Glossary · Phase 2 · Math, when you need it
Null hypothesis
The boring explanation you try to rule out: "there's no real difference, it's just chance".
Learn it properly
A/B tests and significance · Tell a real lift from noise. About 30 minutes.
Other terms from the same lesson
- Bonferroni correction: When you run many tests, divide the 0.05 cutoff by how many you ran, so chance alone doesn't hand you a fake winner.
- statistical power: The chance a test spots a real difference when one exists. More data gives more power.
- statistical significance: Evidence that a difference you measured (say, in an A/B test) is probably real, not luck.