sv_waterfall: SHAP Waterfall Plot

In shapviz: SHAP Visualizations

SHAP Waterfall Plot

Description

Creates a waterfall plot of SHAP values of one observation. If multiple observations are selected, their SHAP values and predictions are averaged.

Usage

sv_waterfall(object, ...)

## Default S3 method:
sv_waterfall(object, ...)

## S3 method for class 'shapviz'
sv_waterfall(
  object,
  row_id = 1L,
  max_display = 10L,
  order_fun = function(s) order(abs(s)),
  fill_colors = c("#f7d13d", "#a52c60"),
  format_shap = getOption("shapviz.format_shap"),
  format_feat = getOption("shapviz.format_feat"),
  contrast = TRUE,
  show_connection = TRUE,
  show_annotation = TRUE,
  annotation_size = 3.2,
  ...
)

## S3 method for class 'mshapviz'
sv_waterfall(
  object,
  row_id = 1L,
  max_display = 10L,
  order_fun = function(s) order(abs(s)),
  fill_colors = c("#f7d13d", "#a52c60"),
  format_shap = getOption("shapviz.format_shap"),
  format_feat = getOption("shapviz.format_feat"),
  contrast = TRUE,
  show_connection = TRUE,
  show_annotation = TRUE,
  annotation_size = 3.2,
  ...
)

Arguments

object	An object of class "(m)shapviz".
...	Arguments passed to ggfittext::geom_fit_text(). For example, size = 9 will use fixed text size in the bars and size = 0 will altogether suppress adding text to the bars.
row_id	Subset of observations to plot, typically a single row number. If more than one row is selected, SHAP values are averaged, and feature values are shown only when they are unique.
max_display	Maximum number of features (with largest absolute SHAP values) should be plotted? If there are more features, they will be collapsed to one feature. Set to Inf to show all features.
order_fun	Function specifying the order of the variables/SHAP values. It maps the vector s of SHAP values to sort indices from 1 to length(s). The default is function(s) order(abs(s)). To plot without sorting, use function(s) 1:length(s) or function(s) length(s):1.
fill_colors	A vector of exactly two fill colors: the first for positive SHAP values, the other for negative ones.
format_shap	Function used to format SHAP values. The default uses the global option shapviz.format_shap, which equals to function(z) prettyNum(z, digits = 3, scientific = FALSE) by default.
format_feat	Function used to format numeric feature values. The default uses the global option shapviz.format_feat, which equals to function(z) prettyNum(z, digits = 3, scientific = FALSE) by default.
contrast	Logical flag that detemines whether to use white text in dark arrows. Default is TRUE.
show_connection	Should connecting lines be shown? Default is TRUE.
show_annotation	Should "f(x)" and "E(f(x))" be plotted? Default is TRUE.
annotation_size	Size of the annotation text (f(x)=... and E(f(x))=...).

Details

f(x) denotes the prediction on the SHAP scale, while E(f(x)) refers to the baseline SHAP value.

Value

An object of class "ggplot" (or "patchwork") representing a waterfall plot.

Methods (by class)

• sv_waterfall(default): Default method.

• sv_waterfall(shapviz): SHAP waterfall plot for an object of class "shapviz".

• sv_waterfall(mshapviz): SHAP waterfall plot for an object of class "mshapviz".

See Also

sv_force()

Examples

dtrain <- xgboost::xgb.DMatrix(
  data.matrix(iris[, -1]), label = iris[, 1], nthread = 1
)
fit <- xgboost::xgb.train(data = dtrain, nrounds = 20, nthread = 1)
x <- shapviz(fit, X_pred = dtrain, X = iris[, -1])
sv_waterfall(x)
sv_waterfall(x, row_id = 123, max_display = 2, size = 9, fill_colors = 4:5)

# Ordered by colnames(x), combined with max_display
sv_waterfall(
  x[, sort(colnames(x))], order_fun = function(s) length(s):1, max_display = 3
)

# Aggregate over all observations with Petal.Length == 1.4
sv_waterfall(x, row_id = x$X$Petal.Length == 1.4)

shapviz documentation built on Sept. 14, 2024, 5:07 p.m.