I can't recall if either of these solutions handle uneven sample sizes, but
you might try Roger Newson's -powercal- from SSC or the free non-Stata
software package G*Power from
http://www.psycho.uni-duesseldorf.de/abteilungen/aap/gpower3/ .
David
--
David Radwin
Senior Research Associate
MPR Associates, Inc.
2150 Shattuck Ave., Suite 800
Berkeley, CA 94704
Phone: 510-849-4942
Fax: 510-849-0794
www.mprinc.com
> -----Original Message-----
> From: owner-statalist@hsphsun2.harvard.edu [mailto:owner-
> statalist@hsphsun2.harvard.edu] On Behalf Of Matthew Bombyk
> Sent: Wednesday, January 23, 2013 1:25 AM
> To: statalist@hsphsun2.harvard.edu
> Subject: st: Sample size calculation with uneven sample sizes
>
> Dear Statalist,
>
> I have a question about power calculations. I currently have a
> baseline survey dataset, and we are planning the followup. I would
> like to do sample size calculations using various
> assumptions/requirements, and on several variables. However, the
> -sampsi- command in Stata only allows for power calculations with
> uneven sample sizes, not sample size calculations, unless you have a
> fixed ratio. Other programs such as Optimal Design appear to have this
> feature, but it is unwieldy to perform many power calculations using
> different variables and parameters. Does anyone have a solution to
> this problem in Stata?
>
> Thanks,
>
> --
> Matthew Bombyk
>
> Project Coordinator
> Innovations for Poverty Action (IPA)
> Ulaanbaatar, Mongolia
> Tel: +976 9990 1542
>
> www.poverty-action.org
> Fighting poverty with innovation, evidence, and action
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