[R] rpart question

[Prof Brian Ripley]

On Thu, 25 Jan 2007, Aimin Yan wrote:

> I make classification tree like this code
> p.t2.90 <- rpart(y~aa_three+bas+bcu+aa_ss,
> data=training,method="class",control=rpart.control(cp=0.0001))
>
> Here I want to set weight for 4 predictors(aa_three,bas,bcu,aa_ss).
>
> I know that there is a weight set-up in rpart.
> Can this set-up satisfy my need?

It depends on what _you_ mean by 'set weight'.  You will need to tell us 
in detail what exactly you want the weights to do.

Using the 'weights' argument is specifying case weights (as the help 
says).  There are also 'cost' and 'parms' for other aspects of weighting.

-- 
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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