[EM] Weak Condorcet winners [was: FairVote are not the friendliest]

[Juho Laatu]

Many people on this list agree that Condorcet methods are good methods. But they are not necessarily good for whatever needs. Using them in single-seat districts of a two-party system might not be a good idea. We might end up having majority of the representatives from a small centrist party. When we discuss about which method is best we should always also understand for what kind of election and for what needs they are proposed. There is no single "utility order" of election methods.

I guess now we are talking about Condorcet methods in an environment with strong two-party traditions. Let's assume that the two-party system is intentional. I.e. we want the system to be a two-party system. A good solution to fixing the problems of FPTP (e.g. the spoiler problem) would be to ban all other candidates except the two candidates of the two parties. That would be a perfect solution.

Maybe that is too radical though. Maybe many two-party systems would like third parties to have a chance. Maybe there should be a possibility of one new party growing and replacing one of the old two parties. In such an environment we might have a requirement to pick the winner from the two largest groupings (maybe separately in each single-winner district). TTR/TRR could be a natural choice here. Third parties could make their way to the second round only if they have become more popular than one of the old two parties.

Maybe one wants to offer a chance also to independent candidates that happen to be popular. The solutions of the previous paragraph could work here too.

One possible target could be to allow several candidates from both two major parties to participate in order to allow the voters to pick their favourite from a wider choice of candidates. Preliminaries are one approach to solve this problem (possible spoiler effect). One could also have methods that can pick the best candidate at one round (without spoiler, without allowing small third parties to win). One could either allow supporters of all parties to decide which candidate of the strongest party will win, or alternatively supporters of the strongest party could have more say on which one of their candidates should be chosen.

The targets and recommended methods, and maybe the whole structure of the election (e.g. single-seat districts vs. proportional multi-seat districts) could be different. Also in such environments Condorcet methods might not be relevant. Or maybe they would be relevant in presidential and other clear single-winner elections. Picking a weak Condorcet winner might not be a problem any more but a good target.

In a situation where one wants to move from a two-party system towards a multi-party system the old way of thinking might be important. People might feel that a weak Condorcet winner must be a weak elected official since he will not have support from any strong group. That could of course be a temporary problem that will vanish after people have learned how to live with numerous large and small parties.

In the discussion above Condorcet methods appeared to be pretty useless methods. Of course they are not useless in general. But my point is that if one wants to propose improvements e.g. for election methods used in a two-party country, one should clearly point out (or agree) what the needs are or what the end result should be like before one can make solid claims on which methods meet the requirements best. General claims that X is better that FPTP should have also an explanation part "for what needs".

Use of Condorcet could make a well working two-party system worse (depends on what one wants). But it could be a perfect solution for some other needs.

Juho



On 22.9.2011, at 19.40, James Gilmour wrote:

> Jameson Quinn  > Sent: Thursday, September 22, 2011 2:00 AM
>> If I'm right, the claim is that voters, and especially 
>> politicians, are intuitively concerned with the possibility 
>> of someone winning with broad but shallow support. In 
>> Approval, Condorcet, Majority Judgment, or Range, a 
>> relatively-unknown centrist could theoretically win a contest 
>> against two high-profile ideologically-opposed candidates. 
>> The theory is that the electorate would be so polarized that 
>> everyone would explicitly prefer the centrist to the other 
>> extreme, but because the voters don't really expect the 
>> low-profile centrist to win, they might miss some important 
>> flaw in the centrist which actually makes her a poor winner.
> 
> I cannot comment on the quoted remark (cut) that prompted your post and I know nothing at all about the activities of anyone at
> FairVote, but you have hit on a real problem in practical politics in your comment above  -  the problem of the weak Condorcet
> winner.  This is a very real political problem, in terms of selling the voting system to partisan politicians (who are opposed to
> any reform) and to a sceptical public.
> 
> For example, with 3 candidates and 100 voters (ignoring irritant preferences) we could have:	
> 	35 A>C
> 	34 B>C
> 	31 C	
> "C" is the Condorcet winner.  Despite the inevitable howls from FPTP supporters, I think we could sell such an outcome to the
> electors.
> 
> But suppose the votes had been (again ignoring irrelevant preferences):
> 	48 A>C
> 	47 B>C
> 	 5 C	
> "C" is still the Condorcet winner - no question about that.  But I doubt whether anyone could successfully sell such a result to the
> electorate, at least, not here in the UK.
> 
> And I have severe doubts about how effective such a winner could be in office. Quite apart from the sceptical electorate, the
> politicians of Party A and of Party B would be hounding such an office-holder daily.  And the media would be no help  -  they would
> just pour fuel on the flames.  The result would be political chaos and totally ineffective government.
> 
> The flaw in IRV is that it can, sometimes, fail to elect the Condorcet winner.  But IRV avoids the "political" problem of the weak
> Condorcet winner.  I suspect that's why IRV has been accepted for many public and semi-public elections despite the Condorcet flaw.
> 
> James Gilmour
> 
> 
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