Process capability — measuring process ability to meet specs.
Metrics:
Formula: Cp = (USL - LSL) / (6 × σ)
Example:
Order fulfillment time:
LSL: 1 day, USL: 5 days
Mean: 3 days, Std Dev: 0.5 days
Cp = (5 - 1) / (6 × 0.5) = 1.33
Cpk = 1.33 (centered)
Interpretation:
- Cp > 1.33: Capable
- Cpk = Cp: Centered
BA use: