Two-level MJ is approval, because of the tiebreaker. Example: Say A gets 52% approval and B gets 57%. Both will have a median of "approved". After removing 4% "approved" votes from each, A's median will drop to "unapproved", and B will win.
So if probabilistic SFR works in approval, it works in two-level MJ. And it also works in pure-100%-strategic MJ. And also for a divided majority, it works to use probabilistic SFR using grades of min and min+1. Until you understand that, this discussion is going nowhere. Also, the first time in this thread that I said CMJ, I linked to the electowiki page which describes it. As I've told you to do many times. Here's the link again: http://wiki.electorama.com/wiki/index.php?title=CMJ If you continue to insist on the same points, without actually listening, I won't respond. 2012/9/7 Michael Ossipoff <[email protected]> > I'd said: > > >> ...and it [SFR] isn't available in MJ, for the reasons that I described > in > >> my previous reply to you. > > > Jameson replied: > > > Yes it is. Because with approval-style votes, MJ gives approval results. > > No. Not with a different count-rule. > > I'm just guessing, but you seem to want to say that, though > Score-style SFR won't work in MJ, Approval-style probabilistic SFR > will work. Ok, let's look at what would happen: > > Suppose that you want to do probabilistic SFR in MJ. You want to > probabilistically give N points to candidate X. So, with a probability > of N/max, you give X max points instead of 0 points, as you would in > Approval, to probabilistically give N points to X. > > What will be the result?: > > Depending on what N/max is, and depending on the sizes of the > factions, on on how other factions vote, X's MJ score might be 0, or > max, or some inbetween amount that you and your faction have _no_ > influence on. > > In other words, probabilistic SFR doesn't work in MJ, just as > Score-style SFR doesn't work in MJ (as I showed in previous postings) > > Jameson, you really need to better say what you mean. You need to > better specify whatever strategy it is that you want to suggest for > MJ, in order to achieve SFR. > > I've told you why Score-style SFR won't work in MJ, and I've just now > told you why Approval-style probabilistic SFR won't work in MJ. If > there's some other strategy that you think can achieve SFR in MJ, then > you need to actually specify it. And then, don't forget to furnish an > example to show that your strategy works, and how it works. > > > > if it's possible under approval, it is possible under MJ. > > Certainly not. MJ isn't counted as Approval is counted. I've just told > you what would happen if you attempted Approval-style probabilistic > SFR in MJ. > > > And in scenarios like the one you gave, where the median of the unified > > minority candidate (C) is known (0 in your case) > > Sure, C is known to have a median of 0, provided that A voters and B > voters add up to a majority, and 0-rate C. > > > , it doesn't require votes > > of max or min; it can be done just as well with votes of min or min+1 > > ...in order for A voters to help B to beat C. Certainly. The problem > is that if the B voters don't reciprocate, and give 0 to A, then B > will win by defection. > > > >> SFR could be done unilaterally, or could be done by agreement--an > >> agreement that doesn't depend on trust, but only on the other > >> faction's self-interest. > >> > > > > As in MJ. > > No. I've told why Score-style SFR, and Approval-style probabilistic > SFR, won't work in MJ. > > You can't have MJ with Score properties. You have to choose between MJ > and Score. > > >> Several people at EM have discussed and demonstrated why Approval soon > >> homes in on the voter median, and then stays there. > > > > > > Did you even read that page? Because that's a non-sequitor response to > that > > page, as far as I can tell. You're just repeating prior assertions. > > You'd said something to the effect that median does well, or the > median does well. I assumed that you meant that the median candidate > does well in Approval and Score. But apparently you were temporarily > changing MJ's name to "median". Ok, that's fine. > > So you're saying that a more sophisticated discussion at a website > shows that MJ does well, whatever that means. > > That's nice, but I've shown here that MJ doesn't do SFR at all. > > How regrettable that you're unable to quote those highly sophisticated > arguments here, from that website. So then, you're saying that that > website's more sophisticated arguments show that MJ can do SFR? Or, if > that isn't what you mean, then do you want to tell us what you mean? > If you don't want to, that's ok. > > Yes, by all means, if you want to, do quote for us those more > sophisticated arguments that show that SFR can be done in MJ, or that > the Chicken Dilemma is less serious with MJ. > > But "handwaving" at a website just won't do. > > ...a vague statement that some website's sophisticated arguments show > that MJ does well, whatever that means. > > > > >> > >> In fairly recent postings, I've told some reasons why the Chicken > >> Dilemma won't be as much of