Question

Consider the following sets of sample data:

A: 20,347, 20,327, 22,117, 21,762, 20,864, 20,102, 21,684, 20,063, 21,728, 21,580, 21,720, 20,920, 21,442, 20,766
B: 3.38, 4.64, 4.09, 3.93, 4.25, 4.63, 4.78, 4.25, 4.46, 2.93, 3.64

Required:
For each of the above sets of sample data, calculate the coefficient of variation, CV.

Answer 1

3.319%

14.13%

Explanation:

A: 20347, 20327, 22117, 21762, 20864, 20102, 21684, 20063, 21728, 21580, 21720, 20920, 21442, 20766

B: 3.38, 4.64, 4.09, 3.93, 4.25, 4.63, 4.78, 4.25, 4.46, 2.93, 3.64

Given the data:

The mean, m = Σx / n

The standard deviation, s = √Σ(x - m)²/ (n-1))

The coefficient of variation is, CV = s / mean

Using calculator to save computation time :

A: 20,347, 20,327, 22,117, 21,762, 20,864, 20,102, 21,684, 20,063, 21,728, 21,580, 21,720, 20,920, 21,442, 20,766

Data A :

Mean, m = 21101.5714

Standard deviation, s = 700.28925

CV = s / m * 100% = 700.28925 / 21101.5714 * 100% = 3.319%

Data B:

Mean = 4.089

Standard deviation, s = 0.5776

CV = 0.5776 / 4.089 * 100% = 14.13%