RCV isn’t monotonic, meaning that in the right circumstances you can harm your candidate by voting for him. Doesn’t matter how rare it is; what a ridiculous quality for a voting system to have.
I agree it’s a flaw, but the answer isn’t to move to an even worse and more gameable system, it’s to move to proportional systems like MMP.
Cardinal voting systems are terrible because strategic voting is as trivial as it is in FPTP. In IRV situations where strategic voting would be possible exist, but they’re rare and hard to predict. In cardinal systems it’s always best to give the maximum score or the minimum score, and never anything in between.
And when that happens it just defaults to approval, which is still non-monotonic and better than IRV, but it’s been proven anyway that that doesn’t happen and most people are honest (or would learn to be honest after few iterations). IRV is also not devoid of strategy, as it can be better to rank your true favourite lower
IRV is also not devoid of strategy, as it can be better to rank your true favourite lower
I think you missed the part where I said that it can happen, but that it’s rare and hard to predict.
Approval Voting is bad because of the simple fact that it doesn’t let you express any preference. There’s no ability to say “I’ll take this guy if I really have to, to avoid the worst outcome, but if possible I would much prefer this other guy”. In single-winner systems, having some mechanism to express that one candidate is better than another is absolutely crucial.
I think you missed the part where I said that it can happen, but that it’s rare and hard to predict.
Yea, sorry, my wording wasn’t the clearest. I meant to say that it is actually not that rare, and hoped that the linked source would help support that claim. From the same website:
We can [assume that] “all votes [are] equally likely except that the probabilities that A,B,C will be middle-ranked of the three in that vote are 30%, 30%, and 40% respectively” where C is the 3rd-party candidate. Then in IRV as #voters→∞, C’s probability of winning is probably exponentially tiny so that Joe Voter is justified in assuming C only a very tiny […] chance of winning. Indeed C only has a tiny chance of merely surviving the first round. However, Joe reasons, if Joe and friends by honestly-ranking C top do manage to make C survive the first round, then that will almost certainly happen only at the cost of eliminating Joe’s second-favorite candidate A. If the A votes then transfer equally to C and B (which in “1-dimensional politics” with C A B arranged along a “line” in that order, seems likely) then C will almost certainly still lose, and will have deprived A of victory in the process.
The idea then would be that the behavior of mid-ranking the 3rd party candidate would be self-reinforcing in IRV: an assumption of a slight bias that way like we just made (40% versus 30% […]), then leads to it being strategically wise for Joe Voter to do it, leading to a larger bias that way, etc. – positive feedback, self-reinforcing 2-party domination.
Approval Voting is bad because of the simple fact that it doesn’t let you express any preference.
I agree and that’s why I support Score Voting over it! The mechanism to express that one candidate is better than another one is to just give them honest scores! And there’s studies proving that’s the reality is, the vast majority of people are at least somewhat honest when filling out a Score ballot
I think most people would agree that it does matter how rare it is.
Even if imperfect, ranked choice voting would give voters considerably more voice than they have now. That could be used to, for example, vote in another method in the future.
billiam0202@lemmy.world 2 days ago
The point of RCV isn’t to ensure your chosen candidate wins; it’s to ensure that whoever does win has at least some amount of approval from the majority of voters.
It does still have flaws, but it’s still far superior to the current system the US uses.
FrostBlazer@lemm.ee 2 days ago
Really anything other than FPTP is fine. RCV only has the same outcome as FPTP, where the least liked candidate can win, in ~10% of outcomes. Really we should be okay with promoting most of the alternatives since they can be modified down the line as well. I personally promoting Ranked Robin, STAR, and Score more but RCV is always worth supporting if it’s on your local ballot vs FPTP. Most people are just more familiar with RCV if they have heard of some of these alternatives.