[EM] Strategy-free criterion

[Kevin Venzke]

Hi Chris,

Chris Benham <cbenhamau at yahoo.com.au> a écrit :
> > What I call inherently of value would be things like sincere Condorcet efficiency or
> > reduced strategic incentives.
> 
> I can understand voted Smith-set fundamentalism, and that is expensive enough. But if
> there is a top cycle I don't share the mind-set "Probably there is a sincere CW
> (concealed by strategic truncation or order-reversal) and our top priority should be to
> infer or guess who that is and elect him/her."  There may well be no sincere CW or a
> higher SU candidate. So quite nice, but mainly just a marketing benefit.

I'm not sure how to read this. If I could prove that method XYZ was the best at
sincere Condorcet efficiency (or substitute SU if you prefer), you would categorize
that as mainly a marketing benefit? To me this is the entire thing that the method
is supposed to be doing.

> https://electowiki.org/wiki/Strategy-free_criterion
> 
> If a Condorcet candidate exists, and if a majority prefers this candidate to another
> candidate, then the other candidate should not win if that majority votes sincerely and
> no other voter falsifies any preferences.
> 
> I think that is very similar to the Generalised Majority Criterion,

It's much more limited.

> enough for me to
> reject it on the same grounds. And even if I didn't have that criticism, I don't see
> why it's something we should care much about. It looks like something contrived just to
> serve as ammunition against Hare and Margins.

It does have that role, but Hare/Margins already fail the other criteria. I have
always viewed SFC as an explanation of what could be improved in Approval.

I would not say someone needs to care about SFC specifically, but it addresses
truncation incentive, so it isn't useless to satisfy it.

> (And possibly the similar GMC was contrived just to help promote the Schulze method.)

If one thinks GMC was contrived just to support Schulze(WV), it's worth asking how
Woodall also managed to invent it (as CDTT).

> I would think that if the method
> is making some attempt to minimise the number of "wasted votes", then
> many voters would want to be able to express their full sincere ranking
> and also would at least not mind giving their sincere or semi-sincere
> approval cutoff.

I have nothing against explicit cutoffs.

Kevin
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