<html>
<head>
<meta content="text/html; charset=utf-8" http-equiv="Content-Type">
</head>
<body bgcolor="#FFFFFF" text="#000000">
<div class="moz-cite-prefix">On 10/19/2016 5:17 AM, Michael Ossipoff
wrote:<br>
<br>
<blockquote type="cite">
<p dir="ltr">Specifically, how would that pushover strategy
work? Make a sure-loser win one of the finalist-choosing
counts, while making your candidate win the other?</p>
<p dir="ltr">Can you give an example?</p>
</blockquote>
Yes, and I'll think about it.<br>
<br>
<blockquote type="cite">Suppose the respective finalists are
chosen by IRV and Implicit Approval, respectively, applied to
the first set of ballots. </blockquote>
<br>
Very easy for this version. If you are happy to see the likely
IRV winner X win, then simply vote X top and then only rank
candidates that you<br>
think X can pairwise beat (taking advantage of IRV's compliance
with Later-no-Harm).<br>
<br>
If things go well for you then if X doesn't win both counts then X
will be the IRV winner and one of the "turkeys" you also approved
will be the<br>
Implicit Approval winner and lose in the run-off to X.<br>
<br>
(And of course if X doesn't make the final you have the happy
fall-back of voting sincerely in the run-off).<br>
<br>
Chris Benham<br>
<br>
</div>
<blockquote
cite="mid:CAOKDY5BjrWXkdg2PC83o4F2My2wZ5xdxWE2SbvtGQdxTEvHiHg@mail.gmail.com"
type="cite">
<p dir="ltr">Specifically, how would that pushover strategy work?
Make a sure-loser win one of the finalist-choosing counts, while
making your candidate win the other?</p>
<p dir="ltr">Can you give an example?</p>
<p dir="ltr">Surely, strategically putting the right winner in
both initial counts--especially if both counts operate on the
same set of ratings--sounds like a daunting task, doesn't it?</p>
<p dir="ltr">Michael Ossipoff</p>
<div class="gmail_quote">On Oct 17, 2016 8:36 PM, "C.Benham" <<a
moz-do-not-send="true" href="mailto:cbenham@adam.com.au">cbenham@adam.com.au</a>>
wrote:<br type="attribution">
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex">
<div bgcolor="#FFFFFF" text="#000000">
<div class="m_-5787891786231176217moz-cite-prefix">This
"each voter has two ballots" idea certainly
(strategically) allows the voter to be completely sincere
on one of them,<br>
but the cost is that the overall method becomes a festival
of fairly easy and obvious Push-over strategising.<br>
<br>
Of course one way to monitor this would be to look at the
(strategically and so presumably) sincere ballots and
discover<br>
who would have won according to various methods on those
ballots.<br>
<br>
(But if that was done openly it might introduce some
incentives based on fear of embarrassment and/or fear
that the<br>
method will be abolished.)<br>
<br>
Chris Benham<br>
<br>
<br>
On 10/18/2016 11:13 AM, Michael Ossipoff wrote:<br>
</div>
<blockquote type="cite">
<p dir="ltr">I think it sounds super. The best yet, with
the best properties of the best methods, avoiding
eachother's faults & vulnerabilities.</p>
<p dir="ltr">More later.</p>
<p dir="ltr">Michael Ossipoff</p>
<div class="gmail_quote">On Oct 17, 2016 1:49 PM, "Forest
Simmons" <<a moz-do-not-send="true"
href="mailto:fsimmons@pcc.edu" target="_blank">fsimmons@pcc.edu</a>>
wrote:<br type="attribution">
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex">
<div dir="ltr">
<div>
<div>
<div>
<div>Kristofer,<br>
<br>
Perhaps the way out is to invite two ballots
from each voter. The first set of ballots is
used to narrow down to two alternatives. It
is expected that these ballots will be voted
with all possible manipulative strategy ...
