Guides ยท Science
Statistical Significance Basics
Test differences with simple stats
This guide explains what statistical significance means, how to choose alpha, estimate sample size, avoid peeking, and interpret p-values alongside effect sizes.
- statistical significance
- p-value
- sample size
- alpha
- effect size
Define hypotheses
State null and alternative clearly before testing.
Pick alpha and power
Choose significance level (often 0.05) and plan sample size for desired power.
Avoid peeking
Do not stop early on random swings; use sequential methods if needed.
Interpret carefully
Pair p-values with effect size and confidence intervals; consider practical impact.