# [R] Different results in calculating SD of 2 numbers

Heinz Tuechler tuechler at gmx.at
Wed Jan 16 12:25:18 CET 2008

```At 11:32 16.01.2008, Jim Lemon wrote:
>(Ted Harding) wrote:
> > On 16-Jan-08 08:45:04, Martin Maechler wrote:
> >
> >>>>>>>"RM" == Ron Michael <ron_michael70 at yahoo.com>
> >>>>>>>    on Wed, 16 Jan 2008 00:14:56 -0800 (PST) writes:
> >>
> >>    RM> Hi all,
> >>    RM> Can anyone tell me why I am getting different results in
> >>calculating SD of 2 numbers ?
> >>
> >>    >> (1.25-0.95)/2
> >>    RM> [1] 0.15
> >>    >> sd(c(1.25, 0.95))
> >>    RM> [1] 0.2121320          # why it is different from 0.15?
> >>
> >>because  1 is different from 2 !
> >>If 2 was 1, than sqrt(2) == 1 as well, but actually I don't
> >>think the universe and we all would exist in that case ....
> >>Martin Maechler, ETH
> >
> >
> > Of course we would!! -- Since FALSE implies X is TRUE for any X.
> >
> > But FALSE would also imply that X is FALSE, so you are entitled
> > to your view as well, Martin.
> >
>Then again, as pi might have been equal to 1 prior to the Big Bang, I
>see no reason why sqrt(2) shouldn't have been equal to 1 as well. After
>all, in those days we were all one...
>
>Jim
>

Of course the question is off topic, but I like it. In my
understanding mathematics is a theoretical model, that may or may not
describe properly certain aspects of a "reality". I cannot see, why a
theoretical model should have any influence on our existence, as long
as we don't apply it in an unreasonable way.
To believe in our existence or to prove it is a totally different case.

Heinz

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