Preprocess
Feature engineering time! You need to build a recipe to take care of non-informative but possibly valuable variables such as observation ID or deal with missing values. This is also an opportunity to transform some predictors. Say, normalize numerical features and create dummy variables for categorical ones.
The attrition
dataset and the train
and test
splits you created in the previous exercise are available in your environment.
Cet exercice fait partie du cours
Feature Engineering in R
Instructions
- Normalize all numeric features.
- Impute missing values using the
knn
imputation algorithm. - Create dummy variables for all nominal predictors.
Exercice interactif pratique
Essayez cet exercice en complétant cet exemple de code.
recipe <- recipe(Attrition ~ ., data = train) %>%
update_role(...1, new_role = "ID") %>%
# Normalize all numeric features
___(all_numeric_predictors()) %>%
# Impute missing values using the knn imputation algorithm
___(all_predictors()) %>%
# Create dummy variables for all nominal predictors
___(all_nominal_predictors())
recipe