Gee, so much excitement over such a little thing.
So how exactly would you prefer lm() to tell you
what levels of your factors are being taken as the
reference levels?
Post-processing, if necessary, would seem to be
pretty trivial.
If you want to re-run lm() on modified sets of
predictors, what's wrong with editing the lm(...)
command or using update()?
-Peter Ehlers
Idgarad wrote:> How for the love of god can I prevent the lm() function from padding on to
> my factor variables?
>
> I start out with 2 tables:
>
> Table1
> 123123
> 124351
> ...
> 626773
>
> Table2
> Count,IS_DEAD,IS_BURNING
> 1231,T,F
> 4521,F,T
> ...
> 3321,T,T
>
> Everything looks fine when I import the data.
>
> then we get a
>
> oh_crap <- lm(table1 ~ Count + IS_DEAD + IS_BURNING, table2)
>
> Magically when I look at my oh_crap coefficents they get turned into
>
> Count, IS_DEADTRUE, IS_BURNINGTRUE
>
> I get it that it finds them to be factors by how in the name of all that is
> holy do I prevent them from doing that crap since later after a stepwise
> removal I go into one of the models grab what coefficents were kept
> (IS_BURNINGTTRUE now) and read future regressors from the original table
> which read IS_BURNING rather then IS_BURNINGTRUE.
>
> Since there is a mix of numeric and dummy regressors I cannot selectively
> append TRUE to variables names as I don't have control of what
regressors
> get imported (one month there might be 50 and another month 2).
>
> How can I stop lm() from padding onto a coefficent's name?
>
> I have no objection to post processing by finding and assasinating any name
> with the word TRUE appended to the end of a name but in that case then how
> do I change the coeff name?
>
> Maddening... who thought it would be a good idea to append things without
> asking? A simple lm(appendFactor=FALSE) would have been nice... took me 3
> hours to find out what was going wrong on this.... Grabbing coffee, a
carton
> of cigs, and heading outside to smash my head with a brick to make the
> hurting stop....
>
> [[alternative HTML version deleted]]
>
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>
--
Peter Ehlers
University of Calgary
403.202.3921