chicken defection, pushover, burial, etc.<br>
<br>
</div>
The second set is used only to decide between
the two alternatives served up by the first
set.<br>
<br>
</div>
A voter who doesn't like strategic burden need
not contribute to the first set, or could submit
the same ballot to both sets.<br>
<br>
</div>
<div>If both ballots were Olympic Score style,
with scores ranging from blank (=0) to 10, there
would be enough resolution for all practical
purposes. Approval voters could simply specify
their approvals with 10 and leave the other
candidates' scores blank.<br>
<br>
</div>
<div>There should be no consistency requirement
between the two ballots. They should be put in
separate boxes and counted separately. Only
that policy can guarantee the sincerity of the
ballots in the second set.<br>
<br>
</div>
<div>In this regard it is important to realize
that optimal perfect information approval
strategy may require you to approve out of
order, i.e. approve X and not Y even if you
sincerely rate Y higher than X. [We're talking
about optimal in the sense of maximizing your
expectation, meaning the expectation of your
sincere ratings ballot, (your contribution to
the second set).] <br>
<br>
</div>
<div>Nobody expects sincerity on the first set of
ballots. If some of them are sincere, no harm
done, as long as the methods for choosing the
two finalists are reasonable.<br>
<br>
</div>
<div>On the other hand, no rational voter would
vote insincerely on hir contribution to the
second set. The social scientist has a near
perfect window into the sincere preferences of
the voters.<br>
<br>
</div>
<div>Suppose the respective finalists are chosen
by IRV and Implicit Approval, respectively,
applied to the first set of ballots. People's
eyes would be opened when they saw how often the
Approval Winner was sincerely preferred over the
IRV winner.<br>
<br>
</div>
<div>Currently my first choice of methods for
choosing the respective finalists would be MMPO
for one of them and Approval for the other, with
the approval cutoff at midrange (so scores of
six through ten represent approval).<br>
<br>
</div>
<div>Consider the strategical ballot set profile
conforming to<br>
<br>
</div>
<div>40 C<br>
</div>
<div>32 A>B<br>
</div>
<div>28 B<br>
<br>
</div>
<div>The MMPO finalist would be A, and the likely
Approval finalist would be B, unless too many B
ratings were below midrange.<br>
<br>
</div>
<div>If the sincere ballots were<br>
<br>
</div>
<div>40 C<br>
</div>
<div>32 A>B<br>
</div>
<div>28 B>A<br>
<br>
</div>
<div>then the runoff winner determined by the
second set of ballots would be A, the CWs. The
chicken defection was to no avail. Note that
even though this violates Plurality on the first
set of ballots, it does not on the sincere set.<br>
<br>
</div>
<div>On the other hand, if the sincere set
conformed to<br>
<br>
</div>
<div>40 C>B<br>
</div>
<div>32 A>B<br>
</div>
<div>28 B>C<br>
<br>
</div>
<div>then the runoff winner would be B, the CWs,
and the C faction attempt to win by truncation
of B would have no effect. A burial of B by the
C faction would be no more rewarding than their
truncation of B.<br>
<br>
</div>
<div>So this idea seems to take care of the
tension between methods that are immune to
burial and methods that are immune to chicken
defection.<br>
<br>
</div>
<div>Furthermore, the plurality problem of MMPO
evaporates. Even if all of the voters vote
approval style in either or both sets of
ballots, the Plurality problem will
automatically evaporate; on approval style
ballots the Approval winner pairwise beats all
other candidates, including the MMPO candidate
(if different from the approval winner).<br>
<br>
</div>
<div>What do you think?<br>
<br>
</div>
<div>Forest<br>
</div>
<div><br>
<br>
</div>
<div><br>
</div>
<br>
</div>
<div class="gmail_extra"><br>
<div class="gmail_quote">On Sun, Oct 16, 2016 at
1:30 AM, Kristofer Munsterhjelm <span dir="ltr"><<a
