Dear S-plus users,
I am running tree regression and smoothing regression using S-plus
V6.1 for windows. I have two questions. One is related to tree
regression, and another is related to smoothing regression:
1)For tree regression, would anyone kindly tell me how to calculate
the explianed variance based on the summary of model fit?
2)For smoothing regression, I tried to use the Spline smoothing to
get a smooth curve. The basic S+ code I used is:
>plot(x, y)
>lines(smooth.spline(x,y,df=3))
Would anyone tell how to add two confidence iterval lines to the
smoothed curve in this situation?
Thanks in advance,
Tao Xin
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