☰
Measures of Dispersion
Illustrate the meaning of the term dispersion with examples.
Dispersion is a measure of the variation of the items. According to Prof. C.R. Conn, Dispersion is a measure of the extent to which the individual item vary. The measures of dispersion are required to measures the amount of variation of values about the central values.
Example : Suppose the monthly incomes in rupees of five house holds are as Rs. 4500, 6000, 5500, 3750 and 4700.
The arithmatic mean of income is Rs. 4700. The amount of variation in income is shown by deviations from the central values. In this case the deviation from the arithmean are Rs. 390, 1110, 610, 1140 and 190.
Sponsor Area
In the previous question, calculate the relative measures of variation and indicate the value, which in your opinion is more reliable.
If in the previous question, each worker is given a hike of 10% in wages, how are the mean and standard deviation values affected?
The sum of 10 values is 100 and the sum of their squares is 1090. Find the coefficient of variation.
Calculate the mean deviation about mean and standard deviation for the following distribution:
|
Classes |
Frequencies |
|
20–40 |
3 |
|
40–80 |
6 |
|
80–100 |
20 |
|
100–120 |
12 |
|
120–140 |
9 |
|
50 |
A measure of dispersion is a good .supplement to the central value in understanding a frequency distribution. Comment
Define dispersion.
How many methods are there to calculate dipersion?
Define range.
Define quartile deviation.
How is coefficient of quartile deviation calculated?
Sponsor Area
Sponsor Area