[EM] [CES #3845] condorcet & range voting -- which one yields more condorcet winners?

[Jameson Quinn]

2011/10/11 Warren Smith <warren.wds at gmail.com>

> On Tue, Oct 11, 2011 at 8:19 AM, Jameson Quinn <jameson.quinn at gmail.com>
> wrote:
> > Note that the "more Condorcet-like than Condorcet" is only true for Range
> if
> > voters are strategic and somewhat knowledgeable about the polls. It is
> true
> > for Majority Judgment under the same conditions, but also when any
> fraction
> > of voters are honest and ideology is one dimensional; I believe that it
> > holds for N dimensions but I have not proven it. It is true for SODA if
> most
> > voters agree with their candidate's rankings. I believe that these
> > conditions for MJ and SODA are broader than the conditions for Range.
> >
> > Jameson
>
> --But wait -- the simulations in
>
> http://rangevoting.org/StratHonMix.html
>
> found that TopMedianRating returned fewer Condorcet winners than
> average-based range voting.
>

In that sim, Range elected 13279/29999 CWs, and Median elected 12472/29999.
This is a significant difference, but not a huge one. On the other hand are
two effects:
1. Range's greater strategy incentive
2. The tendency for voters to polarize, giving exactly one of the two
frontrunners an *honest* rating near zero. This is a *separate* effect from
strategic exaggeration. If true, this tendency increases the probability
that an honest median vote is strategically strongest, but does not do as
much for Range.


> I believe these sims were conducted with random tie-breaking though
> (not Balinski-Laraki
> nonrandom tiebreak method).
>

I suspect you used enough rating categories (100?) that the difference is
immaterial there.


>
> Maybe you should do sims first, emit flames second.
>

That's a fair criticism, and one I continue to violate in this message. I
wonder if Kevin Venzke has any sims which speak to this question.

Jameson
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