Why isn't everything normally distributed?

Re:Why isn't everything normally distributed? by logicallee on Thursday July 20, 2017 @07:41PM (#14817105)

thanks! Very interesting. Is the standard deviation still useful for some of the other distributions you mentioned, that look vaguely Gaussian?

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Re:Why isn't everything normally distributed? by R_haterade on Thursday July 20, 2017 @08:17PM (#14817242)

You're referring to the square root of the second moment about the mean. The short answer is yes, it's always useful, provided you have an estimator.

Check out Chebyshev's inequality.

Just don't start talking about it to your pointy-haired boss. You'll get fired.

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Re:Why isn't everything normally distributed? by logicallee on Friday July 21, 2017 @01:52AM (#14818355)

thanks. but what does your last line, about the boss mean?

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Re:Why isn't everything normally distributed? by R_haterade on Monday July 24, 2017 @03:53PM (#14842049)

That this sort of knowledge is often uninteresting to non-technical types.

I'm pretty jaded at this point.

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Re:Why isn't everything normally distributed? by dbaupp on Thursday July 20, 2017 @09:14PM (#14817412)

For the specific example of the Cauchy distribution, the standard deviation isn't defined.

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Re:Why isn't everything normally distributed? by thanatropism on Thursday July 20, 2017 @07:49PM (#14817135)

The standard deviation is defined as

E[(X-EX)^2]

If EX = infinity but X is finite with prob > 0, the standard deviation will be infinite too.

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