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Re: Range Voting - the simpler better alternative to Condorcet voting

> Ireland uses STV, which is not a Condorcet voting system.

Although true, from a voter's perspective they're pretty much
identical: rank the candidates, any left unranked are implicitly at
the bottom.  Furthermore, I would dare to venture that even our
sophisticated Debian Developer voters by-and-large do not understand
the minutia of our particular Condorcet resolution mechanism.

I will however admit that I've been told by a number of Irishmen that
one reason for the use of STV here is that it makes for a lot of fun
in the post-voting and postmortem parts of the elections.

> Nice try though, it was a very good troll otherwise.

If by "trolling" you mean "pointing out when Steve Langasek makes an
invalid argument", then I plead guilty as charged.

To quote the relevant lines from http://rangevoting.org/vsi.html
where VSI is the Voter Satisfaction Index,

> Voting system                                  VSI A    VSI B
> Magically elect optimum winner                100.00%  100.00%
> Range (honest voters)                          96.71%   94.66%
> Condorcet-LR (honest voters)                   85.19%   85.43%
> Range (strategic exaggerating voters)          78.99%   77.01%
> Condorcet-LR (strategic exaggerating voters)   42.56%   41.31%

> ... These experimental results also strongly suggest that range
> voting is the least susceptible to strategic voting, of these common
> methods.

It would appear that in this table, when voters merely exaggerate
their preferences, which is a natural human tendency, Range Voting
degrades from ~95% VSI to ~78% VSI while Condorcet-LR degrades from
85% to 42%.  OUCH!  It seems like even a small amount of strategic
voting in Condorcet would push its performance below that of Range
voting with fully strategic voting.
Barak A. Pearlmutter
 Hamilton Institute & Dept Comp Sci, NUI Maynooth, Co. Kildare, Ireland

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