Statistical Power Calculation

Home Significance tests Meta-analysis Puzzles About Contact

Power: Z test - One sample sample proportions

This utility can be used to calculate statistical power gained with given sample size when you want to test whether there is significant difference betweeen a sample proportion and known / hypothesised proportion.

Formula used and other details
Number of participant with desired outcome in sample group (S1) Exact Number of successful outcomes in sample group.
Total Number of participant (N1) Sample size in your study. Should be between 1 and 1000000
Known / hypothetical proportion (P) Known / hypothetical proportion (P), against which sample proportion is compared.
Confidence Level % In percentage. Commonly used values are 95, 99 and 90. Should be between 0.01 to 99.99.
One or two sided test One tailed or two tailed test
Power ( 1 - β) =