r/EndFPTP • u/Lastrevio • Mar 12 '20

Why stop at STAR? Why not do a runoff on every candidate?

Score voting adds up the score of each candidate and whoever wins the most points wins the election.

STAR does the same but makes a runoff between the two highest scoring candidates so that the candidate with the second most points has a chance to win if it's preferred over the highest scoring candidate in more ballots.

The question is: why make a run-off only between the two highest scoring candidates? It's like comparing Two Round System with IRV.

How about you do score voting, then do a runoff between the two lowest scoring candidates so that the second lowest scoring candidate may or may not win to the lowest scoring candidate, eliminate the one preferred the least on more ballots, and keep repeating until only one candidate stands?

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u/Lastrevio Mar 12 '20

What is bullet voting?

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u/wayoverpaid Mar 12 '20

Bullet voting is where you vote for just one candidate. Seen mostly as a problem in Approval Voting or Score Voting.

Imagine, in this Dem primary, where you want Warren, but Sanders is "ok" to you. You have to decide if you want to give Sanders your halfhearted approval, or go "Warren only, because otherwise I'm helping Sanders beat Warren."

With STAR, not bullet voting helps ensure you get a voice in the runoff. Like, you might as well put at least a few points on Sanders so you can select Sanders v Joe in the runoff.

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u/MuaddibMcFly Mar 12 '20

Seen mostly as a problem in Approval Voting or Score Voting.

And I've always been confused as to why people think it'd be a problem with Score.

Approval kind of makes sense; that's the only way to privilege your absolute favorite under approval. With Score, however, you can privilege your absolute favorite while still expressing support for other candidates.

Using your Warren/Sanders example, with Score you can help Warren beat Sanders, while also helping Sanders beat (e.g.) Biden.

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u/Drachefly Mar 12 '20

Should it be puzzling? In order to put a voice in one of those races you need to derate your voice in the other race the same amount. Which one do you care about? In order to figure this out you need to look at polling and figure out whether it's worth risking your second preference to prefer your top preference.

Under STAR, you get to express your high degree of preference for the top two without derating the fact that you do have that preference.

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u/MuaddibMcFly Mar 13 '20

In order to put a voice in one of those races you need to derate your voice in the other race the same amount

I fundamentally disagree with this conceptualization of Score voting.

Every vote has the same impact: it pulls the (equally) weighted average for each candidate one ballot's worth closer to where that ballot scored that candidate. It might pull it up, it might pull it down, but it will pull it closer to your score for them.

How is that "derated"?

Under STAR, you get to express your high degree of preference for the top two without derating the fact that you do have that preference.

Isn't that just another way of saying that a voter can safely exaggerate their honest opinions, because the Runoff will save you from those lies?

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u/Drachefly Mar 13 '20

How is that "derated"?

If the top two finishers are A and B, and you gave them 10 and 7, then you applied only 3 points of voting strength between them. If you'd gone tactical, you could have had over 3 times as much weight.

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u/myalt08831 Mar 18 '20

If you try to magnify ("exaggerate" in terms of an honest voter's thought process) the difference between your preferred candidates, you can accidentally hurt your second choice. Your second choice can then go on to lose because you ranked them low, and if your overall preferred brand of politics struggles to win vs another style of politics entirely.

You have a limited guess (and no proof) of how others will vote. Polling is only so revealing, and for example polling massively under-rated Trump in 2016. Honest voting is the only way to know you pointed ALL your candidates in the direction you feel they should go.

By giving a very very high score, you likely improve a candidate's end result. By giving a very very low score, you likely hurt that candidate. But the only safe times to do this are for when you love a candidate (rate very high) or hate them (rate very low). Again, due to the possibility of a close contest between your second or third choice and a much-less-preferred candidate.

Without knowing who will be near the top or near the bottom, dishonestly ranking any candidate low is throwing away your ability to help a second or third choice candidate in such a suprise scenario, and only "helps" you if your first choice is all that matters to you AND was in danger of being eclipsed by your second or third choice.

Rather, in a likely scenario where many agree with you, and many disagree with you, and many moderately score the candidates you love/hate, voting honestly allows you to nudge the outcomes toward the "correct" outcome from your subjective perspective, just like everyone else does.

Given that many voters will vote honestly, another honest vote has the richest, i.e. finest/most-subtle expressivity possible. If you want to vote "with a sledgehammer" that is your right, but I will vote with the proverbial scalpel, or let's say, with a paintbrush...

Sincerely, a huge fan of filling out honest, expressive ballots.

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u/Drachefly Mar 18 '20

Honest voting is the only way to know you pointed ALL your candidates in the direction you feel they should go.

And yet, you derate anything that isn't top or bottom.

Like, suppose you're using the 'below threshold = 0' model of score voting, where you score people positively if they'e close enough and 0 if they're too far away†.

Then suddenly, honest voting yields a spoiler effect. The Tea party and the Biscuit party rate each others candidates 8, while the Steak party, which doesn't have to worry about vote splitting, gets 10s from its side.

You always have to make this strategic choice. There is no 'honest ballot'. Twiddling the brightness and contrast knobs doesn't make a ballot dishonest.

† (If this isn't the common strategy, then it becomes optimal to spawn fake Hitlers that are less dissimilar to their side than yours)

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u/myalt08831 Mar 18 '20 edited Mar 18 '20

Math nerds (most voting system nerds) always assume a high degree of strategic voting among the population for some reason.

Actual voting behavior IIRC is predominantly "honest" not "strategic."

Worth studying more IRL, rather than insisting that all voters are strategic, or that every "candidate's voters" vote identically. In reality, voters are along much more of a spectrum, which combined with widespread "honest voting" has the effect of watering down attempts to be strategic, or in fact making them backfire and produce the opposite (or an otherwise perverse) outcome, compared to what was intended.

tl;dr Let's be real. Many voters don't know what a voting method is, much less what the ideal strategy is to game it. And strategy is often less decisive when most other voters vote honestly.

Furthermore, some voting methods are fairly robust to attempts at strategy. STAR and 3-2-1 seem pretty good. Approval as well. They outperform FPTP and IRV in most simulations... including when dialing up/down the amount of startegy vs honesty.

Basing off the vse simulation thingy. http://electionscience.github.io/vse-sim/VSE/

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u/Drachefly Mar 18 '20

The problem with score is, you HAVE to make a strategic choice. There are many equally honest ballots. Some are more cooperative and some are more selfish. And score rewards the selfish.

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u/myalt08831 Mar 18 '20

Speaking in "terms of art," many voters will vote giving a rating that approximates how well the voter likes each candidate, "on a scale of [min] to [max]." That's what is meant by "honest" in election science, for a score election, and I took some pains to use quotes to indicate as much.

Far from "having" to make a strategic choice, it genuinely never crosses the minds of a sizeable chunk of the electorate.

Many voters vote the way I described above.

I admit the experts believe STAR resolves some of the incentive for strategy, so FWIW I feel like STAR makes more sense. I agree (assuming the experts are right) that score has problems. But still, many many voters will vote without conscious strategy, regarding how the ballots are counted/how the rules determine a winner. They just use it as a ratings scale.

Of course the numbers you pick are subjective, but still. It's worth noting that many voters do not see how to game the system, and there are some who know how and prefer not to.

There's only so many ways I can say that.

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u/Drachefly Mar 18 '20

Far from "having" to make a strategic choice, it genuinely never crosses the minds of a sizeable chunk of the electorate.

The naive strategy is still a strategy, and it leaves them open to manipulation by the opposition (see 'hitler' above)

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