Post on 24-Jun-2020
Day 20: How to (Not) Lie with Statistics
Daniel J. Mallinson
School of Public AffairsPenn State Harrisburgmallinson@psu.edu
PUBPL 304
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Road map
Discuss how to identify a misleading use of data
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Opening Question
Have you encountered examples of misleadingpresentations of data? How did you know?
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Know Your Sample (Huff Ch. 1)
Issues Raised in Chapter 1
Sampling frame
Importance of respresentative sample
Non-response bias
Self-reported data
Unknowing “rigging”
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Famous Example - Alf Landon wins!
1936 Literary Digest Poll
Figure: “Alf Landon,” public domainFigure: “FDR” by FDR Presidential Library,
CC BY 2.0
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Famous Example1936 Literary Digest Poll
Figure: “1936 Electoral College” by AndyHogan14, public domain
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Misleading Comparisons
BP Oil Spill
“The Gulf of Mexico is a very big ocean. The amount of volume ofoil and dispersant we are putting into it is tiny in relation to the totalwater volume.” (Tony Hayward, BP CEO)
Ground Water Removal by Bottled Water Companies
http://www.lulu.com/items/volume_62/957000/957317/9/
print/957317.pdf
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Misleading Figures (Duff Ch. 5)
How to spot a misleading graph
https:
//www.youtube.com/watch?v=E91bGT9BjYk&feature=youtu.be
Labels
Numbers
Scale
Context
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Misleading FiguresWatch Those Axes!
Figure: Blitz, Shelby 2017Mallinson Day 20 October 06, 2017 9 / 17
Misleading FiguresWatch Those Axes!
Figure: Bump, Philip 2015
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Misleading FiguresWatch Those Axes!
Figure: Bump, Philip 2015
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Misleading FiguresWatch Those Axes!
Figure: Bump, Philip 2015
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Misleading FiguresWatch Those Axes!
Figure: Bump, Philip 2015
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Misleading Figures
Correlation vs. Causation
Figure: “Spurious Correlations” by Tyler Viglen licensed under CC BY 4.0
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Bad InfographicsWhat is the problem here?
Figure: Knopfler, Jack 2015
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Bad InfographicsWhat is the problem here?
Figure: Knopfler, Jack 2015
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Homework
Complete the provided homework sheet. Due Monday
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