I am very new to R and thus find those examples a bit confusing although I
believe the solution to my problems lies there.
Lets take for example an experiment in which I had two between subject
variables - Strain and treatment, and one within - exposure. all the
variables had 2 levels each.
I found an interaction between exposure and Strain and I want to compare
Strain A and B under every exposure (first and second).
The general model was with that function:
aov(duration~(Strain*exposure*treatment)+Error(subject/exposure),data)
in summary(aovmodel) there was a significant interaction between exposure
and strain.
how (using those HH packages) can I compare Strains under the conditions of
exposure?
BTW - I don't have to use aov (although its seems to be the simplest one).
Thank you very much.
On Mon, Dec 21, 2009 at 12:16 AM, Richard M. Heiberger <r...@temple.edu>wrote:
> For simple effects in the presence of interaction there are several
> options included in the HH package. If you don't already have the HH
> package, you can get it with
> install.packages("HH")
>
> Graphically, you can plot them with the function
> interaction2wt(..., simple=TRUE)
> See the examples in
> ?HH::interaction2wt
>
> For tests on the simple effect of A conditional on a level of B, you
> can use the model formula B/A and look at the partition of the sums of
> squares using the split= argument
> summary(mymodel.aov, split=<put your details here>)
>
> For multiple comparisons from designs with Error() terms, you need to
> specify the same sums of squares with an equivalent formula that doesn't
> use the Error() function. See the maiz example in
> ?HH::MMC
> Read the example all the way to the end of the help file.
>
> Rich
>
>
[[alternative HTML version deleted]]
______________________________________________
R-help@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.
