vt.tree {aVirtualTwins}

Trees to find Subgroups

Description

vt.tree is a wrapper of VT.tree.class and VT.tree.reg. With parameter tree.type, any of these two class can be used with its own parameter.

Usage

vt.tree(tree.type = "class", vt.difft, sens = ">", threshold = seq(0.5,
  0.8, 0.1), screening = NULL, ...)

Arguments

tree.type

must be a character. "class" for classification tree, "reg" for regression tree.

vt.difft

VT.difft object. Or return of vt.forest function.

sens

must be a character c(">","<"). See VT.tree for details.

threshold

must be numeric. It can be a unique value or a vector. If numeric vector, a list is returned. See VT.tree for details.

screening

must be logical. If TRUE, only varimp variables of VT.object is used to create the tree.

...

rpart() function parameters. Can be used for any tree.type.

Details

See VT.tree, VT.tree.class and VT.tree.reg classes.

Value

VT.tree or a list of VT.tree depending on threshold dimension. See examples.

Examples

data(sepsis)
vt.o <- vt.data(sepsis, "survival", "THERAPY", T)
# inside model :
vt.f <- vt.forest("one", vt.o)
# use classification tree
vt.tr <- vt.tree("class", vt.f, threshold = c(0.01, 0.05))
# return a list
class(vt.tr)
# access one of the tree
tree1 <- vt.tr$tree1
# return infos
# vt.tr$tree1$getInfos()
# vt.tr$tree1$getRules()
# use vt.subgroups tool:
subgroups <- vt.subgroups(vt.tr)