Artificial Intelligence / Unit 8 AI 0403 short lesson, about 20 seconds
The Test Drawer
Captions available
The idea
Before any learning begins, part of the data is locked away as a test set — untouched until grading day, because a test row that influenced learning is training data under another name.
In practice
The stall log: rows one through six teach; rows seven and eight wait in the drawer.
Where people slip
Peeking converts test into training silently — the drawer's value is exactly its untouchedness.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Builds on
Something wrong in this lesson? Flag it · Sources for Artificial Intelligence