summary.tree(object)
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.
call
which defines the tree,
which variables in the formula are represented in the tree,
the number of terminal nodes,
the residual deviance,
and the distribution of residuals (regression)
or misclassification error rate (classification).
This function is a method for the generic function for class tree. It can be invoked by calling for an object x of the appropriate class, or directly by calling regardless of the class of the object.
z.auto <- tree(Mileage ~ Weight, car.test.frame) summary(z.auto) # Gives the following output: Regression tree: tree(formula = Mileage ~ Weightt, data = car.test.frame) Number of terminal nodes: 9 Residual mean deviance: 4.289 = 218.7 / 51 Distribution of residuals: Min. 1st Qu. Median Mean 3rd Qu. Max. -3.889 -1.111 0 0 1.083 4.375 z.survey <- tree(market.survey, na.action = na.exclude) summary(z.survey) # Gives the following output: Classification tree: tree(formula = market.survey, na.action = na.omit) Number of terminal nodes: 102 Residual mean deviance: 0.8437 = 554.3 / 657 Misclassification error rate: 0.1805 = 137 / 759