Re: [EM] A design flaw in the electoral system

2011-10-05 Thread Michael Allan
James, Juho and Fred, Thanks very much for looking at the argument.

  An individual vote has no effect on the formal outcome of the
  election; whether the vote is cast or not, the outcome is the same
  regardless.

James Gilmour wrote:
 These statements worry me - surely they contain a logical flaw?  If
 these statements were true and every elector responded rationally,
 no-one would ever vote.  Then the outcome would not be the same.

It's an interesting distinction, and it might help in answering a
question I have about how people respond to this information (more on
that below).  But here I think you're looking at the effect of knowing
(if indeed it is true) that a vote has no effect, whereas I'm looking
at the effect of that vote itself.

Maybe the easiest way to understand it is in retrospect, by looking at
past votes that you cast.  I make a statement concerning each of those
votes and its actual effect in the objective world.

Juho Laatu wrote:
 I think it is incorrect or at least misleading to say that
 individual votes do not have any influence. They do, as a group.

If it had no bearing on the argument, then I might agree it's
misleading to say it.  But it's actually the premise of the argument.
Yesterday I wrote to another correspondent:

   A more direct answer [how is it possible?] is in the rounding
   procedure that translates a fine-grained sum into a coarse-grained
   outcome (who gets into office).  In that rounding, the effect of
   the fine grain is lost. ...

   Or, we might stand on empirical grounds and state: the measureable
   effect of an individual vote on the outcome is zero.  Which raises
   another question, Why are people surprised to learn this?

James's observation that no-one would ever vote if they accepted the
truth of it might figure into the answer.  But I think the fact itself
is indisputable, a matter of empirical science.  A simple thought
experiment will demonstrate this:

   1. Take the last election in which you voted, and look at its
  outcome (P).
   2. Subtract your vote from that election.
   3. Recalculate the outcome without your vote (Q).
   4. Look at the difference between P and Q.
   5. Repeat for all the elections you ever participated in.

Your vote never made a difference.  Most people feel uncomfortable or
perplexed in this knowledge, and I think the feeling indicates that
something's wrong.

Fred Gohlke wrote:
 I am not entirely clear on the flow of logic in your abstract, but I
 get the sense that you're saying voters should be able to cast their
 vote and have it, too ...
 
 Voters are not pieces of cake.  The act of voting does not
 remove their needs and desires from the political system.
 They should be able to continue to influence the political
 process after they've voted.

I say that electors are physically separated from their ballots, and I
explain why this procedure is necessarily a design flaw.  I trace
other flaws, faults and failures back to this (including the
meaningless vote).  But I say nothing about how to deal with the
situation.  I think we lack an understanding of the overall problem,
so I'm just trying to figure it out.

 If I am offered options that affect my life, options that I've had
 no voice in defining, the ability to choose one of them is neither
 free nor democratic.  On the contrary, it expresses my status as a
 subject of those who defined the options.  The right to vote in such
 circumstances is a farce.

Yet, I believe this too can be traced to the design flaw in the
electoral system.  It's surprising a single flaw could propagate so
many failures, in such different forms, but it appears to be the case.

This draft section (design flaw) dealt only with the flaw itself, and
how it renders the results of the election technically invalid.  Other
sections (not yet drafted) will attempt to uncover the paths by which
the design flaw propagates through society at large.

-- 
Michael Allan

Toronto, +1 416-699-9528
http://zelea.com/


James Gilmour wrote:
 Michael Allan   Sent: Monday, October 03, 2011 9:31 AM
  ABSTRACT
  
  An individual vote has no effect on the formal outcome of the 
  election; whether the vote is cast or not, the outcome is the 
  same regardless.
 
 These statements worry me  -  surely they contain a logical flaw?  If these 
 statements were true and every elector responded
 rationally, no-one would ever vote.  Then the outcome would not be the same.
 
 I am not into logic, but I suspect the flaw is in some disconnection 
 between the individual and the aggregate.  When A with 100
 votes wins over B with 99 votes, we cannot say which of the 100 individual 
 votes for A was the winning vote, but it is clear that
 is any one of those 100 votes had not been for A, then A would not have won.  
 At best, if one A-voter had stayed at home, there
 would have been a tie.  If one of the A-voters had voted for B instead, the 
 outcome would have been very different.
 
 Or am 

Re: [EM] Enhanced DMC

2011-10-05 Thread Chris Benham
I  like this.  Regarding how approval is inferred, I'm also happy with Forest's 
idea of using Range 
(aka Score) type ballots (on which voters give their most preferred candidates 
the highest numerical 
scores) and interpreting any score above zero as approval and breaking approval 
ties as any score
above 1 etc.  Or any other sort of  multi-slot ratings ballot where all except 
the bottom-most slot is
interpreted as approval.
 
