In constructing variable control charts,when the population standard deviation is not known we typically use ______.
A)the variance as a measure of dispersion
B)the range as a measure of dispersion
C)the mean as a measure of dispersion
D)the mode as a measure of dispersion

Question

Quizplus · Accepted Answer

When the population standard deviation is not known, we typically use the range (the difference between the largest and smallest value in a sample) as a measure of dispersion. This is because the range provides an estimate of the variability in the data and can be used to calculate the limits for the control chart. However, using the variance (option A) as a measure of dispersion is also possible, but it requires an additional step to estimate the population standard deviation. The mean and mode (options C and D) are measures of central tendency and not measures of dispersion, so they are not suitable for constructing variable control charts.

In Constructing Variable Control Charts,when the Population Standard Deviation Is