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Condorcet Method

We continue with the same table:

Preference Schedule

  group of 18 group of 12 group of 10 group of 9 group of 4 group of 2
Killians 512424
Molson 155555
Samuel Adams234133
Guinness 441242
Meister Brau323311

The Condorcet method is the final method for computing the winner. First, for each pair of candidates determine which candidate is preferred by the most voters. For example, here is a comparison between Samuel Adams and Guinness (the number of supporters in the first row represents the number of voters who prefer Samuel Adams to Guinness, and vice-versa for the second row):

  # of supporters
Samuel Adams 43 (18 + 12 + 9 + 4)
Guinness 12 (10 + 2)

Winner for this pair is Samuel Adams

If there is a candidate who 'wins' EVERY comparison with all other candidates, then this candidate is the winner. If there is no such candidate, then there is no Condorcet winner.

Note: you can define a "winning" candidate as that candidate having a number of preferential votes which is greater than or equal to the number of preferential votes of all other candidates when the candidates are compared pairwise. There isn't always a Condorcet winner. If no candidate satisfies this condition for winning, then there is no Condorcet winner.

Practice
Condorcet Method

Using the Condorcet method, which beer would win under the above preference schedule? Do not forget to press "Enter".

Click here if you need an explanation for the example above.


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