Sample size required to test means dependent samples
The $ES$ is defined as
- $\mu_d$ is the mean of the difference,
- $\sigma_d$ is the standard deviation of the difference.
The formula for determining the sample size required in each group to ensure that the test has a specified power is
- $\alpha$ is the selected level of significance,
- $1-\beta$ is the selected power and
- $ES$ is the effect size.