[R] Forward stepwise procedure w/ stepAIC

[Prof Brian Ripley]

It starts with the initial model you gave it, which contains all your 
explanatory variables already.  You presumably wanted to use a simpler 
model to start with.  As in:

Arguments:

  object: an object representing a model of an appropriate class. This
          is used as the initial model in the stepwise search.


On Wed, 18 Jun 2003 MZodet at ahrq.gov wrote:

> I'm attempting to select a model using stepAIC.  I want to use a forward
> selection procedure.  I have specified a "scope" option, but must not be
> understanding how this works.  My results indicate that the procedure begins
> and ends with the "full" model (i.e., all 17 independent variables)...not
> what I expected.  Could someone please point out what I'm not understanding?

[output snipped]

-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
1 South Parks Road,                     +44 1865 272866 (PA)
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