kallend 2,114 #26 February 18, 2005 Ron, nowhere have I objected to more training. I'm pleased and grateful that mjo has found and posted these data - it makes identifying the most at-risk group and figuring out a workable solution easier whern you know what's going on. I am surprised that USPA, which has access to lots more information on the demographics of skydivers, hasn't come up with a comprehensive analysis.... The only sure way to survive a canopy collision is not to have one. Quote Share this post Link to post Share on other sites
Ron 10 #27 February 18, 2005 Quote Ron, nowhere have I objected to more training. I'm pleased and grateful that mjo has found and posted these data - it makes identifying the most at-risk group and figuring out a workable solution easier whern you know what's going on. I never said you were...However, I don't see how knowing that the age group is 26-35 and male helps with making a better training program. Everyone would benefit by more knowledge. And thats why I always had a test out for those who could prove it."No free man shall ever be debarred the use of arms." -- Thomas Jefferson, Thomas Jefferson Papers, 334 Quote Share this post Link to post Share on other sites
mjosparky 4 #28 February 18, 2005 Quote Quote Ron, nowhere have I objected to more training. I'm pleased and grateful that mjo has found and posted these data - it makes identifying the most at-risk group and figuring out a workable solution easier whern you know what's going on. I never said you were...However, I don't see how knowing that the age group is 26-35 and male helps with making a better training program. Everyone would benefit by more knowledge. And thats why I always had a test out for those who could prove it. I agree with Ron. If you have less then 250 jumps and screw your 1.6/1 canopy into the ground, you sex or age mean nothing. Your lack of knowledge and experience does. SparkyMy idea of a fair fight is clubbing baby seals Quote Share this post Link to post Share on other sites
dorbie 0 #29 February 18, 2005 Quote Quote It also shows how you can sometimes use statistics to pull out a metric that supports any position you like. What this shows is that since 12/14/1995, 112 people died under good canopies in the US. That statistic supports one thing, that is way to many people dead. Now pull a "metric" out of that and support any damn thing you want. 112 PEOPLE DEAD UNDER A GOOD CANOPY. Sparky Stating the obvious gets us nowhere. It's just wildly inappropriate to get all hot & bothered about asking for population information and jump numbers to be factored in. Why anyone would object to this is beyond me. It's the absolute minimum requirement before drawing meaningful conclusions backed by data. P.S. w.r.t. statistics supporting multiple positions, that would really refer to my suggestion of factoring in jumps per fatality (This is NOT the total jumps of the individuals involved in the incidents, these things are very different), and what it means when you consider the overall risk to a jumper vs the risk per jump. You can easily see that someone who does a lot of jumps adopts proportionately greater risk and this might offset experience unless you factor in jumps per fatality in a population segment. That is specifically why I suggested that normalization and why you might draw multiple conclusions from the same data. One would be a risk per jumper(per year presumably) (as Kallend initially requested) and the other would be a risk per jump, the results could (would IMHO) look very different and support different conclusions. Quote Share this post Link to post Share on other sites
chrisgr 0 #30 February 18, 2005 The population that is important in this case is the 112 skydivers who had properly functioning canopies and are now dead. What difference does it make if they were young/old, male/female, green/purple, etc. They were all skydivers who had properly functioning canopies and are now dead. Will your statistical analysis of this data result in any action that will help prevent future injuries or deaths? Quote Share this post Link to post Share on other sites
dorbie 0 #31 February 18, 2005 Quote The population that is important in this case is the 112 skydivers who had properly functioning canopies and are now dead. What difference does it make if they were young/old, male/female, green/purple, etc. They were all skydivers who had properly functioning canopies and are now dead. Will your statistical analysis of this data result in any action that will help prevent future injuries or deaths? You don't understand what I mean by population information. I'm not talking about census data or anything as irrelevant. In the absence of action we'll be better informed about the risks we take, that alone is justification enough for me. If there is action it could help make it the right action, that's the whole point. If you just want to contemplate a tragic total and learn the minimum from it, or worse take the wrong lesson away, then no. What risk factors/indicators were involved? That's why the initial attempt was made to break this down by category. If I know this is flawed then I have a responsibility to point it out. Simply breaking down the totals by age or jumps is utterly meaningless without at least the information Kallend asked for and the additional information I suggested be used. If you don't understand what I've written then move on or try to learn a bit about statistics but don't blame the messenger. Quote Share this post Link to post Share on other sites
