learn.howToCalculate

learn.whatIsHeading

Statistical power (1−β) is the probability of correctly detecting a true effect. Power of 0.80 (80%) is the conventional minimum — a 20% chance of missing a real effect (Type II error).

Trin-for-trin guide

1. 1Power increases with: larger n, larger effect size, higher α
2. 2Plan sample size to achieve 80% power before collecting data
3. 3Power = Φ(|d|√(n/2) − z_α)

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