The principal focus of the control chart is the attempt to separate special or assignable causes of variation from common causes of variation.What cause of variation can be reduced only by changing the system?
A) Total causes
B) Special or assignable causes
C) Common causes
D) None of the above.

Question

Quizplus · Accepted Answer

Common causes of variation are inherent in the system and cannot be eliminated through process improvement. Only by changing the system itself can common causes of variation be reduced. Special or assignable causes, on the other hand, can be identified and eliminated by process improvement efforts. Total causes is not a recognized category of causes of variation in statistical process control.

The Principal Focus of the Control Chart Is the Attempt