moz-do-not-send="true"
href="mailto:km_elmet@t-online.de"
target="_blank">km_elmet@t-online.de</a>></span>
wrote:<br>
<blockquote class="gmail_quote" style="margin:0
0 0 .8ex;border-left:1px #ccc
solid;padding-left:1ex"><span>On 10/15/2016
11:56 PM, Forest Simmons wrote:<br>
> Thanks, Kristofer; it seems to be a
folk theorem waiting for formalization.<br>
><br>
> That reminds me that someone once
pointed out that almost all of the<br>
> methods favored by EM list enthusiasts
reduce to Approval when only top<br>
> and bottom votes are used, in
particular when Condorcet methods allow<br>
> equal top and multiple truncation votes
they fall into this category<br>
> because the Approval Winner is the
pairwise winner for approval style<br>
> ballots.<br>
><br>
> Everything else (besides approval
strategy) that we do seems to be an<br>
> effort to lift the strategical burden
from the voter. We would like to<br>
> remove that burden in all cases, but at
least in the zero info case.<br>
> Yet that simple goal is somewhat
elusive as well.<br>
<br>
</span>Suppose we have a proof for such a
theorem. Then you could have a<br>
gradient argument going like this:<br>
<br>
- If you're never harmed by ranking Approval
style, then you should do so.<br>
- But figuring out the correct threshold to
use is tough (strategic burden)<br>
- So you may err, which leads to a problem.
And even if you don't, if<br>
the voters feel they have to burden their
minds, that's a bad thing.<br>
<br>
Here, traditional game theory would probably
pick some kind of mixed<br>
strategy, where you "exaggerate"
(Approval-ize) only to the extent that<br>
you benefit even when taking your errors into
account. But such an<br>
equilibrium is unrealistic (we'd have to find
out why, but probably<br>
because it would in the worst case require
everybody to know about<br>
everybody else's level of bounded
rationality).<br>
<br>
And if the erring causes sufficiently bad
results, we're left with two<br>
possibilities:<br>
<br>
- Either suppose that the method is
sufficiently robust that most voters<br>
won't use Approval strategy (e.g. the pro-MJ
argument that Approval<br>
strategy only is a benefit if enough people
use it, so most people<br>
won't, so we'll have a correlated equilibrium
of sorts)<br>
<br>
- That any admissible method must have a "bump
in the road" on the way<br>
from a honest vote to an Approval vote, where
moving closer to<br>
Approval-style harms the voter. Then a
game-theoretical voter only votes<br>
Approval style if he can coordinate with
enough other voters to pass the<br>
bump, which again is unrealistic.<br>
<br>
But solution #2 will probably destroy quite a
few nice properties (like<br>
monotonicity + FBC; if the proof is by
contradiction, then we'd know<br>
some property combinations we'd have to
violate). So we can't have it all.<br>
</blockquote>
</div>
<br>
</div>
</div>
</blockquote>
</div>
<br>
<fieldset
class="m_-5787891786231176217mimeAttachmentHeader"></fieldset>
<br>
<pre>----
Election-Methods mailing list - see <a moz-do-not-send="true" class="m_-5787891786231176217moz-txt-link-freetext" href="http://electorama.com/em" target="_blank">http://electorama.com/em</a> for list info
</pre>
<br>
<fieldset
class="m_-5787891786231176217mimeAttachmentHeader"></fieldset>
<br>
<p color="#000000" align="left">No virus found in this
message.<br>
Checked by AVG - <a moz-do-not-send="true"
href="http://www.avg.com" target="_blank">www.avg.com</a><br>
Version: 2016.0.7797 / Virus Database: 4664/13226 -
Release Date: 10/17/16</p>
</blockquote>
<p><br>
</p>
</div>
</blockquote>
</div>
<p class="" avgcert""="" color="#000000" align="left">No virus
found in this message.<br>
Checked by AVG - <a moz-do-not-send="true"
href="http://www.avg.com">www.avg.com</a><br>
Version: 2016.0.7797 / Virus Database: 4664/13232 - Release
Date: 10/18/16</p>
</blockquote>
<p><br>
</p>
</body>
</html>