The problem with these methods is that you can't afford to vote for the marginal candidate whom only you have heard of, because that candidate will not be part of any S, and so your ballot will count against any S, even an S that you otherwise like.<br>
<br>Jameson<br><br><div class="gmail_quote">2012/1/24 C.Benham <span dir="ltr"><<a href="mailto:cbenhamau@yahoo.com.au">cbenhamau@yahoo.com.au</a>></span><br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
Following on from my recent definition of the APPMM criterion/set, I'd like to propose two not bad 3-slot methods that meet the FBC..<br>
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Recall that I defined the APPMM criterion thus:<br>
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<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
*If the number of ballots on which some set S of candidates is voted strictly above all the candidates outside S is greater than the number of ballots on which any outside-S candidate is voted strictly above any member of S, then the winner must come from S.* <br>
</blockquote>
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The APPMM set is the set of candidates not disqualified by the APPMM criterion.<br>
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APMM//TR:<br>
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* Voters fill out 3-slot ratings ballots. Default rating is Bottom (signifying least preferred and not approved.) The other slots are Top (signifying most preferred) and Middle.<br>
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>From the set of candidates not disqualified by the APPMM criterion, elect the one with the most Top ratings.*<br>
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APMM//CR:<br>
<br>
* Voters fill out 3-slot ratings ballots. Default rating is Bottom (signifying least preferred and not approved.) The other slots are Top (signifying most preferred) and Middle.<br>
<br>
>From the set of candidates not disqualified by the APPMM criterion, elect the one with the highest Top minus Bottom ratings score.*<br>
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So far I can't see that these are technically any better than my earlier suggestion of TTPBA//TR, and unlike that method they fail the "Tied at the Top Pairwise Beats All" criterion.<br>
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But like that method they meet the Plurality and Mono-add-Plump criteria, and also have no problem with Kevin's bad MMPO example.<br>
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I'm happy for APMM//CR to be also called APMM//Range. This method is more Condorcetish than APMM//TR, for example:<br>
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49: C>B<br>
27: A>B<br>
24: B>A<br>
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B>A 73-27, B>C 51-49, A>C 51-49.<br>
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APMM//TR elects A, while APMM//CR elects B (like TTPBA//TR).<br>
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I am sure that APMM//TR has no defection incentive in the "Approval Bad Example", and the other method also does in the example normally given.<br>
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Of course some other points-score scheme (perhaps giving greater weight to to Top Ratings) is possible.<br>
<br>
Chris Benham<br>
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</blockquote></div><br>