Just getting rid of first-past-the-post would do wonders for our country and by the looks of it approval voting is inferior to run-off voting by a mile.
I'm curious why you think this? I think exactly the opposite. RCV/IRV has major problems, especially for strong spoilers. They are also more difficult to tabulate and with the recent events of the last election the importance of ease to tabulate went up in my priority list (making me even question my preference of score over approval). In fact, IRV also favors extremists, which is something I really don't want.
Another problem with RCV is that it’s difficult to understand, at least when you get into the runoffs. That makes it harder for people to understand and trust the election system, which is also very important.
This is one big issue for me with IRV vs Cardinal systems. Both handle _weak_ spoilers but IRV doesn't handle ''strong,, spoilers. Understanding that these are two different types of spoilers is really important. It is "Bernie vs Hillary" and "Cruz vs Trump." Even with IRV we'd still see the parties trying to prevent strong primary candidates from running independently because they could spoil the election. With cardinal methods (approval, score, star) this is far less of a concern and thus I think more democratic of an election. I honestly think we should be much more concerned with strong spoilers than weak spoilers (weak spoilers don't affect elections much anyways).
STAR: 5, Score 4, approval 4, IRV 1, FPTP 1
It would be ranked in this order too, but there's more expressivity here than an ordinal system can provide.
FWIW, this already happens. That will also happen under any system. I'm not sure why you think IRV encourages moderates. It actually encourages extremist candidates which is why I'm particularly against it.
IRV/Approval/Borda/Condorcet voting systems all improve those factors. That they have some edge conditions that could be theoretically exploited belies that fact that plurality voting (ie, FPTP / one person one vote) is a complete train wreck for spoilers and favoring extreme voting.
No voting system is perfect (Arrow's impossibility theorem) but some are harder to exploit than others. Staying with a broken system because the proposed replacement isn't perfect is a poor justification.
I think the problem here is that people get caught up in VSE. I get it, that's what I was caught up in when I first started learning about this stuff. Then I had to really dig through strategic voting and spoilage. The nuance of the systems actually do make a very big difference in the outcomes.
Because for many municipalities, it's not whether they move to Approval vs. RCV or IRV or Star, etc - it's moving away from the dumpster fire of plurality voting.
The non-monotonicity shown there for instant runoff voting seems to be more undesirable than any downsides of approval voting.
IMO the point of elected representation is to be representative, not to elect specific people, so the possibility of a lesser known candidate winning over a major party's favorite candidate isn't a problem.
Arrow's impossibility theorem only says that no _ranked_ voting system is perfect, so it doesn't apply to cardinal methods such as Approval or Score.
> That they have some edge conditions that could be theoretically exploited belies that fact that plurality voting (ie, FPTP / one person one vote) is a complete train wreck for spoilers and favoring extreme voting.
I agree, but I think the nature of the exploitation should still be considered. For IRV, we would be introducing a dependence on unauditable voting machines to tabulate votes, which would make it harder to verify the integrity of future elections.
I tend to not get into this fight because 1) it extends to cardinal systems with Gibbard's and 2) Arrow's is more about social choice than voting.
In a local mayoral election that used IRV, I've seen some candidates tell their supporters to vote for them in every slot. Either those candidates didn't understand IRV themselves, or they didn't want to try to explain IRV to their supporters.
Though with a candidate modification: add 'none of them / no confidence' as a virtual candidate that can never be removed by the runoff processes. If 'NoT' is the winner then the entire election is thrown out and all of the candidates are banned from the re-run.
Computer simulations pretty universally paper over the main problem with approval compared to any ranked-ballot (whether forced or unforced preference) methods by pretending that “approval” has a consistent, cross-voter meaning. (This is an even bigger problem with score-based methods than approval.)
Personally, for simplicity and good enough single winner methods, I prefer Bucklin which is both better than and simpler to explain than IRV, but more critically I prefer minimizing single-winner elections. 5-member legislative districts using a candidate-centric proportional method like STV or the method that has the same relationship to it as Bucklin as to IRV, which AFAIK isn't a named method, would be far superior to any possible system with single-member districts, and basically neutralize districting as a lever for partisan advantage.
Paramount executive elections with a parallel successor (e.g., US Presidential tickets, if they were directly elected, or state Gov/LtGov pairs) can even be made into phased single-winner systems to get some of the advantages of multiwinner systems (not proportionality, but you do get some ability to separate partisan and personal preference in the general election, and to thereby weaken incumbency advantage: basically, use any ranked ballots [0] single winner election for the top spot, eliminate the winner, and rerun the election on the same ballots with the same method for the constitutional successor.)
[0] while I am not partial to them, approval or score systems could be used to; simple FPTP fails because it mean those who voted for the top winner have no voice in the designated successor.
I give an example from this year's Seattle primaries where RCV/IRV would have eliminated the candidate that most accurately reflects the electorate but Approval Voting would not have. That's not a trivial or rare situation, either, it's just such a simple race that it's easy to spot.