Which one of the following statements is false?
1
Arithmetic mean is used to measure the deviations in calculating standard deviation due to its least squares property
2
Z-Score value of 'X' is the ratio between 'X' divided by mean X
3
The coefficient of variation is calculated as follows: \(\rm\frac{\sigma}{\bar{x}}\) × 100
4
Standard deviation can be equal to zero in some situations.