Sample Size Determination

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Two Samples Proportions: Hypothesis test

This utility can be used to calculate required sample size when your aim is to test whether two sample proportions are significantly different.

Formula used and other details
Your guesstimate of first Sample Proportion (P1) In Percentage. Approxiate estimate of first Sample proportion based on previous studies / pilot studies etc. Should be between 0.01 and 99.99.
Your guesstimate of second Sample proportion (P2) In Percentage. Approxiate estimate of second Sample proportion based on previous studies / pilot studies etc. Should be between 0.01 and 99.99.
Ratio of Sample Size in two Groups (N2 / N1) Sample Size in Group 2 / Saple Size in Group 1
Confidence Level % In percentage. Commonly used values are 95, 99 and 90. Should be between 0.01 to 99.99.
Power ( 1 - β) In Percentage. Should be between 0.001 to 99.999. Common values are 80 % and 90 %
One sided or two sided One tailed or two tailed hypothesis
Sample Size Required =