Process performance indices | Formulas and tables | Quality Advisor

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Process performance indices

Process performance indices use sigma of the individuals .

Pp

Pp for one-sided specifications

If you are using one sided specifications, use the following formulas to determine the Cp:

Upper specification:

Lower specification:

Ppk

Where:

Zmin is the smaller of Z_upper and Z_lower.

Using sigma of the individuals:

z upper formula

z lower formula

Pr