Selected topics in finite mathematics/Condorcet criterion

[Give a very very brief overview of the criteria?]

ObjectivesEdit

To satisfy the Condorcet criterion, a candidate that is favored to beat ever other candidate in a pairwise race wins. Therefore, if a candidate can defeat every other candidate, then they should win.

DetailsEdit

[State the definition of the criteria?]

[Rephrase the criteria into if-then form?]

[Give a prose-explanation of the criteria?]

ExamplesEdit

The Condorcet method satisfies the Condorcet criteria. Indeed, this is its namesake: if a candidate wins all pairwise races, that candidate wins by the Condorcet method.

Sequential pariwise elections also satisfies the Condorcet criterion. In particular, suppose A wins in all pairwise races. Then as soon as A comes up in the agenda, A will win every [pairwise] race until declared the winner.

NonexamplesEdit

Plurality fails to satisfy the Condorcet criterion. Consider the following election. A wins in all pairwise elections, but instead B wins by plurality.

1st choice A B C
2nd choice B A A
3rd choice C C B
Number of votes 2 3 2

Borda count fails to satisfy the Condorcet criterion. Consider the following election. One on one A wins all pairwise races. However, in this election as it is, B wins.

1st choice B E D
2nd choice C A A
3rd choice F B B
4th choice A C E
5th choice E D C
6th choice D F F
Number of votes 1 1 1

Sequential runoffs fail to satisfy the Condorcet Criterion. Consider the following election. Indeed one on one A could defeat either candidate. But in the election as a whole, A is eliminated first.

1st choice A B C
2nd choice B A A
3rd choice C C B
Number of votes 2 3 3

FAQEdit

HomeworkEdit

[Create two elections: one which satisfies the criteria and one which does not?]