Re: [R] rpart unbalanced data

From: Dr. Diego Kuonen <>
Date: Fri 21 Jul 2006 - 22:21:44 EST

Dear Helen,

You may want to have a look at


  Diego Kuonen wrote:
> Hello all,
> I am currently working with rpart to classify vegetation types by spectral
> characteristics, and am comming up with poor classifications based on the fact
> that I have some vegetation types that have only 15 observations, while others
> have over 100. I have attempted to supply prior weights to the dataset, though
> this does not improve the classification greatly. Could anyone supply some
> hints about how to improve a classification for a badly unbalanced datase?
> Thank you,
> Helen Mills Poulos

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Received on Fri Jul 21 22:25:22 2006

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