DALEXtra (version 2.0)

explain_tidymodels: Create explainer from your tidymodels workflow.

Description

DALEX is designed to work with various black-box models like tree ensembles, linear models, neural networks etc. Unfortunately R packages that create such models are very inconsistent. Different tools use different interfaces to train, validate and use models. One of those tools, which is one of the most popular one is tidymodels package. We would like to present dedicated explain function for it.

Usage

explain_tidymodels(
  model,
  data = NULL,
  y = NULL,
  weights = NULL,
  predict_function = NULL,
  residual_function = NULL,
  ...,
  label = NULL,
  verbose = TRUE,
  precalculate = TRUE,
  colorize = TRUE,
  model_info = NULL,
  type = NULL
)

Arguments

model

object - a fitted workflow created with mlr3.

data

data.frame or matrix - data that was used for fitting. Data should be passed without target column (this shall be provided as the y argument). NOTE: If target variable is present in the data, some of the functionalities my not work properly. Tibble will be converted into data.frame

y

numeric vector with outputs / scores. If provided then it shall have the same size as data

weights

numeric vector with sampling weights. By default it's NULL. If provided then it shall have the same length as data

predict_function

function that takes two arguments: model and new data and returns numeric vector with predictions

residual_function

function that takes three arguments: model, data and response vector y. It should return a numeric vector with model residuals for given data. If not provided, response residuals (\(y-\hat{y}\)) are calculated.

...

other parameters

label

character - the name of the model. By default it's extracted from the 'class' attribute of the model

verbose

if TRUE (default) then diagnostic messages will be printed.

precalculate

if TRUE (default) then 'predicted_values' and 'residuals' are calculated when explainer is created.

colorize

if TRUE (default) then WARNINGS, ERRORS and NOTES are colorized. Will work only in the R console.

model_info

a named list (package, version, type) containg information about model. If NULL, DALEX will seek for information on it's own.

type

type of a model, either classification or regression. If not specified then type will be extracted from model_info.

Value

explainer object (explain) ready to work with DALEX

Examples

# NOT RUN {
library("DALEXtra")
library("tidymodels")
library("recipes")
data <- titanic_imputed
data$survived <- as.factor(data$survived)
rec <- recipe(survived ~ ., data = data) %>%
       step_normalize(fare)
model <- decision_tree(tree_depth = 25) %>%
         set_engine("rpart") %>%
         set_mode("classification")

wflow <- workflow() %>%
         add_recipe(rec) %>%
         add_model(model)


model_fitted <- wflow %>%
                fit(data = data)

explain_tidymodels(model_fitted, data = titanic_imputed, y = titanic_imputed$survived)


# }