In the statistical process control methodology, if the variation in the process is due to _____ causes alone, the process is said to be in statistical control.
A) non-random
B) special
C) assignable
D) common

Question

Quizplus · Accepted Answer

Common causes are sources of variation that are inherent in the process and are expected to occur randomly. Therefore, if the variation is due to common causes alone, the process is said to be in statistical control. Non-random causes (choice A), special causes (choice B), and assignable causes (choice C) are all terms used to describe sources of variation that are not inherent in the process and need to be identified and addressed to improve process performance.

In the Statistical Process Control Methodology, If the Variation in the Process