How To Calculate Statistical Power Analysis

Expert Guide to Statistical Power Analysis

Module A: Introduction & Importance

Statistical power analysis is a crucial aspect of experimental design and data analysis…

Module B: How to Use This Calculator

1. Enter the desired significance level (α).
2. Enter the desired power (1 – β).
3. Enter the expected effect size.
4. Enter the initial sample size (n).
5. Click ‘Calculate’.

Module C: Formula & Methodology

The formula used in this calculator is based on the non-central t-distribution…

Module D: Real-World Examples

Let’s consider three scenarios…

Module E: Data & Statistics

Scenario	α	Power	Effect Size	Sample Size
1	0.05	0.8	0.5	64
2	0.01	0.9	0.3	128
3	0.05	0.95	0.7	25

Module F: Expert Tips

• Always consider the trade-off between α and power.
• Use pilot studies to estimate effect sizes.

Module G: Interactive FAQ

What is the difference between α and β?

α is the probability of rejecting a true null hypothesis (Type I error), while β is the probability of accepting a false null hypothesis (Type II error).

For more information, see UNC’s guide to power analysis and Social Research Methods’ power analysis guide.