[R] Deviance function in regression trees

2006-08-29 Thread Solomon Dobrowski
Hello all. I have heard over and over that CART and its various tree-like brethren are non-parametric techniques. When I read the chapter in Chambers and Hastie on tree-based models it states that tree-based models can be generalized (GTMs) in a manner similar to GLMs by specifying a different

Re: [R] Deviance function in regression trees

2006-08-29 Thread Prof Brian Ripley
The short answer is that a Poisson distribution is a discrete distribution: if that is appropriate to your data the rpart function (in the package of that name) has a suitable option. On Mon, 28 Aug 2006, Solomon Dobrowski wrote: Hello all. I have heard over and over that CART and its various