[EM] Real IRV Ranked Ballots

Eric Gorr eric at ericgorr.net
Tue Mar 2 13:57:30 PST 2004


Through my efforts to get out there an advocate for both Approval and 
good Condorcet Methods (MAM, etc.), I am currently in communication 
with a dedicated IRV supporter who may be claiming that they would 
move away from IRV if a real example could be given where IRV 
selected an obviously wrong winner.

Naturally, I will be testing my movie survey results against IRV.

In the meantime, they have stated:

>I believe Ireland and Australia report full ranked
>ballots.

Can anyone verify this or submit any proof that it is not true?


Also, wanted to thank Adam Tarr for providing the following two examples:

10% FarRight>Right>Centrist>Left>FarLeft
10% Right>FarRight>Centrist>Left>FarLeft
15% Right>Centrist>FarRight>Left>FarLeft
16% Centrist>Right>Left>FarRight>FarLeft
15% Centrist>Left>Right>FarLeft>FarRight
13% Left>Centrist>FarLeft>Right>FarRight
11% Left>FarLeft>Centrist>Right>FarRight
10% FarLeft>Left>Centrist>Right>FarRight

7%  FarRight>Right>LuckyRight>ModerateRight>ModerateLeft
2%  Right>FarRight>LuckyRight>ModerateRight>ModerateLeft
4%  Right>LuckyRight>FarRight>ModerateRight>ModerateLeft
7%  LuckyRight>ModerateRight>Right>ModerateLeft
15% ModerateRight>LuckyRight>ModerateLeft>Right
16% ModerateLeft>ModerateRight>LuckyRight>Left
15% ModerateLeft>Left>ModerateRight>FarLeft>LuckyRight
13% Left>ModerateLeft>FarLeft
11% Left>FarLeft>ModerateLeft
10% FarLeft>Left>ModerateLeft

which I have been using extensively to provide IRV supporters 
evidence that IRV can fail rather dramatically in realistic cases. 
For the moment, none have been able to mount a defense for why IRV 
selects the winner it does. The current IRV supporter rejected the 
examples outright, calling the voters 'oddly split' and rejecting 
that examples such as these would ever occur.

If anyone has more realistic examples where IRV selects an extremely 
poor winner, I would be interested.





More information about the Election-Methods mailing list