Statistical Power Calculation
Home
Significance tests
Puzzles
About
Contact
Power: Z test - Two independent 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 two independent sample proportions.
Formula used and other details
Number of participant with desired outcome in first group (S1)
Enter positive number between 0 to 1000000
Required
Exact Number of successful outcomes in first group.
Total Number of participant in first group(N1)
Enter positive number between 1 to 1000000
Required
Sample size in first group. Should be between 1 and 1000000
Number of participant with desired outcome in second group (S2).
Enter positive number between 0 to 1000000
Required
Exact number of sucessful outcomes in second group.
Total Number of participant in second group (N2)
Enter positive number between 1 to 1000000
Required
Sample size in second group. Should be between 1 and 1000000
Confidence Level %
Enter positive number between 0.01 to 99.99
Required
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) =