| Cpm is one
of several indices used to measures Process
Capability. Cpm is called the
Taguchi Capability Index. It combines variability
and distance from the target into one measure
and is closely related to the Taguchi 'Signal
to Noise Ratio' concept:

Where:
|
USL,
LSL |
Upper and Lower
Specification Limits |
|
T |
Target value |
|
σ
|
Process Standard
Deviation |
|
μ
|
Process Mean |
|