Re: [R] Posthoc tests for 3-way ANOVA analysis

From: A Ezhil <ezhil02_at_yahoo.com>
Date: Tue 24 Oct 2006 - 12:43:39 GMT


Hi Torsten,

Thanks for your help. I have downloaded the 'multcomp' package (windows ver. 0.4-8, but the source is 0.991-1). When I tried with 'glht' function, it says 'object not found'. Am I missing anything?

Thanks again for your help.

Regards,
Ezhil

>
> On Tue, 24 Oct 2006, A Ezhil wrote:
>
> > Hi All,
> >
> > I have performed a 3-way ANOVA analysis for my
> > experimental data using aov function. My simple R
> > funtion for this is:
> >
> > 3aof <- function(x){
> > m <- data.frame(R,S,T, x);
> > anova(aov(x ~ R+S+T+R*S+R*T+S*T+R*S*T, m) )
> > }
> >
>
> you can use
>
> R> library("multcomp") ### check for version 0.991-1
>
> for some model
>
> R> amod <- aov(x ~ R+S+T+R*S+R*T+S*T+R*S*T, m)
>
> with, say, all-pair comparisons of the levels of
> `T':
>
> R> posth <- glht(amod, linfct = mcp(T = "Tukey"))
>
> various adjusted p-values can be computed using
>
> R> summary(posth)
>
> and confidence intervals (adjusted and unadjusted)
> are available from
>
> R> confint(posth)
>
>
> Hope that helps,
>
> Torsten
>
>
> > Now, I am getting P values for all the main and
> > interactions effects. If I want to perform postdoc
> > test on one of my main effects, say T, what method
> I
> > should use (i have unequal sample size)? Is there
> > anyway I can extend my above '3aof' function to do
> > this?
> >
> > I greatly appreciate your help. Thanks in Advance.
> >
> > Regards,
> > Ezhil
> > Ph.D Student
> > School of Biotechnology
> > AU, India.
> >
> > ______________________________________________
> > R-help@stat.math.ethz.ch 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.
> >
> >
>



R-help@stat.math.ethz.ch 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. Received on Wed Oct 25 03:49:02 2006

Archive maintained by Robert King, hosted by the discipline of statistics at the University of Newcastle, Australia.
Archive generated by hypermail 2.1.8, at Wed 25 Oct 2006 - 04:30:15 GMT.

Mailing list information is available at https://stat.ethz.ch/mailman/listinfo/r-help. Please read the posting guide before posting to the list.