Hi :)

Try this with other distributions too... And then search for 'central limit
theorem'.

Cheers,

Tsjerk


On Fri, Oct 25, 2013 at 4:48 PM, Kramer, Christian <
Christian.Kramer@uibk.ac.at> wrote:

> Hi there,
>
> I have found a strange behavior in R that puzzles me - maybe it is a bug
> or a basic scientific misunderstanding of mine… anyway, I would highly
> appreciate some feedback on this, since I did not find anything on the
> internet.
>
> I am trying to simulate a t-distribution by adding up normally distributed
> numbers:
>
> a  <- (rnorm(1000) + rnorm(1000) + rnorm(1000) )/3
>
> However, when I look at the distribution using
>
> qqnorm(a)
>
> this looks more like a normal distribution than a t-distribution:
>
> b <- rt(1000,2)
> qqnorm(b)
>
> Is this to be expected? Or is this an issue with the random number
> generator or something else?
>
> Thanks a lot for replies in advance,
> Christian
>
> --------------------------------------------
> Dr. Christian Kramer
> Theoretical Chemistry
> University of Innsbruck
> Innrain 82
> A-6020 Innsbruck
> Tel.: +43 512 507 57103
> Homepage: http://homepage.uibk.ac.at/~c72448/kramer.html
> Email: Christian.Kramer@uibk.ac.at
>
> ______________________________________________
> R-help@r-project.org mailing list
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> PLEASE do read the posting guide
> http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>



-- 
Tsjerk A. Wassenaar, Ph.D.

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