xgboost (version 0.6-4)

xgb.plot.tree: Plot a boosted tree model

Description

Read a tree model text dump and plot the model.

Usage

xgb.plot.tree(feature_names = NULL, model = NULL, n_first_tree = NULL,
  plot_width = NULL, plot_height = NULL, ...)

Arguments

feature_names

names of each feature as a character vector. Can be extracted from a sparse matrix (see example). If model dump already contains feature names, this argument should be NULL.

model

generated by the xgb.train function. Avoid the creation of a dump file.

n_first_tree

limit the plot to the n first trees. If NULL, all trees of the model are plotted. Performance can be low for huge models.

plot_width

the width of the diagram in pixels.

plot_height

the height of the diagram in pixels.

...

currently not used.

Value

A DiagrammeR of the model.

Details

The content of each node is organised that way:

• feature value;

• cover: the sum of second order gradient of training data classified to the leaf, if it is square loss, this simply corresponds to the number of instances in that branch. Deeper in the tree a node is, lower this metric will be;

• gain: metric the importance of the node in the model.

The function uses GraphViz library for that purpose.

Examples

# NOT RUN {
data(agaricus.train, package='xgboost')

bst <- xgboost(data = agaricus.train$data, label = agaricus.train$label, max_depth = 2, 
               eta = 1, nthread = 2, nrounds = 2,objective = "binary:logistic")

xgb.plot.tree(feature_names = colnames(agaricus.train$data), model = bst)

# }