The target is the ideal value for the population mean. You specify the target when you perform the equivalence test based on your process knowledge.
The mean of the sample is an estimate of the population mean. Therefore, the difference between the sample mean and the target is an estimate of the difference between the population mean and the target.
Because the difference is based on sample data and not on the entire population, you cannot be certain that it equals the difference between the population mean and the target. To assess the precision of the estimate for the population, you can use a confidence interval.If you define your equivalence limits as a product of the target by using the Multiply by target option, the Method table also includes the calculations used to determine the lower and upper equivalence limits for the test.