IRV example where voting for somebody makes him lose

#voters their vote
9 A>B>C
6 B>A>C
5 C>B>A

In IRV, C has the least votes and hence is eliminated, and her votes transfer to B, so B wins over A. However, if two A>B>C voters had voted C>B>A (maximally dishonestly – completely reversing their preference order to lie as much as they could possibly lie), then:

#voters their vote
7 A>B>C
6 B>A>C
7 C>B>A

B has the least votes and is eliminated, giving her votes to A, and A wins. So voting against your preferred candidate here increases his chance of winning!

This example was posted on the net by somebody named "The Phantom." I liked it so I reposted it here.


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