[R] step() and stepAIC()

[Murray Jorgensen]

The birth weight example from ?stepAIC in package MASS runs well as
indeed it should.

However when I change stepAIC() calls to step() calls I get warning
messages that I don't understand, although the output is similar.

Warning messages:
1: In model.response(m, "numeric") :
   using type="numeric" with a factor response will be ignored
(and three more the same.)

Checked with 2.7.0 on Os X and 2.6.2 on Windows.

Cheers,  Murray
-- 
Dr Murray Jorgensen      http://www.stats.waikato.ac.nz/Staff/maj.html
Department of Statistics, University of Waikato, Hamilton, New Zealand
Email: maj at waikato.ac.nz                                Fax 7 838 4155
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