Create a Validation SetSource:
validation_split() takes a single random sample (without replacement) of
the original data set to be used for analysis. All other data points are
added to the assessment set (to be used as the validation set).
validation_time_split() does the same, but takes the first
for training, instead of a random selection.
group_validation_split() creates splits of the data based
on some grouping variable, so that all data in a "group" is assigned to
the same split.
validation_split(data, prop = 3/4, strata = NULL, breaks = 4, pool = 0.1, ...) validation_time_split(data, prop = 3/4, lag = 0, ...) group_validation_split(data, group, prop = 3/4, ..., strata = NULL, pool = 0.1)
A data frame.
The proportion of data to be retained for modeling/analysis.
A variable in
data(single character or name) used to conduct stratified sampling. When not
NULL, each resample is created within the stratification variable. Numeric
strataare binned into quartiles.
A single number giving the number of bins desired to stratify a numeric stratification variable.
A proportion of data used to determine if a particular group is too small and should be pooled into another group. We do not recommend decreasing this argument below its default of 0.1 because of the dangers of stratifying groups that are too small.
Not currently used.
A value to include a lag between the assessment and analysis set. This is useful if lagged predictors will be used during training and testing.
A variable in
data(single character or name) used for grouping observations with the same value to either the analysis or assessment set within a fold.
An tibble with classes
data.frame. The results include a column for the data split objects
and a column called
id that has a character string with the resample
strata argument, the random sampling is conducted
within the stratification variable. This can help ensure that the
resamples have equivalent proportions as the original data set. For
a categorical variable, sampling is conducted separately within each class.
For a numeric stratification variable,
strata is binned into quartiles,
which are then used to stratify. Strata below 10% of the total are
pooled together; see
make_strata() for more details.
validation_split(mtcars, prop = .9) #> # Validation Set Split (0.9/0.1) #> # A tibble: 1 × 2 #> splits id #> <list> <chr> #> 1 <split [28/4]> validation data(drinks, package = "modeldata") validation_time_split(drinks) #> # Validation Set Split (0.75/0.25) #> # A tibble: 1 × 2 #> splits id #> <list> <chr> #> 1 <split [231/78]> validation group_validation_split(mtcars, cyl) #> # Group Validation Set Split (0.75/0.25) #> # A tibble: 1 × 2 #> splits id #> <list> <chr> #> 1 <split [21/11]> validation