[R] expanding factor with NA

[Prof Brian Ripley]

On Mon, 27 Oct 2003, Liaw, Andy wrote:

> [OK, it's not so strange: na.action is not a documented argument for
> model.matrix, and the call to model.frame in model.matrix.default does not
> have ..., but shouldn't it?]


o, as it documented as for arguments to other methods.
-- 
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)
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