Glossary · Phase 2 · Math, when you need it
Z-score
How many standard deviations a value sits above or below the average. A z-score of 2 is unusually high.
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
- central limit theorem: Averages of many random values form a bell curve, even when the values themselves don't.
- normal distribution: The bell-shaped curve: most values sit near the average, and fewer the further you go.
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