Hello R help
I have read over many of the help threads on the regular r help
archive and must admit i am still confused.
The data set i wish to analyze is a 2 level nested design with both
factors random.
Response variable: Density of barnacles
Explanatory one: Region ( 4 regions)
Explanatory t
Stephen,
Assuming normally distributed errors (and random effects) you can fit
unbalanced random effects models using REML via either lmer in the
lme4 package or lme in the nlme package. The lme4 package also
provides means of fitting models with non-normal errors, whereas nlme
provides means of
Hi all, I've just completed an analysis of short-tailed shearwater breeding
success in relation to human disturbance using a mixed model. I'd like to
do a power analysis on this now but am unaware of any way to do it. Is it
possible? Does anyone have any ideas?
Thanks,
Caitlin
[[altern
You might want to start with:
JM Hoening and DM Heisey. The abuse of power: The
pervasive fallacy of power calulatons for data analysis.
The American Statistician, 55(1):19–24, 2001.
Hadley
On Wed, Dec 17, 2008 at 5:23 PM, Caitlin Vertigan
wrote:
> Hi all, I've just completed an analysis of sh
You can do it. It is probably easiest to do it by simulation. Simulate
data at several effect sizes (ie when H0 is false) and sample sizes and
count the proportion of times that the model correctly rejects H0. The
big problem is dealing with the random effects. You could treat the
random effects as
On Thu, 18 Dec 2008 10:23:33 +1100,
"Caitlin Vertigan" wrote:
> Hi all, I've just completed an analysis of short-tailed shearwater
> breeding success in relation to human disturbance using a mixed model.
> I'd like to do a power analysis on this now but am unaware of any way
> to do it. Is it po
Caitlin Vertigan wrote:
> Hi all, I've just completed an analysis of short-tailed shearwater breeding
> success in relation to human disturbance using a mixed model. I'd like to
> do a power analysis on this now but am unaware of any way to do it. Is it
> possible? Does anyone have any ideas?
>