Re: [OT] Mathematics and the uselessness of numbers (was Re: Help buying Economic Printer)
On 31 Jul, Johannes Wiedersich wrote:
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> [snip]
>
> Sorry for joining this OT thread.
>
> Don't get misled by the subject; this has nothing to do with
> mathematics:
>
> 1) stddev's only apply, if temperatures would vary statistically and
> would therefore show a Gaussian distribution around a mean value.
> Neither is the case.
>
The definition of standard deviation has nothing to do with Gaussian
distributions. It is arguable more useful if the variable varies
randomly (Gaussian distribution).
> 2) If temperatures would vary statistically, it would be enough to
> give the stddev, because 'above' and 'below' would be the same value.
>
> The fact that 'above' and 'below' are generally different values, is a
> direct hint that 1) does not apply. This is probably one of the
> reasons why meteorologists give mean temperatures in January and July,
> but no stddev.
>
> Johannes
>
One can certainly give the standard deviation of maximum and minimum
temperatures. It may not be useful for calculating other figures of
merit though, especially if the time interval considered is small.
-Chris
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| Christopher Judd, Ph. D. judd@wadsworth.org |
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