On a control chart,how many successive data points on an increasing or decreasing line require an investigation for cause of progressive change?
A)7 or more
B)5 or more
C)4 or more
D)3 or more

Question

Quizplus · Accepted Answer

In control chart analysis, a rule of thumb is that 7 or more successive data points on an increasing or decreasing line indicate a non-random trend that requires investigation for a cause of progressive change. This is known as a "run" and suggests a potential process shift.

On a Control Chart,how Many Successive Data Points on an Increasing