Benchmark Z statistics for between/within capability are calculated by finding the Z value using the standard normal (0,1) distribution for the corresponding statistics.
|LSL||Lower specification limit|
|USL||Upper specification limit|
|Φ (X) ||Cumulative distribution function (CDF) of a standard normal distribution|
|Φ-1 (X)||Inverse CDF of a standard normal distribution|
|Between/within standard deviation|