The value that Minitab uses to compare with the sample mean and specification limits to determine whether to accept a sampled lot or reject a sampled lot from a variables acceptance sampling plan.
For example, suppose you sample lots of filled bottles. Your sample plan calls for randomly sampling 100 of the 1000 bottles in a shipment. The lower and upper specifications for fill volume are 24.5 and 26.7 ounces. Minitab determines the critical distance to be 2.5.
As long as the lot standard deviation is less than the Maximum Standard Deviation (MSD), you should accept the entire lot if:
Both of these criteria must be true or you should reject the entire lot.
The specific calculations depend upon the number of specifications given and whether the standard deviation is known. For more information, see Methods and Formulas.