What is the difference between standard deviation and coefficient of variation?

In short, the standard deviation measures how far the average value lies from the mean, whereas the coefficient of variation measures the ratio of the standard deviation to the mean. The coefficient of variation can be useful when comparing data sets with different units or widely different means.

What is the coefficient of variation of a data set?

Its standard deviation is 10 and its average is 100, giving the coefficient of variation as 10 / 100 = 0.1 The data set [1, 5, 6, 8, 10, 40, 65, 88] has still more variability. Its standard deviation is 32.9 and its average is 27.9, giving a coefficient of variation of 32.9 / 27.9 = 1.18

What is a coefficient of variation?

It shows the extent of variability in relation to the mean of the population. The coefficient of variation should be computed only for data measured on scales that have a meaningful zero ( ratio scale) and hence allow relative comparison of two measurements (i.e., division of one measurement by the other).