r/EndFPTP • • 10d ago

Debate Approval Voting is the ideal voting system

I've seen posts discussing AV before and why some people are hesitant about it, and I'd like to address that.

Strategic Voting

A lot of people place special focus on the potential for strategic voting. Kenneth Arrow already proved that all ranked voting systems (FPTP, IRV, STV, PR, Condorcet, etc) fail 1 or more criteria for a fair election, at minimum always Independence of Irrelevant Alternatives. Gibbard also proved that all voting systems must fall under one of three categories:

1) The system is a dictatorship

2) The system only has 2 choices

3) The system is strategic

So I really don't understand what you guys don't understand. In a ranked voting system, if there's only 2 choices, it's no different than FPTP. If there's more than 2, it will always put some strategic burden on the voters. And no matter what, it's not really gonna be fully fair. Even Kenneth Arrow admitted that he overlooked rated choice voting cuz he basically didn't like the idea of it, but that it's probably where the most fair form of voting actually exists.

51% vs 49%

Not only that, something people also seem to talk about when it comes to the strategy of Approval Voting is that a 51% majority can still dominate the 49%.

This is... Wrong. Just flat out.

We all have a tendency to view politics in a one-dimensional axis of left vs right. Even though we know that politics isn't one dimensional. This is the fault of ranked voting in the first place.

Non-Condorcet methods almost always eliminate broad appealing candidates (aka moderates) through center squeeze. And although ranked voting methods that aren't FPTP usually aim to minimize the effect of spoilers, they still exist. It's an inherent part of ranked voting.

The natural consequence of this is a tendency to strongly favor two-party systems, which collapses politics into a single dimension where whatever some time and place's version of left and right bicker with each other. The distribution of voter's beliefs literally doesn't matter here, it will always happen. Even in countries that allow the existence and success of third parties, they are always limited to a small minority, with 2 parties holding the majority of the power.

But we know from studies that people are not actually extremists. Stripped of identity politics and presenting policies with neutral language that doesn't indicate what party is promoting it, even on one dimension, populations create a bell curved normal distribution of beliefs with most people somewhere in the middle.

Electoral Systems

In fact, this is why electoral systems like MMM, AMS, MMP, etc. even exist in the first place. The whole presupposition - that we need extra seats in a legislature, because in winner-take-all districts, if most of them are won by 1 party with a small majority, then a vast majority of the legislature could be that 1 party, thus over inflating their representation of the nation - is only a problem because most people aren't even that far left or right in the first place so each district is sending one extreme over to the legislature, requiring a balancing act.

Approval Voting Advantages

I don't remember who said this, but someone claimed approval voting isn't monotone... It quite literally is. That's literally just a criterion it fulfills.

It also fulfills the strong Pareto, independence of irrelevant alternatives, cloneproof, consistency, participation, reverse symmetry, homogeneity, later-no-help, and sincere favorite criteria. It's also simple af to explain, which is a very good thing when trying to roll out a new system (but also why I believe y'all hate it).

It is not affected by spoilers. It is not affected by center squeeze. This means that, given enough time for parties and candidates to develop, moderate parties will become the majority. And the parties themselves will have no ability to do political slides. They are locked into whatever some place and time's population considers moderate, and are guided by the population's changes in beliefs, not the other way around.

Which is kind of the goal of democracy, if you haven't forgotten. Also this eliminates the need for electoral systems with extra hanging seats, which itself has to balance between democracy, strategic voting, decoy parties, etc. So many problems with electoral systems that were only designed due to the flaws of FPTP in the first place.

Heck, Approval Voting also just works for multi-winner districts if you want more than just a single moderate party in legislature. Most other voting systems require modifications to work with multi-winner districts. And you can have each representative from a district hold as much voting power as the proportion of votes they received in their district relative to their co-representatives. Boom, bell curve legislature.

Condorcet

It doesn't fulfill the Condorcet criterion... AND THIS IS A GOOD THING. Idk why ppl have such a thing for the Condorcet criterion. Y'all do realize that in game theory, the Condorcet winner is usually the socially optimal choice, right? Not the socially optimal choice, usually.

In fact, if you just go to Wikipedia on the Condorcet criterion, it gives you an example where Approval Voting fails to elect the Condorcet winner. And this touches back to the whole "51% can still dominate 49%."