kelpdiver 2 #32 February 18, 2005 Quote The population that is important in this case is the 112 skydivers who had properly functioning canopies and are now dead. What difference does it make if they were young/old, male/female, green/purple, etc. They were all skydivers who had properly functioning canopies and are now dead. Will your statistical analysis of this data result in any action that will help prevent future injuries or deaths? It certainly could. Take motorcyclists. Looking at accident rates, it's quite clear that young riders (or drivers) get in a lot more accidents than the general population. California responded to that by making the MSF riders course mandatory for those under 21 (and reducing the cost in half). I think that has done a lot more for fatality numbers than the lid law. In the past month, I read that biking deaths for those over 40 (maybe 50?) has gone up dramatically over the past decade. Is it a new problem? Unlikely - the average age of a motorcycle owner has gone up several years, so now there are simply more riders in that age bracket. So it's less productive to target that age group in particular, effort is better spent on the entire population. We already have BSR threads, and no where in Sparky's first posting was that linked in. The posting was an analysis of the landing incidents, so of course it matters who were in the various categories. Ideally you would want to know how many jumpers are in each age cohort, and how many jumps they did. This information is collected by the USPA on the renewal form - it's self reported, but should be of reasonable quality to do this kind of analysis. Quote Share this post Link to post Share on other sites
dorbie 0 #33 February 18, 2005 Quote ........, so of course it matters who were in the various categories. Actually it matters critically how many were in each category, "the population". I'm less concerned about things like age but maybe it needs to be looked at, we have the data so why not (it's actually fraught with pitfalls generalizations). However Kallend was absolutely right when he said a useful analysis is impossible without at least the total number of jumpers per category, and IMHO the jumps per category in whatever form you can get it. Quote Share this post Link to post Share on other sites
crewkeith 0 #34 February 19, 2005 i sat and wrote a nice three page essay about what is wrong with the skygods and the newbies but who would care???????? its past me i guess. on to commercialization if you wanna know, pay someone. that's what its' come to right????? to everyone, pay the money get a pro to teach you 'cause the shit you get for asking a question here isn't worth it thanks for all your help, skygods .The skies are no longer safe I'm back Quote Share this post Link to post Share on other sites
airtwardo 7 #35 February 19, 2005 Quote Somebody call me? Quote ...And on a lighter note~ Nice BOOTS! ~ If you choke a Smurf, what color does it turn? ~ Quote Share this post Link to post Share on other sites
Liemberg 0 #36 February 19, 2005 Quote I am posting this for information only, not for debate. "Poisson - my first love!" Although I'm sure that John Kallend can explain this stuff a lot better than I can, I have a few remarks if I'm allowed... Who was Poisson and why is what he said significant for statistical analysis of skydiving fatalities? Poisson was a mathematician who worked for the Prussian army. That army had a lot of horses. The horses were kept in stables, people had to remove the manure and sometimes a nervous horse would kick - killing a Prussian stableman. This (being kicked to death by a horse while removing manure from its stable) was a rare event, yet removing the manure wasn't. If you worked in the stable, that is what you would do, most of the day - clean the stable. What Poisson was interested in was the apparent 'randomness' of this event and more specific a 'test for randomness' for rare events in large populations. Something like: Almost twice a day, behind every horse in the stables of the Prussian army, a stableman appears to remove the manure. A few times per year a stableman is killed by a kick of one of these horses. Now do they kick 'at random' (one would think they would) or do they kick more often on certain occasions (Horse extra grumpy in the morning? Horse more likely to kick when stableman smokes a pipe with particular brand of tobacco?). From there maybe you could derive some 'standing field-order number 19' that could read 'Do not remove manure in the first two hours of the day' or 'do not remove manure while smoking a pipe...' I honestly don't know if the Prussian army actually reduced the number of deaths in the stables thanks to Poisson's work - but it gave US the Poisson distribution of rare events. If anyone wants to say anything that rises above the obligatory 'opinion' (yes - we all produce manure...), he needs to know the percentages in the different age- and experience-groups for all the skydivers where the 'rare events of someone screwing himself into the ground' are derived from. The 'original distribution' of age- and experience should be known and the 'score' should be known. The 'original distribution' gives