Calculation of Standard Deviation - Discrete Series
There are three methods for calculating standard deviation in discrete series":
a.Actual Mean Methods: It include the following steps
1.Calculate the mean of the series.
2.Find deviations for various items from the mean i ,e, X- s
3.Square the deviations d2 and multiply by the respective frequencies(f) we get fd2.
4. Total the product ( ∑fd2). The apply the formula.
= √∑fd2/ ∑f