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> You don’t have to game theory your choice of the lesser of two evils, you rank who you prefer You "have" [1] to game-theory your choice no matter what the vo

> You don’t have to game theory your choice of the lesser of two evils, you rank who you prefer You "have" [1] to game-theory your choice no matter what the voting system is. Ranked-choice is apparently believed [2] to be less susceptible to tactical voting than some other systems, though. (Not sure if this is quantitative or qualitative.) > IRV may incentivize forms of tactical voting (such as compromising) when voters have sufficient information about other voters' preferences, such as from accurate pre-election polling. FairVote mentions that monotonicity failure can lead to situations where "having more voters rank [a] candidate first, can cause [the candidate] to switch from being a winner to being a loser." [1] https://homepage.cs.uiowa.edu/~dwjones/voting/4980.2020/projects/zhang.pdf https://homepage.cs.uiowa.edu/~dwjones/voting/4980.2020/proj... [2] https://en.wikipedia.org/wiki/Instant-runoff_voting#Tactical_voting https://en.wikipedia.org/wiki/Instant-runoff_voting#Tactical...

eru 4y ago
Yes, at best a voting system can make it so that your naive intuition is pretty close to your best tactical voting. Approval voting and range voting come pretty close. However, your first link only seems to critique deterministic voting systems. It's fairly easy to sidestep these critiques (especially Arrow's theorem) with a probabilistic systems: Eg this variant of sortition: every voter chooses a preferred candidate on their ballot, and we draw n ballots at random to fill up parliament. (Pick whatever system you prefer for resolving one candidate getting picked multiple times, eg give them extra voting power in parliament, or pick the voter's next choice on the ballot etc.) If you can find a way to vote 'tactically' in this scheme, please let me know. I believe it's fair in some sense, and free of the pathologies outlined in your links. You are always better off voting for the candidate you prefer. (I specifically mention using this scheme to fill up parliament with a few hundred people in it. If you want to pick a single position, like a president, the low of large numbers won't kick in, and you might have a greater variance than you'd like from your voting system. But even for picking a president, a randomised system can still avoid the pathologies mentioned.)
- thaumasiotes 4y ago
  > Pick whatever system you prefer for resolving one candidate getting picked multiple times, eg give them extra voting power in parliament That is a really interesting idea.
  - vintermann 4y ago
    But it quickly shows another problem: share of votes in parliament, is not equal to share of power in parliament. Picture a body where there's 4 members. A has a voting power of 12. B and C have a voting power of 8 each. D has a voting power of 3. It's easy to see that once A, B and C have cast their yes/no vote, the issue will be decided no matter how D votes. D has a share in "voting weight", but no power at all. We can say this for sure without knowing anything about the ideology of the participants.
    - thaumasiotes 4y ago
      That problem occurs in exactly the same way on any vote in a "normal" parliament where party affiliation determines vote. > D has a share in "voting weight", but no power at all. We can say this for sure This is interesting in a different way. D's ability to vote has no power at all. That's true. You're taking a leap when you extrapolate that D has no power; by that argument, lobbyists have no power either. Is that something you believe?
      - eru 4y ago
        > That problem occurs in exactly the same way on any vote in a "normal" parliament where party affiliation determines vote. It also occurs under most 'normal' voting systems in safe seats.
      - vintermann 4y ago
        Lobbyists have power through money and networks. If a non-pivotal voter has power, it's likewise through something else than his vote. That this is a problem with party whipping in parliaments too, doesn't mean it's not a problem.

eru 4y ago

Yes, at best a voting system can make it so that your naive intuition is pretty close to your best tactical voting. Approval voting and range voting come pretty close. However, your first link only seems to critique deterministic voting systems. It's fairly easy to sidestep these critiques (especially Arrow's theorem) with a probabilistic systems: Eg this variant of sortition: every voter chooses a preferred candidate on their ballot, and we draw n ballots at random to fill up parliament. (Pick whatever system you prefer for resolving one candidate getting picked multiple times, eg give them extra voting power in parliament, or pick the voter's next choice on the ballot etc.) If you can find a way to vote 'tactically' in this scheme, please let me know. I believe it's fair in some sense, and free of the pathologies outlined in your links. You are always better off voting for the candidate you prefer. (I specifically mention using this scheme to fill up parliament with a few hundred people in it. If you want to pick a single position, like a president, the low of large numbers won't kick in, and you might have a greater variance than you'd like from your voting system. But even for picking a president, a randomised system can still avoid the pathologies mentioned.)

thaumasiotes 4y ago
> Pick whatever system you prefer for resolving one candidate getting picked multiple times, eg give them extra voting power in parliament That is a really interesting idea.
- vintermann 4y ago
  But it quickly shows another problem: share of votes in parliament, is not equal to share of power in parliament. Picture a body where there's 4 members. A has a voting power of 12. B and C have a voting power of 8 each. D has a voting power of 3. It's easy to see that once A, B and C have cast their yes/no vote, the issue will be decided no matter how D votes. D has a share in "voting weight", but no power at all. We can say this for sure without knowing anything about the ideology of the participants.
  - thaumasiotes 4y ago
    That problem occurs in exactly the same way on any vote in a "normal" parliament where party affiliation determines vote. > D has a share in "voting weight", but no power at all. We can say this for sure This is interesting in a different way. D's ability to vote has no power at all. That's true. You're taking a leap when you extrapolate that D has no power; by that argument, lobbyists have no power either. Is that something you believe?
    - eru 4y ago
      > That problem occurs in exactly the same way on any vote in a "normal" parliament where party affiliation determines vote. It also occurs under most 'normal' voting systems in safe seats.
    - vintermann 4y ago
      Lobbyists have power through money and networks. If a non-pivotal voter has power, it's likewise through something else than his vote. That this is a problem with party whipping in parliaments too, doesn't mean it's not a problem.