Congrats on your win in Fargo! Here are some thoughts.
Like you, I favor approval voting over IRV (based on a cursory assessment). However, I actually like the idea of some states using approval voting and some states using IRV. My feeling is that every voting method, including approval voting/score voting, likely has its own set of flaws. Some flaws may only become apparent when the method is used in a sequence of large elections over an extended period of time, as strategic voting, polling behavior, party politics, and election coverage reach an equilibrium.
In machine learning, a common strategy to improve performance is to make use of a collection of different machine learning algorithms. The idea is that any individual algorithm makes mistakes, but by taking the average output across all the different algorithms, individual mistakes often cancel each other out. In the same way, if different states make use of different voting methods, hopefully the flaws in each individual voting method will tend to cancel each other out. The best strategy becomes being the best candidate possible instead of trying to game an array of different voting systems simultaneously.
(This doesn’t diminish the urgency of making sure that a decent proportion of the electorate makes use of approval voting. Just saying it might not be a tragedy if IRV gets a decent fraction of the vote share, and IRV/approval voting advocates should work together to expand use of better voting systems, especially in swing states! Actually, speaking of swing states, is there any technique that could be used by a state to allocate its electoral votes strategically? Suppose Gary Johnson gets the most approvals in Florida. Seems like Florida residents could be pretty upset by their electoral votes being “thrown away” if Johnson isn’t given electoral votes by any other state. Is their any legal provision for Florida waiting until other states have had their electoral votes allocated before they get allocated in Florida? Though, even if there is, this gets complicated if multiple states were using such a procedure...)
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Another random thought. Has anyone studied the properties of the following “instant elimination voting” procedure:
Figure out which candidate was ranked last by the largest number of voters.
Eliminate that candidate. For every voter who ranked that candidate last, their second-to-last choice is now treated as their last choice.
Repeat until all but one candidate has been eliminated.
I presented it as IRV in reverse, but one can imagine variants. The objective here is to minimize our probability of electing a heavily disliked candidate as opposed to maximize our probability of electing a heavily liked candidate. IMO this is a reasonable objective—I suspect in general, it’s easier for a bad candidate to do a lot of harm than a good candidate to do a lot of good.
I know “disapproval voting” is mathematically equivalent to approval voting, but it seems like from a behavioral economics standpoint, they might not be equivalent. If disapproval voting causes voters to “default approve” candidates they’re unfamiliar with, and approval voting causes voters to “default disapprove” candidates they’re unfamiliar with (see: research into opt-in vs opt-out organ donation), that suggests obscure 3rd party or independent compromise candidates will do better in disapproval voting. Not sure if this is a good or bad thing. And I suppose a reddit style upvote/downvote scheme would average out the biases of disapproval and approval voting.
For every voter who ranked that candidate last, their second-to-last choice is now treated as their last choice.
That’s not Coomb’s method, but might be equivalent? I’m a little confused by this. Remember that after that candidate is eliminated, they are removed from all ballots, not just the ones that listed them last.
On a mix of voting methods being used across states
I think this mixed approach is good. I wouldn’t worry about IRV not getting a foothold here though. My worry is IRV taking over the map. Also, there are other places that use IRV like Australia. To my knowledge, there’s been limited research on international and US IRV data. That could change once we have our director of research position.
Approval voting in presidential elections.
I’d point to the FAQ on presidential elections here. If you’re using approval voting, it should be part of the national popular vote. Otherwise, you get strange tactics coming up.
IRV variants & variants in general
One way to evaluate the performance of a voting method in electing a good winner is to use simulations. You have a computer take different conditions like candidate scenarios or different kinds of voters (you might call these dials) and then run these elections millions of times. Then you can see how much of the maximum utility was captured by the voting method.
We’re dealing with a model here, so there are assumptions that will vary from simulation to simulation. But in the models I’ve seen, approval voting fares well even with tactical voters, particularly against IRV and way better than the choose-one method. Also, there is a “magical best” in these simulations. That is, the “magical best” voting method magically picks the winner in each election that maximizes voter utility. “Magical best” is the unattainable ceiling of voting method performance in choosing a good winner.
That “magical best” mark is not terribly far away from approval voting’s mark. And you could get some small but likely meaningful increases by going from approval to score/range voting. Once you’re at score voting though, there’s not a lot to be gained.
And it’s because there’s little utility to be gained beyond score voting (and not much even beyond approval) that I don’t get particularly excited about the fanciest idea of a new voting method. And believe me, I hear all kinds of those ideas. I’ve actually gotten phone calls from random people on the weekend concerning this before.
The point is, we have some voting methods like approval that do really well in electing high-utility winners that are so easy. And not only is it easy but it has perks like giving an accurate reflection of support for losing candidates. And it is precinct summable and easily auditable. These factors are important. It’s not just about maximizing utility from the winner. A voting method has other jobs, too. (See the FAQ on how to evaluate a voting method.)
In terms of CES mission strategy, score voting is really the only other single-winner voting method that makes sense for us to try because it has so much simplicity going for it as well. It just has some small implementation hurdles and slightly more complexity that approval voting doesn’t have. But it’ll likely be a little bit before we consider anything with score voting, and it’ll have to be a strategic target. One step at a time, as they say.
