[EM] Strategy-free criterion

[Kevin Venzke]

Corrections:

> Kevin Venzke <stepjak at yahoo.fr> a écrit :
> Hi Chris,
> 
> Chris Benham <cbenhamau at yahoo.com.au> a écrit :
> > >  The disunited majority has three options to avoid the [Chicken Dilemma] criterion's wrath:
> > >
> > > 1. The "defecting" faction can add another preference, if they have it or are
> > > willing to lie that they have it.
> > >
> > > 2. The "defected-against" faction can compromise and try to give the other
> > > candidate a majority of first preferences.
> > >
> > > 3. One of the candidates can simply drop out of the race, as it will be apparent
> > > that the method poses such risks.
> > >
> > 
> > You said that you thought one of these is positive. Which one?
> > 
> > I am still thinking about a much  fuller reply.
> 
> #1 includes a truncation disincentive so I'm willing to call it positive. You could
> also see a random-fill incentive there I suppose. And when a voter deliberately
> gives a specific lower preference that they don't actually have, we usually call
> that burial... A kind of "defensive burial" in this case.

Actually, given how CD is actually defined (and not how I might define it),
characterizing this as random-fill or burial is wrong, because voters adding an
additional preference are conceding the election to that preference. It's not
too plausible that their preferred candidate will actually win.

So, #1 is indeed positive and has nothing to do with lying.

The caveat of course is that if the voters targeted by incentive #1 actually don't
have a second preference, then CD imposes a sub-optimal MD-defying outcome for no
benefit at all.

Kevin
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