sigma

engineering partnership

Sampling

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:

• Learn about sources of variation
• Stabilise unstable processes
• Centre processes on target
• Reduce variation to tolerable limits
• Maintain stability

As confidence in process capability increases, sampling frequency can be reduced and ultimately eliminated. Deming (1960) is a good text on sampling.

Home page of Inspection and Quality Control

sigma   HOME

engineering partnership

This page last updated 13^th July 2001

Copyright ©2001 A N Cutler