did you try to fit your data with a skew-normal/skew-t distribution?
If that works, you can use simulation.
Kjetil
On Tue, Mar 15, 2011 at 2:31 AM, Lao Meng <laomeng.3 at gmail.com>
wrote:> Hi all:
> I have a question on sample size calculation of 2 groups of data. If 2
> groups of data are all normal distribution, then I can use the function
> "n.indep.t.test.eq" from samplesize package.But if 2 groups of
data are all
> skewed distribution, but not normal distribution,how can I calculate the
> sample size then?
> I've tried many transformation (e.g. log arcsin?) in order to transfer
the
> skewed distribution data into normal distribution data, but failed. So what
> I can do is only find a calculation method to do with skewed data.
>
> Any suggestions from you are welcome.
> Thanks a lot for your help.
>
> My best.
>
> ? ? ? ?[[alternative HTML version deleted]]
>
>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>
>