[EM] Historical perspective about FairVote organization

[Richard Fobes]

On 3/15/2013 2:12 AM, Kristofer Munsterhjelm wrote:
> On 03/14/2013 06:45 PM, robert bristow-johnson wrote:
>> IRV will prevent a true spoiler (that is a candidate
>> with no viable chance of winning, but whose presence in the race changes
>> who the winner is) from spoiling the election, but if the "spoiler" and
>> the two leaders are all roughly equal going into the election, IRV can
>> fail and *has* failed (and Burlington 2009 is that example).
>
> If you think about it, even Plurality is immune to spoilers... if the
> spoilers are small enough. More specifically, if the "spoilers" have
> less support in total than the difference in support between party
> number one and two, Plurality is immune to them.
>
> So instead of saying method X resists spoilers and Y doesn't, it seems
> better to say that X resists larger spoilers than Y. And that raises the
> question of how much spoiler-resistance you need. Plurality's result is
> independent of very small spoilers. IRV's is of somewhat larger
> spoilers, and Condorcet larger still (through mutual majority or
> independence of Smith-dominated alternatives, depending on the method).

This is a good example of the need to _quantify_ the failure rate for 
each election method for each "fairness" criteria.

Just a yes-or-no checkmark -- which is the approach in the comparison 
table in the Wikipedia "Voting systems" article -- is not sufficient for 
a full comparison.

...

> It's like reinforcing a bridge that would collapse when a cat walks
> across it, so that it no longer does so, but it still collapses when a
> person walks across it. Cat resistance is not enough :-)

Great analogy.  We need to start assessing _how_ _resistant_ each method 
is to each "fairness" criteria.

> It would be really useful to know what level of resistance is enough,
> but that data is going to be hard to gather.[...]

Indeed, that is difficult.

 > And beyond that we have even harder questions of how much resistance
 > is needed to get a democratic system that works well. It seems
 > reasonable to me that advanced Condorcet will do, but praxeology
 > can only go so far. If only we had actual experimental data!

My VoteFair site collects lots of data.  I have used it to verify that 
VoteFair ranking accomplishes what it was designed to do.  Not only has 
such testing been useful for refining the code for the single-winner 
portion (VoteFair popularity ranking, which is equivalent to the 
Condorcet-Kemeny method), but such testing has revealed that VoteFair 
representation ranking (which can be thought of as a two-seats-at-a-time 
PR method) also works as intended.

As for praxeology ("the study of human conduct"), I also watch to see 
how people try to vote strategically.  The attempts are interesting, but 
ineffective.

I agree that using better ballots and better vote-counting methods in 
real situation -- using real data -- is essential for making real progress.

Richard Fobes