SubsetAccuracy
Subset accuracy, also known as the exact match ratio, is a metric used in multi-label classification to evaluate how often the predicted set of labels for a given instance exactly matches the true set of labels.
Definition: For a dataset with N instances, each instance i has a true label set Yi and
Interpretation and properties: Subset accuracy is a very strict metric. It rewards perfect predictions per instance
Relation to other metrics: Unlike per-label metrics such as accuracy, precision, recall, and F1, subset accuracy
Considerations: Subset accuracy can be harsh in datasets with many possible labels or imbalanced label distributions.