a certain jump frequency. Obviously, the driving stats depend on how much a person drives, but that's a tougher stat to use. All in all, I think the the way I compared them is a pretty fair way to do it.
Now, for car fatality statistics, the number of people getting into a car sometime in their lifetime is probably pretty close to the entire population, minus a few Amish perhaps. So, the 1 in 6500 people dying in car accidents is probably pretty close to the number of people getting into cars dying in car accidents. But, according to that first site you linked to, there are only about 25,000 active skydivers (I can't find a statistic for the number of people jumping in any given year to match to the number of fatalities), but in 2004 there were 24 skydiving fatalities in the US. That would put the risk a bit closer to 1 in 1000 skydivers dying in a giving year.
Yes, but aren't you making the mistake you were just pointing out to me above with cars? It depends on how many jumps you make. Ie, Odds per skydiver are only relevant if you are an average skydiver and there is a wide variation between the median and mean for skydivers: the vast majority of skydivers do it only
once.
If you're going to calculate the risk by number of jumps, rather than by number of jumpers, like in the site you linked to, then you'd need to calculate the number of car trips made in a year by each member of the population, not the number of people getting into cars anytime in the year.
If you calculate it that way, the risk would be much, much, much, much lower. At a bare minimum, most people get into a car at least twice a day to get to school or work or a store and then back home again, and of course there are people who make dozens of trips a day, shuttling kids back and forth to all sorts of activities, running errands to multiple locations, working as delivery drivers, etc.
No offense, Moonbear, but it seems like you are trying to argue your way out of a perfectly relevant statistic. Yeah, I certainly understand that your risk of dying per car trip is a lot lower than your risk of dying per skydive, but
that is comparing apples to oranges. It actually sounds to me a lot like the gambler's fallacy. If you wake up every morning and consider your odds of dying in a car accident
that day vs your odds of dying skydiving that day, you'll choose driving every day --- and end up far more more likely to die in a car accident because you haven't considered how driving
every day weighs into the odds.
And, well, there are also newborn infants who don't go much of anywhere in cars for a few months, other than the occassional check-up at the pediatrician's office.
Sure. Everyone is different, of course.
So, even if I made a very conservative calculation that everyone makes two car trips per day, that's 2 trips/person/day x 365 days/year = 730 car trips/person/year. Multiply that by the population (I'll stick with the population given for the year in your link that has the number of car fatalities). 291,000,000 people * 730 car trips/person/year = 212,430,000,000 car trips/year. NOW you can make a comparison to the number of skydives per year. 212,430,000,000 car trips/year divided by 45,000 car fatalities/year = 4,720,667 So, there's a risk of 1 fatality in 4,720,667 car trips per year. Far better than one fatality in 75,000 jumps, and I'm fairly confident that my estimate of car trips per day is an underestimate.
So if I make the same number of jumps as I do car trips in a year, those are my odds. How is that helpful if I only jump once a year, but I drive 730 times per year? See, if you ask yourself the risk every time you get into the car but don't ask yourself the risk again at the end of the year, you'll think you're being safer than you really are. Your odds of dying at a certain activity depend on how many times you do it!
Here: if all you are looking for are personalized numbers, here's something you can take to your odometer: the odds of dying per passenger mile in a car are .8 per hundred million. I drive about 15,000 miles per year, putting me at a yearly risk of dying of about 1 in 8,300. That's comparable to what I said above.
http://www.nsc.org/lrs/statfaq.htm
For my risk of dying skydiving, I didn't do it last year so my risk was zero, but the year I did it, there are two ways to calculate it: by person or by dive. Since I know how many times I dove (once), there is no reason to use the less accurate odds per skydiver, which assumes every skydiver is average. And for that, it was 1 in 75,000.