a problem when looked at over time (as > >> opposed to in one single particular election) in Approval or Score. > >> But sometimes one wants to avoid the Chicken Dilemma in one particular > >> election. That's when SFR is more important. But it's helpful in > >> general too--and unavailable for MJ. > > > > > > Wrong. > > So you've claimed. I've told why Score-style SFR won't work in MJ. > And, in this post, I've told why Approval-style probabilistic SFR > won't work in MJ. > > >> > In practice, in MJ both factions could rate each other's candidate at > 1 > >> > (the > >> > second-from-bottom rating). This would mean that any further defection > >> > would > >> > be risky > >> > >> No it wouldn't. If the A voters rate B at 1 (out of 100), and the B > >> voters rate A at 0, then here are the MJ scores: > >> > >> A: 0 > >> B: 1 > >> C: 0 > >> > >> (...for the reasons described in the post before this one, the post > >> that you're replying to) > >> > >> B wins by defection. > > > > > > This defection is dangerous: if both sides do it, C wins. > > Exactly. That's a necessary condition to have a Chicken Dilemma. > Because bilateral defection is so dangerous, the A voters, being more > co-operative, feel compelled to not defect. And that's why they're had > by the B voters. > > > And it is not a > > temptation as with score or approval: unlike score or approval, it is > > impossible for defection short of that required to give C a chance, to > give > > A or B an advantage. > > You need to re-word that, to better say what you mean (provided that > you mean something and know what you mean). > > Of course defection by B "gives C a chance" if the A and B factions > both defect. That's why there's a Chicken Dilemma. That's equally true > in MJ, as you yourself agreed in some abovequoted text. > > >> Sure, if the A voters and the B voters both give eachother's candidate > >> a point, then the winner will be A or B. But that just means that > >> there isn't a problem if no one defects. The Chicken Dilemma is about > >> what happens when someone _does_ defect. > > > > > > Yes. When some ONE. Not when some entire faction, as in your example. > > It's customary, when speaking about such problems as the Chicken > Dilemma, to speak of there being two "players". That doesn't mean that > there are only two voters in the election. It means that the A and B > factions are each collectively referred to as a "player". That's a > convenient simplification. > > Are you saying that, in a large election, MJ doesn't have a defection > problem if only one voter defects? > > > You don't understand MJ or CMJ. > > I have no idea what CMJ is. I've been talking only about MJ, because > it's a popular proposal. > > > > They both have "tiebreaking" procedures that > > would naturally give the right result. > > Of course. MJ needs that. Do you remember when I said that MJ has > elaborate bylaws? > > >> For one thing, tie-proneness isn't > >> considered a good property. > > > > > > In CMJ, the "tiebreaker" is an integral part of the process, such that > the > > tie is broken before it even exists. There is no sense in which CMJ can > be > > called tie-prone. > > Again, I have no idea what CMJ is. But of course, it goes without > saying that when the needed tiebreakers are added to a tie-prone > method, then it can be called "not tie-prone". > > When MJ gives the same median score to two candidates, as in the > example I discussed, and if you wouldn't flip a coin--you forgot to > tell us what you'd do instead. But it doesn't matter. It comes under > the term "elaborate bylaws". > > >> For another thing, A's win probability > >> will be 1/2, even if A has many more voters than B has. > > > > > > Wrong. > > Jameson, when you say, "Wrong", you should then tell why it's wrong :-) > > Ok, if, in the situation that I described, where the A and B factions > both rated eachother's candidate at 1, and they both ended up with > equal MJ scores: If you wouldn't flip a coin to choose between those > two equal-MJ-score candidates, how would you choose between them? In > MJ. We're talking about MJ, as it's popularly proposed, not CMJ, > whatever that is. > > >> If you want to talk about co-operative trust (as you were doing), > >> then, in Score, each faction could agree too trustingly and ethically > >> give eachother's candidate max minus one. Then, they're helping > >> eachother nearly maximally against C, and yet whichever of {A,B} has > >> more voters will be the winner. > >> > >> That's another thing that won't work in MJ. > > > > > > Um, yes it will. > > Um, if both the A and B factions give the same non-0, non-max, rating > to eachother's candidate, and if neither A nor B has a majority voting > it 0 or max, and if the C voters give 0 to A and B, then A and B will > both have the same MJ score. For reasons that I've already told. > > In other words, even if the A faction is larger than the B faction, A > and B will still have the same MJ score. In other words, the > co-operative strategy that I described doesn't work in MJ. > > Um? > > Mike Ossipoff >
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