The paper by Hoenig & Heisey ("The abuse of power: the
pervasive fallacy of power calculations for data
analysis", The Am Statistician, 2001, vol 55, #1,
19-24) does a nice job of showing the logical flaw in
post-hoc power analysis.
Scott Millis
--- [email protected] wrote:
> All,
>
> I'm posting this at the request of a colleague.
> Please excuse any
> cross-postings.
>
> My colleague was told that some statistical packages
> will do pre-power
> (that is, determining power/sample size before an
> experiment), but not
> post-power (that is, determining the power after an
> experiment). This does
> not make sense to me, as I assumed that the
> algorithms are the same.
>
> Has anyone ever heard this before?
>
> Thanks,
> Jim Seward
>
> *
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> *
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> * http://www.ats.ucla.edu/stat/stata/
>
>
=====
Scott R Millis, PhD, MEd, ABPP (CN & RP)
Director, Office of Clinical Trials
Kessler Medical Rehabilitation Research & Education Corp
1199 Pleasant Valley Way
West Orange, NJ 07052
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