[EM] Proportional multi-winner ranked voting methods - guidelines?

VoteFair electionmethods at votefair.org
Sun Feb 26 21:44:38 PST 2017

On 2/23/2017 12:08 PM, Toby Pereira wrote:
> Does the VoteFair method obey a specific proportionality property? For
> example, if you insist on electing the Condorcet winner, this is
> incompatible with Droop proportionality - e.g.
> https://groups.google.com/forum/#!topic/electionscience/n__VhVgjJqg

In VoteFair ranking, the first seat in a district is won by the winner 
according to the Condorcet-Kemeny method.  The winner of the second seat 
in the same district is determined by first proportionally reducing the 
influence of the voters who are already well-represented by the first 
winner, and then with the remaining preferences, calculating the 
Condorcet-Kemeny winner.

So, yes, those results are Condorcet compliant.  Obviously those results 
alone do not assure proportional results.

For the proportional part of the results, some "nationwide" seats in 
parliament (or the legislature) are reserved for proportionality 
adjustments.  The criteria for winning them is not mathematically 
sophisticated (because it involves comparing the popularity of 
candidates who were not in the same race), so I doubt that the result 
meets any sophisticated proportionality criterion.  And I doubt that the 
results meet Droop proportionality because that calculation method is 
quite different.

With VoteFair ranking, a greater number of nationwide seats increases 
proportionality, but that reduces the number of seats filled by the 
carefully selected -- Condorcet-compliant -- district-based winners. 
It's a balance that needs to be adjusted according to the needs of the 
nation using it.

As a clarification, VoteFair ranking does not attempt to achieve fully 
proportional results for every political party.

Instead it attempts to ensure that the majority of elected MPs (members 
of parliament) best represent the majority of voters, keeping in mind 
that political parties are often not really representative of voters.

This concept relates to what's currently going on in U.S. politics. 
Most U.S. voters are not well-represented by either the Republican party 
or the Democratic party.  In particular, if fair methods of voting were 
used here, none of the candidates who were in the primary elections 
would have won those primary elections.

Expressed another way, voters want problem-solving leaders, but unfair 
election methods give us special-interest puppets.

Richard Fobes

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