Lying with Statistics

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Where the Statistics Lie
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Where the Statistics Lie

• by
• James Guffey
• Professor of Mathematics
• Truman State University

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Quotes
There are three kinds of lies in the world
lies, damned lies, and statistics. -
Benjamin Disraeli
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Quotes
Many people use statistics like a drunk uses a
lamp post ...
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Quotes
Many people use statistics like a drunk uses a
lamp post ... more for support than for
illumination. - Andrew Lang
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Quotes
It aint so much the things we dont know that
get us in trouble. Its the things we know that
aint so. - Artemus Ward
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Some things to consider

• Is there any reason to suspect bias by the source
  of the results?
• How were the data collected?
• Are the data reasonable?
• Are the data useful and relevant?
• Are the graphs misleading?

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Choice Visa Card
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Choice Visa Card
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Choice Visa Card
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Smart Rate Discover Card
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Smart Rate Discover Card
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Smart Rate Discover Card
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How to Rig a Poll
I would be disappointed if Congress cut its
funding for public tv. Cuts would be...
Readers Digest, July 1995
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How to Rig a Poll
Cuts in funding for public tv are justified as
part of an overall effort to reduce federal
spending. Cuts would be...
Readers Digest, July 1995
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Assessing Poll Results

• Look for actual wording of the poll.
• Beware of false choices.
• Watch for selectively reported poll results.
• Look warily at polls that delve into technical
  matters.
• Be skeptical of polls commissioned by advocacy
  groups.

Readers Digest, July 1995
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Kirksville Daily Express, 2/8/2000
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Healthy Skepticism
Doubt is the beginning, not the end, of
wisdom. - Anonymous
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