[R] oversampling code

[Comcast]

On Oct 31, 2011, at 1:54 PM, loubna ibn majdoub hassani <loubn181 at gmail.com> wrote:

> Hir
> I have an umbalanced data set where I want to predict a binary variable Y.
> I want to do an under sampling by keeping all the 1 and taking just some of
> the 0 such as I'll have 90% of 0 and 10% of 1.

ou haven' t given much detail , buteo thing like  this will take all of the 1's and 10% of the 0's

dfrm[c(rownames(dfrm[dorm$Y==1,]), sample(rownames(dfrm[dfrm$Y==0]), 0.10)) , ]
> Can u help me do that
> Thank u
> 
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