1. Business Statistics, 4e by Ken Black
Chapter 2
Charts
& Graphs
Business Statistics, 4e, by Ken Black. © 2003 John Wiley & Sons.

2. Learning Objectives
Recognize the difference between grouped and ungrouped data
Construct a frequency distribution
Construct a histogram, a frequency polygon, an ogive, a pie chart, a stem and leaf plot, a Pareto chart, and a scatter plot
Business Statistics, 4e, by Ken Black. © 2003 John Wiley & Sons. 2

3. Ungrouped Versus Grouped Data
Ungrouped data
have not been summarized in any way
are also called raw data
Grouped data
have been organized into a frequency distribution
Business Statistics, 4e, by Ken Black. © 2003 John Wiley & Sons. 7

4. Example of Ungrouped Data42 30 53 50 52 55 49 61 74 26 58 40 28 36 33 31 37 32 23 43 29 34 47 35 64 46 57 25 60 54
Ages of a Sample of
Managers from
Urban Child Care
Centers in the
United States
Business Statistics, 4e, by Ken Black. © 2003 John Wiley & Sons. 8

5. Frequency Distribution of Child Care Manager’s Ages
Class Interval Frequency
20-under 30 6
30-under 40 18
40-under 50 11
50-under 60 11
60-under 70 3
70-under 80 1
Business Statistics, 4e, by Ken Black. © 2003 John Wiley & Sons. 9

6. Data Range Smallest Largest 42 30 53 50 52 55 49 61 74 26 58 40 28 3633 31 37 32 23 43 29 34 47 35 64 46 57 25 60 54
Smallest
Largest
Business Statistics, 4e, by Ken Black. © 2003 John Wiley & Sons. 10

7. Number of Classes and Class Width
The number of classes should be between 5 and 15.
Fewer than 5 classes cause excessive summarization.
More than 15 classes leave too much detail.
Class Width
Divide the range by the number of classes for an approximate class width
Round up to a convenient number
Business Statistics, 4e, by Ken Black. © 2003 John Wiley & Sons. 11

8. Class Midpoint
Business Statistics, 4e, by Ken Black. © 2003 John Wiley & Sons. 12

9. Relative Frequency Relative Class Interval Frequency Frequency
20-under
30-under
40-under
50-under
60-under
70-under
Total
Business Statistics, 4e, by Ken Black. © 2003 John Wiley & Sons. 13

10. Cumulative Frequency Cumulative Class Interval Frequency Frequency
20-under
30-under
40-under
50-under
60-under
70-under
Total 50
Business Statistics, 4e, by Ken Black. © 2003 John Wiley & Sons. 14

11. Class Midpoints, Relative Frequencies, and Cumulative Frequencies
Relative Cumulative
Class Interval Frequency Midpoint Frequency Frequency
20-under
30-under
40-under
50-under
60-under
70-under
Total
Business Statistics, 4e, by Ken Black. © 2003 John Wiley & Sons. 15

12. Cumulative Relative Frequencies
Relative Cumulative Relative
Class Interval Frequency Frequency Frequency Frequency
20-under
30-under
40-under
50-under
60-under
70-under
Total
Business Statistics, 4e, by Ken Black. © 2003 John Wiley & Sons. 16

13. Common Statistical Graphs
Histogram -- vertical bar chart of frequencies
Frequency Polygon -- line graph of frequencies
Ogive -- line graph of cumulative frequencies
Pie Chart -- proportional representation for categories of a whole
Stem and Leaf Plot
Pareto Chart
Scatter Plot
Business Statistics, 4e, by Ken Black. © 2003 John Wiley & Sons. 17

14. Histogram Class Interval Frequency 20-under 30 6 30-under 40 18
Business Statistics, 4e, by Ken Black. © 2003 John Wiley & Sons. 18

15. Histogram Construction
Class Interval Frequency
20-under 30 6
30-under 40 18
40-under 50 11
50-under 60 11
60-under 70 3
70-under 80 1
Business Statistics, 4e, by Ken Black. © 2003 John Wiley & Sons. 19

16. Frequency Polygon Class Interval Frequency 20-under 30 6
Business Statistics, 4e, by Ken Black. © 2003 John Wiley & Sons. 20

17. Ogive Cumulative Class Interval Frequency 20-under 30 6 30-under 40 24
Business Statistics, 4e, by Ken Black. © 2003 John Wiley & Sons. 21

18. Relative Frequency Ogive
Cumulative
Relative
Class Interval Frequency
20-under
30-under
40-under
50-under
60-under
70-under
Business Statistics, 4e, by Ken Black. © 2003 John Wiley & Sons. 22

19. Complaints by Amtrak Passengers
NUMBER
PROPORTION
DEGREES
Stations, etc.
28,000
.40
144.0
Train
Performance
14,700
.21
75.6
Equipment
10,500
.15
50.4
Personnel
9,800
.14
50.6
Schedules,
etc.
7,000
.10
36.0
Total
70,000
1.00
360.0
Business Statistics, 4e, by Ken Black. © 2003 John Wiley & Sons.

20. Complaints by Amtrak Passengers
Business Statistics, 4e, by Ken Black. © 2003 John Wiley & Sons.

21. Second Quarter Truck Production in the U.S. (Hypothetical values)
Company A B C D E
Totals
357,411
354,936
160,997
34,099
12,747
920,190
Business Statistics, 4e, by Ken Black. © 2003 John Wiley & Sons. 25

22. Second Quarter U.S. Truck Production
Business Statistics, 4e, by Ken Black. © 2003 John Wiley & Sons. 26

23. Pie Chart Calculations for Company A
2d Quarter
Truck
Production
Proportion
Degrees
Company A B C D E
Totals
357,411
354,936
160,997
34,099
12,747
920,190
.388
.386
.175
.037
.014
1.000
140
139 63 13 5
360
Business Statistics, 4e, by Ken Black. © 2003 John Wiley & Sons. 27

24. Safety Examination Scores for Plant Trainees
Raw Data
Stem
Leaf 2 3 4 5 6 7 8 9 3 9
7 9
5 6 9 86 76 23 77 81 79 68 92 59 75 83 49 91 47 72 82 74 70 56 60 88 97 39 78 94 55 67 89
Business Statistics, 4e, by Ken Black. © 2003 John Wiley & Sons. 28

25. Construction of Stem and Leaf Plot
Raw Data
Stem
Leaf 2 3 4 5 6 7 8 9 3 9
7 9
5 6 9 86 76 23 77 81 79 68 92 59 75 83 49 91 47 72 82 74 70 56 60 88 97 39 78 94 55 67 89
Stem
Leaf
Stem
Leaf
Business Statistics, 4e, by Ken Black. © 2003 John Wiley & Sons. 29

26. Pareto Chart Frequency 10 20 30 40 50 60 70 80 90 100 Poor Wiring10 20 30 40 50 60 70 80 90
100
Poor
Wiring
Short in
Coil
Defective
Plug
Other
Frequency 0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
Business Statistics, 4e, by Ken Black. © 2003 John Wiley & Sons.

27. Scatter Plot Registered Vehicles (1000's)
Gasoline Sales (1000's of Gallons) 5 60 15
120 9 90
140 7
Business Statistics, 4e, by Ken Black. © 2003 John Wiley & Sons.