Measures of Dispersion | Business Mathematics and Statistics - B Com PDF Download

 Page 1


MEASURES OF 
DISPERSION 
 
Page 2


MEASURES OF 
DISPERSION 
 
DISPERSION 
? Dispersion refers to the variations of the items 
among themselves / around an average. 
? Greater the variation amongst different items of 
a series, the more will be the dispersion. 
? As per Bowley, “Dispersion is a measure of the 
variation of the items”. 
 
 
Page 3


MEASURES OF 
DISPERSION 
 
DISPERSION 
? Dispersion refers to the variations of the items 
among themselves / around an average. 
? Greater the variation amongst different items of 
a series, the more will be the dispersion. 
? As per Bowley, “Dispersion is a measure of the 
variation of the items”. 
 
 
OBJECTIVES OF MEASURING DISPERSION 
? To determine the reliability of an average 
? To compare the variability of two or more series 
? For facilitating the use of other statistical 
measures 
? Basis of Statistical Quality Control 
 
 
Page 4


MEASURES OF 
DISPERSION 
 
DISPERSION 
? Dispersion refers to the variations of the items 
among themselves / around an average. 
? Greater the variation amongst different items of 
a series, the more will be the dispersion. 
? As per Bowley, “Dispersion is a measure of the 
variation of the items”. 
 
 
OBJECTIVES OF MEASURING DISPERSION 
? To determine the reliability of an average 
? To compare the variability of two or more series 
? For facilitating the use of other statistical 
measures 
? Basis of Statistical Quality Control 
 
 
PROPERTIES OF A GOOD MEASURE OF 
DISPERSION 
? Easy to understand 
? Simple to calculate 
? Uniquely defined 
? Based on all observations 
? Not affected by extreme observations 
? Capable of further algebraic treatment 
 
 
Page 5


MEASURES OF 
DISPERSION 
 
DISPERSION 
? Dispersion refers to the variations of the items 
among themselves / around an average. 
? Greater the variation amongst different items of 
a series, the more will be the dispersion. 
? As per Bowley, “Dispersion is a measure of the 
variation of the items”. 
 
 
OBJECTIVES OF MEASURING DISPERSION 
? To determine the reliability of an average 
? To compare the variability of two or more series 
? For facilitating the use of other statistical 
measures 
? Basis of Statistical Quality Control 
 
 
PROPERTIES OF A GOOD MEASURE OF 
DISPERSION 
? Easy to understand 
? Simple to calculate 
? Uniquely defined 
? Based on all observations 
? Not affected by extreme observations 
? Capable of further algebraic treatment 
 
 
MEASURES OF DISPERSION 
Absolute 
Expressed in the 
same units in 
which data is 
expressed 
Ex: Rupees, Kgs, 
Ltr, Km etc. 
Relative 
In the form of ratio 
or percentage, so is 
independent of 
units 
It is also called 
Coefficient of 
Dispersion