• danA
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    3 hours ago

    It’s the only voting system in existence where ranking someone higher on the ballot can cause them to lose the election.

    Interesting… Do you have an example of this?

    • chaogomu@lemmy.world
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      2 hours ago

      https://medium.com/@Gbgrow/understanding-non-monotonicity-in-ranked-choice-voting-and-how-to-prevent-it-55ad54fdad06

      https://electionscience.org/research-hub/the-limits-of-ranked-choice-voting

      https://en.wikipedia.org/wiki/Negative_responsiveness_paradox#Specific_examples

      We’ve seen it happen in actual elections, as shown in the Wikipedia link.

      RCV is just a flawed system, which is expected for something created by a couple of guys 150+ years ago.

      • Sludgeyy@lemmy.world
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        3 minutes ago

        Disclaimer: I wrote this all for myself not to change your mind or argue. Helps if I write down my thoughts and I don’t see a problem sharing. Feel free to discuss if you like.

        35 voters: Alice > Carol > Bob 35 voters: Bob > Carol > Alice 30 voters: Carol > Alice > Bob

        Vs.

        41 voters: Alice > Carol > Bob 29 voters: Bob > Carol > Alice 30 voters: Carol > Alice > Bob

        Alice wins

        Vs.

        Carol wins

        Say you have:

        41 voters: Republican > Third-party > Democratic 29 voters: Third-party > Democratic > Republican 30 voters: Democratic > Third-party > Republican

        If those 29 voters couldn’t vote Third-party they would vote Democratic. So when the Third-party candidate is knocked out, their votes should favor their second pick. Democratic wins 59-41.

        If it was:

        41 voters: Republican > Third-party > Democratic 29 voters: Third-party > Republican > Democratic 30 voters: Democratic > Third-party > Republican

        Which makes more since on why the 6 votes moved to Republican because Republican was their second choice.

        Then Republicans win 70-30.

        In America you’d have 4 basic senarios

        25 voters: Republican > Third-party > Democratic 25 voters: Third-party > Democratic > Republican 25 voters: Third-party > Republican > Democratic 25 voters: Democratic > Third-party > Republican

        In RCV, Third-party wins.

        Let’s say this

        30 voters: Republican > Third-party > Democratic 25 voters: Third-party > Democratic > Republican 20 voters: Third-party > Republican > Democratic 25 voters: Democratic > Third-party > Republican

        Third-party still wins

        40 voters: Republican > Third-party > Democratic 10 voters: Third-party > Democratic > Republican 10 voters: Third-party > Republican > Democratic 40 voters: Democratic > Third-party > Republican

        It would be a tie

        45 voters: Republican > Third-party > Democratic 10 voters: Third-party > Democratic > Republican 5 voters: Third-party > Republican > Democratic 40 voters: Democratic > Third-party > Republican

        It would still be a tie

        45 voters: Republican > Third-party > Democratic 5 voters: Third-party > Democratic > Republican 10 voters: Third-party > Republican > Democratic 40 voters: Democratic > Third-party > Republican

        Republicans win

        Let’s change it to this:

        35 voters: Alice > Carol > Bob 35 voters: Bob > Alice > Carol 30 voters: Carol > Alice > Bob

        Vs.

        41 voters: Alice > Carol > Bob 29 voters: Bob > Alice > Carol 30 voters: Carol > Alice > Bob

        Alice wins

        Vs.

        Alice wins

        They couldn’t make their whole point if you just switched Alice and Carol. And it makes much more sense that someone with Alice second would change it to Alice first.

        But when 29 votes still hold Alice as last, it does have some weight.

        Something just seems off about it and it’s because they cherry picked a senario that would work for their point.

        Alice > Carol > Bob Alice > Bob > Carol Bob > Alice > Carol Bob > Carol > Alice Carol > Alice > Bob Carol > Bob > Alice

        There are 6 ways to vote and they leave out half of them. Then they make Carol supporters favor Alice as their second choice.

        20 voters: Alice > Carol > Bob 15 voters: Alice > Bob > Carol 15 voters: Bob > Alice > Carol 20 voters: Bob > Carol > Alice 20 voters: Carol > Alice > Bob 10 voters: Carol > Bob > Alice

        Carol eliminated, +10 Bob +20 Alice. Alice would win.

        If 5 voters from Bob > Alice > Carol were moved to Alice > Bob > Carol

        20 voters: Alice > Carol > Bob 20 voters: Alice > Bob > Carol 10 voters: Bob > Alice > Carol 20 voters: Bob > Carol > Alice 20 voters: Carol > Alice > Bob 10 voters: Carol > Bob > Alice

        Alice would win

        What if everyone from Bob > Alice > Carol moved to vote for Alice > Bob > Carol

        20 voters: Alice > Carol > Bob 30 voters: Alice > Bob > Carol 0 voters: Bob > Alice > Carol 20 voters: Bob > Carol > Alice 20 voters: Carol > Alice > Bob 10 voters: Carol > Bob > Alice

        It would be a tie.

        In bold are the three they selected:

        20 voters: Alice > Carol > Bob 15 voters: Alice > Bob > Carol 15 voters: Bob > Alice > Carol 20 voters: Bob > Carol > Alice 10 voters: Carol > Alice > Bob 20 voters: Carol > Bob > Alice

        5 voters from Bob > Carol > Alice moved to Alice > Carol > Bob. Just like their example.

        26 voters: Alice > Carol > Bob 15 voters: Alice > Bob > Carol 15 voters: Bob > Alice > Carol 14 voters: Bob > Carol > Alice 10 voters: Carol > Alice > Bob 20 voters: Carol > Bob > Alice

        Alice 41 Bob 28 Carol 30

        Bob is eliminated.

        15 votes goes to Alice. 14 goes to Carol.

        Alice still wins.

        But they set it up like:

        20 voters: Alice > Carol > Bob 15 voters: Alice > Bob > Carol 0 voters: Bob > Alice > Carol 35 voters: Bob > Carol > Alice 10 voters: Carol > Alice > Bob 20 voters: Carol > Bob > Alice

        5 voters from Bob > Carol > Alice moved to Alice > Carol > Bob. Just like their example.

        26 voters: Alice > Carol > Bob 15 voters: Alice > Bob > Carol 0 voters: Bob > Alice > Carol 29 voters: Bob > Carol > Alice 10 voters: Carol > Alice > Bob 20 voters: Carol > Bob > Alice

        Then when Bob is eliminated all 29 votes go to Carol.

        Then they say “It’s unfair that Carol wins”. When in reality those 29 people would prefer Carol over Alice.

        RCV might have some flaws but that article has some flaws.

        I haven’t looked at the others. I might later.

      • danA
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        32 minutes ago

        Thanks for the links. I appreciate it! Now I understand the issue.