Fiasco in 1936 Survey Brought Science To Election Polling

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Fiasco in 1936 Survey Brought Science To
Election Polling

• Cynthia Crossen
• The Wall Street Journal
• October 2,2006. pg B1

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President Alf Landon?

• In 1936, Literary Digest magazine, predicted that
  Alf Landon, governor of Kansas, would win in a
  landslide over Franklin Roosevelt.
• Literary Digests poll sent out 10 million survey
  ballots that year.
• Literary Digest had predicted 5 previous
  presidential elections successfully.
• There was concern that the poll might create a
  bandwagon effect, giving Mr. Landon an even
  bigger victory.

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Results of the 1936 Election

• The Literary Digests poll was inaccurate.
• Mr. Roosevelt won the election with more than 60
  of the popular vote and took 46 out of 48 states.
• Mr. Landon only won the states of Maine and
  Vermont.

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What Caused This Error?

• Systematic Error
• Survey ballots were only mailed to its
  subscribers which failed to represent the
  majority of the American population.
• Subscribers were mainly wealthy, republican
  Americans that owned cars and telephones at the
  time.

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Systematic Error

• Systematic error - Results from some imperfect
  aspect of the research design or from a mistake
  in the execution of the research.

• George Gallup, A market researcher and syndicated
  columnist at the time began experimenting with
  scientific methods of polling.
• He predicted that the Literary Digest survey poll
  for the 1936 election would be inaccurate.

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The 1948 election

• George Gallup predicted Thomas Dewey would beat
  Harry Truman in the election.
• He was so sure of his improved scientific methods
  of surveying, that he stopped collecting more
  polling data after October and predicted Dewey
  would win.
• However, Gallups fallacy was that people still
  had a month to decide who to vote for.
• The result was that Harry Truman won the election.