5 ms·

Two reasons: Arrow’s impossibility theorem and the fact that people are not perfect logicians. I honestly thought that after learning Arrow’s impossibility the

Two reasons: Arrow’s impossibility theorem and the fact that people are not perfect logicians. I honestly thought that after learning Arrow’s impossibility theorem that Condorcet is not especially important. Since we can’t have a perfect voting system, we have to pick an imperfect one, and among the alternatives, it’s important to capture information from voters. Instant runoff captures a lot of information. Approval voting I think is much too tactical and, strictly speaking, worse than IRV. No contest. IRV lets people express their preferences in a fairly understandable way. The strategy I see people talking about is “rank all the front-runners, and use the leftover spots to rank the people you want to win, even if they’re not likely to win.” So if A B C and D are front-runners, and E and F are the two other candidates you like, you come up with a ranking for those six and put the top five on your ballot. The idea that people who like this system are “dangerously misinformed” or “dishonest” is needlessly inflammatory.

godelski 5y ago
> Arrow’s impossibility theorem First off, Arrow's doesn't apply to all systems. You'll need to look into both Gibbard's and Gibbard-Satterthwaite's theorems. Second off, just because you can't find a global optimization in a highly dimensional space doesn't mean there aren't local optimizations along criteria we care more about. Appealing to Arrow's is a cop-out. > Approval voting I think is much too tactical and, strictly speaking, worse than IRV. No contest. You're going to have to back this up with some strong evidence. Approval has higher VSE, is simpler, is more resistant to spoilers and tactical voting. > IRV lets people express their preferences in a fairly understandable way. Actually your argument holds true for any ordinal or cardinal system. Cardinal even having more flexibility since you can give two candidates the same score. And in cardinal if you want to rank your candidates, no problem. Better yet, you have better encoding opportunities because you can specify the distance between your ranking instead of the uniform spacing that ordinal systems force upon you. (BTW, given what the person above you wrote, I would assume that they know how ranked voting works and explaining how it is going to come off as you calling them dumb).
- klodolph 5y ago
  I disagree that cardinal voting is understandable. It’s how we rate restaurants and review products on Amazon, and I don’t think it translates to an election with multiple options. The issue here is not just how logical humans “homo economicus” behaves, but how actual voters behave. Not really interested in engaging with the rest of this comment right now, but suffice it to say that I don’t think you’re accounting for human behavior in practice, which is messy and illogical. I don’t think it’s reasonable to say that I’m appealing to Arrow’s impossibility theorem as a cop-out—I’m saying that since we don’t have a game theoretic solution the the problem, we should look at the actual behavior of imperfect, irrational humans as the deciding factor.
  - godelski 5y ago
    > I disagree that cardinal voting is understandable. It’s how we rate restaurants and review products on Amazon, and I don’t think it translates to an election with multiple options. I disagree but also don't see this as a problem. If you rank candidates you still get the majority of the desirable properties. Rank with non-equal distances, even better. Hell, it isn't even bad if you bullet vote (that's just approval voting). Investigating non-optimal ways of voting under any voting system is an extremely important analysis. So for the voter there is no problem. I'm also kinda put off that you give real world examples of humans using cardinal methods and then claiming that we can't understand it (HN is using cardinal voting...) But we also have to consider the counting of votes side of "understandable." Plurality is pretty damn easy, and this is clearly why we use it. Approval is almost as easy (just just sum multiple columns). Range/Score isn't much harder. Then STAR introduces 2 rounds of counting. Then we look at IRV and we see that we have tons of rounds. This isn't typically so bad in a presidential election where there are realistically about 4 candidates, but that complexity increases real fast elsewhere. Just watch NYC. There's going to be at least 5 rounds (probably more). This is far more complex. We only have to look at Arizona to understand why this part of the "understandable" question is important.
- magila 5y ago
  One big problem with approval voting is that it presents voters with a difficult conundrum: what do you do with candidates you don't particularly like but would still strongly prefer over one-or-more other candidates? If people are too lenient with their approval it increases the risk of someone no one really likes getting elected over someone a majority would have preferred. If people are too stringent you start running into the same problems as FTTP. Approval voting has some nice mathematical properties, but I think in practice trying to pidgeon hole people's preferences into a binary decision would be a major source of voter frustration and lead to tactical voting.
jeff_tyrrill 5y ago
