Smith//Score ?
Hi Forest,
Le mardi 25 janvier 2022, 01:30:04 UTC−6, Forest Simmons forest.simmons21@gmail.com a écrit :
Score Chain Climbing generally disappoints both burial and Burr dilemma defectors.
That's why it is becoming my favorite method.
SCC
While more than one candidate remains eliminate the highest score candidate that
does not pairwise defeat the lowest score remaining candidate.
The Burr defector, like the burial culprit is typically a fairly strong
candidate that sees a chance to bury or truncate an opponent that he does not
defeat pairwise, but might well come out ahead of if the opponent's score is
lowered.
SCC is practically tailor made to disappoint this kind of manipulation ... the
lowered score candidate still defeats her detractor pairwise, and her lowered
score makes her the pairwise eliminator at some early stage ... the lower her
score, the earlier her chance for revenge!
I'm not sure I'm following your logic. In a three-candidate cycle, the chain
climbing methods (like TACC) elect whichever candidate defeats the weakest
candidate, according to the strength metric being used (implicit approval or
Score etc.). Right?
At first glance this doesn't sound promising from a burial perspective because
if we have a non-CW candidate (the "rival") with strategizers, we expect them to
defeat the "pawn" pairwise and we would often expect that pawn to be the weakest
of the three candidates. That suggests that the rival will succeed in their
strategy most of the time (unless they accidentally turn the pawn into the CW).
Yet experimentally I have found TACC (with implicit approval) to have relatively
low burial incentive. Better than C//A(implicit) and C//FPP, but worse than
fpA-fpC or C//IRV or BPW.
How can this be? I believe it's because with TACC, the act of giving the pawn
new, falsified preferences is quite likely to cause the pawn to no longer be
the weakest candidate by the metric of implicit approval. That is, the failure
situation for TACC doesn't occur as predictably or as often as we might be
inclined to guess.
Indeed running simulations on the TACC algorithm but using first preferences
instead of implicit approval, I find some of the highest burial incentive
anywhere.
This makes me believe that SCC is not going to be as good as TACC, since it
does less to ensure that the weakest candidate (by Score) won't be the pawn in
the strategy.
Kevin
Hi Kristofer,
As a Seattle resident, I have been thinking about approval-like primary
methods recently, and was just musing about a 3-2-1 variant with chain
climbing.
It seems to me that Forest's TACC/Q&C variants are almost perfect with 3
candidates, but can have problems with more.
What if there were a method based on a 3-slot ballot [Preferred,
Acceptable, Reject] with an initial round to cull down to 3 candidates?
With Preferred + Acceptable being approved.
My thought was to use a clone-proofed version of Jameson Quinn's Vote321:
Voters give each candidate a score of Preferred, Acceptable, or Reject.
Of the top 3 approved candidates, included the top two Preferred candidates
in the next round. Call the candidate with higher preference of those two
APW.
Also include the most approved candidate on ballots that don't approve of
APW.
Now you have three candidates, and a ranking from your ballots.
You could run TACC, SCC, or Q&C on the ballots, or use this as a
"top-three" primary for a subsequent election.
A problem with this would be that you could potentially choose a bad combo
of candidates from Smith.
On Tue, Jan 25, 2022 at 1:54 AM Kristofer Munsterhjelm km_elmet@t-online.de
wrote:
On 25.01.2022 08:29, Forest Simmons wrote:
El lun., 24 de ene. de 2022 2:46 p. m., Kristofer Munsterhjelm
<km_elmet@t-online.de mailto:km_elmet@t-online.de> escribió:
On 24.01.2022 22:42, Forest Simmons wrote:
Note that Smith//Score is the same as Smith,Score.
That gives me an idea. How about Smith//Lp-cumulative?
That is, first remove everybody who's not part of the Smith set.
Renormalize all ballots to have unit p-norm. Then greatest score
wins.
It probably isn't monotone, but the renormalization should mitigate
at
least some of the Burr dilemma problems of plain Range.
Score Chain Climbing generally disappoints both burial and Burr dilemma
defectors.
That's why it is becoming my favorite method.
SCC
While more than one candidate remains eliminate the highest score
candidate that does not pairwise defeat the lowest score remaining
candidate.
The Burr defector, like the burial culprit is typically a fairly strong
candidate that sees a chance to bury or truncate an opponent that he
does not defeat pairwise, but might well come out ahead of if the
opponent's score is lowered.
I'll have to check the performance of SCC when/if I make a simulator to
quick-test methods. I had the impression, though, that it produced some
strange honest results? That might have been the Borda variant, though,
so I'm not going to say it's bad on such a weak memory. Or I might be
misremembering altogether.
By the way, I usually consider the Approval/Range Burr dilemma fallout
to be mostly about honest miscalculation. E.g. suppose you want to vote
Perfect > Good > Bad in Approval. You misjudge the polls or vote early
and so you approve Perfect alone. Then Bad wins because Good doesn't
have enough support.
If there were only one honest ballot, then deliberately strengthening
Perfect>others at the expense of weakening Good>Bad would be a strategy.
But since Approval has multiple honest votes, even honest voters are
faced with the dilemma. And so they're the ones who have to deal with
the fallout.
It's kind of like monotonicity that way. Sure, you can strategize with
it, but that's not why it's bad :-)
-km
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