The recipes
package is an alternative method for creating and
preprocessing design matrices that can be used for modeling or
visualization. From
wikipedia:
In statistics, a design matrix (also known as regressor matrix or model matrix) is a matrix of values of explanatory variables of a set of objects, often denoted by X. Each row represents an individual object, with the successive columns corresponding to the variables and their specific values for that object.
While R already has long-standing methods for creating these matrices
(e.g.
formulas
and model.matrix
), there are some limitations to what the existing
infrastructure can
do.
The idea of the recipes
package is to define a recipe or blueprint
that can be used to sequentially define the encodings and preprocessing
of the data (i.e. “feature engineering”). For example, to create a
simple recipe containing only an outcome and predictors and have the
predictors centered and scaled:
library(recipes)
library(mlbench)
data(Sonar)
sonar_rec <- recipe(Class ~ ., data = Sonar) %>%
step_center(all_predictors()) %>%
step_scale(all_predictors())
To install it, use:
install.packages("recipes")
## for development version:
require("devtools")
install_github("tidymodels/recipes")