[R] Plot with CART results

[Terry Therneau]

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With "rpart" we can get several terminals and  draw it in the TREE plot.
Now I am trying to draw a plot like this: x-axis is each terminal's
value, and y-axis is those observe values. Does anyone has idea what
gramma should I use? Thanks in advance.
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It sounds like you want to plot predicted versus observed.
  fit <- rpart(y ~ .....
  plot(predict(fit), y)