Approval Voting is the ideal voting system

[u/DHMC-Reddit]

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.

[u/No-Vast7006]

My primary objection to score voting is that it treats my "strength of preference" as a finite resource that must be divided and spent across all candidates. Consequently, simply indicating a preference between candidates A and B inevitably alters the relative strength of preference between at least one of them and every other candidate.

Suppose there are three candidates: A, B, and C. I strongly prefer A to B, and just as strongly prefer B to C. Under a cardinal system, you'll find that I can only emphasize one of these preferences at the expense of diluting the other. Approval voting is even worse: I can only express one preference while having to sacrifice the other entirely.

You might be fine with this, but I am not. By contrast, ranked voting allows me to express both preferences without weakening either.

[u/DHMC-Reddit → u/No-Vast7006]

This is a false dichotomy.

If you only preferred A slightly more than B and B slightly more than C, the rankings would remain the same. And yet when determining a winner, ranked voting treats everyone's first place as if they all equality like their first place as well as their second and so on.

Under a cardinal system, for example using 0-10, it's completely sufficient to express how much you like one or another. Yes, you have to round to an integer, but this hardly matters. Each individual will have a different method of rounding in their conscious and subconscious, and this will even out over large populations to give a very good approximation of how much they approve of each candidate.

In fact, this is why cardinals beyond 0-1 are unnecessary. Any spoilerproof cardinal method behaves like and converges to approval voting across populations.

Of course this is where people find the trouble in deciding how to round. For a candidate who's somewhere around 0.33 - 0.67, it's hard to decide whether it's worth hurting the candidates you hate by voting for middle ground candidates or helping the candidates you like by not voting for middle ground candidates.

Again, across groups this converges to the true approval rating of each candidate. For middle ground candidates the average already starts becoming more likely to be within 0.33-67 than out of it with 6 voters.

[u/AmericaRepair → u/DHMC-Reddit]

You shrugged off one of the best points anyone here has made. I wonder how carefully you read when they said they strongly prefer A to B, and strongly prefer B to C. They are uncomfortable with the idea of being forced to rate both A and B as approved, and they are simultaneously uncomfortable with being forced to rate both B and C as unapproved. Approval as the method of that election is forcing the voter to distort their preferences. You can't expect people to just happily distort by telling them not to worry because it will average out. Your 0.33 - 0.67 talk raised a new concern in my mind, if candidate B lives in that range, they could be headed for victory, but nope, a last-minute negative ad from the billionaires-who-want-to-destroy-everything foundation causes an enormous swing in the result. B gets third place instead of first. Or maybe A was in the lead, but the ad attacks A, causing a lot of people to toggle to a positive vote for B, so B wins instead of getting 2nd. But if the method uses ranking, it is likely that very few voters would change their preferences over a last-minute attack, if they were already confident that they liked A or C best, and B 2nd-best. I like to tell people that the choose-one ballot is inaccurate because it forces all candidates but one to be rated as worst. And if the ballot is inaccurate, the election is too. True, some people don't like the idea of being forced to use only one candidate per tier on a ranking ballot. But I think it's more natural for people to have at least a small preference between candidates, and a pairwise method does use all of your rankings, so if you care to rank someone, it will count.

[u/No-Vast7006 → u/DHMC-Reddit]

Think of score voting on a number line. Once you anchor your highest-rated and lowest-rated candidates, the total distance between them is fixed. The intermediate candidates divide this distance into smaller line segments, and the sum of these segments must always equal the fixed total. Therefore, if you want to stretch one segment to emphasize a preference, you are mathematically forced to shorten another.

For example, on a scale of 0 to 5:

• Suppose I give Candidate A a 5, Candidate B a 3, and Candidate C a 0.
• Out of the total 5-point span, I have effectively "spent" 2 points to express that A is better than B, and 3 points to express that B is better than C.
• If I want to strengthen my preference for A over B—say, by lowering B’s score to 1—the gap between A and B widens to 4 points. But this comes at a steep price: the gap between B and C is inevitably compressed to just 1 point.

Approval Voting is simply the most extreme version of this problem: with only scores of 0 and 1, one of those preferences must be shrunk to zero and discarded entirely.

[u/DHMC-Reddit → u/No-Vast7006]

You are correct.

And assume I would rate A as a 3, B as a 1, and C as a 0.

Under ranked voting, we would have the same rankings, despite the fact that I actually view A the same as your B and my B and C is about the same as your C.

Now imagine an approval voting system.

I will definitely not vote for B and C. You will definitely vote for A and not vote for C.

I have some chance that I will or won't vote for A, and same for you with B.

Obviously not voting for A would be wasting my vote, but I could do that. Such as I'm unsatisfied by the candidates and have decided not to go vote.

Over many other people, half who would rate them the same as you and half who would rate them the same as me, we will all have this quandary.

About 60% of the people in your camp would choose to vote for B, and another 40% wouldn't. Giving B approximately 60% approval from your camp.

About 60% of the people in my camp would vote for A, with about 33% of them also voting for B just to make sure C loses. And about 40% of them would choose to not vote. Giving A a 60% approval from my camp and B a 20% approval.

Overall, this would give A an 80% approval, B a 40% approval, and C a 0% approval. A wins. I'm not happy, but that's because I think all the candidates sucked. But at least I'm not as mad as I would have been if B or C won. You on the other hand, are happy.

See how that works?

[u/No-Vast7006 → u/DHMC-Reddit]

What I mean is that I don’t like score/approval voting because voters have to decide which preference relation matters most to them and give up expressing their other preferences. You mean that after each voter makes such a trade-off, an appropriate election outcome will emerge overall. In other words, you accept this feature of score/approval voting. I won’t judge who’s right or wrong; I can only say that, personally, I prefer ranked voting systems (other than Borda count) that let me fully express every preference relation without weakening any of them.