1. Welcome to Week 01 Thurs MAT135 Statistics

2. Math Club is a great place for CCD students to gather to play with puzzles and meet their peers. Math Club will have the first meeting on Tuesday 24 January 2017 at 3:30pm in CHR 126. Any questions, please contact or

3. Where’s Our Stuff???
Please go to my web page: vf-tropi.com

4. Questions?

5. Organizing Data
The population is huge We can’t handle it So we take a sample We take counts or measurements on the sample These are messy and hard to understand NOW WHAT???

6. Organizing Data
Step 1: Put your data into Excel Step 2: Graph it!

7. Organizing Data Open Excel Enter the data:
This is called a “Data Table”

8. Organizing Data
Once in Excel we have a variety of organizing tools we can use for our data

9. Organizing Data
Always do a quick graph of your data table to identify problems

10. Graphs
The best way to understand any data set is to GRAPH IT!

11. Graphs
If you don’t graph your data, the Stat Demons will get ya!

12. Graphs
Graphs are easier for most people to understand than a table of numbers or text

13. Graphs
Graphs are pictures of something mathematical - counts - measurements - a mathematical relationship

14. Graphs=Charts=Plots=Diagrams

15. Excel Graphs
Graphs are easy-peasy in Excel!

16. Excel Graphs
Highlight the data in your data table Be sure to include your labels!

17. Excel Graphs
Click the “Insert” tab In the middle is “Charts” Pick the chart you want!

18. Excel Graphs
TAH-DAH! A (kinda ugly) graph!

19. Excel Graphs
But… you aren’t done yet! (You were hoping… right?)

20. Excel Graphs
Graphs need to be a complete story in themselves By looking at the graph, the viewer should understand the question and its answer

21. Excel Graphs Graphs need: Titles Axis labels Legends
If you don’t have these…
you get points taken off!

22. Excel Graphs
The perfect beautiful and informative graph!

23. Questions?

24. History of Graphs
In the 14th century Nicole Oresme used a bar chart to plot the velocity of a constantly accelerating object vs time

25. History of Graphs
Each bar is of equal width, and this is one of the fundamental rules of bar graphs to this very day

26. History of Graphs
In the early 1600s René Descartes invented the x-y “scatter” plot

27. History of Graphs
In 1765 Joseph Priestley created a timeline which was a horizontal bar graph

28. History of Graphs
In 1780, William Playfair used bar charts to show Scottish imports/exports

29. History of Graphs
This is the first example of numerical data being split into categories and plotted as bars This is the reason Playfair is credited with the invention of the bar chart

30. History of Graphs
A fancy pie chart by William Playfair 1801

31. History of Graphs
A close-up of one of the pies:

32. History of Graphs
In the early 1800s, Adolphe Quetelet pioneered graphing things over time – the “time series graph”

33. Influential Graphs
John Snow’s dot plot map of the London cholera epidemic

34. Influential Graphs
Florence Nightingale’s “rose”

35. Florence Nightingale and the ASA

36. Influential Graphs
Minard’s flow map

37. Influential Graphs
Mann, Bradley and Hughes Hockey Stick graph

38. Questions?

39. What About the Other Types of Graphs?

40. Types of Graphs
Bar and column charts should be used to highlight differences in the actual number Pie charts are super for highlighting percentages

41. Types of Graphs Here’s some salary data for the Chicago Bulls in 1998:
Player
Salary
Michael Jordan
$33,140,000
Ron Harper
$4,560,000
Toni Kukoc
Dennis Rodman
$4,500,000
Luc Longley
$3,184,900
Scottie Pippen
$2,775,000
Bill Wennington
$1,800,000

42. TYPES OF GRAPHS
IN-CLASS PROBLEM 4
How can we show that Michael Jordan is paid a lot more than everyone else on the team?
Player
Salary
Michael Jordan
$33,140,000
Ron Harper
$4,560,000
Toni Kukoc
Dennis Rodman
$4,500,000
Luc Longley
$3,184,900
Scottie Pippen
$2,775,000
Bill Wennington
$1,800,000

43. Types of Graphs Graphs!!! Player Salary Michael Jordan $33,140,000
Ron Harper
$4,560,000
Toni Kukoc
Dennis Rodman
$4,500,000
Luc Longley
$3,184,900
Scottie Pippen
$2,775,000
Bill Wennington
$1,800,000

