A moving range (MR) chart is appropriate to monitor variation when every single item is being inspected (n = 1) since the range (R) cannot be calculated.

Question

Quizplus · Accepted Answer

A moving range (MR) chart is used to monitor the variation in a process where the sample size is one (n = 1) and the range (R) cannot be calculated. Instead, the MR chart calculates the difference between successive data points. Therefore, it is appropriate to use an MR chart when every single item is being inspected.

A Moving Range (MR) Chart Is Appropriate to Monitor Variation