Message-ID: <21ce39b20904210310i139a53berd38642cddd13038a@mail.gmail.com>
Date: 2009-04-21T10:10:10Z
From: William Simpson
Subject: lme for between-within anova
I have the following between-within anova:
aovn1 <- aov(amplitude ~ stereo*site*stimulus +
Error(subject/(site*stimulus)), stereon1)
This works fine. BUT I need to do Tukey HSD multiple comparisons, and
the aov() approach won't work. So I am trying the method posted on
r-help:
lmen1 <- lme(amplitude ~ stereo*site*stimulus, random =
~1|subject/(site*stimulus), stereon1)
This doesn't work:
> lmen1 <- lme(amplitude ~ stereo*site*stimulus, random = ~1|subject/(site*stimulus), stereon1)
Error in getGroups.data.frame(dataMix, groups) :
Invalid formula for groups
Please tell me what to do to get the lme() fit to work.
After I get lmen1, I will do:
anova(lmen1)
summary(lmen1)
summary(glht(lmen1, linfct=mcp(V="Tukey")))
Please tell me if that sounds right.
Thanks very much for any help!
Bill
============= This is the example I am following (with modifications
for my expt design)
You want to use lme() in package nlme, then glht() in the multcomp
package. This will give you multiplicity adjusted p-values and
confidence intervals.
## Example
require(MASS) ## for oats data set
require(nlme) ## for lme()
require(multcomp) ## for multiple comparison stuff
Aov.mod <- aov(Y ~ N + V + Error(B/V), data = oats)
Lme.mod <- lme(Y ~ N + V, random = ~1 | B/V, data = oats)
summary(Aov.mod)
anova(Lme.mod)
summary(Lme.mod)
summary(glht(Lme.mod, linfct=mcp(V="Tukey")))