[EM] Majority Criterion poor standard for elections

[Abd ul-Rahman Lomax]

At 04:36 PM 10/26/2006, Juho wrote:
>On Oct 26, 2006, at 5:21 , Abd ul-Rahman Lomax wrote:
>>>I at least made a try few mails back on the list with "Ranked
>>>Preferences".
>>
>>Tried what? To satisfy the Majority Criterion while allowing
>>preference strength to influence the outcome?
>
>Yes.
>
>>I don't think it is possible.
>
>I think it is. Not in the Range style but maybe if one treats the
>strength of preferences in a different way (and doesn't allow them to
>influence in "wrong" places).

Well, there is one way that it could happen. If there is no candidate 
such that the Majority Criterion applies, then *of course* it is 
possible to use preference strength to choose between non-majority 
preferred candidates.

But the whole point of my argument has been that the Majority 
Criterion, when it *does* apply, can easily require the selection of 
a candidate who is, clearly, suboptimal or even quite harmful. It is 
true that if there is sufficient public deliberation, this is 
unlikely, which is why election methods such as plurality work as 
well as they do. They work in spite of their potential defects. But 
those defects can, as various forces shift the balance of power, lead 
to a disastrous outcome. Media domination, for example, can lead to 
defective deliberative process, the public debate that properly 
precedes elections.

>>However, I found the description of "Ranked Preferences" to be
>>incomprehensible. It's *complicated*.
>
>I agree that it is complicated. Please point out if there are some
>specific details that I didn't explain properly.

I did not get the idea. At all. Sorry, it seemed to me that the 
algorithm was not explained, but if it was, it was without the kind 
of overall description that makes it easy to understand.

>  The overall
>complexity can not be helped (except by dropping some of the rules
>like tied at top). Better description styles could be possible.
>
>>I suspect that there might be a way of expressing it which is much
>>simpler, or maybe not. If not, forget about it. If I can't figure
>>it out with a few minutes of focused attention, the public will
>>*never* go for it.
>
>I agree that most of the public will not bother to dive inside the
>voting method to see how it works.

I'm not going to trust an election method that I don't at least think 
I understand.

>  That is the same for many voting
>methods. They may however trust if the experts say that the method
>works ok.

Maybe. But getting that consensus of the experts.... not at all easy.

>  The voting process is however relatively simple and
>understandable. Just put the candidates (or the best of them) in
>preference order and add strengths to the preferences if you feel
>like that (basic (flat preference) ranked votes work also fine).

Same is true of Range, a method easy to understand. People *are* 
familiar with it. (except for weirdnesses like the 25% rule, if that applies).


>>>Votes 55: A>B>>C, 45: B>>A>C elect A (the
>>>majority favourite) although the B supporters strongly disliked her.
>>
>>Let's express this in Range terms to see what it might mean.
>>
>>I'll assume that there are three candidates total, A, B, and C.
>>What has been expressed above could simply be represented by
>>assuming that there are four ranks. A preference gap of two ranks
>>is expressed by ">>". So the range ratings (Range 0-3) are:
>>
>>55: A:3 B:2 C:0
>>45: A:1 B:3 C:0
>
>Yes. Good mapping to Range.
>
>>Hey, why did C even bother to run?
>
>Just to help me in showing that there were more than one strength of
>preferences in each ballot (">", ">>").

But given that C is what could be called an "irrelevant alternative," 
we then wonder why B was not rated at zero by the 55%. That B was 
*not* so rated, we must assume as deliberate. B was not rated at zero 
because the 55% considered B an adequate candidate.

So you end up, if B wins, with a candidate whom *all* voters, as the 
votes were presented, consider either adequate or the best. This is 
an excellent outcome!

Whereas if A wins, you have 45% of the votes who think that A is 
almost as bad as C, someone whom everyone rejects. Not good. Divisive.

>>Anyway, this election, as stated, comes out to be (totals)
>>
>>A: 3 * 55 + 45 = 210
>>B: 2 * 55 + 3 * 45 = 245
>>
>>B wins.
>
>Yes. And the possible voter strategy (approval style maximised
>preferences) associated with this Range feature is one key reason to
>why I started looking for an alternative method that would be capable
>of expressing the strength of preferences but still allow voters to
>vote sincerely even in contentious elections (without fearing that
>some strategists will "spoil" the election results).

I see much better procedures that don't lose the maximizing 
characteristics of Range. Such as the proposal recently suggested: if 
the Range winner differs from the Preference winner (possibly with 
some additional criteria, conditions which indicate that it is 
possible that the Range winner is not a good choice, the most likely 
involving substantial non-rating of the Range winner), then there is 
a ratification election *or* a runoff election.

A runoff, one might argue, would just replicate the original election 
and elect the Preference winner. But not necessarily. The knowledge 
that there was this other candidate who was rated, on the average, 
higher than the Preference winner could lead many people to change 
their vote in the runoff.

A ratification election or a runoff both guarantee that the result 
has the acceptance of the majority, satisfying the intent of the 
Majority Criterion, which is based on the principle of Majority Rule 
and which is only a problem when implemented in a binary fashion with 
more than two outcomes.