[EM] Condorcet divisor method proportional representation

[Kathy Dopp]

On Sun, Jul 3, 2011 at 2:33 AM, Kristofer Munsterhjelm
<km_elmet at lavabit.com> wrote:
> Kathy Dopp wrote:
>>
>> I do not like this system and believe it is improper to call it
>> "Condorcet". It seems to have all the same flaws as IRV - hiding the
>> lower choice votes of voters, except if the voter voted for some of
>> the less popular candidates.  Thus, I can see there may be lots of
>> cases when it eliminates the Condorcet winner.
>
> Do you mean that it fails to elect the Condorcet winner in some singlewinner
> elections, or in multiwinner ones? If it's the latter, then there's a
> perfectly good reason for that.
>
> Let me pull an old example again:
>
> 45: Left > Center > Right
> 45: Right > Center > Left
> 10: Center > Right > Left
>
> If there's one seat, Center is the CW; but if you want to elect two, it
> seems most fair to elect Left and Right. If Center is elected, the wing
> corresponding to the other winning candidate will have greater power.

I disagree. In your example, clearly 55 prefer right to left, but only
45 prefer left to right.  And center is the clear winner overall.
Thus, if only two will be elected, it should be center and right.
Unless you really like hung partisan governments run by opposite
extremists who care more about the next campaign than about governing
- like we have now in the US Congress.  Any method that reduces to
IRV, like STV does, is going to tend to elect extremists rather than
majority preferred centrists, and thus contribute to bad governing
practices IMO.

So, I say that the word "Condorcet" applied to that method is wrong.
At least in the case of multi-winner elections -- as your example
shows.



-- 

Kathy Dopp
http://electionmathematics.org
Town of Colonie, NY 12304
"One of the best ways to keep any conversation civil is to support the
discussion with true facts."

Fundamentals of Verifiable Elections
http://kathydopp.com/wordpress/?p=174

View some of my research on my SSRN Author page:
http://ssrn.com/author=1451051