Question: In one to two sentences, define recall for a bird classifier evaluated on a development or test set.

Sample answer: Recall is the fraction of all truly bird images in the evaluation set that the classifier labels as bird.

Key points:

• Recall is a fraction or percentage
• It is computed over all actual bird images in the set
• It measures how many of the true birds were found

Rubric: Full credit: states that recall is the fraction or percentage of all true bird images correctly labeled as bird. Partial credit: partially correct but incomplete. No credit: incorrect or unrelated definition.