R yardstick roc_auc 接收者操作曲線下麵積

roc_auc(data, ...)

# S3 method for data.frame
roc_auc(
  data,
  truth,
  ...,
  estimator = NULL,
  na_rm = TRUE,
  event_level = yardstick_event_level(),
  case_weights = NULL,
  options = list()
)

roc_auc_vec(
  truth,
  estimate,
  estimator = NULL,
  na_rm = TRUE,
  event_level = yardstick_event_level(),
  case_weights = NULL,
  options = list(),
  ...
)

roc_curve() 用於計算完整的 ROC 曲線。

其他類概率指標：average_precision() , brier_class() , classification_cost() , gain_capture() , mn_log_loss() , pr_auc() , roc_aunp() , roc_aunu()

# ---------------------------------------------------------------------------
# Two class example

# `truth` is a 2 level factor. The first level is `"Class1"`, which is the
# "event of interest" by default in yardstick. See the Relevant Level
# section above.
data(two_class_example)

# Binary metrics using class probabilities take a factor `truth` column,
# and a single class probability column containing the probabilities of
# the event of interest. Here, since `"Class1"` is the first level of
# `"truth"`, it is the event of interest and we pass in probabilities for it.
roc_auc(two_class_example, truth, Class1)
#> # A tibble: 1 × 3
#>   .metric .estimator .estimate
#>   <chr>   <chr>          <dbl>
#> 1 roc_auc binary         0.939

# ---------------------------------------------------------------------------
# Multiclass example

# `obs` is a 4 level factor. The first level is `"VF"`, which is the
# "event of interest" by default in yardstick. See the Relevant Level
# section above.
data(hpc_cv)

# You can use the col1:colN tidyselect syntax
library(dplyr)
hpc_cv %>%
  filter(Resample == "Fold01") %>%
  roc_auc(obs, VF:L)
#> # A tibble: 1 × 3
#>   .metric .estimator .estimate
#>   <chr>   <chr>          <dbl>
#> 1 roc_auc hand_till      0.813

# Change the first level of `obs` from `"VF"` to `"M"` to alter the
# event of interest. The class probability columns should be supplied
# in the same order as the levels.
hpc_cv %>%
  filter(Resample == "Fold01") %>%
  mutate(obs = relevel(obs, "M")) %>%
  roc_auc(obs, M, VF:L)
#> # A tibble: 1 × 3
#>   .metric .estimator .estimate
#>   <chr>   <chr>          <dbl>
#> 1 roc_auc hand_till      0.813

# Groups are respected
hpc_cv %>%
  group_by(Resample) %>%
  roc_auc(obs, VF:L)
#> # A tibble: 10 × 4
#>    Resample .metric .estimator .estimate
#>    <chr>    <chr>   <chr>          <dbl>
#>  1 Fold01   roc_auc hand_till      0.813
#>  2 Fold02   roc_auc hand_till      0.817
#>  3 Fold03   roc_auc hand_till      0.869
#>  4 Fold04   roc_auc hand_till      0.849
#>  5 Fold05   roc_auc hand_till      0.811
#>  6 Fold06   roc_auc hand_till      0.836
#>  7 Fold07   roc_auc hand_till      0.825
#>  8 Fold08   roc_auc hand_till      0.846
#>  9 Fold09   roc_auc hand_till      0.828
#> 10 Fold10   roc_auc hand_till      0.812

# Weighted macro averaging
hpc_cv %>%
  group_by(Resample) %>%
  roc_auc(obs, VF:L, estimator = "macro_weighted")
#> # A tibble: 10 × 4
#>    Resample .metric .estimator     .estimate
#>    <chr>    <chr>   <chr>              <dbl>
#>  1 Fold01   roc_auc macro_weighted     0.880
#>  2 Fold02   roc_auc macro_weighted     0.873
#>  3 Fold03   roc_auc macro_weighted     0.906
#>  4 Fold04   roc_auc macro_weighted     0.867
#>  5 Fold05   roc_auc macro_weighted     0.866
#>  6 Fold06   roc_auc macro_weighted     0.865
#>  7 Fold07   roc_auc macro_weighted     0.868
#>  8 Fold08   roc_auc macro_weighted     0.865
#>  9 Fold09   roc_auc macro_weighted     0.841
#> 10 Fold10   roc_auc macro_weighted     0.869

# Vector version
# Supply a matrix of class probabilities
fold1 <- hpc_cv %>%
  filter(Resample == "Fold01")

roc_auc_vec(
   truth = fold1$obs,
   matrix(
     c(fold1$VF, fold1$F, fold1$M, fold1$L),
     ncol = 4
   )
)
#> [1] 0.8131924