[R] type II and III Sum square whit empty cells
Mario Morales
malfonso at telecom.com.co
Tue Apr 11 19:04:30 CEST 2006
Dear all
I need to run an anova from a factorial model
y_{ijk}=\alpha_i+\beta_j+(\alpha\beta)_{ij}+e_{ijk}
and calculate type II and III sums of square, but I have an empty
cells, so anova function from package car fail. (I believe)
y<-c(7,13,6,10,8,11,8,3,7,5,65)
a<-as.factor(c(1,1,2,2,3,3,3,1,1,1,2))
b<-as.factor( c(rep(1,7),rep(2,4)) )
table(b,a) # cell (2,3) is empty
mod<-lm(y~ a+b+a:b)
library(car)
Anova(mod,type="II") # don't work
How can I calculate type II and III sum of square whit empty cell?
Thanks a lot
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