#decision-threshold

Question 1: Single choice

A defect detector flags an item if its score is $t$ or higher. On a fixed validation set, $t$ is raised from 0.4 to 0.7. Which statement must hold?

Recall cannot rise, because every item flagged at 0.7 was also flagged at 0.41
Precision must rise, because the alerts that remain are the more confident ones2
Recall must rise, because the model is now more certain about each flagged item3
Nothing changes, because the predicted scores stay the same4