Plot the Partitions of a simple Tree Model

Usage

partition.tree(tree, label="yval", add=F, ordvars, ...)

Description

This can be used with a regression or classification tree containing one or two continuous predictors (only).

If the tree contains one predictor, the predicted value (a regression tree) or the probability of the first class (a classification tree) is plotted against the predictor over its range in the training set.

If the tree contains two predictors, a plot is made of the space covered by those two predictors and the partition made by the tree is superimposed.

Value

None.

Author(s)

B.D. Ripley

See Also

tree

Examples

data(iris)
ir.tr <- tree(Species ~., iris)
ir.tr
ir.tr1 <- snip.tree(ir.tr, nodes = c(12, 7))
summary(ir.tr1)
par(pty="s")
plot(iris[, 3],iris[, 4], type="n",
   xlab="petal length", ylab="petal width")
text(iris[, 3], iris[, 4], c("s", "c", "v")[iris[, 5]])
par(cex=1.5)
partition.tree(ir.tr1, add=T, cex=1.5)
par(cex=1)


[Package Contents]