Grading Day
This video presents the same text shown beside it, spoken and on screen. It adds nothing the text does not say.
State
A learned predictor is graded on examples it has never seen — the training score measures memory, and only the test score measures what was learned about the world.
Show
Accuracy is the share of predictions that are right; the share that matters is the drawer's.
Watch for
Perfect training scores are cheap — a learner can always get them by memorizing.