[R] reference category for factor in regression

[Berwin A Turlach]

G'day Jos,

On Mon, 19 Jan 2009 15:52:00 +0000
Jos Elkink <jos.elkink at ucd.ie> wrote:

> Thanks for your quick answer. The problem is not so much the LABOUR
> variable, however, but the AGE variable, which consists of about 5
> categories for which I do indeed not create separate dummy variables.
> But R does not behave as expected when deciding on which dummy to use
> as reference category ...

I guess in this case we need more information.

What is the output of "str(AGE)"?  That should tell you which category
is the reference category.  And which category do you expect to be the
reference category?

Cheers,

	Berwin

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