Margin of Error
Shows how far a measured percentage could be from the true value.
MoE = 1.96 × √(p(1 − p) ÷ n)
Worked example: p = 0.5 and n = 100. 1.96 × √(0.25 ÷ 100) = 0.098, or ±9.8%.
Why it matters
Small samples give uncertain results, and this helps you avoid overclaiming.
How to use it
- Report it next to your percentage.
- Collect more people to narrow it.
- Treat overlapping ranges with caution.
Example
50% from 100 people has a margin of about ±9.8%.