R help - Apr 2004 - coding of categories in rpart

Hello,

I am using rpart to derive classification rules for customer segments.
I have a few categorical variables in the set of independent variables.
For instance,

Account Size can be (Very-Small, Small, Medium, Large, V-Large)

Rpart seems to encode these categories into: a,b,c,d,e

The results are expressed in terms of the encoded values.

How do I find out what encoding was used by rpart.  i.e.
what categories in my input set do a, b, c,... correspond to?

thanks,
Prabhakar

On Tue, 27 Apr 2004, Prabhakar Krishnamurthy wrote:
> I am using rpart to derive classification rules for customer segments.
> I have a few categorical variables in the set of independent variables.
> For instance,
> 
> Account Size can be (Very-Small, Small, Medium, Large, V-Large)
> 
> Rpart seems to encode these categories into: a,b,c,d,e
It doesn't.  That is one output representation (of several), of the factor
levels.
> The results are expressed in terms of the encoded values.
> 
> How do I find out what encoding was used by rpart.  i.e.
> what categories in my input set do a, b, c,... correspond to?
By reading the documentation!  E.g. ?text.rpart.

-- 
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)
Oxford OX1 3TG, UK                Fax:  +44 1865 272595