us an expectation - something like "on the planet Tralmafadoria that is in every aspect a lot like the planet earth, people jump out of airplanes for the fun of it. We expect one in ninetythousand tralmafadorian skydives to end up in a fatality and one in three tralmafadorian skydiving fatalities should involve a perfectly open parachute. We do allow for a certain spread-around-our-expectation due to the random nature, built into the events..." The score is what it is - and from there you could go back to the expectation and say things like: "Indeed, we shouldn't give them hot-rod parachutes to them inexperienced youngsters, they are far more likely to kill themselves with it than 'average skydivers' would..." or - if the score dictates it - "don't stand in the way of so much young swoopers talent, what do YOU know about modern parachute's - you learned on rounds!" Since I don't see reliable statistical data that allows for a 'Poisson-analysis' appear in the near future I'll cling to my 'gut feeling / intuition' My own sixteen year old indestructible / immortal has a nice old Raven III to play with. I'm not going to raise his allowance. That Raven III should be good to go for at least another 150 jumps... If you think it to be a good idea to keep YOUR sixteen year old under the same strict regime I'm keeping mine under, please do write something down in the BSR's - for parental guidance can easely be enforced when it is your parachute, airplane and playground but it becomes a whole new ball-game when they are over 21, not your kid and free to move with their skydiving dollar on to the next premisses... "Whoever in discussion adduces authority uses not intellect but memory." - Leonardo da Vinci A thousand words... Quote Share this post Link to post Share on other sites
Ron 10 #37 February 19, 2005 Quote thanks for all your help, skygods What the hell did I do to piss you off today?"No free man shall ever be debarred the use of arms." -- Thomas Jefferson, Thomas Jefferson Papers, 334 Quote Share this post Link to post Share on other sites
billvon 3,085 #38 February 19, 2005 Dorbie, Sparky, cut it out. This is a very useful bit of research that is going to help us determine how to better train new jumpers. Stop bickering about who knows more statistics, and who should get a room. Sparky, often it doesn't pay to argue with the same people over and over. I've found that after a while it stops being about skydiving and starts being about who's going to get the last word, and no one wins those sorts of battles. Dorbie, at your level of experience, it can really pay to listen. You have some good input too, but sometimes you have to be careful of exceeding a certain advice/skill ratio. Quote Share this post Link to post Share on other sites
Scrumpot 1 #39 February 19, 2005 Quote sometimes you have to be careful of exceeding a certain advice/skill ratio. A common malaise within these boards unfortunately, it seems. Delete away.... -Grantcoitus non circum - Moab Stone Quote Share this post Link to post Share on other sites
mjosparky 4 #40 February 19, 2005 Quote Dorbie, Sparky, cut it out. This is a very useful bit of research that is going to help us determine how to better train new jumpers. Stop bickering about who knows more statistics, and who should get a room. Sparky, often it doesn't pay to argue with the same people over and over. I've found that after a while it stops being about skydiving and starts being about who's going to get the last word, and no one wins those sorts of battles. Dorbie, at your level of experience, it can really pay to listen. You have some good input too, but sometimes you have to be careful of exceeding a certain advice/skill ratio. You are right, I know. Sometimes the frustration level gets a little high. SparkyMy idea of a fair fight is clubbing baby seals Quote Share this post Link to post Share on other sites
airtwardo 7 #41 February 19, 2005 Quote a Prussian stableman. Quote Interesting post...very informative! Over on 'This Side of the Pond', they went by a different title... Over here they were called a Pilot! They would clean out a stall in the stable.... And then "PILOT" outside! It was the worst low life job going, only the dregs of society would gravitate to. Much like the "Pilots" of today! ~ If you choke a Smurf, what color does it turn? ~ Quote Share this post Link to post Share on other sites
HydroGuy 0 #42 February 19, 2005 Do landing fatalities include hitting objects like hangers and trees?Get in - Get off - Get away....repeat as neccessary Quote Share this post Link to post Share on other sites
crewkeith 0 #43 February 20, 2005 sorry just a blanket statment towards the general consesus .The skies are no longer safe I'm back Quote Share this post Link to post Share on other sites
mjosparky 4 #44 February 20, 2005 Quote Do landing fatalities include hitting objects like hangers and trees? I would say yes, pretty much like hitting the ground. SparkyMy idea of a fair fight is clubbing baby seals Quote Share this post Link to post Share on other sites
