[R] Anova - adjusted or sequential sums of squares?

[(Ted Harding)]

On 20-Apr-05 michael watson \(IAH-C\) wrote:
> I guess the real problem is this:
> 
> As I have a different number of observations in each of the
> groups, the results *change* depending on which order I
> specify the factors in the model.  This unnerves me. With a
> completely balanced design, this doesn't happen - the results
> are the same no matter which order I specify the factors.  
> 
> It's this reason that I have been given for using the so-called
> type III adjusted sums of squares...

This is inevitable. It's not for nothing that unbalanced "designs"
are called "non-orthogonal".

What are the "E" and "NE" effects corresponding to the
observations plotted at "+" in the following diagram?


      NE
      /
     /
    /
   /
  /   +
 /
o------------------>E

Best wishes,
Ted.


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Date: 20-Apr-05                                       Time: 16:54:21
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