Talk:Mixed ballot transferable vote

Merge with MSV?

@Rankedchoicevoter This article seems to me like it's talking about dual vote systems (separate party and candidate votes), though I'm not 100% sure I read it correctly. If that's the case, do you think we should group it together with the mixed single vote article, so we can discuss the distinction between single and double-vote systems in one place? Closed Limelike Curves (talk) 18:51, 10 August 2024 (UTC)

It's currently about a specific version of dual vote systems. I saw your change in the electoral system that reflected this and modified it a bit (at least temporarily having the classic dual vote version redirect to MMP).

Problem is we now have multiple pages dedicated to two-vote mixed systems. There's this one (mixed ballot) which is probably the most different so that's fine. But we also have AMS which focuses on dual vote AMS/MMP in the UK, and I guess Korea a bit as well as failed versions from before. Theres MMP focusing on two vote MMP in general. Then there is scorporo which is again a different two vote system, and even though the Hungarian one was never called scorporo (that's Italian) it is in there too.

Whereas there only one page for mixed single vote, which contains both one vote MMP and the single vote PVT system. Which is fine, I think we don't want a proliferation of single vote pages, let's keep it as it is. But the problem is MSV says its also called PVT, while scorporo says NVT. The problem is sources are very scares, different, and a bit unclear on this. PVT, NVT, even DVT.

I'd say lets keep MSV mostly as is, but make it clear that its more just a ballot form. It may be used for more classic MMP (seat linkage) as well as vote linkage (PVT/NVT(??)/even DVT)

Let's put a page on dual vote on hold until the MMP/AMS is figured out, I'll add some more sources to MBTV though. It's very similar to MPP systems proposed by Schulz and Quinn, and if we treat it as a ballot type, then there's plenty here for it's own page, distinct from MSV and classic dual vote MMP/scorporo.

We keep the scorporo article as a page on a specific system that was in Italy, without the need to also have it as a page on NVT. Bit like the AV+ article exists separate from AMS, but better since scorporo was actually implemented, is more unique and noteworthy for the history.

And finally, we create a page like "mixed vote transfer system", "vote transfer mixed system", or "vote linkage mixed system". This article will be an overview on all vote linkage systems, including scorporo, the two Hungarian systems in use now, the old Hungarian system, the old German system it was based on and also on the non compensatory DVT, which I guess is like parallel voting but without ticket splitting (Italy again could be the main point, what we can check where else it exists). It will have the different sources views and definitions of PVT, NVT, how it relates to AMS/MMP, how it relates to STV. It should have examples differentiating the seat linkage compensation and the vote linkage compensation. I'll start collecting sources and generating the diagrams for the comparison. Rankedchoicevoter (talk) 10:21, 11 August 2024 (UTC)

I looked for other sources on MBTV but couldn't find any outside of the Bachelor's thesis you cited, which I don't think satisfies WP:RS.

I'm still a bit confused on vote vs. seat linkage. Would vote linkage just mean this kind of mechanism:

1. Elect winners in local races,
2. Take any wasted votes (votes for losing candidates+votes in excess of Droop quota for the winner) and assign them to the nationwide party, then use those to apportion party list seats.

If so, the second system sounds like it produces roughly, but not exactly, the same results, but only after a living hell of elaborate calculations for the vote flows that will produce numbers that don't quite add up the way you'd logically expect them to. This would also explain my confusion: I think divisor methods will give the same results for vote and seat linkage, thanks to the coherence property. In that case, it could be handled as part of a discussion on apportionment. Closed Limelike Curves (talk) 02:47, 24 August 2024 (UTC)

It's possible that the term isn't used elsewhere, but the problem is these are so niche systems that basically even when there is good literature on them, it might no be in English or when it is they use very different terminology. I am now trying to write a coherent "vote linkage mixed system" article. I will put as as many sources as I can in it and then work my way through related articles.

https://en.wikipedia.org/wiki/Draft:Vote_linkage_mixed_system

I am working on the example that shows the difference to seat linkage

On your question on vote vs seat linkage that's exactly the problem, that in the versions actually implemented it's not the droop quota (so 50% in SMDs), but the votes of second place candidate. And sometimes nothing from winners. Now the thesis at least goes into this, but it's not the only one, I would search for more sources. I also has the good table for categorization, although there is another one I saw somewhere that I like better now. I'll work around it, don't want to give undue significance to lesser sources, but that's hard in this area, especially in English.

I recommend taking a glance at this:

https://www.tandfonline.com/doi/abs/10.1080/09644000412331307494

In the other three Länder located in the British Zone, a different mixed system was used.11 No universally accepted label has been attached to it.

