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Can you solve the fantasy election riddle? - Dennis E. Shasha

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TEDEd Animation

Let’s Begin…

After much debate, the realm has decided dragon jousting may not be the best way to choose its leaders, and has begun transitioning to democracy. Your company was hired to survey the citizens of the land and predict which candidate will win. There’s a lot riding on this: if you get it wrong, heads— well, your head— will quite literally roll. Can you predict the winner? Dennis Shasha shows how.

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Suppose there are two candidates A and B. You poll 300 people with the following rule: each person P flips a fair coin twice. If the coin comes up heads both times, then P should vote for A. If the coin comes up tails both times, then P should vote for B. Otherwise P should vote for the candidate P prefers. If 20% of the people like A and 80% like B, approximately what poll score will B receive?

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Meet The Creators

  • Educator Dennis E. Shasha
  • Director Igor Coric, Artrake Studio
  • Narrator Addison Anderson
  • Director of Production Gerta Xhelo
  • Editorial Director Alex Rosenthal
  • Producer Bethany Cutmore-Scott
  • Script Editor Alex Gendler
  • Fact-Checker Eden Girma

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