Question

The Cp statistic is more useful than the Cpk statistic since it can better account for non-centered distributions.

True

False

Answer 1

• If Cp = Cpk, then the process is perfectly centered.
• Because Cpk accounts for centering (where Cp does not), Cpk can never be larger than Cp.
• Both assume a stable process.
• Cpk measures how close a process is performing compared to its specification limits and accounting for the natural variability of the process.
• Larger is better. The larger Cpk is, the less likely it is that any item will be outside the specification limits.

Hence the given statement is false..

Cpk statistics is more useful