[EM] Participation

[Kristofer Munsterhjelm]

Abd ul-Rahman Lomax wrote:
> At 11:57 PM 4/24/2010, Kevin Venzke wrote:
>> Hi Abd,
>>
>> --- En date de : Sam 24.4.10, Abd ul-Rahman Lomax 
>> <abd at lomaxdesign.com> a écrit :
>> > This is what is common with the
>> > use of voting systems criteria to study methods. Scenarios
>> > are created, sometimes cleverly, to cause a failure of a
>> > criterion. Does it matter if those conditions never exist?
>> > It should.
>>
>> For the simple question of whether the criterion is satisfied or failed,
>> no it doesn't. Of course people then do go on to disagree about whether
>> certain criteria are important, and why. There is nobody who thinks every
>> single criterion is important.
> 
> That's right. But until utility analysis started to be done, the 
> arguments had practically no foundation, they were just ideas about what 
> democracy should look like, sometimes intuitions, and sometimes quite 
> deceptive. Some criteria may be positively harmful, and Later No Harm is 
> one of those. No method that maximizes utility can satisfy Later No 
> Harm, no method that finds the best compromise winner can satisfy it.
> 
> And no method that maximizes social utility, overall satisfaction, can 
> satisfy the majority or condorcet criteria, as fundamental as they seem, 
> when only a single ballot is used. They can by using a second ballot to 
> ratify (or reverse) an original election that finds the utility maximizer.

To me it seems that wouldn't be the case either. Consider the case of a 
top-two runoff (with Range as the first round) where the two winners are 
both supported by a minority. Then no matter who wins the runoff, the 
method as a whole has failed the Majority (and Condorcet) criterion.

Unlikely? Perhaps, but one failure is enough. Of course, you could then 
argue on basis of social utility (as you have), but you can't say the 
method passes the criteria.

One could also formulate criteria based on score, for instance: "if a 
candidate X is given more than half the points given by voters in that 
election in total, he should win" - a score/Range version of Majority.