[EM] Election layering effect (or why election-method reform is important)

[Stéphane Rouillon]

  It is not only proportionality, but individual-based support method 
that make the difference.
Using the same  STV will of the electorate, and this possible closed 
lists (B3-B2-B1, R3-R2-R1, Y3-Y2-Y1),
we obtain a different Global individual satisfaction measure, despite 
the fact that we still elect one representative of each political party.
Voters will:
10%: B3 B2 Y2 R1 R2 Y1 Y3 R3 B1
30%: R1 R2 R3 B1 B2 B3 Y1 Y2 Y3
51%: B1 Y1 Y2 Y3 R1 R3 R2 B3 B2
9%: Y1 B1 R1 B2 R2 Y3 Y2 R3 B3
They do their best to maximize their results... (Some of the 51% will 
vote Yellow...)
Elected: B3 R3 Y3.
Individual satisfaction of the first group of voters: 33,3% (two elected 
among the 3 first choices)
Individual satisfaction of the second group of voters: 33,3% (one 
elected among the 3 first choices)
Individual satisfaction of the third group of voters: 0% (none elected 
among the 3 first choices)
Individual satisfaction of the fourth group of voters: 0% (none elected 
among the 3 first choices)
Global individual satisfaction of all voters: 10% x 33,3% + 30% x 33,3% 
+ 51% x 0% + 9% x 0% = 13,3%

A lot worst...
Stéphane

On 2012-05-03 15:46, Kristofer Munsterhjelm wrote:
> On 05/03/2012 09:29 AM, Richard Fobes wrote:
>
>> I like this analogy. It does not amplify enough, yet it prompted me to
>> think of this idea:
>>
>> We tend to think of politics as a pyramid that has our few-in-number
>> leaders at the top, and the numerous voters at the bottom who support
>> the leaders through voting.
>>
>> In contrast, an upside-down pyramid might be more realistic. Each layer
>> in the pyramid corresponds to one of the layers mentioned above. At the
>> bottom are the few voters who marked on their primary-election ballot
>> support for the Congressmen who voted (as part of a majority) to pass a
>> new law. I'm still working out how best to draw it, yet this seems like
>> a useful path to clarify the importance of election-method reform.
>
> I first found this pattern when considering forms of council 
> democracy. In these types of democracy, you have local councils that 
> appoint representatives from their number to form regional councils 
> that appoint representatives... and so on up.
>
> In the worst case, a bare majority at every level can control the 
> whole system. In a one-level system, a majority suffices (which is 
> much less than 100%); in a two-level system, a majority of a majority; 
> in a three level system, a majority of a majority of a majority and so 
> on.
>
> Generally, if the councils are of size n, then a majority m is 
> floor(n/2) + 1. Call the fraction required to get a majority, f. f = 
> m/n, and this approaches 50% as n goes to infinity.
>
> Then in the very worst case, f^(num levels) of the total population 
> suffice to control the council democracy. In a primary system, it's 
> worse since only a fraction of the population can vote in any given 
> primary (excepting open/jungle primaries), and not all who can vote 
> are going to.
>
>> On 4/28/2012 10:52 AM, Stéphane Rouillon wrote:
>>> ...
>>> With an STV election, 3 seats in a single super-district, let's
>> assume ...
>>> ...
>>> Typically STV produces a global individual satisfaction rates around
>>> twice FPTP rates for the simulations
>>> I have made yet...
>>> ...
>>> This does not covers the layering effect of multiple representative
>>> levels, but it emphasizes the mismatch
>>> between the will of electors and the results.
>>>
>>> Stéphane Rouillon
>>
>> Yes, proportional methods reduce the number of wasted votes (which can
>> be defined in various ways). Yet, as you say, this does not address the
>> layering effect. Nevertheless, thank you for your ideas.
>
> In the council model, proportional representation does help, so to 
> some extent it does alleviate the layering effect. If a council elects 
> three instead of one to the next level, then in the worst case, the 
> faction has to get all of them for enough councils to get a sufficient 
> supermajority on the next level, and so on.
>
> In a primary system, I think the most clear benefit is that it 
> dissolves the problem. If you have proportional representation, 
> there's no need for primaries - at least not for legislative 
> elections. Any group that disagrees with the party can simply leave 
> that party to form a party of its own.
>
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