I wouldn't choose to use the word "dishonest" but I sympathize - in nearly all news media explanations of "ranked choice voting", the description solely explains instant runoff, and makes no mention whatsoever that there is a choice of algorithm that comes with the choice to use ranked ballots, such as Condorcet. The words "instant runoff" are almost never mentioned. Choice of language matters, and "ranked choice voting" (to solely mean "instant runoff voting") is a conceptually misleading term meant to load the debate. It dis-educates rather than educates on how voting systems work. Advocates of other voting systems have to first start out by explaining this misdirection and unpacking the wrong mental model, then get to the merits of one voting system vs. another - because people have been told that "ranked choice voting" works a certain way and only a certain way.
- klodolph 5y ago
  I’d say that part of the cost of switching voting systems is educating voters how the new system works. Many voters simply don’t care about the finer details and just have a couple desiderata—we want to have our vote count, and we want to be able to vote for our favorite candidate. Instant runoff is super easy to explain and achieves those desiderata, at least to some extent. It’s hard to quantify the differences in mathematical terms against soft concerns like “we can educate voters and explain how this system works”. For that reason, I would like to see a non-mathematical argument against IRV, one that accounts for the other half of the voting problem.
  - abecedarius 5y ago
    I'm always baffled by this claim that simple explanations favor instant runoff. Here's approval voting: "Upvote the candidates you like. The candidate with the most total votes wins." It's not just mathematically simpler, it's simpler in informal terms, a smaller change from current plurality voting, and it seems less messy in the strategic dynamics insofar as we've tested these different systems for real.
    - godelski 5y ago
      Even score voting is easier than IRV. You can rank if you want to. But you can better specify preference because you're not ranking with the same preferential distance between candidates and people. We use score all over the place (we could call Hacker News score voting with a small range: -1/0/+1).
ClayShentrup 5y ago
> Approval voting I think is much too tactical and, strictly speaking, worse than IRV. On the contrary, approval voting gets better results than IRV with any measure of strategic or honest voters. See extensive computer simulation results by Harvard stats PhD and voting methods expert Jameson Quinn. Brown (50/50) is probably the most realistic setting. https://rpubs.com/Jameson-Quinn/VSE5key https://rpubs.com/Jameson-Quinn/VSE5key A simple example of IRV strategy is next year's Alaska senate race. Murkowski would beat either rival head-to-head but is likely to be eliminated based on first-place votes. So Democrats want to strategically rank Murkowski 1st in order to help her survive to beat Tshibaka (Trump Republican) so they at least get their lesser evil. Here's a good comparison of approval voting vs. IRV by experts. Full disclosure, I was a CES co-founder and have written extensively on this topic for 15 years. https://electionscience.org/library/approval-voting-versus-irv/ https://electionscience.org/library/approval-voting-versus-i... > I honestly thought that after learning Arrow’s impossibility theorem that Condorcet is not especially important. I've visited Kenneth Arrow at his home and co-founded a non-profit that interviewed him. His theorem only applies to social welfare functions, not voting methods, if properly understood. But if anything, the moral is to AVOID ranked voting methods and instead use rated voting methods. https://www.rangevoting.org/ArrowThm https://www.rangevoting.org/ArrowThm
- cosmojg 5y ago
  For those who want to better understand VSE simulations and those who want to compare even more voting methods, see: http://electionscience.github.io/vse-sim/VSE/ http://electionscience.github.io/vse-sim/VSE/
  - godelski 5y ago
    Or if you want to see an animated version narrated by the gp of this comment (Clay) see this: https://www.youtube.com/watch?v=-4FXLQoLDBA https://www.youtube.com/watch?v=-4FXLQoLDBA
- asdfaoeu 5y ago
  > On the contrary, approval voting gets better results than IRV with any measure of strategic or honest voters. See extensive computer simulation results by Harvard stats PhD and voting methods expert Jameson Quinn. Brown (50/50) is probably the most realistic setting. If you look at the graph with the honest strategy you get better results with IRV which is basically his point.
logicchop 5y ago
> IRV lets people express their preferences in a fairly understandable way. The strategy I see... That's the concern though. You likely don't want to just "express your preferences." You need to strategically rank candidates. But then what are you being asked to do exactly when you go to vote? I don't think it would fly if the instructions on the ballot gave you guidance on how to "strategize" your rankings. But if it doesn't give that guidance, it's misleading. And I understand that all voting mechanisms have their own unique pitfalls; so we have to fall back to pragmatic questions. And one major pragmatic question is: What's the status-quo/What is everyone already accustomed to? Asking a large voting body to switch methods is not easy and I think it's being motivated largely by a misleading "grass-is-greener" claim about rank voting.

