 |
| Summary |
|
- The mean deviation (M.D) of a statistical data is defined as the arithmetic mean of the numerical values of the deviations of the items from some average.
|
| |
- For an individual series,
|
| |
 |
| |
- For a frequency distribution,
|
| |
 |
| |
|
|
| |
- If M.D is calculated about mean, then it is written as M.D (x).
|
| |
 |
| |
- The standard deviation of a statistical data is defined as the positive square root of the A.M of the squared deviations of items from the A.M. of the series under consideration.
|
| |
- For an individual series,
|
| |
 |
| |
- For a frequency distribution,
|
| |
 |
| |
 |
| |
|
|
| |
- Coefficient of variation (C.V)
|
| |
- Let s1
and s2 be the
S.D of the two groups containing n1 and n2
items respectively. Let
 and  be their respective A.M. Let x and
s be the A.M
and S.D of the combined group respectively.
|
| |
 |
| |