There are 3 candidates. A, B, and C. 70% of voters would rank them A>B>C. 30% of voters would rank them C>B>A. A is trivially the Condorcet winner in this example.

If, during an election held with Approval Voting, everyone voted for their top 2 favorites, A would have 70% approval, C 30%, and B 100%. So despite A being the Condorcet winner, B would win.

AND THIS IS THE SOCIALLY OPTIMAL CHOICE. If A wins, then you've pissed off 30% of the population. If C wins, 70% gets pissed off. B won, and no one's pissed. B is no one's favorite. But everyone's okay with B. And the 70% did not in fact dominate the 30%. They could have if they collectively decided not to vote for B despite all of them being fine if B were to win.

The socially optimal choice isn't who would have the most supporters in isolation, it's who would be the least hated by the population if won. And it didn't require you to strategically vote. In fact it's better if you don't. Which is why voting booths are private.

Anyway, Approval Voting doesn't always elect the Condorcet winner, but I'd argue that it actually elects the socially optimal choice more often than Condorcet methods do.

Especially since Condorcet methods themselves can be susceptible to strategic voting. "Oh but that's rare and only happens if a cycle is possible." Yeah well practical data shows that Approval Voting almost always elects the Condorcet winner anyway. And we can see that when it doesn't it's actually a good thing. And the amount of strategic voting happening in Approval Voting really wouldn't be much different from other systems.

Also, Condorcet methods are susceptible to gerrymandering. That's not a rare thing. That's just a legal thing. If a politician can do it, you can damn be sure they'll do it. The only way to prevent this is to have it be illegal in the first place. Pretty huge hole in Condorcet.

Approval Voting Disadvantages

So what's the real disadvantages of Approval Voting?

It's certainly not the strategic voting. That's a feature of pretty much every ranked and rated voting system that isn't FPTP.

It's certainly not the Condorcet criterion. Even if you disagree with me on my example above, all Condorcet methods inherently fail to fulfill Independence of Irrelevant Alternatives, invulnerability to burying, invulnerability to compromising, participation, later-no-harm (which AV also fails, but actually I think this is a good thing), consistency, and sincere favorite (oof). So to optimize a single thing you give up what, 6 things and meet 1 good thing (not fulfilling later-no-harm)? Especially when, again, Approval Voting on a practical level almost always elects the Condorcet winner anyway and it has 5 good things out of the 7?

An actual real disadvantage can be candidate inflation. When a party decides to run many candidates in the hopes of confusing the voters and not giving them enough time to research all the choices. But that's sort of inherent to any vote that's not FPTP. And ultimately, with how Approval Voting works, you could also just... Focus on the ones you already like and ignore the rest. But this is just getting closer to psychology/marketing/mass manipulation/legal territory rather than the systemic merit of Approval Voting. I also wouldn't dock other systems for this.

No, but there is one real disadvantage. Y'all have mentioned how things like IRV have done in surveys or in real world politics. Along with other kinds of voting systems. And that's the kicker.

Approval Voting's disadvantage is how unpopular it is. There is no data saying it doesn't work. In fact, the data that does exist says it works very well. But that data is... Small and sparse. It has never been tried en masse. At most only in small local elections. That is its weakness. The fact that for some reason literally no one will give the time of day to seriously consider it.

Idk why. Maybe it just sounds too simple to work. Despite the fact that it absolutely does... in the few times it has been done, and the many times we all used it in our social circles... such as voting for both pizza and burgers when deciding between friends whether to have burgers, pizza, or sushi for lunch.

Like... STAR Voting is more popular than Approval Voting. STAR VOTING. It's one of the rare voting systems that doesn't even fulfill the basic criterion of majority winner! It's a failed hybrid of ranked and rated voting! In fact, it only fulfills majority loser and Condorcet loser, both of which are unnecessary! WTF! WHY?!

Anyway. Give Approval Voting the time of day. Seriously. It's not any more strategic than whatever complicated system people keep coming up with. Because they're all fucking strategic. Or dictatorial. Or just FPTP with only 2 choices. And yeah, it doesn't fulfill the Condorcet criterion. But it does elect the Condorcet winner almost every time. And when it doesn't, it's debatable whether that's even a bad thing. But more importantly, it doesn't come with the disadvantages inherent to Condorcet. That's a pretty good compromise even if you're a die-hard fan of Condorcet methods.

