Minitab cannot calculate the confidence interval (CI) if either of the following two conditions are not met:
represents the pooled variance for the reference periods, and S2TT
represents the pooled variance for the test periods, and both S2RR
are calculated as described in the Pooled variance section, and W
is given by the following:
By default, Minitab calculates the 100(1 - α)% CI for the ratio as follows:
CI = [min(C, ρL), max(C, ρU)]
where t = t1-α,v
– 2, and STR
is calculated as described in the Pooled variance section.
If you select the option to use the 100(1 – 2α)% CI, then the CI is given by the following:
CI = [ρL, ρU]
For a hypothesis of Test mean / reference mean > lower limit, the 100(1 – α)% lower bound is equal to ρL.
For a hypothesis of Test mean / reference mean < upper limit, the 100(1 – α)% upper bound is equal to ρU.
|Mean of the reference periods (for more information, see the section on the Ratio)|
|Mean of the test periods (for more information, see the section on the Ratio)|
|ni||Number of participants in sequence i|
|v||Degrees of freedom|
|α||Significance level for the test (alpha)|
|t1-α,v||Upper 1 – α critical value for a t-distribution with v degrees of freedom|