When I was working on a cruise ship, a noticeboard poster said it all: “Please remember that Americans consider it acceptable to brag about their kids. Australians do not.”
Instant runoff voting is preferential. Preferential is a property that a voting system can have, where you number candidates in order of preference.
Instant runoff is one specific algorithm that can be used which is preferential. Single transferable vote, used in the Senate, is another preferential system. It’s also sort of a general case of IRV, allowing for more than one winner per race. (Or it might be more accurate to say that IRV is a special case of STV where N=1.)
Another preferential system is Minimax. Minimax basically simulates every possible head-to-head race between two of the candidates and declares the overall winner to be the one who performed best* across all of those races. I don’t actually think it’s used anywhere in the real world.
But incidentally, if you do hear the term “preferential voting” used, they’re probably talking about IRV. It’s the most common and the simplest preferential system.
* is does this by asking “which candidate performed the best in their worst match-up?”
It is not preferential. At the and of the day just one member is elected, sometimes with only 50.1% approval from the voters. The preferences of the other 49.9% are ignored. The Senate is preferential because a cohort of voters is electing multiple members. The votes are tallied and handed out by preferences. Say there are five seats. Labor gets 60% and Liberals get 40%, so it’s 3 seats for Labor and 2 for the Liberals. Everyone’s preferences were considered.
The non-electorate seats in NZ work the same way, using a national tally to hand out those seats by preference.
Instant-runoff is just a way of having a bunch of first past the post elections in one go. “If this candidate was eliminated, who would you vote for? Okay, but if that candidate was eliminated, who would you vote for?”. That’s how non-instant runoff elections work too. Until eventually you’re left with two people standing and one has more overall support.
Edit: As well if someone gets more than 50% first preferences they just win outright. Just because we use the word preference to describe that doesn’t make it preferential voting. It needs to represent the vote of all people.
Are you considering preferential with proportional? Preferential means you order your preferences. No more, no less. A proportional system (of which STV is a quasi-member, being somewhat proportional, but not quite as purely proportional as most other proportional systems) is one where people’s overall wishes are better taken into account, and the resulting parliament is a better representation of the will of voters.
Instant-runoff is just a way of having a bunch of first past the post elections in one go
Eh, sort of. It’s a way of doing a runoff voting system all in one go. It’s like the system parliamentary parties use to choose their leader, where they do one vote, eliminate the last place candidate, and then do another vote, and repeat. It’s not really FPTP because the highest-scoring candidate in each round isn’t what’s relevant, the lowest-scoring is.
But I think we both understand how the elections work from a mechanical standpoint. You’re just not clear on the correct terminology to refer to them.
Only the Senate is preferential. The lower house uses Instant-runoff Voting.
Instant runoff voting is preferential. Preferential is a property that a voting system can have, where you number candidates in order of preference.
Instant runoff is one specific algorithm that can be used which is preferential. Single transferable vote, used in the Senate, is another preferential system. It’s also sort of a general case of IRV, allowing for more than one winner per race. (Or it might be more accurate to say that IRV is a special case of STV where N=1.)
Another preferential system is Minimax. Minimax basically simulates every possible head-to-head race between two of the candidates and declares the overall winner to be the one who performed best* across all of those races. I don’t actually think it’s used anywhere in the real world.
But incidentally, if you do hear the term “preferential voting” used, they’re probably talking about IRV. It’s the most common and the simplest preferential system.
* is does this by asking “which candidate performed the best in their worst match-up?”
It is not preferential. At the and of the day just one member is elected, sometimes with only 50.1% approval from the voters. The preferences of the other 49.9% are ignored. The Senate is preferential because a cohort of voters is electing multiple members. The votes are tallied and handed out by preferences. Say there are five seats. Labor gets 60% and Liberals get 40%, so it’s 3 seats for Labor and 2 for the Liberals. Everyone’s preferences were considered.
The non-electorate seats in NZ work the same way, using a national tally to hand out those seats by preference.
Instant-runoff is just a way of having a bunch of first past the post elections in one go. “If this candidate was eliminated, who would you vote for? Okay, but if that candidate was eliminated, who would you vote for?”. That’s how non-instant runoff elections work too. Until eventually you’re left with two people standing and one has more overall support.
Edit: As well if someone gets more than 50% first preferences they just win outright. Just because we use the word preference to describe that doesn’t make it preferential voting. It needs to represent the vote of all people.
Are you considering preferential with proportional? Preferential means you order your preferences. No more, no less. A proportional system (of which STV is a quasi-member, being somewhat proportional, but not quite as purely proportional as most other proportional systems) is one where people’s overall wishes are better taken into account, and the resulting parliament is a better representation of the will of voters.
Eh, sort of. It’s a way of doing a runoff voting system all in one go. It’s like the system parliamentary parties use to choose their leader, where they do one vote, eliminate the last place candidate, and then do another vote, and repeat. It’s not really FPTP because the highest-scoring candidate in each round isn’t what’s relevant, the lowest-scoring is.
But I think we both understand how the elections work from a mechanical standpoint. You’re just not clear on the correct terminology to refer to them.