[EM] STV and weighted positional methods

[Dave Ketchum]

On Sat, 31 Jan 2009 22:46:00 +0000 Raph Frank wrote:
> On Sat, Jan 31, 2009 at 8:30 PM, Kathy Dopp <kathy.dopp at gmail.com> wrote:
> 
>>False. It happens whenever the number of candidates is more than the
>>number of rankings allowed on a ballot plus the number of seats being
>>filled.
> 
> 
> Ok, fair enough.  However, IRV is supposed to allow an unlimited
> number of ranks.  Fairvote seems to try to apply the name to a huge
> range of voting methods, not matter how many ranks are allow.  In
> fact, they may have applied it to instant top-2 runoff.

Eventually you get down to successfully running an election.  Among your 
choices:
      Leave a slot in the ballot by each candidate for voter to write in 
the rank number.   Allows for lots of ranks, but a challenge to decipher 
what the voters write.
      Provide a check off slot by each candidate for each possible rank. 
Three slots will satisfy most voters for most IRV races, provided they 
recognize needs vs abilities.
      Of course, to elect a slate needs more ability.
> 
> This allows them claim it is in use in lots of places.
> 
> Also, if you have 3 ranks, then as long as you give your 3rd rank to
> one of the top-2, you should be OK and certainly not any worse off
> than with plurality.
> 
Depends mostly what you want to accomplish as a voter:
      Get in on top-2 - then rank your preference between these.
      Get in on others such as your own preference - rank per your desire 
in available ranking.
> 
>>>>Also, if you always rank one of the top-2, then you are likely to be
>>>>part of the last round, even if you don't rank everyone.

I would not add to what I wrote above.
>>>
>>Unlike top-two runoff or primary/general elections when I am always
>>allowed to participate in the final counting round no matter who I
>>voted for in the prior election.
> 
Need to get together on ONE topic for this debate.
> 
> Top 2 run-off is also potentially non-monotonic when considered as a whole.
> 
> If you vote for a candidate in round 1, it might mean that you end up
> electing a worse candidate in round 2, due to eliminating a
> compromise.
> 
> Each stage is monotonic when taken individually though.
> 
> 
>>Whoever made this statement makes false unsupported assumptions about
>>my position. While it may be true that plurality is one of the worst
>>voting methods available, there is a far worse voting method than
>>plurality and that is IRV/STV.
> 
> 
> The two methods both tend towards 2 party domination and will likely
> give the same results anyway.
> 
> I think they are both very poor methods.
> 
> 
>>>>I don't think you support plurality in order to maintain the monopoly of current voting machine vendors.
>>>
>>This above statement is hopelessly illogical.
> 
> 
> They point I was making was that I don't think you are acting in bad
> faith.  I don't think your support of plurality over IRV is due to bad
> faith, it is just down to disagreement.
> 
> 
>>>>In Ireland, we count PR-STV by hand and there are various checks that can be accomplished.
>>>
>>I believe that in Ireland you also have far fewer issues and election
>>contests to vote on for each ballot.  Am I wrong?
>>
>>Computer scientists have already mathematically proven that counting
>>IRV/STV is an exponential problem in computer science. Far far more
>>difficult and time-consuming to count accurately than other voting
>>methods. I am fairly certain that your assertion about counting time
>>is incorrect.
> 
Proving difficulty is tricky because it depends on understanding the 
problem.  What I see below sounds like simplifying the problem to make it 
solvable.

Seems like I just read of collecting all the ballots for a race at a 
central counting site.
> 
> Maybe you are thinking of Meek's method (or one of the really complex
> ones like CPO-STV or Schulze-STV)?  They requires a computer.
> 
> Standard PR-STV takes at most one pass through the votes per round and
> in each round, a candidate is elected or eliminated.
> 
> The Irish method is slightly random and is roughly
> 
> Initialisation:
> 
> 1) sort all the ballots into piles based on first choice
> 2) Count all the piles
> 3) work out quota
> 
> Processing (once per round)
> 
> If any candidate has more than the quota in his pile
> -- declare that candidate elected.
> -- Select ballots equal to the surplus from the ballots for that
> candidate at random
> -- They are selected using stratified random sampling (based on next
> highest ranking)
> -- assign those ballots to the other candidates
> Otherwise
> -- declare lowest candidate eliminated
> -- redistribute all the votes in his pile
> 
> The first count requires examination of all the ballots, but the later
> rounds only require looking at the surplus or the ballots for the
> eliminated candidate.  This is a much smaller set of ballots than all
> the ballots.
> 
> The sub-piles are kept separate so as to allow easy checking during
> the recount.  The recount only has to check that each ballot is in a
> valid sub-pile and that the total in the sub-pile matches the original
> count.
-- 
  davek at clarityconnect.com    people.clarityconnect.com/webpages3/davek
  Dave Ketchum   108 Halstead Ave, Owego, NY  13827-1708   607-687-5026
            Do to no one what you would not want done to you.
                  If you want peace, work for justice.