tree
and
tree.sequence
Objects of class
"tree" are created by the
tree function.
Objects of class
"tree.sequence" are the result of operations
to a tree to make it smaller; they may be made by either
prune.tree
or
shrink.tree.
Generic functions that have methods for class
"tree" are:
[,
browser,
deviance,
identify,
labels,
plot,
predict,
print
,
residuals,
summary,
text.
Generic functions with methods for
"tree.sequence" are:
plot.
The
shrink.tree function produces either an object with class
c("bonzai", "tree")
or with class
c("shrink", "tree.sequence").
The following components must be included in a legitimate
tree object.
Of these, only the
where component has the same length as
the data used to fit the tree object.
row.names of
frame contain the (unique) node numbers that
follow a binary ordering indexed by node depth.
Elements of
frame include
var,
the variable used in the split at each node
(leaf nodes are denoted by the string n, the size of each node,
dev
, the deviance of each node,
yval
, the fitted value of the response at each node,
splits
, a two column matrix of left and right split labels
for each node.
Classification trees have an additional element
yprob,
the matrix containing the class probabilities for each node.
frame corresponding to the leaf node
that each observation falls into.
expression and class
term summarizing the formula.
Used by various methods, but typically not of direct relevance to users.
update(tree).
"tree.sequence" is: