Data Visualisation

1. Data Visualization
Dr. Amitabh Mishra 1
24%
18%
13%
18%
11%
7%
9%

2. Data Visualization or Presentation
• Data visualization means-
“to convey information through visual representations”
• Visalisation tools produces
“interactive visual representations of data to reinforce
human cognition; enabling the viewer to gain knowledge
about the internal structure of the data and causal
relationships in it”
Dr. Amitabh Mishra 2

3. Significance of Visualization/
Presentation
• They give a bird’s eye view of entire data
• They are attractive to the eye
• They have great memorizing effect
• They facilitate comparison
• They give visual indications of
– Magnitudes,
– Grouping,
– Trends and patterns
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4. Functions of Visualization/
Presentation
• Three functions of visualization are:
– Record
i.e. Store information
– Analyze
i.e. Support reasoning about information
– Communicate
i.e. Convey information to others
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5. Tools for Visualization
(Diagrammatic & Graphic Representation)
Visualization/
Representation
Diagrammatic
Representation
Bar-diagram
Pie-chart
Pictogram
Graphic
Representation
Histogram
Frequency Polygon
Smoothed Frequency
Curve
Cumulative Frequency
Curve (Ogive)
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6. Tools for Visualization
(Diagrammatic & Graphic Representation)
• Diagrammatic Representation
a) Bar-diagram (One dimensional diagram)
b) Pie-chart (Two dimensional diagram)
c) Pictogram/ Cartograms (Statistical Maps)
• Graphic Representation
a) Histogram
b) Frequency Polygon
c) Smoothed Frequency Curve
d) Cumulative Frequency Curve (Ogive)
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7. DIAGRAMMATIC REPRESENTATION
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-20%
0%
20%
40%
60%
80%
100%
1986 1987 1988
profit/loss
polishing
other cost
wages

8. Types of Diagram
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Diagrammatic
Representation
Bar-diagram
(One Dimensional Diagram)
Pie-chart
(Two Dimensional Diagram
Pictogram/Cartograms
(Statistical Maps)

9. BAR DIAGRAM
One Dimensional Diagram
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0
100
200
300
400
500
600
700
1993-94 1994-95 1995-95
Rs
lakhs
years

10. Bar Diagram
• “Bar-Diagram are vertical lines where length of the bars
are proportional to their corresponding numerical values”.
• “Bar is a thick line whose width is shown merely for
attention”.
– But, all bars should have the same width so as not to confuse
the reader of diagram.
• It is called one dimensional diagram because it is only
length of bar which matters not the width.
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11. • Width of bars should be uniform through out the
diagram
• The gap between one diagram and other should be
uniform
• Bars may be either
– Horizontal or
– Vertical
• The vertical bars should be preferred because they give a better look
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C4
1Q
4Q
3Q
2Q
1Q
1.5
1.2
0.9
0.6
0.3
0.0
Figure 1-11:SHIFTINGGEARS
2003 2004
Quartely netincome for General Motors (inbillions)

12. Types of Bar Diagram
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Bar Diagram
Simple bar diagram
Sub-divided Bar diagram
Multiple-bars diagram
Percentage-bar diagram
Deviation bars diagram

13. Types of Bar Diagram
1. Simple bar diagram
2. Sub-divided Bar diagram
3. Multiple-bars diagram
4. Percentage-bar diagram
5. Deviation bars.
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14. Simple Bar diagram
• It is used to represent only one variable
• Ex-
– Figures of sales for various years
– Figures of production for various years
– Figures of population for various years
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15. • Following table gives
birth rate per thousand
of different countries
over a period of time.
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0
5
10
15
20
25
30
35
40
45
india germany united
kingdom
china new zeland swedan
birth rate per thousand of different countries
Country Birth rate
India 33
Germany 16
U.K 20
China 40
Newzealand 30
Swedan 15

16. Example 2:
Fund flow for various years may be shown by means of
a simple bar-diagram
Year
Funds Flow
(Rs. crores)
2009-10 85.80
2010-11 109.61
2011-22 204.29
2012-13 126.31
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0
50
100
150
200
250
2009-10
2010-11
2011-12
2012-13
Funds Flow
Funds Flow

17. Exercise: 1
Prepare a Simple bar diagram for your internal and external marks in previous
semester examination
Subject
Name
External
Marks
Internal
Marks
Total
Marks
Marketing 67 30 97
Organizational
Behavior
55 25 80
Accounting 45 20 65
Computer
Application
60 28 88
Statistics 39 21 60
Production &
Operations
48 25 73
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0 10 20 30 40 50 60 70 80
Marketing
Organizational
Accounting
Computer Application
Statistics
Production & Operations
Marketing
Organizati
onal
Accounting
Computer
Application
Statistics
Production
&
Operations
External Marks 67 55 45 60 39 48
External Marks

18. Sub-divided Bar Diagram
• “In Sub divided Bar Diagram each bar representing
the magnitude of given phenomenon is further
subdivided in its various components”.
• Each component occupies a part of the bar
proportional to its share in total.
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19. • The growth of production of fish for
the period 1950-51 to 1986-87 is-
(In lakh tonnes).
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0
5
10
15
20
25
30
35
1950-51
1960-61
1970-71
1980-81
1984-85
1985-86
PRODUCTION
OF
FISH
YEARS
inland
marine
Year Marine Inland total
1950-51 5.34 2.18 7.52
1960-61 8.80 2.80 11.60
1970-71 10.86 6.70 17.56
1980-81 15.55 8.87 24.42
1984-85 16.98 11.03 28.01
1985-86 17.16 11.60 28.76
1986-87 12.47 8.42 20.89

20. Exercise
Prepare a sub-divided bar diagram for your internal and external marks in
previous semester examination
Subject
Name
External
Marks
Internal
Marks
Total
Marks
Marketing 67 30 97
Organizational
Behavior
55 25 80
Accounting 45 20 65
Computer
Application
60 28 88
Statistics 39 21 60
Production &
Operations
48 25 73
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Marketi
ng
Org
Beha
Accoun
ting
Comp
App
Statistic
s
Pro &
Oper
Internal 30 25 20 28 21 25
External 67 55 45 60 39 48
0
20
40
60
80
100
120
MArks
internal and external marks

21. Multiple-bars diagram
• In multiple bars “two or more set of
interrelated data are represented”.
• This diagram should be preferred, when ever
comparison between two or more related
variables is to be made.
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22. 0
20
40
60
80
100
120
140
160
1984 1985 1986 1987
sales
gross profit
net profit
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• Draw a suitable diagram
from the following data-
Year Sales Gross
profit
Net
profit
1984 120 40 20
1985 135 45 20
1986 140 55 35
1987 150 60 40

23. 2002-03 2003-04
Gross profits
Profits before tax
Profit after tax
Retained profits
3104
1663
1219
846
3123
1376
982
589
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3104 3123
1663
1376
1219
982
846
589
0
500
1000
1500
2000
2500
3000
3500
2002-03 2003-04
Gross Profits
Profits Before
Tax
Profit After
Tax
Retained
Profits

24. Percentage-bar diagram
• “Sub-divided bar chart drawn on percentage basis is
known as percentage bar diagram”.
• In Percentage bar diagram, we express each
component as the percentage of its respective total.
• Bars of length equal to 100 for each class are drawn at
first step and sub-divided in the proportion of the
percentage of their component in the second step.
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25. • Represent the following by sub divided bar diagram on percentage
basis-
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Particulars 1986 1987 1988
Cost/chair
Wages 9 15 21
Other costs 6 10 14
Polishing 3 5 7
Total 18 30 42
Proceeds
/chair
20 30 40
Profit/loss +2 - -2

26. Particulars 1986 1987 1988
Cost/chair
Wages 45 50 52.5
Other
costs
30 33.3 35
Polishing 15 16.7 17.5
Total cost 90 100 105
Sales price 100 100 100
Profit/loss +10 - -5.0
-20%
0%
20%
40%
60%
80%
100%
1986 1987 1988
profit/loss
polishing
other cost
wages
Dr. Amitabh Mishra 26
Take the sales price/chair as 100 and
express the other figures in
percentages. The percentages so
obtained are given below-

27. Items Expenses
%
Expense
s
Food
Clothing
House Rent
Education
5550
5100
4800
4950
27.21%
25%
23.53%
24.26%
Total 20400 100%
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27.21
25
24.26
23.53
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
%Expenses
education
house rent
clothing
food

28. Deviation Bar-diagram
• Deviation bars are popularly used for representing net quantity-
excess or deficit i.e.
– Net profit,
– Net loss,
– Net exports, or
– Net imports, etc.
• Such bars can have both positive and negative values. Positive
values are shown above the base line and negative values below it.
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29. Year Sales
Net
profits
2011-12
14%
29%
2012-13 11% 61%
2013-14
17% -21%
-30%
-20%
-10%
0%
10%
20%
30%
40%
50%
60%
70%
sales net profit
2001-02
2002-03
2003-04
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2001-02 2002-03 2003-04
sales 14% 11% 17%
net profit 29% 61% -21%

30. Two dimensional diagram
or
Surface Diagram/ Area Diagram
1. Pie diagrams.
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31. Pie Charts
or
Round
1st Qtr
2nd Qtr
3rd Qtr
4th Qtr
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32. • “A pie chart is a circular chart in which the circle
is divided into sectors. Each sector visually
represents an item in a data set to match the
amount of the item as a percentage or fraction of
the total data set”.
• Pie charts are useful to compare different parts of
a whole amount.
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33. • A pie chart is not useful for displaying relationships over
time or relationships among several variables.
• A pie chart should not require more than seven sections.
• The steps to draw a pie diagram are:
– Convert the various observations (in percent) in the data set
into corresponding degree in the circle by multiplying each by
3.6 (360 /100)
– Draw the circle and its parts using different degrees
33
Dr. Amitabh Mishra

34. Example
• Draw a pie chart for the following data of 6th
five year plan public sector outlays:
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Sector Percentage outlay
Agricultural and rural development 12.9%
Irrigation etc. 12.5%
Energy 27.2%
Industry and mineral 15.4%
Transport, communication etc. 15.9%
Social service and other 16.1%

35. The angle at the centre is given by-
=(Percentage outlay/100)x 360
= Percentage outlay x 3.6
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Sector Percentage
outlay
Angle at the centre
Agricultural and rural development 12.9% 12.9 x 3.6 = 46°
Irrigation etc. 12.5% 12.5 x 3.6 = 45°
Energy 27.2% 27.2 x 3.6 =98°
Industry and mineral 15.4% 15.4 x 3.6 = 56°
Transport, communication etc. 15.9% 15.9 x 3.6 = 57°
Social service and other 16.1% 16.1 x 3.6 = 58°
Total 100% 360°

36. Dr. Amitabh Mishra 36
13%
13%
15%
16%
16%
27%
Percentage outlay
Agricultural and rural
development
Industry and mineral
Transport,
communication etc.
Social service and other
Energy

37. U.S. Auto Sales 2003 - 2007
37
Dr. Amitabh Mishra

38. Pie Chart of 2007 U.S. Auto Sales
24%
18%
13%
18%
11%
7%
9%
GM
Ford
Chrysler
Toyota
Honda
Nissan
Other
38
Dr. Amitabh Mishra

39. 46%
27%
19%
5% 3%
Column2
Pacific
Atlantic
Indian
Antarctic
arctic
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Ocean Area % Area Degree
Pacific
Atlantic
Indian
Antarctic
arctic
70.8
41.2
28.5
7.6
4.8
46.31
26.94
18.64
4.96
3.15
166.70
97.00
67.10
17.89
11.31
Total 152.9 100.00 360.00

40. Pictographs
• “A pictograph uses small pictures or symbols to display
the data”.
• Pictographs do not depict results precisely. Hence, caution
should be exercised when using them.
• To construct pictograms the following suggestions are
made:
– The symbols must be simple and clear.
– The quantity represented by a symbol should be given.
40
Dr. Amitabh Mishra

41. Pictograph for 2007 U.S. Auto Sales
*Each Symbol Equals 1,000,000 Units
GM
Chrysler
Toyota
Honda
Nissan
Other
Ford
41
Dr. Amitabh Mishra

42. Dr. Amitabh Mishra 42
Example of pictogram:
Year Output
1999
2000
2001
2002
2004
2996
4052
5924
Output of cars during the year by a car
manufacturing company:
1999
2000
2001
2002
Scale = 1000 cars

43. Types of Graphs
graphs
Graphs of time
series or
Line graphs
Graph of
frequency
distribution
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44. Line graphs
or
graph of time series
• Graph of one variable.
• Graph of two or more variables.
• Graph having two scales.
• Range chart
• Band graph.
• Ratio chart.
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45. Graph of frequency distribution
• Histogram
• Frequency Polygon.
• Smoothed frequency curve.
• Ogives or cumulative frequency curves.
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46.  A histogram is a chart made of bars of different
heights.
Widths and locations of bars correspond to widths
and locations of data groupings
Heights of bars correspond to frequencies or
relative frequencies of data groupings
Histogram
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47. Frequency Histogram
Histogram Example
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Dr. Amitabh Mishra

