getObservations function

Get Observations Falling into Each Node

This function determines which observations from a given dataset fall into which nodes of a tree, based on a tree structure defined in treeData. The treeData object must include iteration, treeNum, var, and splitValue columns.

getObservations(data, treeData)

Arguments

• data: A data frame used to build BART model.
• treeData: A data frame representing the tree structure, including the necessary columns iteration, treeNum, var, and splitValue.

Returns

A modified version of treeData that includes two new columns: obsNode and noObs. obsNode lists the observations falling into each node, and noObs provides the count of observations for each node.

Examples

data("tree_data_example")
# Create Terminal Column
tree_data_example <- transform(tree_data_example,
                              terminal = ifelse(is.na(var),
                              TRUE,
                               FALSE))
# Create Split Value Column
tree_data_example <- transform(tree_data_example,
                               splitValue = ifelse(terminal == FALSE,
                               value,
                               NA_integer_))
# get the observations
getObservations(data = input_data, treeData = tree_data_example)