A concrete type I/III Sum of square problem

Thanks Brian for the reference.
  I just discover that it is available in our 
library so I going to take it & read it soon.
Actually, I don't even know the difference 
between a multistratum vs a single-stratum AOV. A 
quick search on google returned me the R materials so that I imagine
that these concepts are quite specific to R.

I will read the book first before asking for more informations.

Thanks

Sylvain Cl??ment

More to the point, you are confusing 
multistratum AOV with single-stratuam AOV.  For 
a good tutorial, see MASS4 (bibliographic 
information in the R FAQ).  For unbalanced data 
we suggest you use lme() instead.

--
Brian D. Ripley,                  ripley at stats.ox.ac.uk