Following Scammon,12 we will call it the ‘Losers and Surplus Method’ (LSM) for the purposes of this article. Superficially, this formula bore

striking resemblance to PPR as it combined first-past-the-post with PR, each voter casting a single vote. Most members were elected by firstpast-

the-post in either single- or multi-member constituencies, while the other members were elected by PR on the basis of a so-called ‘reserve

list’. The crucial difference with PPR was that, for the distribution of the PR seats, the d’Hondt formula was applied not to all votes cast, but to

amended vote totals including only

this is an old one, since then many other source say "vote transfer" or vote linkage so I'll go with that. And it's more broad, includes the no surplus ones too. (also, PPR means MMP here)

As for what to do with this article. I have learned more since I was editing this and would pivot it from this particular system, to any system with a vote-linkage dual vote setup, even the ones that ultimately use seat linkage too, like that Schulze one. And there's another from Jameson Quinn called "modified Bavarian MMP". The point is there should be a page for these ones, since they are no ordinary two-vote MMP, very different for tactical nominations. What it's name should be we could decide, I prefer something along the lines of "mixed ballot". Since the point is it's a single ballot with a mixed use, it's not a mixed single vote, it's dual in some sense, but in one. Mixed preferential voting could also work. Rankedchoicevoter (talk) 12:58, 25 August 2024 (UTC)

Ahh, OK I think I understand now. So the practical difference isn't that vote linkage and seat linkage produce very different results, but rather that countries using vote linkage generally only do partial vote linkage/transfer? e.g. only transferring the runner up's votes in Italy to encourage a two-party system? – Closed Limelike Curves (talk) 23:43, 28 August 2024 (UTC)

If the names are and the system is very niche, I would lean toward merging into another page that's better-sourced. – Closed Limelike Curves (talk) 23:45, 28 August 2024 (UTC)

I'll work on this page a little bit today to make it more clear, and will publish the vote linkage systems article. I think there's enough here to warrant an article but it should be about the mechanism, not a particular system that was never used. I'll let you know if its more or less done and sourced and then let me know whether you think there's too little here for it's own article. With the danger of interpreting all these sources verging onto original research, I think these mechanisms should be explained and I wish I could do a better job at it.

"So the practical difference isn't that vote linkage and seat linkage produce very different results, but rather that countries using vote linkage generally only do partial vote linkage/transfer? e.g. only transferring the runner up's votes in Italy to encourage a two-party system?"

No, unfortunately not. I don't know how to explain this easily, maybe take a look at the vote linkage article draft and let me know if it's understandable or if you'd rephrase. But let me try here:

So the typical system has fixed number of seats right? adding extra seats like in New Zealand and formerly Germany is the exception. So for both systems we use 50 FPP seats and 50 list seats and no tactical voting, in fact lets say there's only one vote (MSV).

Unless there are overhang seats, seat linkage (MMP) is proportional. But it would be proportional with more than 50 list seats too, and maybe below 50 too. And if there is overhang, it will by default not give any list seats to the parties with overhang, they are already overrepresented (maybe this is different in regionalized versions). But otherwise, no matter what number of list seats you set in advance, it will use it to get as proportional to list votes as it can.

Vote linkage is different. You have a fixed number of list seats again (I think if you could make it flexible, you could make it almost as proportional as seat linkage, but that has not been done in practice), and that determines the relative value of votes on the two tiers. Usually there's less than 50% of list seats, but more than 50% of votes get transferred (because of FPP and other parameters). So the effective value of transferred votes is lower than the votes for FPP winners. So you transfer some votes and you allocate the seats not in a top-up (seat linkage) way to the totality of list votes, but, you allocate seats like parallel voting, but not on all votes, just some of them. So that's why it's partially compensatory, not because on the runner-up gets transferred (you got that oen confused with something else). While non-winners are always slightly advantaged on the list tier, it does not do them that much good as under seat linkage, since the value of votes is almost always lower there.

Also, consider this: Under seat linkage if some party has overhang seats they are not entitled to more seats under a default fixed seat system. Under vote linkage that's not the case, even in the sort where no winner surplus votes are used. So there are 70 FPP seats and 30 list seats, and a party wins 40 FPP seats with 30% of the vote. They have overhang. But the 30% of the vote comes from all districts, not just where they won, since they didn't get 70/70 FPP they surely also got some votes in the other 30 districts. Those votes are definitely getting transferred, so they will get a few extra list seats even tough they are already overrepresented. Thats also they case when there are no overhang seats, sometimes parties just get too many list seats, there's no seat linkage rule to stop them at their proportional share, its a separate process. There's only vote linkage which tells you what votes to work with, but no seat linkage which tells you watch out, that party already won some FPTP seats, take that into account. And this is both a strength and a weakness depending on the setup. Seat linkage can be gamed by pretending your FPP winners aren't with your list (decoy list), while vote linkage cannot always be gamed like that (though sometimes yes, in Italy they didn't do it well), but there might be other strategies, and also it puts more significance on FPP since it doesn't completely compensate for it.

Did I explain it well? Rankedchoicevoter (talk) 08:15, 29 August 2024 (UTC)

I think I'm starting to understand now with that last example, although I'm not 100% sure.

So, let me check if I'm getting this right:

• We have two sets of seats, direct and party-list
• List seats are apportioned proportionally (?) to the number of wasted votes
• The number of list seats is fixed instead of varying in proportion to the number of wasted votes (?), which means the list seat mechanism can undercompensate or even severely overcompensate, if the proportion is not set correctly.

Let me know if I'm understanding this correctly, because I'm not sure if this system is stupid or if I'm being stupid :p – Closed Limelike Curves (talk) 19:52, 30 August 2024 (UTC)

Yes, exactly. And the proportion is in practice never set correctly, mainly because it depends on the election results, and secondly because they always made it that the list votes count less (erring on the side of less compensation instead of overcompensation).

With seat linkage, you never have overcompensation as far as I know. Rankedchoicevoter (talk) 09:57, 31 August 2024 (UTC)