Ian,
I puzzled over this message in a different context, but there could be a
connection. The details of my problem are a bit hazy now, but the essence
was that I fitted an aov model to a subset of the data which happened to
omit one factor level completely.
Then I made predictions from the model.
Predict determined the size of the coef vector from levels(factor), which
was one greater than the number of coefficients in the model.
It could be that dummy.coef, like predict, is calculating the number of
coefs from the level attributes, which with your rather curious C:d term in
the model (do you mean C + C:d, which is equivalent to C/d?) could well
result in a mismatch of vector sizes.
Greg Arnold
Statistics, Social Science Building
Institute of Information Science and Technology
Massey University
P B 11 222
Palmerston Nth
New Zealand
g.arnold@massey.ac.nz
Phone +64 6 350 4254
Fax +64 6 350 2261
-----------------------------------------------------------------------
This message was distributed by s-news@wubios.wustl.edu. To unsubscribe
send e-mail to s-news-request@wubios.wustl.edu with the BODY of the
message: unsubscribe s-news