Math problem

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dbodner
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Joined: Tue Jan 18, 2005 11:24 pm
Location: Arlington

Math problem

Post by dbodner »

Here's a probability problem for those who can remember that far back in their math education.

If the probability of landing my HG on my knees is 0.1 (10%), and
the probability of my wearing shorts while flying is 0.01 (1%), then
the probability of both events happening simultaneously should be 0.001, or one in one thousand.

And, any two times that I do fly in shorts give me a 1% probability of landing on my knees both times.

Somehow I seem to be beating these odds. The two times I can remember wearing shorts while flying ended with skinned knees. I can see two possible solutions: Upgrade my somewhat pathetic landing skills or reduce my incidence of wearing shorts. While there appears to be greater room for improvement in my landings (at the current 10% incidence level) than for my wardrobe (at the current 1%), I feel pretty safe in assuming that, in the real world, I have a greater probablility of positively affecting my outcomes by addressing the latter. Therefore, no more shorts.
David Bodner
brianvh
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Re: Math problem

Post by brianvh »

Ah, but that's ignoring cross correlations.

If you are wearing shorts, the damage will be about 10 times worse, making the universe about 100 times more eager to smack you when the smackin's good (the mob rule of sale events). Since it's contingent statistics (only happens when you are wearing shorts), for those times the old 1% chance of landing on your knees becomes multiplied by 100 to give you 100% certainty of arriving at the end of the dust cloud as a bloody mess. It's all there in your stats textbook.
Brian Vant-Hull
dbodner
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Re: Math problem

Post by dbodner »

And, hence, the difference between my relatively naive and elementary grasp of mathematics and the more sophisticated understanding afforded by post-graduate education. Brian, your knowledge humbles me. 8)
David Bodner
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davidtheamazing1
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Re: Math problem

Post by davidtheamazing1 »

Fly with knee pads, and the chance of scraping your knees on a bell landing will approach zero.
bustedwing2
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Joined: Thu Jan 06, 2005 10:58 pm
Location: McConnellsburg,Pa

Re: Math problem

Post by bustedwing2 »

You're forgetting Murphy's law,therefore flying with kneepads will always result in a broken downtube. RichB
mcgowantk
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Joined: Thu Jan 06, 2005 11:30 pm

Re: Math problem

Post by mcgowantk »

In financial statistics, there is a book called "The Black Swan" that discusses low probability extreme events. One aspect is that there are more "black swans" than you might forecast. You should write the "Black and Blue Knees" book.

Tom McGowan
air_medal
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Joined: Wed Jul 27, 2005 1:56 pm

Re: Math problem

Post by air_medal »

Math-wise, our calculation would be correct if both landing on your knees and wearing shorts are independent outcomes.

Your problem is more likely to be a result of 'reporting error.' You tend to remember the stuff that gets your attention.

That said, I think that "long pants are just a crutch for people who don't want to work on their landing." :wink:
Joe G.
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