48. Relative Frequency Histogram
Histogram Example
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Dr. Amitabh Mishra

49. Figure 23.6
Histogram of 2007 U.S. Auto Sales
0
500,000
1,000,000
1,500,000
2,000,000
2,500,000
3,000,000
3,500,000
4,000,000
4,500,000
GM
Ford
Chrysler
Toyota
Honda
Nissan
other
49
Dr. Amitabh Mishra

50.  Pie Charts
Categories represented as percentages of total
 Bar Graphs
Heights of rectangles represent group frequencies
 Frequency Polygons
Height of line represents frequency
 Ogives
Height of line represents cumulative frequency
 Time Plots
Represents values over time
1-8 Methods of Displaying Data
50
Dr. Amitabh Mishra

51. Pie Chart
33.0%
23.0%
19.0%
19.0%
6.0%
Category
Happy with career
Don't like my job but it is on my career path
Job is OK, but it is not on my career path
Enjoy job, but it is not on my career path
My job just pays the bills
Figure 1-10: Twentysomethings split on job satisfication
My job just pays the bills
Happy with career
Enjoy job, but it is not on my career path
Job OK, but it is not on my career path
Do not like my job, but it is on my career path
51
Dr. Amitabh Mishra

52. Relative Frequency Polygon Ogive
Frequency Polygon and Ogive
50
40
30
20
10
0
0.3
0.2
0.1
0.0
Sales
50
40
30
20
10
0
1.0
0.5
0.0
Sales
(Cumulative frequency or
relative frequency graph)
52
Dr. Amitabh Mishra

53. O
S
A
J
J
M
A
M
F
J
D
N
O
S
A
J
J
M
A
M
F
J
D
N
O
S
A
J
J
M
A
M
F
J
8.5
7.5
6.5
5.5
Month
M
i
l
l
i
o
n
s
o
f
T
o
n
s
Mo nthly S te e l P ro d uc tio n
Time Plot
53
Dr. Amitabh Mishra

54. Scatter Plots
• Scatter Plots are used to identify and report
any underlying relationships among pairs of
data sets.
• The plot consists of a scatter of points, each
point representing an observation.
54
Dr. Amitabh Mishra

55. Scatter Plots
• Scatter plot with
trend line.
• This type of
relationship is
known
as a positive
correlation.
Correlation will be
discussed in later
chapters.
55
Dr. Amitabh Mishra

56. U.S. Auto Sales 2003 - 2007
56
Dr. Amitabh Mishra

57. Guidelines for Graphs: Line Charts
• A line chart connects a series of data points using
continuous lines.
• This is an attractive way of illustrating trends and
changes over time.
• Several series can be compared on the same
chart, and forecasts, interpolations, and
extrapolations can be shown.
57
Dr. Amitabh Mishra

58. Line Chart of Total U.S. Auto Sales
Fig. 23.3
0
500000
1000000
1500000
2000000
2500000
3000000
3500000
4000000
4500000
5000000
2003 2004 2005 2006 2007
Unit
Sales
Year
GM
Ford
Chrysler
Toyota
Honda
Nissan
Other
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Dr. Amitabh Mishra

59. Guidelines for Graphs: Line Charts
• A stratum chart is a set of line charts in
which the data are successively
aggregated over the series.
• Areas between the line charts display the
magnitudes of the relevant variables.
59
Dr. Amitabh Mishra

60. Fig. 23.4
Stratum Chart of Total U.S. Auto Sales
0
2000000
4000000
6000000
8000000
10000000
12000000
14000000
16000000
18000000
20000000
2003 2004 2005 2006 2007
Unit
Sales
Year
Other
Nissan
Honda
Toyota
Chrysler
Ford
GM
60
Dr. Amitabh Mishra

61. Guidelines for Graphs:
Histograms and Bar Charts
• A bar chart displays data in various bars that
may be positioned horizontally or vertically.
• The histogram is a vertical bar chart in which
the height of the bars represents the relative
or cumulative frequency of occurrence of a
specific variable.
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Dr. Amitabh Mishra