Congrats on your win in Fargo! Here are some thoughts.
Like you, I favor approval voting over IRV (based on a cursory assessment). However, I actually like the idea of some states using approval voting and some states using IRV. My feeling is that every voting method, including approval voting/score voting, likely has its own set of flaws. Some flaws may only become apparent when the method is used in a sequence of large elections over an extended period of time, as strategic voting, polling behavior, party politics, and election coverage reach an equilibrium.
In machine learning, a common strategy to improve performance is to make use of a collection of different machine learning algorithms. The idea is that any individual algorithm makes mistakes, but by taking the average output across all the different algorithms, individual mistakes often cancel each other out. In the same way, if different states make use of different voting methods, hopefully the flaws in each individual voting method will tend to cancel each other out. The best strategy becomes being the best candidate possible instead of trying to game an array of different voting systems simultaneously.
(This doesn’t diminish the urgency of making sure that a decent proportion of the electorate makes use of approval voting. Just saying it might not be a tragedy if IRV gets a decent fraction of the vote share, and IRV/approval voting advocates should work together to expand use of better voting systems, especially in swing states! Actually, speaking of swing states, is there any technique that could be used by a state to allocate its electoral votes strategically? Suppose Gary Johnson gets the most approvals in Florida. Seems like Florida residents could be pretty upset by their electoral votes being “thrown away” if Johnson isn’t given electoral votes by any other state. Is their any legal provision for Florida waiting until other states have had their electoral votes allocated before they get allocated in Florida? Though, even if there is, this gets complicated if multiple states were using such a procedure...)
---
Another random thought. Has anyone studied the properties of the following “instant elimination voting” procedure:
Figure out which candidate was ranked last by the largest number of voters.
Eliminate that candidate. For every voter who ranked that candidate last, their second-to-last choice is now treated as their last choice.
Repeat until all but one candidate has been eliminated.
I presented it as IRV in reverse, but one can imagine variants. The objective here is to minimize our probability of electing a heavily disliked candidate as opposed to maximize our probability of electing a heavily liked candidate. IMO this is a reasonable objective—I suspect in general, it’s easier for a bad candidate to do a lot of harm than a good candidate to do a lot of good.
I know “disapproval voting” is mathematically equivalent to approval voting, but it seems like from a behavioral economics standpoint, they might not be equivalent. If disapproval voting causes voters to “default approve” candidates they’re unfamiliar with, and approval voting causes voters to “default disapprove” candidates they’re unfamiliar with (see: research into opt-in vs opt-out organ donation), that suggests obscure 3rd party or independent compromise candidates will do better in disapproval voting. Not sure if this is a good or bad thing. And I suppose a reddit style upvote/downvote scheme would average out the biases of disapproval and approval voting.
That’s Coomb’s method, and it generally works better than IRV, but has strategy-susceptibility problems.
That’s not Coomb’s method, but might be equivalent? I’m a little confused by this. Remember that after that candidate is eliminated, they are removed from all ballots, not just the ones that listed them last.
On a mix of voting methods being used across states
I think this mixed approach is good. I wouldn’t worry about IRV not getting a foothold here though. My worry is IRV taking over the map. Also, there are other places that use IRV like Australia. To my knowledge, there’s been limited research on international and US IRV data. That could change once we have our director of research position.
Approval voting in presidential elections.
I’d point to the FAQ on presidential elections here. If you’re using approval voting, it should be part of the national popular vote. Otherwise, you get strange tactics coming up.
IRV variants & variants in general
One way to evaluate the performance of a voting method in electing a good winner is to use simulations. You have a computer take different conditions like candidate scenarios or different kinds of voters (you might call these dials) and then run these elections millions of times. Then you can see how much of the maximum utility was captured by the voting method.
We’re dealing with a model here, so there are assumptions that will vary from simulation to simulation. But in the models I’ve seen, approval voting fares well even with tactical voters, particularly against IRV and way better than the choose-one method. Also, there is a “magical best” in these simulations. That is, the “magical best” voting method magically picks the winner in each election that maximizes voter utility. “Magical best” is the unattainable ceiling of voting method performance in choosing a good winner.
That “magical best” mark is not terribly far away from approval voting’s mark. And you could get some small but likely meaningful increases by going from approval to score/range voting. Once you’re at score voting though, there’s not a lot to be gained.
And it’s because there’s little utility to be gained beyond score voting (and not much even beyond approval) that I don’t get particularly excited about the fanciest idea of a new voting method. And believe me, I hear all kinds of those ideas. I’ve actually gotten phone calls from random people on the weekend concerning this before.
The point is, we have some voting methods like approval that do really well in electing high-utility winners that are so easy. And not only is it easy but it has perks like giving an accurate reflection of support for losing candidates. And it is precinct summable and easily auditable. These factors are important. It’s not just about maximizing utility from the winner. A voting method has other jobs, too. (See the FAQ on how to evaluate a voting method.)
In terms of CES mission strategy, score voting is really the only other single-winner voting method that makes sense for us to try because it has so much simplicity going for it as well. It just has some small implementation hurdles and slightly more complexity that approval voting doesn’t have. But it’ll likely be a little bit before we consider anything with score voting, and it’ll have to be a strategic target. One step at a time, as they say.
(Bayesian Regret example for reference)