.annotation_spec_set.AnnotationSpec
The annotation spec of the label for which
the precision-recall curve calculated. If this
field is empty, that means the precision-recall
curve is an aggregate curve for all labels.
area_under_curve
float
Area under the precision-recall curve. Not to
be confused with area under a receiver operating
characteristic (ROC) curve.
confidence_metrics_entries
Sequence[.evaluation.PrCurve.ConfidenceMetricsEntry]
Entries that make up the precision-recall graph. Each entry
is a "point" on the graph drawn for a different
confidence_threshold.