<html><head><style type="text/css"><!-- DIV {margin:0px;} --></style></head><body><div style="font-family:times new roman, new york, times, serif;font-size:12pt"><DIV>Forest,</DIV>
<DIV>You wrote, setting up your attack on IRV:</DIV>
<DIV>"Suppose that the voters are distributed uniformly on a disc with center C, and that they are voting to <BR>choose from among several locations for a community center."</DIV>
<DIV> </DIV>
<DIV>(a) That is quite a big "suppose", and (b) I agree that IRV would not be among the best methods</DIV>
<DIV>to use to vote to choose the location of a community centre.</DIV>
<DIV> </DIV>
<DIV>"The center C of any distribution of voters with central symmetry through C will be a Universal Condorcet <BR>Option for that distribution."</DIV>
<DIV> </DIV>
<DIV>Yes, that is almost a tautology (and to the extent that it isn't it seems to be just a semantic point).<BR></DIV>
<DIV>"And what justification for winning does the IRV winner have?"</DIV>
<DIV> </DIV>
<DIV>I agree that if we suddenly have unfettered access to all the voters' sincere pairwise preferences and that<BR>each voter's different pairwise preferences are all at least approximately as strong as each other, then yes<BR>electing the Condorcet winner is "nicer" and philosophically "more justified" than electing the IRV winner. </DIV>
<DIV> </DIV>
<DIV>However the IRV winner could have as its justification simply the criterion compliances of the IRV method.</DIV>
<DIV>You, as the "election-method salesman", could say to the polity/voters 'customer':</DIV>
<DIV>"This Condorcet method is definitely best for choosing the most central community centre with sincere voting. <BR>I recommend it." </DIV>
<DIV><BR>but they could reply: </DIV>
<DIV>"Does it meet Burial Invulnerability and Later-no-Harm and Later-no-Help as well as Mutual Dominant Third </DIV>
<DIV>and Mutual Majority and Condorcet Loser and Woodall's Plurality criterion and Clone Independence?"</DIV>
<DIV> </DIV>
<DIV>To which you must reply "No", and then the 'customer' says "Then which is the best method that does?", to</DIV>
<DIV>which you reply "IRV" and make the sale.</DIV>
<DIV> </DIV>
<DIV>IRV has some more-or-less unique problems but they are the unavoidable price of a unique set of strengths,<BR>so I don't consider it justified to focus on its problems in isolation. Often this is done, comparing (sometimes</DIV>
<DIV>implicitly) IRV with the best features of several other methods. </DIV>
<DIV><BR>But as you know, I am also supportively interested in Condorcet methods and also Favourite Betrayal </DIV>
<DIV>complying methods such as 3-slot SDC,TR.</DIV>
<DIV> </DIV>
<DIV>Chris Benham<BR></DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV>Forest Simmons wrote (Fri. Dec.5):<BR>Suppose that the voters are distributed uniformly on a disc with center C, and that they are voting to <BR>choose from among several locations for a community center.<BR><BR>Then no matter how many locations on the ballot, if the voters rank them from nearest to furthest, the <BR>location nearest to C will be the Condorcet Option.<BR><BR>Therefore, if C itself is one of the options, it will be the Condorcet Option no matter what the other <BR>options are. So C is more than just a regular run of the mill Condorcet Option, it is a kind of Universal <BR>Condorcet Option for this distribution of voters.<BR><BR>The center C of any distribution of voters with central symmetry through C will be a Universal Condorcet <BR>Option for that distribution.<BR><BR>But no matter how peaked that distribution might be (even like the roof of a Japanese pagoda) the center <BR>C is not immune from the old IRV squeeze
play.<BR><BR>If the good and bad cop team gangs up on C, one on each side, they can reduce C's first choice region <BR>to a narrow band perpendicular to the line connecting the two team mates, thus forcing C out in the first <BR>round of the runoff.<BR><BR>If the team mates are not perfectly coordinated, then instead of a narrow band, C's first choice region <BR>becomes a long narrow pie piece shaped wedge, roughly perpendicular to the line determined by the two <BR>team mates.<BR><BR>This squeeze play can be used against any candidate no matter the shape of the distribution, symmetric <BR>or not. But my point is that even in a sharply peaked unimodal symetrical distribution, the center C, <BR>which is the Universal Condorcet Option, can easily be squeezed out under IRV. And what justification <BR>for winning does the IRV winner have? Merely that it was the closer of the two team mates to the ideal <BR>location C.<BR><BR>Now leaving
the concrete setting of voting for a physical location for a community center, and getting <BR>back to a more abstract political issue space: It doesn't really matter if the good cop and bad cop are <BR>really even anywhere near to opposite sides of a targeted candidate (say a strong third party challenger) <BR>as long as they can make it appear that way.<BR><BR>The two corporate parties are very good at this good cop / bad cop game, especially since the major <BR>media manipulators of public opinion are completely beholden to the giant corporations.<BR><BR></DIV></div><br>
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