[R] ss's are incorrect from aov with multiple factors

John Christie jc at or.psychology.dal.ca
Sat Jul 12 02:57:36 CEST 2003

On Friday, July 11, 2003, at 09:38  PM, JRG wrote:

> On 11 Jul 03, at 21:20, John Christie wrote:
> In what sense are the SSs "incorrect", exactly?  And what do you think 
> the "correct" values should be?

Well, if I take the residuals for one of the main effects I should be 
able to calculate a confidence interval from it that has some 
relationship to the actual values for that effect so that an accurate 
plot can be made.  The transformation isn't too hard, I just need to 
divide them by the number of factors in the other term.  But, my 
recollection is that this isn't true for other stats packages and may 
lead people who are new and trying to calculate them for the first time 
to incorrect conclusions.  The reported values should be corrected.  
Although, my recollection could be wrong.

More information about the R-help mailing list