How to Calculate Average CV (Coefficient of variation)?

M

Mark Smith

#1
Can somebody tell me why it is that when determining an average CV you must take the square root of the sum of the squares rather than just the average?
 
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D

Don Winton

#2
Interesting question.

Unfortunately, I can only speculate since my experience is limited. My speculation: If you want the average of the Coefficient of Variation, I do not see any reason why the mean would not work. Normally, CV is used to compare one process with another. If these are running over a period of time, the mean of CV should be an acceptable measure. I would recommend that you ask this question to whoever said the square root of sum of squares is required. Frankly, I do not see it, but I could be missing something.

Regards,
Don

------------------
Just the ramblings of an Old Wizard Warrior.
 
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