100(1 – α)% CI
By default, Minitab uses the following formula to calculate the 100(1 – α)% confidence interval (CI) for the difference:
CI = [min(C, Dl), max(C, Du)]
100(1 – 2α)% CI
If you select the option to use the 100(1 – 2 α)% CI, then the CI is given by the following formula:
CI = [Dl, Du]
For a hypotheses of Test mean > target, or Test mean - target > lower limit, the 100(1 – α)% lower bound is equal to DL.
For a hypothesis of Test mean < target, or Test mean - target < upper limit, the 100(1 – α)% upper bound is equal to DU.
|D||Difference between the mean of the test sample and the target value|
| δ1||Lower equivalence limit|
|δ2||Upper equivalence limit|
|v||Degrees of freedom|
|α||Significance level for the test|
|t1 – α, v||Upper 1 – α critical value for a t-distribution with v degrees of freedom|