multivariate tree

[Erik van Zwet <evanzwet@math.leidenuniv.nl>]

Dear all,

I'd like to use Splus or R to fit a regression tree to a 
multivariate response variable. In fact, the response 
variable is a function sampled at 96 time points. I 
think the deviance at a node should simply be the 
L2 distance of all the members to their mean vector.

Hopefully, someone has some code that does this.
If not, then it seems rpart() could be modified, but 
having no C experience at all, I'd need some guidelines 
or examples on how to do that.

Thanks,
Erik van Zwet