[EM] Winning-votes intuitive?

[Rob LeGrand]

Adam wrote:
> 49: Bush
> 24: Gore
> 27: Nader,Gore
>
> Bush beats Nader 49-27
> Nader beats Gore 27-24
> Gore beats Bush 51-49
>
> With ranked pairs, the Gore-Bush defeat is overturned, and Bush wins,
> despite a true majority preferring Gore to Bush.  In SSD the Nader-Gore
> defeat gets overturned, and Gore wins, which seems more intuitive to me.

I think the reason the winning-votes method seems more intuitive in this case
is that, looking at the votes, there seem to be 49 Bush voters and 51
Gore/Nader voters, so a Bush result seems wrong.  But that's misleading.  The
24 Gore voters don't prefer Nader to Bush.  If they had voted Gore>Nader>Bush,
then I'd agree that Bush should lose.  But, if you ask me, the above election
is more accurately expressed as

49:Bush>Gore=Nader
24:Gore>Bush=Nader
27:Nader>Gore>Bush

which should be equivalent to

49:Bush>Gore>Nader
49:Bush>Nader>Gore
24:Gore>Bush>Nader
24:Gore>Nader>Bush
54:Nader>Gore>Bush

Now Bush wins using Schulze and Ranked Pairs, not to mention Borda, Dodgson,
Nanson and Minmax.  I'm not a winning-votes fan, and this has been a hotly
debated topic on the list in the past, so there are several who won't find my
reasoning convincing.  But if I were one of the Nader voters (*shudder*) and a
winning-votes method were being used, I'd vote Nader=Gore>Bush.  Winning-votes
methods may discourage truncation, which is nothing more then tied rankings at
the bottom, but they strongly encourage tied rankings at the top.  In fact, I'd
vote ties in the top half or so of my ballot, even if I had *zero* information
about the other voters' preferences!  "Margins" methods don't encourage tied
rankings like that on average, although of course there will be situations that
reward insincere voting in any method.  I don't think of using margins at all,
though; to me a tie in a ballot should simply result in half a pairwise vote
each way.  That's the way I do it in my online ranked-ballot voting calculator
at http://www.onr.com/user/honky98/calc.html .  Has anyone tried it out?  It's
not completely finished yet, but I'd love some feedback (preferably private, of
course).


=====
Rob LeGrand
honky98 at aggies.org
http://www.aggies.org/honky98/

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