Re: [R] learning decision trees with one's own scoring functins

From: Philippe Grosjean <phgrosjean_at_sciviews.org>
Date: Fri 26 Aug 2005 - 18:14:49 EST

Hello,

You have access to the C code of the function in the *source* of the package. You can modify it and recompile the package and function (its better then to give a different name!).
Best,

Philippe Grosjean

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zhihua li wrote:
> Hi netters,
>
> I want to learn a decision tree from a series of instances (learning
> data). The packages
> tree or rpart can do this quite well, but the scoring functions
> (splitting criteria) are
> fixed in these packages, like gini or something. However, I'm going to
> use another scoring
> function.
> At first I wanna modify the R code of tree or rpart and put my own
> scoring function in. But it seems that tree and rpart perform the
> splitting procedure by calling external C functions, which I have no
> access to. So do I have to write R code from scratch to build the tree
> with my own scoring functions? It's a really tough task. Or r there
> other R packages that can do similar things with more flexible and
> extensible code?
>
> Thanks a lot!
>
>
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R-help@stat.math.ethz.ch mailing list
https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html Received on Fri Aug 26 18:21:31 2005

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