[EM] IRV vs Plurality

[Abd ul-Rahman Lomax]

At 08:10 PM 1/26/2010, Juho wrote:

>The scenario that you described requires some goodwill among the
>voters.

That's correct. We seem to imagine that better voting systems will 
produce better results even if people continue to lack goodwill and 
cooperative spirit. It's a fantasy. There are structural changes that 
will encourage the seeking of consensus, but voting methods are only 
a tiny part of that.

>  If the competition is really strong then one could expect the
>70% of the voters not to even mention the 99% approved candidate in
>the polls if they already know that they have 70% majority behind
>their first preference.

That's right, if they don't care about alienating 30% of the members 
of the organization, an organization that breaks down and becomes 
dysfunctional if people fight with each other and fail to respect the 
need for unity.

>On the other hand the availability of reliable poll information may
>reduce the competitive spirit of the election.

What you do is to poll, and allowing approval polling is simple, 
nobody even though of suggesting that people only vote once in the 
show of hands. The question wasn't a preference question, it was 
"would you consider this choice acceptable." The poll wasn't going to 
decide anything, and this was a group of people whose culture 
facilitated and encouraged complete honesty, and the whole thing 
would become a stupid waste of time without the honesty, it was 
fundamental and crucial, or even more than a stupid waste of time, 
positively harmful.

>  Some part of strategic
>voting and strong competitiveness is based on the fear of unknown and
>lack of understanding of the viewpoints of the others. If all take a
>defensive attitude from the start and paint all their competitors with
>dark colours then there may never be any consensus.

Right.

>  In typical
>political environments good poll information including approvals and
>ratings is thus a positive thing, but it may still be necessary to
>assume that strong competition is not uncommon in the actual election
>and prepare for that.

Yes. I do suggest Bucklin. Most voters will bullet vote, it's very 
likely, but, then, use it as a primary in a runoff system, which 
provides a very specific meaning to the lowest approved rank: I 
prefer the election of this candidate to holding a runoff. It's an 
absolute, sincere vote that is strategically maximal! Because that is 
exactly the effect it has, monotonically.

>Voters may also understand that a society that makes consensus
>decisions may be a better place to live in than a society where the
>current majority always ignores the minorities. And people may vote
>for parties that support this approach. But also here, it may still be
>wise to allow the majority to decide when consensus decisions (that
>cover also the needs of the other side) will be made. In a way we are
>talking about a "benevolent majority" and the growth of a society
>towards away from a conflict driven mode.

Majority rule is a crucial foundation for democracy. But if the 
majority is stupid, it can wreck the place, and everyone is in the 
minority from time to time. Seeking supermajority approval actually 
helps everyone, long-term, but there is a tradeoff with efficiency.

>Yes, the good part of Range is in the satisfaction measurements. I
>think the strategy problems are very real in many environments, not
>just hot air. So one must be careful with Range.

The typical error is in assuming some "strategic" faction which votes 
sensibly, when everyone else votes in a way that they will regret if 
they discover the result they cause.

[...]
>There is a natural incentive to the two largest groupings to promote
>this kind of polarization. And a two-party system is a demonstration
>that such systems may also work reasonably well in practice.

Sometimes, when the social contract is strong and the distance 
between the two parties is actually not large (i.e., Tweedledum and 
Tweedledee might be a bit of a good thing!), it works, but sometimes 
it leads to civil war and genocide, when the polarization becomes too great....