[EM] Issues with the Majority Criterion

[Kevin Venzke]

Hi Greg,

--- En date de : Mer 15.10.08, Greg Nisbet <gregory.nisbet at gmail.com> a écrit :
> This is my understanding of the majority criterion:
> If X is supported by >=(floor(.5*number_of_voters)+)
> voters as their first
> choice, then X should win.

What is the meaning of the +?

I would say it is that if X is ranked/rated strictly first by more than
half of the voters, then X should win.

> If the method doesn't satisfy FBC, how can this be
> regarding as a good
> thing, isn't it just making a massive compromising
> incentive?

It is not regarded as a good thing to fail FBC.

I don't understand why you say "massive." Methods vary widely with
respect to how much compromise incentive they provide.

> Does a method count as majoritarian if a majority can
> impose its will, but
> doesn't necessarily have to?

I don't think the term "majoritarian" has an agreed-upon meaning. The way
I define the term, it is not directly related to the majority criterion.

But the term "majoritarian" would be almost meaningless if it meant that a
majority always has some method to make their first preference win.

> Also, how do you define membership in a majority.

It depends on the criterion. For the majority criterion simply, membership
in the majority is determined by you strictly supporting the same first
preference.

> Let's pretend Alice votes Candidate X = 100 Candidate Y
> = 60
> 
> With respect to the majority criterion, does she belong in
> Camp X, or 100%
> in Camp X and 60% in Camp Y?

I don't know any definition of the criterion that doesn't refer to first 
preferences. Even your definition refers to first preferences.

Kevin Venzke