So how do I test if there is a difference between groups?
On 12/1/05, Joseph Coveney <[email protected]> wrote:
> Raphael Fraser wrote:
>
> Can anyone explain why the distribution of the test statistic is 384
> for all 1000 permutations?
>
> ct grp
> 121 1
> 150 1
> 113 1
> 90 0
> 80 0
> 85 0
>
> permute ct sum=r(sum), saving(permsum, replace) seed(1440) reps(1000):
> sum ct if grp
> use permsum, clear
>
> --------------------------------------------------------------------------------
>
> Stata is doing what you instructed it to do: disregard group 0, permute the
> values within group 1, and repeatedly calculate the sum of these same three
> group 1 values, which will be 384 however permuted.
>
> Joseph Coveney
>
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>
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