[R] post hoc statistical power

[John Fox]

Dear Yuelin,

Another paper critical of post-hoc power calculations is Hoenig and Heisey,
2001. "The Abuse of Power: The Pervasive Fallacy of Power Calculations for
Data Analysis." The American Statistician, 55, 19-24. Hoenig and Heisey show
that so-called "observed power" is simply a re-expression of the p-value.

I hope this helps,
 John

--------------------------------
John Fox, Professor
Department of Sociology
McMaster University
Hamilton, Ontario, Canada L8S 4M4
905-525-9140x23604
http://socserv.mcmaster.ca/jfox

> -----Original Message-----
> From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-
> project.org] On Behalf Of Yuelin Li
> Sent: April-08-08 12:47 PM
> To: r-help at r-project.org
> Subject: [R] post hoc statistical power
> 
> I remember reading about post hoc statistical power on R-help.  But I
> can't seem to find them with RSiteSearch("post hoc statistical power")
> and variations of it.
> 
> I would like to learn more about post hoc statistical power, its
> meaningfulness, advantages and disadvantages.  I thought the issue was
> settled after Tukey's 1993 paper about post hoc statistical power
> being "essentially meaningless once the experiment has been done".
> But they seem to be used, and sometimes encouraged
> (e.g., http://www.informaworld.com/smpp/content~content=a787469931).
> 
> I do not intend to start a debate.  I simply would like to learn
> more.  Can anyone suggest a few articles?  Thanks,
> 
> Yuelin.
> 
> Tukey JW. Tightening the clinical trial. Control Clin Trials.
> 1993;14:266-285.
> 
> 
> 
> =====================================================================
> 
>      Please note that this e-mail and any files transmitted with it may
> be
>      privileged, confidential, and protected from disclosure under
>      applicable law. If the reader of this message is not the intended
>      recipient, or an employee or agent responsible for delivering this
>      message to the intended recipient, you are hereby notified that
> any
>      reading, dissemination, distribution, copying, or other use of
> this
>      communication or any of its attachments is strictly prohibited.
> If
>      you have received this communication in error, please notify the
>      sender immediately by replying to this message and deleting this
>      message, any attachments, and all copies and backups from your
>      computer.
> 
> ______________________________________________
> 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.