Another idea is to enter above-bottom equal-ranking between any 2 candidates in 
the pairwise matrix
as a whole vote for both candidates, and then take each candidate X's highest 
single pairwise score
as X's approval score.
 
Here are a couple of examples to demonstrate how this method varies from some 
other Condorcet
methods.

48: A
01: AD
24: BD
27: CBD
 
D is the most approved candidate and in the Smith set, and so Smith//Approval 
elects D.
Forest's Enhanced DMC or  Covering DMC  (and your suggested SARR 
implementation)
elects B.

B covers D and to me looks like a better winner. This method has a weaker 
truncation incentive 
than Smith//Approval.

25: AB
27: BC
26: CA
22: C

Approvals: C75,  B52, A51.    AB 51-49,   BC 52-48,   CA 75-25
 
Plain DMC and using MinMax or one of the algorithms that is equivalent to it 
when there are three
candidates (such as Schulze and Ranked Pairs and River) and weighing defeats 
either by Winning
Votes or Margins all elect B.
 
If  5 of  the 22 C voters change to A those methods all elect C (a failure of  
Woodall's mono-sub-delete
criterion).
 25: AB
27: BC
26: CA
17: C

05: A  (was C)
 
Approvals: C70,  A56,  B52.    AB 56-49,   BC 52-48,   CA 70-30.
 
In both cases our favoured method (like Smith//Approval) elects C, the  
positionally dominant candidate. It 
seems those other methods are more vulnerable to Push-over strategy.
 
(To be fair, Woodall has demonstrated that no Condorcet method can meet 
mono-raise-delete.)
 
 
Chris Benham
  



From: Ted Stern araucaria.arauc...@gmail.com
To: election-methods@lists.electorama.com
Cc: Forest Simmons fsimm...@pcc.edu; Chris Benham cbenha...@yahoo.com.au
Sent: Wednesday, 5 October 2011 8:35 AM
Subject: Re: [EM] Enhanced DMC

After some private email exchanges with Forest and Chris, I'm
proposing a simple way of implementing Enhanced DMC, plus a new name,
Strong Approval Round Robin Voting (SARR Voting).

Ballot:

Ranked Voting, all explicitly ranked candidates considered approved.
Equal ranking allowed.  I'm basing this on recommendation from Chris
Benham.  I'm open to alternatives, but it seems to be the easiest way
to do it for now, and the most resistant to burying strategies.

Tallying:

Form the pairwise matrix, using the standard Condorcet procedure.  In
the diagonal entries, save total Approval votes.

For N candidates, the list of candidates in order from highest to
lowest approval is

  X_0, X_1, ..., X_k, X_{k+1}, ..., X_{N-1}

Initialize the Strong set to the empty set

Initialize the Weak set to the empty set.

For k = 0 to N-1,

  If X_k is already in the Weak set, continue iterating.  (X_k is
  defeated by a higher approved candidate.  This is called being
  strongly defeated.)

  If X_k loses to a member of the Weak set, continue iterating.  (X_k
  may defeat all higher approved candidates, but is weakly defeated
  by at least one of them.)
  
  If we're still here in the loop, X_k defeats all candidates in the
  Strong Set and all candidates in the Weak set.  (X_k covers all
  previously added members of the Strong set.)

  Add X_k to the Strong set and add all of X_k's defeats to the Weak
  set.

  Set the provisional winner to X_k.

The last provisional winner (the last candidate added to the Strong
set) is the winner of the election.

Note:

The first member of the Strong Set will be X_0.

It is easiest to do this by hand if you first permute the pairwise
array so that it follows the same X_0, ..., X_{N-1} ordering.

As an example election, consider the one on this page:

  http://wiki.electorama.com/wiki/Marginal_Ranked_Approval_Voting

Iterating through E, A, C, B, D, we find

  E:  Strong and Weak Sets are empty, so E has no losses to either.

      Strong set = {E};          Weak set = {C, D}
  
      Provisional winner set to E.

  A:  A defeats Strong set {E} and Weak set {C, D}.

    = Strong set = {E, A};      Weak set = {C, D}

      Provisional winner set to A.

  C:  in Weak set, not added to Strong set.

  B:  Defeats A, but is defeated by D from Weak set (and is therefore
      weakly defeated by A).

  D:  in Weak set, not added to Strong set.

A is the last candidate added to the Strong set, so A wins.

Ted
-- 
araucaria dot araucana at gmail dot com

On 26 Sep 2011 11:44:13 -0700, Chris Benham wrote:

 Forest,

 I think in general that if the approval scores are at all valid I
 would go for the enhanced DMC winner over any of the chain building
 methods we have considered. I think other considerations over-ride
 the