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# looking for statistics

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USPA has about 30,000 members.

There are about 30 fatalities a year.

So your chances of death are probably about 1 in 1000 from skydiving itself.

Ah, but here's another way to look at it: statistical risk of death on any given jump. I was under the impression that, in the US, there are roughly 3 million sport skydives made per year, and roughly 30-ish fatalities per year. So that would mean that on any given skydive made in the US, the statistical chance of death would be about 1 in 95,000, give or take. Big difference from 1 in 1,000.

That is why Statistics can be misleading.

On average per year in the US there is one fatality per 1000 USPA Members (but not all Fatalities in the US are USPA Members). There is on the order of 1 in 100,000 chance of a fatality on any given jump - all other factors being equal (which they are not - some people are at higher risk than others). If the average skydiver makes one hundred jumps in a season, their chances of dying is 1 in 1000, all other factors being equal (again they are not)

This brings to mind a first year University statistics courses I took too many years ago. One of the recommended texts was "How to Lie with Statistics" - not to encourage the practice but to appreciate how statistics could be manipulated and to question how the statistics were derived.

The only statistic I believe is that for every birth, there is one death. How you chose to use the time in between the two events is up to you.

Ten days till Eloy!

CSPA D-579

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Or as Mark Twain reminds us, "There are lies, damned lies and statistics."

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On average per year in the US there is one fatality per 1000 USPA Members (but not all Fatalities in the US are USPA Members). There is on the order of 1 in 100,000 chance of a fatality on any given jump - all other factors being equal (which they are not - some people are at higher risk than others). If the average skydiver makes one hundred jumps in a season, their chances of dying is 1 in 1000, all other factors being equal (again they are not)

But it can also be argued (proving Twain's point) that it's it's still 1/100,000. Example:
-1 coin toss - chance of heads - 1/2.
-Any given coin toss - chance of heads - 1/2.
-Suppose you toss a coin 99 times & get tails every single time. Chance that the next toss will be heads is (drumroll) 1/2.

Of course, your analysis assumes to take into account overall exposure to risk over the course of a given year. But does it? Does the 100 jump-per-year jumper have an overall chance of dying, sometime during that year, of 1/1000 or 1/100,000? Or something else?

I have no idea. I'm not a numbers nerd; I'm a word nerd. And now my head hurts.

Edited to change 1/1 to 1/2. I told you I'm not...

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I didn't want to haul out the Statistics Textbook to show the math as the risk factors for each person is different.

I remember hearing on a video a couple of years ago that "with todays equipment, training, and the proper respect for the situation... Skydiving can be very safe... However if you want to make it dangerous, you can do that too"

Canopy selection is an example. How many fatalies are caused by big student type canopies? However most are "bored" with the "performance" of student canopies and downsize to smaller canopies.

A 100 jump wonder on a pocket rocket loaded at 2.0 has a different risk factor than one jumping a conservative canopy loaded at 0.9.

Darwin loves 100 jump wonders

CSPA D-579

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Of course, your analysis assumes to take into account overall exposure to risk over the course of a given year. But does it? Does the 100 jump-per-year jumper have an overall chance of dying, sometime during that year, of 1/1000 or 1/100,000? Or something else?
I have no idea. I'm not a numbers nerd; I'm a word nerd. And now my head hurts.

For a word person, you're doing great, but make that a 1/2 chance. Statistics/probability is governed by the law of large numbers. It really isn't an individual's chance of doing something, but rather if the activity happens a sufficiently large number of times, then # out of n times, you can expect to have a certain result.
"safety first... and What the hell.....
safety second, Too!!! " ~~jmy

POPS #10490

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yes, deffinetly a matter of number of jumps, not number of members
"he knows what its like to be dieing, so he knows what its like to live"

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As MajorDad has alluded to, it also has a lot to do with the personal decisions a jumper is making. For example, I think about half of USPA's fatalities last year were swoopers impacting with the ground under a fully-functioning canopy. So if you're not a swooper, you can take those fatalities out of whatever statistics equation you're using.
What it really comes down to is risk management. There is, of course, always a chance that both of your parachutes will fail to do their jobs correctly and you'll end up dead because of it. However, this is an extremely rare occurance. Most of the skydiving deaths each year could be prevented by choices made by the individual skydiver. Do they know how to properly execute emergency procedures for each possible scenario? Do they properly maintain and inspect their gear? Do they know how to keep seperation between themselves and others, both in freefall and under canopy? Are they flying a canopy suitable for their skill level? Are they flying that canopy in a manner suitable for their skill level? Etc.
If you really want to impress your parents, I'd suggest finding out what possible issues you could have while skydiving and finding out what can be done to prevent or deal with those issues, thereby mitigating the risk.

