Question
Which measures of dispersion is the most unstable statistic and why?
Solution
It can be observed that the mean derived from the two data sets given as under :
A
|
Scores of individual |
|
|
Individual |
Score |
|
XI |
52 |
|
X2 |
55 |
|
X3 |
50 |
|
X4 |
48 |
|
X5 |
45 |
B
|
Scores of Individual |
|
|
Individual |
Score |
|
X1 |
28 |
|
X2 |
00 |
|
X3 |
98 |
|
X4 |
55 |
|
X5 |
69 |
is same i.e. 50. The highest and the lowest score shown as above table A 55 and 45 respectively. The distribution in table B has a high score of 98 and a low score of zero. The range of first distribution is 10 whereas it is 98 in the second distribution. Although the mean for both the groups is the same, the first group is obviously stable or homogeneous as compared to the distribution of score of the second group which is highly unstable or heterogeneous.
