Comment by Dylan16807
1 day ago
> Approval voting is the range compressed version of score voting.
I'm not thrilled with score voting to begin with, and compressing it down doesn't change much.
> Use score voting and you can give your favorite candidate a different score than your second favorite without giving them the same score as your least favorite.
That doesn't solve my problem. Take exactly what I said before, but replace "check" with "give the maximum score to".
> Both of them are still better than RCV.
I don't see how.
> I'm not thrilled with score voting to begin with, and compressing it down doesn't change much.
Compressing it makes it slightly worse, but some people think it makes it easier to understand. I tend to think that's silly; people can understand "score each candidate on a scale of 1 to 10" perfectly well. But approval voting would still be a significant improvement over FPTP, and even over RCV.
> That doesn't solve my problem. Take exactly what I said before, but replace "check" with "give the maximum score to".
RCV doesn't solve that either, because it's subject to Arrow's Impossibility Theorem. It's actually even worse, because it makes you give a lower rank (rather than an equal one) to your most favored candidate to prevent an even worse candidate from winning.
Suppose your favorite candidate is the first choice of 20% of the population, your second favorite is 25% and the two candidates you hate are at 25% and 30% respectively. RCV makes you give your top pick to the second candidate so they can beat one of the two candidates you hate and ensure the runoff isn't between both of the candidates you hate.
Meanwhile with score voting your favorite candidate might have won, because they were the first choice of only 20% but the second choice of everyone else, and then end up with an average score of e.g. 6 when all the others are at 4 and 5.
RCV tends to do the opposite of that. If you have two opposite extremists and a moderate, the moderate can get knocked out in the initial round and then you get a coin flip between the two opposite extremes, even if the moderate would win one-on-one against either of the extremes. Or, in a district that skews to one side, give the district to the other side, because the minority party makes it to the runoff with 40% of the vote, the majority party splits between two candidates each at ~30%, but then if the majority party's extremist goes to the runoff instead of its moderate, they could lose the runoff to the minority party's moderate and give the district to the minority party.
> Suppose your favorite candidate is the first choice of 20% of the population, your second favorite is 25% and the two candidates you hate are at 25% and 30% respectively. RCV makes you give your top pick to the second candidate so they can beat one of the two candidates you hate and ensure the runoff isn't between both of the candidates you hate.
Let's call those candidates A B X Y.
I don't see the issue. I vote my actual ranking, A is eliminated. If this scenario isn't super weirdly convoluted, more of those votes shift to B than X, so X is eliminated next. Now it's B versus Y. If I vote for B instead, the same thing happens and we also get B versus Y.
And what happens here in score voting could be basically anything. Not enough specifics.
> If you have two opposite extremists and a moderate, the moderate can get knocked out in the initial round and then you get a coin flip between the two opposite extremes, even if the moderate would win one-on-one against either of the extremes.
Yeah that's a real issue, and I'd want to use condorcet methods to fix that.
> Or, in a district that skews to one side, give the district to the other side, because the minority party makes it to the runoff with 40% of the vote, the majority party splits between two candidates each at ~30%, but then if the majority party's extremist goes to the runoff instead of its moderate, they could lose the runoff to the minority party's moderate and give the district to the minority party.
Meanwhile with approval or score voting, a lot of people pretend not to like the other party's moderate because they're trying to get their side to win and it gets really messy. Is there a need to have multiple candidates per party? If there is, a two stage election that picks party first and then picks probably-the-moderate is probably better than anything.
> If this scenario isn't super weirdly convoluted, more of those votes shift to B than X, so X is eliminated next.
It doesn't have to be that convoluted, all it takes is for the eliminated candidate to be a moderate so their votes go in two different directions. But you're right that I messed up that example; the percentages are wrong.
The problem case is when your second most favored candidate would otherwise be eliminated first and you need to prevent that by causing your most favored candidate to be eliminated instead, because the second best candidate has a better chance in the next round.
Suppose the candidates you dislike, X and Y, are the first choice of 40% and 25% of people respectively, and then A and B split the remainder evenly. X and Y are the two extremists -- on opposite sides of each other, with the moderates A and B in the middle. You favor A but A leans in the direction of X and B leans in the direction of Y.
If B is eliminated first then half of B's support goes A but half goes to Y, Y is still ahead of A and then A is eliminated next. If A -- your preferred candidate -- is eliminated first, half their support goes to B and the other half to X but Y gets nothing. Y then loses to B and the final round is X vs. B rather than X vs. Y. And the elimination of Y puts all their support behind B since X is the opposite extreme. But only if you rank B above A even though that's not what you'd have preferred.
> Yeah that's a real issue, and I'd want to use condorcet methods to fix that.
But now you're no longer using RCV/IRV. Score voting is a Condorcet method.
> Meanwhile with approval or score voting, a lot of people pretend not to like the other party's moderate because they're trying to get their side to win and it gets really messy.
Except that doesn't really help them because doing that also makes it more likely that their least favorite candidate wins, which is a significant incentive not to do it. The only reason to do that is if you're confident your favored candidate could only lose to your second choice, in which case it was really a two candidate race to begin with.
> Is there a need to have multiple candidates per party? If there is, a two stage election that picks party first and then picks probably-the-moderate is probably better than anything.
It doesn't matter if they're in the same party or not. If you're using a voting system that allows more than two parties to be viable then you'll have similar candidates running from similar parties. "Force the election to be one candidate from each of two major parties" is FPTP and it's terrible.
1 reply →