Coefficient of Variation

before proceding, if you have not read  Way of expressing precision  i sugest you read it it will give you more understanding of what we duscuss hear.

Standard deviation is the correct method of measuring dispersion. The expression are in the form of unit in which original data is collected. Using goat as an example, standard deviation of the goat it length is different from the standard deviation of the weight of the goat. To be able to share proper similarity of the two, there is need of relative measure conversion. The relative measure of this dispersion is called coefficient of variation.

Mathematically

                 S

C.V    =  ——-   x 100

              ×

S = standard deviation

 ×= means

Standard Deviation of Means

This is also called standard error of means (SEM).

Mathematically

                 S

_____________________

SEM =  √N

S = standard deviation

N = number of observation

Please take note that if the sample collected for the measurement is less than 10, then use n – 1 but if it is more than 10 the use n.