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When the U.S. air force discovered the flaw of averages

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Re: When the U.S. air force discovered the flaw of averages

#11

Post by frankc »

TTPrograms wrote: post #5
banku_brougham wrote: post #3

The concept of no members of a group fitting into the average range for all observations is reminiscent of the 'curse of dimensionality'. Can anyone with a data science background make the connection here? Secondly, this seems to explain why everyone hates autocorrect.

Yeah, in this case if the 10 traits are independent and the chance of falling in the "average range" is 1/3 for any one trait then the probability of any one soldier falling the the average range for 10 traits is (1/3)^10 = 1/59049.

That is true, but this can be just as much an issue in 1 dimension. Consider that the average person has roughly 1 testicle. I think it's about understanding distributions, and joint distributions are a big part of that.

Re: When the U.S. air force discovered the flaw of averages

#12

Post by danbruc »

gefh wrote: post #8
TTPrograms wrote: post #5

Earlier quoted context omitted.

Yeah, in this case if the 10 traits are independent and the chance of falling in the "average range" is 1/3 for any one trait then the probability of any one soldier falling the the average range for 10 traits is (1/3)^10 = 1/59049.

But you might naturally assume a strong correlation between the middle range of each dimension - the interesting conclusion is that it's not nearly as strong as our intuition suggests.

But even if they are correlated that does not necessarily imply that being average on one dimension makes it likely to be average on other dimensions. I can well imagine that correlations conspire against you, i.e. that being average in one dimension makes it likely to be non-average in another dimension.

Re: When the U.S. air force discovered the flaw of averages

#13

Post by my5thaccount »

Articles like this remind me how rational and practical the military is. I know so many brilliant military minds, yet war itself seems outdated and plagued by so many emotionally irrational decisions. I can't reconcile those two thoughts.

How can people inside the military be so incredibly smart, yet still think it makes sense to ... you know, kill people's friends and families and not expect them to become terrorists.

What am I missing? It can't just be greed. Military industrial complex. The military minds aren't smarter than that? I struggle with it.

Re: When the U.S. air force discovered the flaw of averages

#14

Post by gefh »

danbruc wrote: post #12
gefh wrote: post #8

Earlier quoted context omitted.

But you might naturally assume a strong correlation between the middle range of each dimension - the interesting conclusion is that it's not nearly as strong as our intuition suggests.

But even if they are correlated that does not necessarily imply that being average on one dimension makes it likely to be average on other dimensions. I can well imagine that correlations conspire against you, i.e. that being average in one dimension makes it likely to be non-average in another dimension.

That appears to be the case, but is counter-intuitive enough that it took the air force years to realize it.

Re: When the U.S. air force discovered the flaw of averages

#15

Post by ccvannorman »

my5thaccount wrote: post #13

Articles like this remind me how rational and practical the military is. I know so many brilliant military minds, yet war itself seems outdated and plagued by so many emotionally irrational decisions. I can't reconcile those two thoughts. How can people inside the military be so incredibly smart, yet still think it makes sense to ... you know, kill people's friends and families and not expect them to become terrorist…

Momentum.

Also, it's easy to paint yourself as "the good guy with all the government sponsored guns and military contracts" who will "keep the other good people safe" because "you're better, smarter, more capable and more honorable than them." It's a very sexy and lucrative mindset, so it shouldn't be a surprise that it's pervasive.

Re: When the U.S. air force discovered the flaw of averages

#18

Post by SixSigma »

my5thaccount wrote: post #13

Articles like this remind me how rational and practical the military is. I know so many brilliant military minds, yet war itself seems outdated and plagued by so many emotionally irrational decisions. I can't reconcile those two thoughts. How can people inside the military be so incredibly smart, yet still think it makes sense to ... you know, kill people's friends and families and not expect them to become terrorist…

Do military people disagree with your analysis about killing ?

Re: When the U.S. air force discovered the flaw of averages

#19

Post by my5thaccount »

DigitalJack wrote: post #16

Has nobody heard of quetelet?

No, but thanks for bringing him to my attention! It's amazing how someone like that so long ago could have such an impact on so many fields, while today, it takes teams of people to win the Nobel prize in a single field.

It's a testament to how much we know today relative to yesterday.

Re: When the U.S. air force discovered the flaw of averages

#20

Post by azernik »

my5thaccount wrote: post #13

Articles like this remind me how rational and practical the military is. I know so many brilliant military minds, yet war itself seems outdated and plagued by so many emotionally irrational decisions. I can't reconcile those two thoughts. How can people inside the military be so incredibly smart, yet still think it makes sense to ... you know, kill people's friends and families and not expect them to become terrorist…

a) war a very unforgiving environment - bad policies become apparent very quickly under pressure

b) the things you are against ("kill people's friends and families and not expect them to become terrorists") are often policies not under military control. If the government doesn't want to spend the money or annoy its allies enough to solve the root causes, there's not much a soldier on the ground can do except mitigate the damage (and yes, that often includes actions that perpetuate a bad status quo)

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