[R-sig-eco] ICC confidence intervals and power analysis for random effects in lmer?

[Brian Inouye]

In addition to Bob O'Hara's suggestion, here is another citation you can 
give the reviewer/editor, as to why retrospective power analyses are a 
waste of time.

Hoenig, J. M. and D. M. Heisey (2001). "The abuse of power: the 
pervasive fallacy of power calculations for data analysis." American 
Statistician 55(1): 19 - 24.

Last year the ESA updated its author guidelines for reporting 
statistics, and removed a suggestion to report power analyses that had 
been inserted in the 1980s.

-Brian Inouye
Florida State University
Chair, statistical ecology section of the ESA


On 4/12/2012 6:00 AM, r-sig-ecology-request at r-project.org wrote:
> 2) A reviewer requested a power analysis of the ability to detect a
> significant random effect. Any tips on how to approach that?
Report the random effect and confidence intervals. Retrospective power 
analyses are pretty pointless (e.g. see 
http://beheco.oxfordjournals.org/content/14/3/446.full), unless you're 
planning to repeat the experiment. Bob