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I hate statistics. Statistics on paper wouldn't even be used to wipe my arse.

Too many variables to consider, we each have a different chance of death from skydiving

Even if i do 500 jumps a year and my friend does 500. We all have different reaction times and react differently when in stressful situations.

If he's pullin at 2k every jump, trashpacking and flying a napkin sized canopy he's exposed to more risk.

Bottom line is statistics will tell you anything you want them to say. Fool your parents but dont fool yourself into thinking its "safer than driving"
1338

People aint made of nothin' but water and shit.

Until morale improves, the beatings will continue.

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Don't bother. You will NEVER convince them that is even remotely a safe thing to do. They believe it si dangerous and foolhardy. Once a person believes something, no amount of fact, truth or data will convince them otherwise. Just ask any religious person. Go, make your jump(s) and just don't talk about it to them.
Skydivers don't knock on Death's door. They ring the bell and runaway... It really pisses him off.
-The World Famous Tink. (I never heard of you either!!)
AA #2069 ASA#33 POPS#8808 Swooo 1717

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Why do you have to call me out like that Andy? What did I ever do to you.

Still mad because I dump lower than you and my canopy was 1/2 the size of yours.

SONIC WOODY #146

There is a fine line between cockiness and confidence -- which side of the line are you on?

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A follow up. I once calculated the fatality rate in skydiving as 1 in 225,00. (Data set was from 1999) Compared to the fatality rate for treadmills at 1 in 10,000. It didn't convince a single person outside of the review board.
Skydivers don't knock on Death's door. They ring the bell and runaway... It really pisses him off.
-The World Famous Tink. (I never heard of you either!!)
AA #2069 ASA#33 POPS#8808 Swooo 1717

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Now come on Billy. Its not my fault you lost altitude awareness

1338

People aint made of nothin' but water and shit.

Until morale improves, the beatings will continue.

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I knew I wasnt on the ground yet, so technically I didnt lose awareness. I had plenty.

SONIC WOODY #146

There is a fine line between cockiness and confidence -- which side of the line are you on?

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Ah, but here's another way to look at it: statistical risk of death on any given jump. I was under the impression that, in the US, there are roughly 3 million sport skydives made per year, and roughly 30-ish fatalities per year. So that would mean that on any given skydive made in the US, the statistical chance of death would be about 1 in 95,000, give or take. Big difference from 1 in 1,000.

an effective (and valid) argument if you're going to do a tandem, but not if you intend to enter the sport.

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Very interesting responds that I didn’t expect.

I come from very conservative society, Saudi Arabia; I am here in the US primarily for education. I picked up this sport last July. I haven’t had one week since then without making at least one jump before I broke my ankle. I am very close to my parents and I have informed both about my interest in the sport. They were actually very supportive. I speak to them on weekly basis; my mother, especially, always ask me about skydiving and how many jumps I have made recently. I severely ruptured/broke my ankle (along with a few bones in that same leg) on my 44th jump due to hard landing as I downsized to be under 1.2 WL. My father reaction to this was telling me a story about his friend who broke his knee into several fragments from falling while going down on the stairs.

My father even offered helping me with buying my own canopy after I recover from the injury. GO DAD!

I personally think that the most important thing is the way you approach your parents.

Have fun skydiving

Amer
"Those who would give up Essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety" Franklin

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on my 44th jump due to hard landing as I downsized to be under 1.2 WL.

...which brings up a whole new subject...

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One more thing. You're falling victim to the instinct you still have to (a) tell your parents what you're doing, (b) get your parents' blessing for something you're doing. Those are your chains. It's quite liberating to come to the realization that you need to do neither.

______________________________________________

That's true. I once made the mistake of telling my parents that while I attended a seminar for work in the big smoke, I would be taking my rig along and jumping a building that night. I was excited and looking forward to it. I had well over 1000 skydives at the time so to me it wasn't a big deal, I just mentioned it in passing.

My dad later told me that my mother didn't sleep that night, so after that I never told them anything I was thinking of doing.

Ignorance is bliss.
If some old guy can do it then obviously it can't be very extreme. Otherwise he'd already be dead.
Bruce McConkey 'I thought we were gonna die, and I couldn't think of anyone

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I just turned 18 in June and was in the process of finding a new job and once i did i started my AFF...My parents have known for a long time that it was going to happen i've been talkin about it sense i was little....But i say just talk them into it if its something you wanna do. And look forward to your first jump its was an experience that will be hard to beat!!!
What would you attempt to do if you knew you would not fail...

