Inspection demands that either all or none of the manufactured items be sampled. However, if data collection is being used for process improvement through variation reduction, a representative subset of production can be sampled in order to:
As confidence in process capability increases, sampling frequency can be reduced and ultimately eliminated. Deming (1960) is a good text on sampling.
This page last updated 13th July 2001
Copyright ©2001 A N Cutler