[EM] Majority-Judgement. Condorcet.

[MIKE OSSIPOFF]

MJ:

Thanks for all the answers about MJ strategy.

But I'd told how easily a strategic faction can take advantage of and beat a sincere-voting faction.

And, if the contest is close, then even a small difference in sincerity could decide which faction's candidate wins.

And that amounts to a co-operatioin/defection problem too.

No amount of speculation or discussion of MJ's other strategy issues or mystique will make that go away.

Thanks, Kristofer, for confirming my conjecture: MJ strategy is like RV strategy.

This is for sure: In a u/a election, MJ's strategy is the same as that of RV: Max-rate the acceptables and
min-rate the unacceptables.

I conjecture that, in a non-u/a, 0-info election, MJ's strategy is likewise identical to that of RV: Max-rate the
above-mean candidates and min-rate the below-mean candidates.

I further conjecture that all MJ strategy, u/a and non-u/a, 0-info and not 0-info, is the same as that of RV:

Max-rate all of the candidates whose merit, for you, is above your expectation for the election. Min-rate all of 
the candidates whose merit, for you, is below your expectation for the election.

Of course many Approval strategies have been discussed at EM, but they all are instances, special cases, of the
above-stated better-than-expectation strategy.

Condorcet:

Condorcet is almost fine if you don't care about FBC or the co-operation/defection problem.

I've already told why I consider FBC and CD to be important. There's no need to repeat that now.

I've been saying that, when advocating a criterion, one should say why one considers it important. I've amply done
that, regarding FBC and CD.

So, if you advocate Condorcet, it's because we agree to disagree about FBC and CD.

Above, I said "almost fine". That's because, even aside from FBC and CD, Condorcet doesn't work as well as I'd 
formerly believed. My claims about Condorcet's powerful thwarting and deterence of burial strategy were all based on
3-candidate examples.

Just as we all have been in denial about the co-operation/defection problem, maybe I and some others hadn't wanted
to look at what can happen when there are more than 3 candidates in Condorcet.

Condorcet's thwarting and deterence of burial, it seems to me, doesn't work nearly as well when there are more
than 3 candidates. That means that SFC doesn't mean as much. SFC was central to my advocacy of Condorcet.

So, for all of those reasons, I don't consider Condorcet, in any of its versions, to be a good proposal for single-winner reform.

In addition to Approval's FBC compliance, and the fact that CD compliance can easily be added via the conditional
options, Approval is the answer to the question "There are so many voting system proposals--Why should we choose
yours?". 

Approval's answer is:

"Because Approval is the minimal, obvious, natural, easily-implemented, improvement-change from Plurality. Plurality done right. Approval
transparently eliminates Plurality's worst problem, without adding one."

And then, with the conditionality-options added, perhaps in a later proposal, the method will have un-equalled
freedom from strategy problems, unmatched mild strategy.

Could it be that the simplest and most obvious and natural is the also best, in terms of getting rid of strategy problems? 

Yes.

Mike Ossipoff



 		 	   		  
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