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i say just talk them into it if its something you wanna do.

Yeah, that's it; just talk them into it. Why didn't I think of that?

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Every so often the discussion of statistical probability of dying in skydiving comes up and the same discussion ensues... skydiving vs. driving, skydiving vs. bike riding, skydiving vs. rock climbing, vs. taking a bath, etc. Usually followed with the sub-debate of number of skydives in the U.S. vs. hours on the road, vs, number of members, vs. hours on a bike, etc.

I understand and used to engage in these discussions myself, but over time have come to the conclusion that we as skydivers are doing those who try to categorize statistical segments into blocks a disservice. We; as a group tend to communicate:

Skydiving | Driving | Rock Climbing | Bath | Motorcycle | Bicycle |...

In reality, it's:

Skydiving + Driving + Rock Climbing + Bath + Motorcycle + Bicycle +... for a cumulative probability of just making it thru the day.

While observing Texas Hold'em Championships, I noticed they showed the players' cards pre-flop and the statistical probability of which hands would win the round pre-flop. For example, A/A is 87.65% to win. When in actuality, any two cards (ATC) have the exact same probabilty to win pre-flop. Now, holding the 7/6 against A/A has a greater risk of losing, but averting or capitalizing on that risk comes by _experiencing_ the flop.

The same is true in life. Every morning we wake up, we all have the exact same probability of living or dying thru the day. Mere geography factors into that risk. As pointed out, capitalizing or averting that risk (driving + two beers will increase the factor of risk, but there's always the other guy whose driving + two beers which gives one the exact same probablity of being in an alcohol-related accident).

Each time someone gets in a car, that individual has the exact same probability of living or dying. The only way to completely avert the risk of dying in a car wreck is to not get in a car. But, in doing so, we never go anywhere, we never see anything and as a result, never get to _experience_ anything. The wonders of Yellowstone, the Rocky Mountains, the desert, etc.

The point of this discussion is this - There are those in skydiving with thousands of jumps who've had zero injuries or no malfunctions, etc. who have the exact same probability of dying each jump as those who have one or a hundred jumps. From a pure statistical persepective; each time we jump, every skydiver... all have the exact same probability of living or dying. We have a saying, "You can do everything right and still die." I have watched situations where one has done everything wrong and still lived and seen those who are some of the safest skydivers do everything right and die.

One can choose not to skydive and in doing so; not have the opportunity to _experience_ the wonders of what we get to feel, see, smell, hear. Even if it's just one time.

We also have another saying in skydiving - "It has to be a personal choice." It really HAS to be. Your choice cannot be based on statistical probability. No skydiver or statistician can tell you the probability of your living or dying if you jump.

There is a 100% probability that we are all going to die - sometime, someway, somehow; even if it's just from old age. The real statistical question is - What is the probability of living life 100%.

How is that for combining statistics and philosophy first thing in the morning?

Nobody has time to listen; because they're desperately chasing the need of being heard.

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A jumper makes on average 100 jumps / year (3M jumps for 30,000 members). So the probability expressed in # of jumpers and in # of jumps seem in fact consistent (1 every 1000 jumpers or 1 every 100,000 jumps). The average risk is the same, the unit is just different.

Rather than considering that the risk is the same regardless of what jumpers are doing, I still think that :
1) the risks we take during a jump are for most part based on the choices we make,
2) certain situations increase the risks so it is the jumpers responsibility to recognize that, be even more careful when that happens and develop the skills to minimize those risks.
Laurent - www.RhythmSkydiving.com

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Illusion of control.
Nobody has time to listen; because they're desperately chasing the need of being heard.

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Wow BIGUN. Best reply I have ever seen in regards to this question, hands down. Nice work.

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Thanks. I have my moments... it's just that being half brilliant and half full of shit; you have to decide which moment I'm in.

Nobody has time to listen; because they're desperately chasing the need of being heard.

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Well I agree on one thing at least is that thinking you can control all the risks is illusion. But you cannot seriously say that jumpers have no more control on the outcome of a skydive compared to rolling a pair of dices. Yourself (Bigun) recently considered that 145 jumps and 2.45 wing loading is probably madness. It puts the jumper and others at additional risks. It's just common sense and you were right. Someone with no training at all wouldn't survive a skydive at the first place. Poor decisions and poor training do increase the risks for everybody, and this can be more significant that the risks we can't manage. So I think we can agree that part of the risk is in fact manageable by making reasonable choices. It's the jumpers responsibility.
Laurent - www.RhythmSkydiving.com

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