How about:
set seed 12345
gen random = uniform()
sort random, stable
drop if id == 890800 //subject that wasn't suitable dropped
drop if _n>40
?
On Tue, Apr 1, 2008 at 8:38 AM, raoul reulen <[email protected]> wrote:
> Hi Statalisters,
>
> I am trying to get a random sample of 40 subjects from a dataset of a
> few hundred subject. This is what I did:
>
> .set seed 12345
> .gen random = uniform()
> .sort random, stable
> .drop if _n>40
>
>
> For various reasons, it might be that some subjects in the sample are
> not suitable for selection and I want to exclude them from the sample
> and from the overall dataset.
>
> So I selected another sample, however, when I did that other subjects
> were selected as well.
>
> .drop if id == 890800 //subject that wasn't suitable dropped
> .set seed 12345
> .gen random = uniform()
> .sort random, stable
> .drop if _n>40
>
>
> What I want is to keep the original 39 subjects as in the old sample
> in and just replace the subject that wasn't suitable. Any suggestions
> would be appreciated.
>
> Many thanks.
>
> Raoul
>
>
>
>
> --
> -------------------------------------------------------
> Raoul C. Reulen
> Cancer Research UK Training Fellow
> *
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