Workhorse function for computing conditioning sets. Not typically needed by users.

Source: R/phi_interval_funs.R

Returns the interval for phi such that Tree(y'(phi,nu)) contains the set of regions induced by branch branch. An rpart object built with model=TRUE must be provided. This function shouldn't be needed by most users (it is called internally by branchInference), but is needed to reproduce our paper simulations.

getInterval(tree, nu, branch, sib = FALSE, grow = FALSE, prune = FALSE)

Arguments

tree

An rpart object. Must have been built with model=TRUE argument.
nu

The vector that defines the parameter nu^T mu.
branch

A vector of strings specifying the branch.
sib

If you are doing inference and nu=nu_sib, this takes advantage of some computational speedups!
grow

Set this to true if you only want to compute S_grow (ignore cost complexity pruning).
prune

Set this to true if you only want to see what gets REMOVED from S_grow during pruning

Value

an object of class Interval that defines the set S.

Examples

data(blsdata, package="treevalues")
bls.tree <-rpart::rpart(kcal24h0~hunger+disinhibition+resteating+rrvfood+liking+wanting,
      model = TRUE, data = blsdata, cp=0.02)
branch <- getBranch(bls.tree, 2)
left_child <- getRegion(bls.tree,2)
right_child <- getRegion(bls.tree,3)
nu_sib <- left_child/sum(left_child) -  right_child/sum(right_child)
S_sib <- getInterval(bls.tree, nu_sib,branch)
S_sib

#> Object of class Intervals
#> 2 intervals over R:
#> (-Inf, -980.709890684641)
#> (1591.88198272855, Inf)
branchInference(bls.tree, branch, type="sib")$condset

#> Object of class Intervals
#> 2 intervals over R:
#> (-Inf, -980.709890684641)
#> (1591.88198272855, Inf)