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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

#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.

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

#5

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.

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

#6

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.

> 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?

? It would seem like you have made the connection already. Although I don't see it.

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

#7

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's assuming that they're independent, though, which is certainly false. I'm curious by how much.

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

#8

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.

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.

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

#9

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.

Yes, this can be made precise: For example, consider a uniform distribution on a d-dimensional cube with side length 1. Only a (1/2)^d fraction of the mass is within 0.25 distance of the average in every coordinate.

In high dimensions, almost all the mass is "near the boundary" in at least one coordinate.

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