yardstick: metrics – R documentation

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metrics

General Function to Estimate Performance

Description

This function estimates one or more common performance estimates depending on the class of truth (see Value below) and returns them in a three column tibble.

Usage

metrics(data, ...)

## S3 method for class 'data.frame'
metrics(data, truth, estimate, ..., options = list(), na_rm = TRUE)

Arguments

`data`	A `data.frame` containing the `truth` and `estimate` columns and any columns specified by `...`.
`...`	A set of unquoted column names or one or more `dplyr` selector functions to choose which variables contain the class probabilities. If `truth` is binary, only 1 column should be selected. Otherwise, there should be as many columns as factor levels of `truth`.
`truth`	The column identifier for the true results (that is `numeric` or `factor`). This should be an unquoted column name although this argument is passed by expression and support quasiquotation (you can unquote column names).
`estimate`	The column identifier for the predicted results (that is also `numeric` or `factor`). As with `truth` this can be specified different ways but the primary method is to use an unquoted variable name.
`options`	A `list` of named options to pass to `pROC::roc()` such as `smooth`. These options should not include `response`, `predictor`, `levels`, `quiet`, or `direction`.
`na_rm`	A `logical` value indicating whether `NA` values should be stripped before the computation proceeds.

Value

A three column tibble.

When truth is a factor, there are rows for accuracy() and the Kappa statistic (kap()).
When truth has two levels and 1 column of class probabilities is passed to ..., there are rows for the two class versions of mn_log_loss() and roc_auc().
When truth has more than two levels and a full set of class probabilities are passed to ..., there are rows for the multiclass version of mn_log_loss() and the Hand Till generalization of roc_auc().
When truth is numeric, there are rows for rmse(), rsq(), and mae().

Examples

# Accuracy and kappa
metrics(two_class_example, truth, predicted)

# Add on multinomal log loss and ROC AUC by specifying class prob columns
metrics(two_class_example, truth, predicted, Class1)

# Regression metrics
metrics(solubility_test, truth = solubility, estimate = prediction)

# Multiclass metrics work, but you cannot specify any averaging
# for roc_auc() besides the default, hand_till. Use the specific function
# if you need more customization
library(dplyr)

hpc_cv %>%
  group_by(Resample) %>%
  metrics(obs, pred, VF:L) %>%
  print(n = 40)

yardstick

Tidy Characterizations of Model Performance

v0.0.8

MIT + file LICENSE

Authors

Max Kuhn [aut], Davis Vaughan [aut, cre], RStudio [cph]

Initial release