44. What does the bar chart tell you?
TYPES OF GRAPHS
IN-CLASS PROBLEM 5
What does the bar chart tell you?

45. What does the pie chart tell you?
TYPES OF GRAPHS
IN-CLASS PROBLEM 6
What does the pie chart tell you?

46. Types of Graphs
Pareto plot An ordered bar chart

47. Types of Graphs
Bars that are not based on counts can be positive or negative

48. Types of Graphs
We used bar/column graphs to display measurement data (salaries, profit/loss, etc.) There are other ways to show measurement data also

49. Types of Graphs
Scatter plot aka: x-y plot requires paired data you don't split the data into classes or categories

50. Types of Graphs
Scatter plot

51. Time series plot the x-axis variable is "time"
Types of Graphs
Time series plot the x-axis variable is "time"

52. Types of Graphs
More exotic types of graphs

53. Open/Hi/Low/Close plot
Types of Graphs
Open/Hi/Low/Close plot

54. Types of Graphs
Bubble chart

55. Types of Graphs
Map graph

56. Rule of Thumb:
Use column, bar and pie charts for categorical count data Use line, scatter and area charts for quantitative measurement data

57. Questions?

58. Graphs
Graphs have a psychological component that CANNOT be ignored

59. How to Lie with Statistics #2
How to lie with graphs

60. Lying with graphs
Where’s the zero?

64. What is the “lying’ in the original Terri Schiavo poll graph?
HOW TO LIE WITH GRAPHS
IN-CLASS PROBLEM 7
What is the “lying’ in the original Terri Schiavo poll graph?

65. Tricks our eyes play on us...
Lying with graphs
Tricks our eyes play on us...

66. Unintentional Optical Art?

67. What is the problem with the Cotton Textiles graph?
HOW TO LIE WITH GRAPHS
IN-CLASS PROBLEM 8
What is the problem with the Cotton Textiles graph?

68. Just because technology lets you make a 3D graph doesn’t necessarily
HOW TO LIE WITH GRAPHS
IN-CLASS PROBLEM 9
Just because technology lets you make a 3D
graph doesn’t
necessarily
mean it’s a
good idea…

69. The “Too Pretty to Live” graph

70. Sometimes pretty is just lying…

72. How the real graph should look:

73. What is the problem with the Fuel Economy Standards for Autos graph?
HOW TO LIE WITH GRAPHS
IN-CLASS PROBLEM 10
What is the problem with the Fuel Economy Standards for Autos graph?

74. Agenda Graphs with an The way a graph is drawn can have some
powerful psychological
impacts misleading
viewers
Data from National
Association of Realtors

75. HOW TO LIE WITH GRAPHS
IN-CLASS PROBLEM 11
Which graph (top or bottom) would show a strong, growing housing market?

76. HOW TO LIE WITH GRAPHS
IN-CLASS PROBLEM 12
Which would show the cost of a new house is not going up as much as people think?

77. Graphs made of things that look like real objects are especially dangerous – our minds think “area” or “volume” and not “width” or “height” alone

78. The second image is supposed to show that 1940s steel capacity is 1
The second image is supposed to show that 1940s steel capacity is 1.45 times that of the 1930s
Our minds
think "area" for
two-dimensional
figures
We see this
as 1.45 x 1.45
or 2.10 times bigger
From: How to Lie with Statistics by Darrell Huff

79. How it should look: The area of the second pic is now 1.45 times the
first

80. It’s even worse with things that look three dimensional
In 1860, there were 8 million cows in the U.S. vs. 25 million in 1936 (3.125 times more)
Our minds are thinking
“volume”:
3.125 x x 3.125 =
times bigger!
From: How to Lie with Statistics by Darrell Huff

81. How it should look:

82. Obviously lying:

83. How it should look:

84. What is the problem with using 2D or 3D pictographs?
HOW TO LIE WITH GRAPHS
IN-CLASS PROBLEM 13
What is the problem with using 2D or 3D pictographs?

85. Self-Fulfilling Prophecies

86. Self-Fulfilling Prophecies

87. How to Lie with Videos
Video

88. Questions?

89. You survived!
Don’t forget your homework due next week! Have a great rest of the week!