lgb.plot.importance function

Plot feature importance as a bar graph

Plot previously calculated feature importance: Gain, Cover and Frequency, as a bar graph.

lgb.plot.importance(
  tree_imp,
  top_n = 10L,
  measure = "Gain",
  left_margin = 10L,
  cex = NULL
)

Arguments

• tree_imp: a data.table returned by lgb.importance.
• top_n: maximal number of top features to include into the plot.
• measure: the name of importance measure to plot, can be "Gain", "Cover" or "Frequency".
• left_margin: (base R barplot) allows to adjust the left margin size to fit feature names.
• cex: (base R barplot) passed as cex.names parameter to barplot. Set a number smaller than 1.0 to make the bar labels smaller than R's default and values greater than 1.0 to make them larger.

Returns

The lgb.plot.importance function creates a barplot

and silently returns a processed data.table with top_n features sorted by defined importance.

Details

The graph represents each feature as a horizontal bar of length proportional to the defined importance of a feature. Features are shown ranked in a decreasing importance order.

Examples

data(agaricus.train, package = "lightgbm")
train <- agaricus.train
dtrain <- lgb.Dataset(train$data, label = train$label)

params <- list(
    objective = "binary"
    , learning_rate = 0.1
    , min_data_in_leaf = 1L
    , min_sum_hessian_in_leaf = 1.0
    , num_threads = 2L
)

model <- lgb.train(
    params = params
    , data = dtrain
    , nrounds = 5L
)

tree_imp <- lgb.importance(model, percentage = TRUE)
lgb.plot.importance(tree_imp, top_n = 5L, measure = "Gain")