Evaluation concepts
Recall
An evaluation metric that measures how many actual positive cases the system successfully found.
Recall answers: of all the things the system should have found, how many did it catch? It is important when misses are costly, such as failing to detect unsafe content, missing a relevant document, or overlooking a critical incident.
High recall can come with more false positives. Many production systems tune thresholds based on the downstream workflow: high recall for triage, higher precision for irreversible actions.
Related terms