Glossary · Phase 2 · Math, when you need it
Central limit theorem
Averages of many random values form a bell curve, even when the values themselves don't.
Try it now
Draw 500 samples and check the readout. Close to 68% land within one standard deviation, whatever mean and σ you pick.
Learn it properly
The normal distribution · The bell curve, and why it shows up everywhere. About 25 minutes.
Other terms from the same lesson
- normal distribution: The bell-shaped curve: most values sit near the average, and fewer the further you go.
- z-score: How many standard deviations a value sits above or below the average. A z-score of 2 is unusually high.
Never trained an AI?
Teach a small one to write, right in your browser. It takes about 20 seconds and needs no account.