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by ekimekim 539 days ago
Being vulnerable to strategic voting is a huge downside that outweighs other considerations.

As the article mentions, in the real world score voting would just be approval voting where you put a max score on some choices and 0 on others.

And in approval voting you need to think about how others will vote and pick your cutoff point based on who you think has a chance - do you vote "yes" for the center-right party to avoid the hard right party getting in? Or do you vote "no" to help the center-left party beat the center-right party? (swap those directions to personal preference)

RCV isn't perfect, but in all but the smallest elections there's really no practical strategic voting considerations. You just state your true preference order.

Of course, I'll take any of them over FPTP.

2 comments

> Being vulnerable to strategic voting is a huge downside that outweighs other considerations.

I disagree that strategic voting as a downside outweighs the downsides of RCV or FPTP - especially when FPTP itself is susceptible to strategic voting, too. None of the three satisfy the condorcet winner criterion (that is: none of them guarantee the winner would beat every other candidate head-to-head), but it seems less likely / more contrived for score/approval voting to fail it.

> And in approval voting you need to think about how others will vote and pick your cutoff point based on who you think has a chance - do you vote "yes" for the center-right party to avoid the hard right party getting in? Or do you vote "no" to help the center-left party beat the center-right party? (swap those directions to personal preference)

That's why I'd personally go with a simple three-level score vote: "yeah", "meh", or "nah". If people really want to shoot themselves in the foot by ignoring the "meh" option, then so be it, but at least the option is there for people to vote "meh" for candidates that are merely acceptable/tolerable (and reserve "yeah" for ideal candidates and "nah" for unacceptable/intolerable candidates).

> I disagree that strategic voting as a downside outweighs the downsides of RCV or FPTP - especially when FPTP itself is susceptible to strategic voting, too.

To clarify, I never intended that as a defence of FPTP. It's awful and I'll take any of the systems being discussed here over it. It was a statement specifically towards IRV over score/approval.

there is no good argument for IRV over score/approval. score and approval blow IRV out of the water on literally every single metric that matters. they're simpler, more accurate (with any ratio of strategic or honest voters), and more transparent and fair to minor party candidates.

https://clayshentrup.medium.com/later-no-harm-72c44e145510

it's not even close.

> there is no good argument for IRV over score/approval

Score voting calls for ambiguous, proven-to-be-culturally-variable ratings that have no natural relationship to preferences (and approval does the same thing in an opposite way, while score voting relies on ambiguous distinctions that don’t have a clear mapping from actual preferences, approval forces voters to rank with artificial ties that don’t have a clear mapping to actual preferences); most metrics simply do not reflect this because they have no mechanism to.

Where these problems don’t apply, as is the case many places outside of secret ballots for elections of public officers, score and approval can be great. E.g., open ballot approval on a choice of a group activity where voting “approve” is a commitment to participate if the selected option wins makes perfect sense, or open-ballot score voting where the given score is a commitment to provide some quantity of resources proportional to the score to the common effort if the item given that score wins. Then the ratings given are tied to concrete differences in preferences.

(On the other hand, choosing between single-winner ballot methods is mostly a waste of time regardless of the abstract merits of the particular system; the most significant difference within democratic systems in quality of government by popular engagement, popular satisfaction with government, and a number of other measures is with the degree of proportionality of the main legislative body, and no single-winner system is going to deliver much of an improvement there, you need a system designed for proportionality, which means multimember districts on some level.)

> Score voting calls for ambiguous, proven-to-be-culturally-variable ratings that have no natural relationship to preferences

utter nonsense. the scores are just normalized utilities.

or, if you're being strategic, you're just min-maxing based on expected utility. https://www.rangevoting.org/RVstrat6

> (and approval does the same thing in an opposite way

utter nonsense. approval voting is just a binary 0-1 scale instead of e.g. 0-5. the math in no way changes.

> while score voting relies on ambiguous distinctions that don’t have a clear mapping from actual preferences

utterly false. there is nothing "ambiguous" whatsoever.

> approval forces voters to rank with artificial ties that don’t have a clear mapping to actual preferences

of course it has a mapping to actual preferences. what you're _trying_ to say is that the transform from utilities ("preferences") to scores is LOSSY. the problem is that transforming to ordinal rankings is even MORE lossy, and this is why approval voting still outperforms ranked methods in general, especially with strategic voting taken into account.

we have several pages explaining this common myth to laypersons.

https://medium.com/@clayshentrup/expressiveness-6ef8c034bc65

https://www.rangevoting.org/Expressiveness

> the most significant difference within democratic systems in quality of government by popular engagement, popular satisfaction with government, and a number of other measures is with the degree of proportionality of the main legislative body

there's absolutely no evidence for this. you're making the "proportional representation fallacy". i address this here.

https://clayshentrup.medium.com/the-proportional-representat...

so virtually everything you just said was incorrect. which is why it's good to study this issue and talk to experts before forming opinions.

there's nothing special about the condorcet criterion. it's mathematically proven that the most favored candidate can even be the condorcet _loser_. you just want the voting method with the highest voter satisfaction efficiency.

https://electionscience.github.io/vse-sim/

> As the article mentions, in the real world score voting would just be approval voting where you put a max score on some choices and 0 on others.

utterly false.

https://www.rangevoting.org/HonStrat https://www.rangevoting.org/Honesty https://www.rangevoting.org/RVstrat6

> And in approval voting you need to think about how others will vote and pick your cutoff point based on who you think has a chance

1. this is true of _every_ deterministic voting method. it's mathematically proven.

2. even approval voting is extremely accurate. see voter satisfaction efficiency calculations from harvard stats phd jameson quinn, who served with me on the board of the center for election science. https://electionscience.github.io/vse-sim/

> RCV isn't perfect, but in all but the smallest elections there's really no practical strategic voting considerations. You just state your true preference order.

ludicrous. IRV is extremely vulnerable to strategic voting. my aunt who voted biden even tho she preferred warren (to stop trump) would do the same thing with ranking: rank biden 1st to prevent warren from losing to trump.

something similar happened in the first alaska house special election. palin was a spoiler. she caused the democrat mary peltola to win, even tho fellow republican nick begich was preferred to peltola (and to palin) by a large majority. in other words, palins supporters hurt themselves by honestly ranking palin 1st. they would have been strategically better off burying palin and ranking begich 1st.

https://rcvchangedalaska.com/

and the VSE metrics show that even 100% honest IRV performs worse than approval voting with all voters being strategic.

IRV is simply one of the worst voting methods in existence. not to mention being radically overcomplicated and opaque.

i'm sorry that you posted this before having even an inkling about how any of this works.