Hi,
I have an experiment where I measured two times the dependent variable (called 
<b>Intention</b>). So, I have IntentionPre and IntentionPost.
I am working with an anova for an independent variable called 
<b>NumberOfModules</b>.
The problem is that if I run the aov(intentionpre~NumberOfModules) I have that 
there is a significant difference between the means.
I want to know the difference between pre and post intentions based on the 
NumberOfModules. So, I've been told that I should make an ancova and the 
IntentionPre variable will work as a covariable, but I don't really know how 
should organize my data in order to get that.
My dataframe currently has the following columns: <b>Email (userId), Intention 
(pre+post values), constrast (is it pre or post value?), and 
NumberOfModules.</b>
What I would do if there were no significant difference between the means for 
the <b>intentionpre</b>, would be:
<i>aov(intention~constrats*NumberOfModules+Error(Email/constrats), 
gdataframe)</i>
What I was thinking to do is adding a column with  <b>IntentionPre</b> 
(duplicated for every pre and post value for the <b>Intention</b> column) and 
running it like:
<i>aov(intention~intentionPre + 
constrats*NumberOfModules+Error(Email/constrats), gdataframe)</i>
Is that a correct reasoning?
Any help would be great!!

Camilo V                                          
        [[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.

Reply via email to