godelski 5y ago

> Arrow’s impossibility theorem First off, Arrow's doesn't apply to all systems. You'll need to look into both Gibbard's and Gibbard-Satterthwaite's theorems. Second off, just because you can't find a global optimization in a highly dimensional space doesn't mean there aren't local optimizations along criteria we care more about. Appealing to Arrow's is a cop-out. > Approval voting I think is much too tactical and, strictly speaking, worse than IRV. No contest. You're going to have to back this up with some strong evidence. Approval has higher VSE, is simpler, is more resistant to spoilers and tactical voting. > IRV lets people express their preferences in a fairly understandable way. Actually your argument holds true for any ordinal or cardinal system. Cardinal even having more flexibility since you can give two candidates the same score. And in cardinal if you want to rank your candidates, no problem. Better yet, you have better encoding opportunities because you can specify the distance between your ranking instead of the uniform spacing that ordinal systems force upon you. (BTW, given what the person above you wrote, I would assume that they know how ranked voting works and explaining how it is going to come off as you calling them dumb).

klodolph 5y ago
I disagree that cardinal voting is understandable. It’s how we rate restaurants and review products on Amazon, and I don’t think it translates to an election with multiple options. The issue here is not just how logical humans “homo economicus” behaves, but how actual voters behave. Not really interested in engaging with the rest of this comment right now, but suffice it to say that I don’t think you’re accounting for human behavior in practice, which is messy and illogical. I don’t think it’s reasonable to say that I’m appealing to Arrow’s impossibility theorem as a cop-out—I’m saying that since we don’t have a game theoretic solution the the problem, we should look at the actual behavior of imperfect, irrational humans as the deciding factor.
- godelski 5y ago
  > I disagree that cardinal voting is understandable. It’s how we rate restaurants and review products on Amazon, and I don’t think it translates to an election with multiple options. I disagree but also don't see this as a problem. If you rank candidates you still get the majority of the desirable properties. Rank with non-equal distances, even better. Hell, it isn't even bad if you bullet vote (that's just approval voting). Investigating non-optimal ways of voting under any voting system is an extremely important analysis. So for the voter there is no problem. I'm also kinda put off that you give real world examples of humans using cardinal methods and then claiming that we can't understand it (HN is using cardinal voting...) But we also have to consider the counting of votes side of "understandable." Plurality is pretty damn easy, and this is clearly why we use it. Approval is almost as easy (just just sum multiple columns). Range/Score isn't much harder. Then STAR introduces 2 rounds of counting. Then we look at IRV and we see that we have tons of rounds. This isn't typically so bad in a presidential election where there are realistically about 4 candidates, but that complexity increases real fast elsewhere. Just watch NYC. There's going to be at least 5 rounds (probably more). This is far more complex. We only have to look at Arizona to understand why this part of the "understandable" question is important.
magila 5y ago
One big problem with approval voting is that it presents voters with a difficult conundrum: what do you do with candidates you don't particularly like but would still strongly prefer over one-or-more other candidates? If people are too lenient with their approval it increases the risk of someone no one really likes getting elected over someone a majority would have preferred. If people are too stringent you start running into the same problems as FTTP. Approval voting has some nice mathematical properties, but I think in practice trying to pidgeon hole people's preferences into a binary decision would be a major source of voter frustration and lead to tactical voting.

jeff_tyrrill 5y ago

I wouldn't choose to use the word "dishonest" but I sympathize - in nearly all news media explanations of "ranked choice voting", the description solely explains instant runoff, and makes no mention whatsoever that there is a choice of algorithm that comes with the choice to use ranked ballots, such as Condorcet. The words "instant runoff" are almost never mentioned. Choice of language matters, and "ranked choice voting" (to solely mean "instant runoff voting") is a conceptually misleading term meant to load the debate. It dis-educates rather than educates on how voting systems work. Advocates of other voting systems have to first start out by explaining this misdirection and unpacking the wrong mental model, then get to the merits of one voting system vs. another - because people have been told that "ranked choice voting" works a certain way and only a certain way.

