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.
Zagorath@aussie.zone 8 months ago
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 describe them.