[R] rpart unbalanced data

[Dr. Diego Kuonen]

Dear Helen,

You may want to have a look at

  http://www.togaware.com/datamining/survivor/Predicting_Fraud.html

Greets,

  Diego Kuonen


helen.mills at yale.edu 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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