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The resource is link is a very weak critique of IRV. consider their criticism of Aus 2007 general election. https://rangevoting.org/Aus07.html https://rangevot

The resource is link is a very weak critique of IRV. consider their criticism of Aus 2007 general election. https://rangevoting.org/Aus07.html https://rangevoting.org/Aus07.html The key point which is laboured a couple of times is that some seat results are different than plurality outcomes. But that is a feature of IRV, not a bug. Had the election been run under plurality rules voters would of voted differently and this fact seems to of escaped the author of this website. Voters who preferenced greens first, recognising a minor parties zero chance of winning under plurality would of instead cast votes according to two party preferred lineup, who mostly would ideologically align with labour. But under IRV they can vote for anyone they feel more closely represents them but still have meaningful input into a 2PP outcome. Show me a critique of an IRV outcome where 2PP outcome violates Monotonicity and you'll have a real critique of IRV.

caf 8y ago
Agreed. The lived experience in Australia (which has now used "IRV" in national elections for 100 years) is that in almost every case, the IRV winner was also the likely Condorcet winner (which certainly can not be said of first-past-the-post in practice). However, in close three-cornered races, tactical voting does sometimes come into play. The recent Wentworth by-election was an example of this: Liberal voters could have assisted their party to win the election by switching their first preference to the Labor candidate, because if the Labor candidate had beaten the eventual winner (Phelps, Independent) into second place, then Phelps' preferences would have been distributed and almost certainly given the win to the Liberal. Of course, this is a risky strategy, because if too many Liberal voters did this then they would have instead engineered a Labor win. And in reality, despite the possibility of tactical voting, the Condorcet winner Phelps won anyway. An example where the Condorcet winner may not have won is the seat of Rockhampton in the 2017 Queensland State election. The primary votes had Labor in first, independent Margaret Strelow in second, One Nation in third and the LNP in fourth. However preferences from the LNP candidate pushed One Nation into second, which gave Labor the win on Strelow's preferences. It seems likely that Strelow would have beaten any of the other three head-to-head, though. And as previously mentioned, this sort of situation is notable for its rarity.
- dragonsngoblins 8y ago
  Tactical voting is only a concern if people don't fully preference, which I always do (and encourage others to do). Surely if you can be bothered to vote "tactically" you can be bothered to fully preference
  - caf 8y ago
    The given example (Wentworth) was a House of Reps by-election, in which full preferences are required for a vote to be formal anyway. That doesn't affect the tactical voting possibility there - the possibility arose because the Liberal candidate's chances were greatly affected by which of the other two major contenders made it into the final runoff.

caf 8y ago

Agreed. The lived experience in Australia (which has now used "IRV" in national elections for 100 years) is that in almost every case, the IRV winner was also the likely Condorcet winner (which certainly can not be said of first-past-the-post in practice). However, in close three-cornered races, tactical voting does sometimes come into play. The recent Wentworth by-election was an example of this: Liberal voters could have assisted their party to win the election by switching their first preference to the Labor candidate, because if the Labor candidate had beaten the eventual winner (Phelps, Independent) into second place, then Phelps' preferences would have been distributed and almost certainly given the win to the Liberal. Of course, this is a risky strategy, because if too many Liberal voters did this then they would have instead engineered a Labor win. And in reality, despite the possibility of tactical voting, the Condorcet winner Phelps won anyway. An example where the Condorcet winner may not have won is the seat of Rockhampton in the 2017 Queensland State election. The primary votes had Labor in first, independent Margaret Strelow in second, One Nation in third and the LNP in fourth. However preferences from the LNP candidate pushed One Nation into second, which gave Labor the win on Strelow's preferences. It seems likely that Strelow would have beaten any of the other three head-to-head, though. And as previously mentioned, this sort of situation is notable for its rarity.

dragonsngoblins 8y ago
Tactical voting is only a concern if people don't fully preference, which I always do (and encourage others to do). Surely if you can be bothered to vote "tactically" you can be bothered to fully preference
- caf 8y ago
  The given example (Wentworth) was a House of Reps by-election, in which full preferences are required for a vote to be formal anyway. That doesn't affect the tactical voting possibility there - the possibility arose because the Liberal candidate's chances were greatly affected by which of the other two major contenders made it into the final runoff.