2004 Presidential Election

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2004 Presidential Election

• The following two slides show each candidates
  predicted percentage of votes from the polls
  taken two weeks before the election.

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Who do you think won?

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Candidate 1 Candidate 2
5

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How was the data misrepresented?

• By the Scale that was chosen
• By the Interval that was chosen

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More Examples.

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More Examples

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10

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Ways to misrepresent data

• By the Scale that is chosen
• By the Interval that is chosen
• Not starting at 0
• No title
• No labels

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Can you find what is wrong with these next graphs?

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These graphs represent the increase in cellular
phone use from 1990 to 2000.

Which graph makes it look like there was a
greater increase in cell phone use?
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These graphs represent the number of cars sold by
a particular dealership from 1995 to 1999.

Which graph makes it look like there was little
decrease in sales?
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Other ways to misrepresent data..

• In a company, there are 10 employees that make
  10,000 a year. The boss makes 80,000 a year.
  A job recruiter tells interested applicants that
  the typical salary for the company is 16,363 a
  year.

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• What measure (mean, median, or mode) did the job
  recruiter use?
• Mean
• What measure should the job recruiter have used?
• Median

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When do we use Mean, Median, or Mode?

• Meanwhen the data values are close together.
• Medianwhen there are extreme values.
• Be sure there are no big gaps in the middle of
  the data.
• Modewhen there are many identical numbers.

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Ways to Misrepresent Data

• By the Scale that is chosen
• By the Interval that is chosen
• Not starting at 0
• No title
• No labels
• Using an inappropriate measure of center (mean,
  median, or mode).

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Sources

• http//www.glencoe.com/sec/math/prealg/prealg03/ex
  tra_examples/chapter12/lesson12_5.pdf
• http//images.google.com/imgres?imgurlhttp//www.
  ced.appstate.edu/goodmanj/workshops/ABS04/graphs/
  chevrolet.jpgimgrefurlhttp//www.ced.appstate.ed
  u/goodmanj/workshops/ABS04/graphs/graphs.htmlh6
  40w479sz99tbnidr1-8gyPpdXUJtbnh135tbnw1
  01hlenstart7prev/images3Fq3Dmisleading2Bg
  raphs26svnum3D1026hl3Den26lr3D26rls3DGGLD,
  GGLD2005-16,GGLDen26sa3DN
• Cnn.com

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