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## ----setup, include=FALSE-----------------------------------------------------
knitr::opts_chunk$set(
message = FALSE,
digits = 3,
collapse = TRUE,
comment = "#>"
)
options(digits = 3)
library(recipes)
## ----iris-base-rec------------------------------------------------------------
library(recipes)
# make a copy for use below
iris <- iris %>% mutate(original = Species)
iris_rec <- recipe( ~ ., data = iris)
summary(iris_rec)
## ----iris-ref-cell------------------------------------------------------------
ref_cell <-
iris_rec %>%
step_dummy(Species) %>%
prep(training = iris)
summary(ref_cell)
# Get a row for each factor level
bake(ref_cell, new_data = NULL, original, starts_with("Species")) %>% distinct()
## ----defaults-----------------------------------------------------------------
param <- getOption("contrasts")
param
## ----iris-helmert-------------------------------------------------------------
# change it:
go_helmert <- param
go_helmert["unordered"] <- "contr.helmert"
options(contrasts = go_helmert)
# now make dummy variables with new parameterization
helmert <-
iris_rec %>%
step_dummy(Species) %>%
prep(training = iris)
summary(helmert)
bake(helmert, new_data = NULL, original, starts_with("Species")) %>% distinct()
# Yuk; go back to the original method
options(contrasts = param)
## ----iris-2int----------------------------------------------------------------
iris_int <-
iris_rec %>%
step_interact( ~ Sepal.Width:Sepal.Length) %>%
prep(training = iris)
summary(iris_int)
## ----mm-int-------------------------------------------------------------------
model.matrix(~ Species*Sepal.Length, data = iris) %>%
as.data.frame() %>%
# show a few specific rows
slice(c(1, 51, 101)) %>%
as.data.frame()
## ----nope, eval = FALSE-------------------------------------------------------
# # Must I do this?
# iris_rec %>%
# step_interact( ~ Species_versicolor:Sepal.Length +
# Species_virginica:Sepal.Length)
## ----iris-sel-----------------------------------------------------------------
iris_int <-
iris_rec %>%
step_dummy(Species) %>%
step_interact( ~ starts_with("Species"):Sepal.Length) %>%
prep(training = iris)
summary(iris_int)
## ----sel-input, eval = FALSE--------------------------------------------------
# starts_with("Species")
## ----sel-output, eval = FALSE-------------------------------------------------
# (Species_versicolor + Species_virginica)
## ----int-form-----------------------------------------------------------------
iris_int
## ----iris-dont----------------------------------------------------------------
iris_int <-
iris_rec %>%
step_interact( ~ Species:Sepal.Length) %>%
prep(training = iris)
summary(iris_int)
## ----one-hot------------------------------------------------------------------
iris_rec %>%
step_dummy(Species, one_hot = TRUE) %>%
prep(training = iris) %>%
bake(original, new_data = NULL, starts_with("Species")) %>%
distinct()
## ----one-hot-two--------------------------------------------------------------
hot_reference <-
iris_rec %>%
step_dummy(Species, one_hot = TRUE) %>%
prep(training = iris) %>%
bake(original, new_data = NULL, starts_with("Species")) %>%
distinct()
hot_reference
# from above
options(contrasts = go_helmert)
hot_helmert <-
iris_rec %>%
step_dummy(Species, one_hot = TRUE) %>%
prep(training = iris) %>%
bake(original, new_data = NULL, starts_with("Species")) %>%
distinct()
hot_helmert
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