Find out which predictor variables are actually used in the random forest.
Usage
varUsed(x, by.tree=FALSE, count=TRUE)
Arguments
x
An object of class randomForest.
by.tree
Should the list of variables used be broken down by
trees in the forest?
count
Should the frequencies that variables appear in trees be
returned?
Value
If count=TRUE and {by.tree=FALSE}, a integer vector containing
frequencies that variables are used in the forest. If
by.tree=TRUE, a matrix is returned, breaking down the counts by
tree (each column corresponding to one tree and each row to a variable).
If count=FALSE and by.tree=TRUE, a list of integer
indices is returned giving the variables used in the trees, else if
by.tree=FALSE, a vector of integer indices giving the
variables used in the entire forest.