fitted model object of class
tree.
This is assumed to be the result of some function that produces
an object with the same named
components as that returned by the
tree() function.
OPTIONAL ARGUMENTS:
label
label for the partitions.
By default, the fitted value of the response variable is used to label
each partition of the tree.
For classification trees, the supplied
label must be a column name of
tree$yprob.
add
logical; if
TRUE, the partition or step function is added to the current plot.
ordinate
character string that specifies which variable is plotted on the
ordinate axis. Default is the name of the second variable.
...
other arguments to be passed to the
plot function.
SIDE EFFECTS:
a plot of the relationship y = f(x)
(one-variable tree) or y = f(x1, x2) (two-variable tree).
The function stops if
tree consists of more than
two predictors or if the predictors are factors.
DETAILS:
For a single predictor, y=f(x) is a step function.
For two predictors, the prediction space is carved into partitions,
displaying the fitted values in each.