klodolph 5y ago
I’d say that part of the cost of switching voting systems is educating voters how the new system works. Many voters simply don’t care about the finer details and just have a couple desiderata—we want to have our vote count, and we want to be able to vote for our favorite candidate. Instant runoff is super easy to explain and achieves those desiderata, at least to some extent. It’s hard to quantify the differences in mathematical terms against soft concerns like “we can educate voters and explain how this system works”. For that reason, I would like to see a non-mathematical argument against IRV, one that accounts for the other half of the voting problem.
- abecedarius 5y ago
  I'm always baffled by this claim that simple explanations favor instant runoff. Here's approval voting: "Upvote the candidates you like. The candidate with the most total votes wins." It's not just mathematically simpler, it's simpler in informal terms, a smaller change from current plurality voting, and it seems less messy in the strategic dynamics insofar as we've tested these different systems for real.
  - godelski 5y ago
    Even score voting is easier than IRV. You can rank if you want to. But you can better specify preference because you're not ranking with the same preferential distance between candidates and people. We use score all over the place (we could call Hacker News score voting with a small range: -1/0/+1).

ClayShentrup 5y ago

> Approval voting I think is much too tactical and, strictly speaking, worse than IRV. On the contrary, approval voting gets better results than IRV with any measure of strategic or honest voters. See extensive computer simulation results by Harvard stats PhD and voting methods expert Jameson Quinn. Brown (50/50) is probably the most realistic setting. https://rpubs.com/Jameson-Quinn/VSE5key https://rpubs.com/Jameson-Quinn/VSE5key A simple example of IRV strategy is next year's Alaska senate race. Murkowski would beat either rival head-to-head but is likely to be eliminated based on first-place votes. So Democrats want to strategically rank Murkowski 1st in order to help her survive to beat Tshibaka (Trump Republican) so they at least get their lesser evil. Here's a good comparison of approval voting vs. IRV by experts. Full disclosure, I was a CES co-founder and have written extensively on this topic for 15 years. https://electionscience.org/library/approval-voting-versus-irv/ https://electionscience.org/library/approval-voting-versus-i... > I honestly thought that after learning Arrow’s impossibility theorem that Condorcet is not especially important. I've visited Kenneth Arrow at his home and co-founded a non-profit that interviewed him. His theorem only applies to social welfare functions, not voting methods, if properly understood. But if anything, the moral is to AVOID ranked voting methods and instead use rated voting methods. https://www.rangevoting.org/ArrowThm https://www.rangevoting.org/ArrowThm

cosmojg 5y ago
For those who want to better understand VSE simulations and those who want to compare even more voting methods, see: http://electionscience.github.io/vse-sim/VSE/ http://electionscience.github.io/vse-sim/VSE/
- godelski 5y ago
  Or if you want to see an animated version narrated by the gp of this comment (Clay) see this: https://www.youtube.com/watch?v=-4FXLQoLDBA https://www.youtube.com/watch?v=-4FXLQoLDBA
asdfaoeu 5y ago
> On the contrary, approval voting gets better results than IRV with any measure of strategic or honest voters. See extensive computer simulation results by Harvard stats PhD and voting methods expert Jameson Quinn. Brown (50/50) is probably the most realistic setting. If you look at the graph with the honest strategy you get better results with IRV which is basically his point.

logicchop 5y ago

> IRV lets people express their preferences in a fairly understandable way. The strategy I see... That's the concern though. You likely don't want to just "express your preferences." You need to strategically rank candidates. But then what are you being asked to do exactly when you go to vote? I don't think it would fly if the instructions on the ballot gave you guidance on how to "strategize" your rankings. But if it doesn't give that guidance, it's misleading. And I understand that all voting mechanisms have their own unique pitfalls; so we have to fall back to pragmatic questions. And one major pragmatic question is: What's the status-quo/What is everyone already accustomed to? Asking a large voting body to switch methods is not easy and I think it's being motivated largely by a misleading "grass-is-greener" claim about rank voting.