[R] CART for 0/1 data

[Martin Wegmann]

Dear R-user, 

I tried to generate classification / regression tree with a absence/presence 
matrix of species (400) in different locations (50) to visualise species 
which are important for splitting up two locations. 
Rpart and tree did not work for more than 10 species which is logical due to 
the limited amount of locations (n=50). However the error prompt is a "+" and 
no specific message, but I am pretty sure that I did not enter a false sign 
by mistake. 
Is it allowed at all to use 0/1 data for this statistical technique and if yes 
is there a way or different method to use all 400 species entries?
Otherwise I would apply a PCA beforehand but I would prefer to have the raw 
species informations. 

using R 2.1.1-1 (debian repos.)

regards, Martin


-- 
Martin Wegmann

DLR - German Aerospace Center
German Remote Sensing Data Center
@
Dept.of Geography
Remote Sensing and Biodiversity Unit
&&
Dept. of Animal Ecology and Tropical Biology
University of Wuerzburg
Am Hubland
97074 Würzburg

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