Talk:Instant-runoff voting: Difference between revisions
→Fixing the shortcomings of IRV
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: http://www.votefair.org/clone_iia_success_rates.png
: --[[User:VoteFair|VoteFair]] ([[User talk:VoteFair|talk]]) 22:54, 5 December 2023 (UTC)
Regarding IIA, I think IRV can fail less.
Here’s a very strong example of IIA failing in IRV. I got this from somewhere on Wikipedia.
6 C > B > D > A
5 D > A > C > B
5 A > C > B > D
4 B > D > A > C
One-choice elects C. IRV elects C, Borda (4-3-2-1) elects C, Copeland elects C. I would elect A in step 8 or step 9.
Taking D out:
6 C > B > A
10 A > C > B
4 B > A > C
One-choice elects A, IRV elects A, Borda (3-2-1) elects A, Copeland elects A. I would elect A in step 5 or step 6.
In looking for the above example, I came across this one from the University of Nebraska where One-choice, Borda and IRV fail.
<nowiki>https://mathbooks.unl.edu/Contemporary/sec-5-5-arrow.html</nowiki>
6 A>B>D>C
5 D>B>C>A
4 C>D>B>A
2 B>C>D>A
IRV elects C. I will elect D in step 8
Taking B out:
6 A>D>C
5 D>C>A
4 C>D>A
2 C>D>A
IRV elects C. I will elect D in step 8.
Food for thought. [[User:RalphInOttawa|RalphInOttawa]] ([[User talk:RalphInOttawa|talk]]) 01:44, 8 December 2023 (UTC)
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