In the discrete series, when deviations are taken from actual mean, the formula is
Example:
From the following data, compute the value of standard deviations and variance
Suggested answer:
Standard deviation from assumed mean method:
=588/40-(52/40)^2
=14.7-1.69
=13.01
Step 1:
If a = assumed mean, then take the deviations of the items from a and call it d
Step 2:
Multiply each deviation by corresponding frequency amd obtain sigma fd
Step 3:
Multiply each fd by the corresponding d to get fd2 and obtain S fd2.
Step 4:
