Linear Combination FilterSource:
step_lincomb creates a specification of a recipe
step that will potentially remove numeric variables that have
linear combinations between them.
step_lincomb( recipe, ..., role = NA, trained = FALSE, max_steps = 5, removals = NULL, skip = FALSE, id = rand_id("lincomb") )
A recipe object. The step will be added to the sequence of operations for this recipe.
One or more selector functions to choose variables for this step. See
selections()for more details.
Not used by this step since no new variables are created.
A logical to indicate if the quantities for preprocessing have been estimated.
The number of times to apply the algorithm.
A character string that contains the names of columns that should be removed. These values are not determined until
A logical. Should the step be skipped when the recipe is baked by
bake()? While all operations are baked when
prep()is run, some operations may not be able to be conducted on new data (e.g. processing the outcome variable(s)). Care should be taken when using
skip = TRUEas it may affect the computations for subsequent operations.
A character string that is unique to this step to identify it.
An updated version of
recipe with the new step added to the
sequence of any existing operations.
This step can potentially remove columns from the data set. This may cause issues for subsequent steps in your recipe if the missing columns are specifically referenced by name. To avoid this, see the advice in the Tips for saving recipes and filtering columns section of selections.
This step finds exact linear combinations between two
or more variables and recommends which column(s) should be
removed to resolve the issue. This algorithm may need to be
applied multiple times (as defined by
tidy() this step, a tibble with column
terms (the columns that will be removed) is returned.
Other variable filter steps:
data(biomass, package = "modeldata") biomass$new_1 <- with( biomass, .1 * carbon - .2 * hydrogen + .6 * sulfur ) biomass$new_2 <- with( biomass, .5 * carbon - .2 * oxygen + .6 * nitrogen ) biomass_tr <- biomass[biomass$dataset == "Training", ] biomass_te <- biomass[biomass$dataset == "Testing", ] rec <- recipe(HHV ~ carbon + hydrogen + oxygen + nitrogen + sulfur + new_1 + new_2, data = biomass_tr ) lincomb_filter <- rec %>% step_lincomb(all_numeric_predictors()) lincomb_filter_trained <- prep(lincomb_filter, training = biomass_tr) lincomb_filter_trained #> #> ── Recipe ──────────────────────────────────────────────────────────────── #> #> ── Inputs #> Number of variables by role #> outcome: 1 #> predictor: 7 #> #> ── Training information #> Training data contained 456 data points and no incomplete rows. #> #> ── Operations #> • Linear combination filter removed: new_1, new_2 | Trained tidy(lincomb_filter, number = 1) #> # A tibble: 1 × 2 #> terms id #> <chr> <chr> #> 1 all_numeric_predictors() lincomb_IeIAm tidy(lincomb_filter_trained, number = 1) #> # A tibble: 2 × 2 #> terms id #> <chr> <chr> #> 1 new_1 lincomb_IeIAm #> 2 new_2 lincomb_IeIAm