Re: 2 more ASREML questions
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Re: 2 more ASREML questions

> Arthur,
> I am trying to run a large job and I wanted to fit a five-way interaction
> with all smaller interactions but the output in the .asr file didn't
> contain F-statistics for the any of the interaction terms or main effects.
> Is this due to the size of the problem and I have to calculate them
> myself?

The problem is probably one of order of terms and that you have
not expicitly fitted constraints.
There will not be a problem if  mu  is first 
                           and   all terms are in the dense portion
                           and   terms are in standard order e.g.
  mu A B A.B A.C B.C A.B.C etc

In this case ASREML reverses the order for fitting and generates
appropriate marginal sums of squares viz

  A.B.C.D.E | lower order

However, if mu is omitted or not first or if A.B.C.D.E is in the sparce section,
then A.B.C.D.E is fitted before all other terms and there is no
variation left for the other terms.

The solution if you want to fit the model thast way is to constrain the
terms viz  c(A).c(B).c(C).c(D).c(E)
which you might just be able to do.


> Secondly, is there a simple way of fitting a five-way interaction term
> like a*b*c*d*e that will fit all lower order interactions or do I have to
> explicitly have to fit all the interactions?
No. You have to give the full list: making sure that interaction names
do not exceed 20 characters [i.e. you will probably have to use
shortened names.
> Ian Phillips
Arthur Gilmour PhD                           email:
Senior Research Scientist (Biometrics)                 fax: <61> 2 6391 3899
NSW Agriculture                             telephone work: <61> 2 6391 3815
Orange Agricultural Institute                         home: <61> 2 6362 0046
Forest Rd, ORANGE, 2800, AUSTRALIA         

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