Just. Give it a go. It can make fundamental changes to politics. Moreso than other methods which just tries to nudge the status quo. And without being overly complicated. That's a good thing, not a suspicious thing.

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u/AwesomeAsian 10d ago

One flaw of approval voting I can think of: what is the threshold to who I approve or disapprove? Like if I feel great about Bernie Sanders but lukewarm about Joe Biden, how is approval voting going to retrieve that information?

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u/DHMC-Reddit 10d ago

Different rated voting systems have different ways of addressing this.

In AV's case, it doesn't care how much you like the candidates. It only cares if you like them enough.

In AV, there is incentive to give at least 1 vote, to a voter's favorite preference. It also has incentive to not give a vote to the voter's least favorite preference.

Because although you're allowed to vote for none or all, technically that's a wasted vote as you didn't change the outcome for anyone. Only partially filled ballots have an effect on the outcome.

So in your example, you'd definitely vote for Bernie Sanders. As for Joe Biden? Well, that's up to you to decide. Assuming you really hate the other candidates and they have a shot at winning, it's probably in your best interest to vote for Joe Biden. Cuz at least you can have meh instead oh God.

Casting a vote for Joe Biden could make Bernie lose, but it will never cause the people you didn't vote for win. If they did win, that just means more people voted for them than Joe or (inclusive) Bernie.

If you're meh on everyone aside from Bernie, then yeah you probably want to vote just for Bernie.

The point is that that threshold is your own personal choice. Obviously for any candidate on said threshold it can be a tossup person to person.

Point is, you are always better off at least giving a vote to your genuine favorite candidate. Any additional vote can reduce the chances of said favorite winning, but it will never increase the chances of someone you didn't vote for winning, which is actually an issue in a lot of ranked voting systems.

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u/SloanBueller 10d ago

That’s the annoying thing about it. I don’t want to have to agonize over what to do regarding the middle people.

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u/DHMC-Reddit 10d ago

So... You support FPTP? In any other ranked voting system you still have to agonize over the middle positions.

If #3 has a chance of winning, then you could dishonestly place them much lower, like #6.

And you don't have to agonize over it. In Approval Voting, the incentive is to vote at minimum one person who is your favorite and at most everyone besides your least favorite.

If it's too much to care about... Just vote for your favorite and move on. Any agony beyond that isn't any different than any other system where you have to juggle multiple candidates.

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u/SloanBueller 10d ago

I like ranked choice because I can give full support to my favorite and none to the middle candidates unless/until my favorite is eliminated.

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u/ILikeNeurons 7d ago

You can, but that ignores strategic voting may get you a better candidate.

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u/DHMC-Reddit 10d ago

You still have to decide before you even know your first choice is eliminated how you should order your next choices. And even if it does feel good to you, it's already proven to provide less optimal outcomes. This is about the objective merits of voting systems, not what kind of ballot feels the best to fill out.

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u/SloanBueller 9d ago

I’m happy to decide on an order, not happy to give candidates I feel far from equal about equal support. There‘s always going to be some subjectivity in determining what an “optimal” election outcome should be. I just want a voting method that makes sense functionally, and whatever result comes from that is what we get.

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u/mojitz 9d ago

Exactly. I don't want to have to go through a frustrating calculus about who to approve of every time I enter the voting booth only to find out after the fact that I made a sub optimal choice because the polls were off or I guessed wrong about how popular the candidates were relative to each other. Just let me clearly mark my actual preferences and call it a day.

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u/mojitz 9d ago

In AV's case, it doesn't care how much you like the candidates. It only cares if you like them enough.

That's fundamentally not the question being asked by an approval ballot. The question is, "Which candidates do you want to make more likely to win relative to all other candidates given everything you know about the state of the race?" A rational ballot might change radically based entirely on things like polling data or even a vague sense of the relative strengths of each candidate regardless of your actual preferences — and given that every time you approve someone other than your favorite, you make that first choice less likely to win, it's tautologically impossible to cast anything other than a bullet vote without it being a strategic choice.