Statistical Power Calculation

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Power: Two Samples Mean: Hypothesis test

This utility can be used to calculate statistical power gained with given sample size when your aim is to test whether two sample means are significantly different.

Formula used and other details
First Sample mean (μ1) First Sample mean in your study.
Standard Deviation of first Sample mean (SD1) Standard Deviation of first sample mean in your study.
Total Number of participant in first group (N1) Sample size in first group (related to μ1 and SD1). Should be between 1 and 1000000
Second Sample mean (μ2) Second Sample mean in your study.
Standard Deviation of second Sample mean (SD2) Standard Deviation of second sample mean in your study.
Total Number of participant in second group (N2) Sample size in second group (related to μ2 and SD2). Should be between 1 and 1000000
Confidence Level % In percentage. Commonly used values are 95, 99 and 90. Should be between 0.01 to 99.99.
One sided or two sided One tailed or two tailed hypothesis
Power ( 1 - β) =