3 ms·

As explained in the article, there's no perfect measure for this. Hour of activity is very relative, but I agree that it's probably the safer bet. In contrast,

As explained in the article, there's no perfect measure for this. Hour of activity is very relative, but I agree that it's probably the safer bet. In contrast, the only other remotely decent timeframe I could think is per-day of activity since that'd account for a more down-to-earth top of the head calculation. I'd be interested in e.g. what is the probability of dying on 1 day of skiing (3-4h) vs 1 day of skydiving (1 jump).

lb1lf 7y ago
-While I agree with your point, I'd just like to chime in that skydivers tend to do several jumps in a day. I tend to spend a few days at a skydiving hotspot every summer - not to do any jumping myself, if the plane works I'm perfectly happy just staying in my seat, thank you very much - but the kids love to watch, and it is one of few places with a huge playground where I can just let my kids roam free and not be worried about them at all. Anyway - the Cessna Caravan managed 3-4 cycles/hour, and from what I could tell, there were approx. 20-25 people jumping that day - so, every other trip you got to jump, for perhaps a dozen jumps in a day for the most eager ones.
- eunoia 7y ago
  A half dozen jumps in a day is pretty long day of skydiving although you can certainly do more if you're committed. (and helps if you have someone else packing your chute) Anecdotally I've met old timers with over 10k total jumps. Edit with some more info: Most common plane we jumped (in CO) was a DHC-6 Twin Otter that seated about 25. That thing was turning non stop every day. Biggest plane I've ever jumped was a DC-3/C-47 in AZ that seated somewhere around 50 and took two passes over the DZ to get everyone out.
metacritic12 7y ago
It would be nice to have a table of how many hours per day does a moderate hobbyist do for each of the activities. For biking, I can imagine 4-6 hours being moderate, and for skydiving it would be just 10 minutes. That way, we can do the above math ourselves. Also, for some activities, how you measure time is really important. Skydiving is such a short duration activity that it really matters if you are measuring a) free fall time b) parachute time c) between plane and ground time d) between takeoff and landing zone time e) time spent at skydiving area.
ashearer 7y ago
Measuring "per participation decision" often makes more sense than "per participation hour" when deciding whether to do an activity. (It could be shortened to "per event", defining an "event" to be the result of one decision.) In explaining the choice of per-hour, the author gave the example of choosing either an afternoon riding a mountain bike or an afternoon flying a sailplane. The example works because they involve about the same number of hours. But it's also the same number of decisions, so per-event works just as well there. Per-event fixes distortions for quick activities, where durations are meaningless because they're dominated by setup time that isn't counted (or alternatively, the risk varies by multiple orders of magnitude depending on whether you count the overhead). The chart shows summiting Everest as being 100x safer than base jumping. But if you're deciding which activity to do, it's more relevant to compare risk per-summit to risk per-jump-trip (say, 5 jumps?) or even risk per-jump, since you can calibrate the number of jumps on your trip based on your risk tolerance, but you can't do a fractional summit. Using the author's numbers, jumping has a risk of 0.13% per jump, or 0.67% for a trip with 5 jumps. Everest has a risk of 6.5%. So in terms more relevant to decision-making, a decision to summit Everest comes with a 10x higher risk of death than a decision to go base jumping, instead of 100x lower as the chart might lead you to think.

lb1lf 7y ago

-While I agree with your point, I'd just like to chime in that skydivers tend to do several jumps in a day. I tend to spend a few days at a skydiving hotspot every summer - not to do any jumping myself, if the plane works I'm perfectly happy just staying in my seat, thank you very much - but the kids love to watch, and it is one of few places with a huge playground where I can just let my kids roam free and not be worried about them at all. Anyway - the Cessna Caravan managed 3-4 cycles/hour, and from what I could tell, there were approx. 20-25 people jumping that day - so, every other trip you got to jump, for perhaps a dozen jumps in a day for the most eager ones.

eunoia 7y ago
A half dozen jumps in a day is pretty long day of skydiving although you can certainly do more if you're committed. (and helps if you have someone else packing your chute) Anecdotally I've met old timers with over 10k total jumps. Edit with some more info: Most common plane we jumped (in CO) was a DHC-6 Twin Otter that seated about 25. That thing was turning non stop every day. Biggest plane I've ever jumped was a DC-3/C-47 in AZ that seated somewhere around 50 and took two passes over the DZ to get everyone out.

metacritic12 7y ago

It would be nice to have a table of how many hours per day does a moderate hobbyist do for each of the activities. For biking, I can imagine 4-6 hours being moderate, and for skydiving it would be just 10 minutes. That way, we can do the above math ourselves. Also, for some activities, how you measure time is really important. Skydiving is such a short duration activity that it really matters if you are measuring a) free fall time b) parachute time c) between plane and ground time d) between takeoff and landing zone time e) time spent at skydiving area.

ashearer 7y ago

Measuring "per participation decision" often makes more sense than "per participation hour" when deciding whether to do an activity. (It could be shortened to "per event", defining an "event" to be the result of one decision.) In explaining the choice of per-hour, the author gave the example of choosing either an afternoon riding a mountain bike or an afternoon flying a sailplane. The example works because they involve about the same number of hours. But it's also the same number of decisions, so per-event works just as well there. Per-event fixes distortions for quick activities, where durations are meaningless because they're dominated by setup time that isn't counted (or alternatively, the risk varies by multiple orders of magnitude depending on whether you count the overhead). The chart shows summiting Everest as being 100x safer than base jumping. But if you're deciding which activity to do, it's more relevant to compare risk per-summit to risk per-jump-trip (say, 5 jumps?) or even risk per-jump, since you can calibrate the number of jumps on your trip based on your risk tolerance, but you can't do a fractional summit. Using the author's numbers, jumping has a risk of 0.13% per jump, or 0.67% for a trip with 5 jumps. Everest has a risk of 6.5%. So in terms more relevant to decision-making, a decision to summit Everest comes with a 10x higher risk of death than a decision to go base jumping, instead of 100x lower as the chart might lead you to think.