Diagrammatic Presentation of Data
One-dimensional – Bar diagrams
Two-dimensional – Rectangles and squares
Three-dimensional - cubes, cylinders ,spheres
Pictograms and cartograms
One Dimensional Diagrams
Line Diagram
Height of each line indicates the value of an
item measured
45
30
20
Simple Bar Diagrams
•
•
•
•
Shows a width or column
Each bar has an equal width but unequal length
Advantage-simple,popular
Limitation-can display only one category of data
Production of an item X for three years
10
8
6
III year
4
II year
I year
2
0
1
2
3
Multiple Bars
• Two or more interrelated series of data are
depicted
• Comparison can be made
Example-performance of boys and girls in an
examination
Number of skilled,unskilled and semiskilled workers in a factory for a couple of years
5
4.5
4
3.5
3
Series 1
2.5
Series 2
2
Series 3
1.5
1
0.5
0
1998
1999
2000
2001
Subdivided or Component Bar
Diagram
Components of revenue expenditure of
Government of India
18
16
14
Othes
12
Grants to states & Union
Territories
10
8
Major subsidies
6
Defence expenditure
4
2
0
1995-96
1999-2000 2003-2004 2008-2009
• Use different colours or shades
• Should be accompanied by a key
• Should not be used for too many components
• Very suitable mode of presenting data on
enrolment of students by the type of courses
such as MA,M.Com.,M.Sc.,MBA, and so on
Draw a subdivided/% bar diagram for the
following data pertaining to the monthly
expenditure of two families
Item of Expenditure
Expenditure in Rupees
Family A
1000
Family B
1600
Clothing
500
800
Rent
800
1000
Education
400
800
Recreation
200
500
Miscellaneous
100
300
Food
Item of
Expenditure
Family A
Rs
%
C%
Family B
Rs
%
C%
Food
1000 33.3 33.3 1600 32 32
Clothing
500 16.7 50
Rent
800 26.7 76.7 1000 20 68
Education
400 13.3 90
Recreation
200 6.7
Miscellaneous 100 3.3
Total
3000
800 16 48
800 16 84
96.7 500 10 94
100
300 6
5000
100
120
100
80
Misc
Recreation
60
Education
Rent
Clothing
40
Food
20
0
Family A
Family B
Broken Bars
• Wide variations in data like some values may
be very large while others extremely small
• Larger bars may be broken
Example
Consider the following data pertaining to the
number of students enrolled in certain faculties
in a university
Faculty
Arts
Number of Students
1500
Science
2000
Commerce
Management
6800
500
7000
2000
1500
1000
500
Arts
Science Commerce Management
Deviation Bar Diagrams
• Shows both positive and negative values
Example
The following data relates to rates of change in
agricultural production for a few years
Year
Percent Change
1996-97
9.3
1997-98
-6.1
1998-99
7.4
1999-2000
-2.2
Percent Change
12
10
8
6
4
2
Percent Change
0
-2
-4
-6
-8
1996-97
1997-98
1998-99
1999-2000
Duo-directional Bar Diagram
• A diagram on both sides of the axis of X
• One component is shown above the
horizontal line while the other is shown
below
• The two components taken together give the
total value of the item displayed
Suppose we have the following data
for two years
Items
1998-99
1999-2000
Total earnings
100
80
Cost of production
60
55
Net Income
40
25
60
50
40
30
20
10
0
10
20
30
40
Sliding Bar Diagram
• Based on percentages
• Can be shown horizontally or vertically
Results of the B.Com. Examination of Three
colleges Affiliated to a certain university
College
Pass
Fail
A
60
40
B
75
25
C
80
20
college C
College B
Fail
Fail
Pass
Pass
College A
Fail
Pass
40 30 20 10 0 10 20 30 40 50 60 70 80 90
Pyramid Diagram
• Suitable to present data on population,
occupation, education and so forth
Draw a pyramid diagram for the following data
pertaining to the inhabitants of a locality
Age Group Male
Female
Total
0-20
25
23
48
20-40
20
18
38
40-60
15
15
30
60-80
10
8
18
80+
5
3
8
Male
Female
35 30 25 20 15 10 5 0 5 10 15 20 25 30 35
Two-Dimensional Diagrams
• Rectangular Diagrams
To compare values of different items in two or
more situations
Given below are the data related to firms A and
B. Show by rectangular diagram the
comparison of cost and profit per unit in the
two firms
Items
Firm A
Firm B
Raw material cost
10,000
7,000
Labour cost
7,000
3,000
Other overhead expenses
4,000
1,500
Miscellaneous expenses
3,000
500
Total cost
24,000
12,000
Total revenue
30,000
18,300
Profit
6,000
6,300
No.of units produced and sold 1,200
900
• Calculate per unit cost and revenue per unit
Firm A
Firm B
8.34
5.83
3.33
2.5
20
25
5
7.78
3.33
1.67
0.55
13.33
20.33
7
Length of rectangle = total revenue /output
Width=respective outputs
30
25
20
Profit
Misc.expenses
15
Overhead expenses
Labour cost
10
Raw material cost
5
0
1200 units Firm A
900 units Firm B
Square Diagrams
• Length and width are of the same dimension.
• The square roots of the figures need to be
calculated and taken as the dimension
Consider
Year
Production of Food grains
1950-51
1960-61
1970-71
1980-81
1990-91
50.8
82
108.4
129.6
176.4
Square root
7.12
9.06
10.41
11.38
13.28
Circular or Pie diagrams
• Angular sector diagram
• Largest sector is given at the top and
others in the clockwise sense
• Descriptive label should be given
• Less effective than bar diagrams
• More than five or six categories would
confuse to differentiate the relative
values
Items
Food
Clothing
Housing
Fuel and
Lighting
Education
Recreation
Miscellaneous
Total
Expenditu Calculation
re
of degrees
50
(50/100)
*360
15
10
5
Degrees
10
5
5
100
36
18
18
180
54
36
18
Expenditure
Food
Clothing
Housing
Fuel and Lighting
Education
Recreation
Miscellaneous
Three Dimensional Diagrams
•
•
•
•
Volume diagrams
Cubes ,cylinders and spheres
Advantage- To display data with wide magnitude
Pictograms-Easy to understand
attractive
a pictorial symbol is used to indicate the item
facts presented are remembered for a long
time
cannot show the actual data properly
Cartograms
• Maps used to present statistical data on a
geographical basis
• Example-rate of literacy in different parts of
India