CornishChris 5 #45 February 21, 2005 Tangent: Quote In the past month, I read that biking deaths for those over 40 (maybe 50?) has gone up dramatically over the past decade. Is it a new problem? Unlikely - the average age of a motorcycle owner has gone up several years, so now there are simply more riders in that age bracket. In the UK this is also the case with older bikers becoming a dangerous group. The reason for this is that these guys learnt to ride 20 or 30 years ago on bikes that were a far cry from those we are riding today. They then stop riding, have a family and then decades later yearn for some excitement and go out and buy a new bike. We call them the back-to-biking group. So they haven't ridden a bike for 20 yrs and have gone out and bought a Honda Fireblade becuase it is cool and they used to ride 900 CC bikes back in the day and then, lo and behold they are in over their heads and fuck up. It would be like someone doing 100 jumps in the sixties then going out tomorrow, buying a nice shiny new rig and jumping with no retraining. Unfortunately it leads to deaths. The solution to both problems in an over simplified manner: TRAINING TRAINING TRAINING CJP Gods don't kill people. People with Gods kill people Quote Share this post Link to post Share on other sites
DancingFlame 0 #46 February 21, 2005 Quote w.r.t. statistics supporting multiple positions, that would really refer to my suggestion of factoring in jumps per fatality (This is NOT the total jumps of the individuals involved in the incidents, these things are very different), and what it means when you consider the overall risk to a jumper vs the risk per jump. You can easily see that someone who does a lot of jumps adopts proportionately greater risk and this might offset experience unless you factor in jumps per fatality in a population segment. That is specifically why I suggested that normalization and why you might draw multiple conclusions from the same data. One would be a risk per jumper(per year presumably) (as Kallend initially requested) and the other would be a risk per jump, the results could (would IMHO) look very different and support different conclusions. That's what I was trying to say. I'd like to see these numbers. I guess 'risk per jumper' number would be a constant. Independent of age or something else. I'm still thinking BSR is a VERY GOOD idea. We've got something of that kind at all DZs in Russia. Sparky, Start a new voting (for/against BSR). I'm pretty sure most people will choose wisely. Quote Share this post Link to post Share on other sites
mjosparky 4 #47 February 21, 2005 Quote Sparky, Start a new voting (for/against BSR). I'm pretty sure most people will choose wisely. I am the wrong one to ask to start a new "voting". I don't need the grief. I do agree with you that most people would choose wisely on an issue like this. The problem is that most people do not frequent these boards. I fear it would be yet another waste of bandwidth the me, me, crowd wanting more data and more studies and the crowd trying to make things safer forced to defend common sense. A lost cause on both side. SparkyMy idea of a fair fight is clubbing baby seals Quote Share this post Link to post Share on other sites
kallend 2,114 #48 February 21, 2005 Quote I fear it would be yet another waste of bandwidth the me, me, crowd wanting more data and more studies and the crowd trying to make things safer forced to defend common sense. A lost cause on both side. Sparky I think that is a rather offensive way of characterizing the debate. Wanting some data before taking action is not a "me me me" response. How would you like it if the FDA took the approach to approving new drugs that no analysis or testing was necessary? "Common sense" has proven to be incorrect on countless occasions.... The only sure way to survive a canopy collision is not to have one. Quote Share this post Link to post Share on other sites
Fast 0 #49 February 21, 2005 Quote Quote I fear it would be yet another waste of bandwidth the me, me, crowd wanting more data and more studies and the crowd trying to make things safer forced to defend common sense. A lost cause on both side. Sparky I think that is a rather offensive way of characterizing the debate. Wanting some data before taking action is not a "me me me" response. How would you like it if the FDA took the approach to approving new drugs that no analysis or testing was necessary? "Common sense" has proven to be incorrect on countless occasions. The difference in that argument is that the FDA errs on the side of saftey. At least in most cases.~D Where troubles melt like lemon drops Away above the chimney tops That's where you'll find me. Swooping is taking one last poke at the bear before escaping it's cave - davelepka Quote Share this post Link to post Share on other sites
penniless 0 #50 February 21, 2005 Quote Quote Quote I fear it would be yet another waste of bandwidth the me, me, crowd wanting more data and more studies and the crowd trying to make things safer forced to defend common sense. A lost cause on both side. Sparky I think that is a rather offensive way of characterizing the debate. Wanting some data before taking action is not a "me me me" response. How would you like it if the FDA took the approach to approving new drugs that no analysis or testing was necessary? "Common sense" has proven to be incorrect on countless occasions. The difference in that argument is that the FDA errs on the side of saftey. At least in most cases. Without some study, how do you know which side safety is on? The experts thought Thalidomide was safe and that HRT was good for women. Quote Share this post Link to post Share on other sites
