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<div class="moz-cite-prefix">On 11/13/2016 3:35 AM, Jameson Quinn
wrote:<br>
<br>
<blockquote type="cite">
<div>What I mean is that if you take a non-election-theorist,
present an election scenario to them, explain who won and why,
and ask how they would strategize in the place of voter X,
they are more likely to suggest counterproductive strategies,
and less likely to see any strategies that actually might
work, in Condorcet than in Bucklin-like systems.</div>
<div><br>
</div>
</blockquote>
<br>
The strategy incentives for Condorcet voting methods vary widely.
Some have a random-fill incentive while others have a truncation
incentive. Some have<br>
a stronger or weaker incentive to equal-top rank than others, and
some are more vulnerable to Burial than others.<br>
<br>
Smith//Approval has a truncation incentive like Bucklin's, only
less strong. In addition Bucklin has an equal-top rank/rate
incentive. I don't see the problem.<br>
<br>
BTW, why does it matter if "non-election-theorists" when asked
suggest "counter-productive strategies"? Shouldn't we be
encouraging sincere voting?<br>
If they don't want to do that, why can't they just take the
strategy advice of their favourites?<br>
<br>
<span class="">35: C >> A=B<br>
33: A>B >> C<br>
32: B>A >> C<br>
<br>
</span>
<blockquote type="cite"><span class="">In Smith//approval, one
vote alone would shift the above honest election; so the fact
that it does not in PAR is indeed notable.</span></blockquote>
<br>
<span class="">I don't see why. The example I gave just happened
to have a close CW. PAR seems to give an A=B tie unless (as I
assume) it breaks tied final<br>
scores in favour of the "leader" (A).<br>
<br>
</span>
<blockquote type="cite"><span class="">In particular: in PAR,
there is no way for the B voters to strategize such that they
win the above election, while still ensuring that C does not
win no matter what the A voters do.<br>
</span></blockquote>
<br>
<span class="">Of course, that is why it's called a "chicken
dilemma". In what method <i>can</i> "</span><span class="">the
B voters to strategize such that they win the above election,
while still ensuring that C does not win no matter what the A
voters do" ??<br>
<br>
</span>
<blockquote type="cite">MJ passes IIA. PAR fails it, as you say,
but passes LIIA. <br>
</blockquote>
<br>
As do some Condorcet methods. It isn't one of the criteria I care
much about.<br>
<br>
As I understand it, IIA can only be met by methods that fail
Majority (like positional methods that pretend that the voters'
ratings are on some scale independent of the<br>
candidates). MJ is a variety of Median Ratings which is
normally claimed to meet Majority. <br>
<br>
I would be a bit surprised if IIA can be met by a method (such as
MJ and Bucklin) by a method that fails Irrelevant Ballots
Independence.<br>
<br>
There is some rubbish about Independence of Irrelevant
Alternatives (IIA) on Electowiki. I'll address that in a later
post.<br>
<br>
Chris Benham<br>
<br>
<br>
On 11/13/2016 3:35 AM, Jameson Quinn wrote:<br>
</div>
<blockquote
cite="mid:CAO82iZw104HcJd==nVCqKGNDuF_z3yzLNH-WQUQVwJ2fsZDDVw@mail.gmail.com"
type="cite">
<div dir="ltr"><br>
<div class="gmail_extra"><br>
<div class="gmail_quote">2016-11-12 10:45 GMT-05:00 C.Benham <span
dir="ltr"><<a moz-do-not-send="true"
href="mailto:cbenham@adam.com.au" target="_blank">cbenham@adam.com.au</a>></span>:<br>
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex">
<div bgcolor="#FFFFFF" text="#000000"><span class="">
<div class="m_-680782387900465520moz-cite-prefix">On
11/12/2016 7:53 AM, Jameson Quinn wrote:<br>
</div>
</span><span class="">
<blockquote type="cite">
<div dir="ltr"><br>
<div class="gmail_extra"><br>
<div class="gmail_quote">2016-11-11 12:50
GMT-05:00 C.Benham <span dir="ltr"><<a
moz-do-not-send="true"
href="mailto:cbenham@adam.com.au"
target="_blank">cbenham@adam.com.au</a>></span>:<br>
<blockquote class="gmail_quote"
style="margin:0px 0px 0px
0.8ex;border-left:1px solid
rgb(204,204,204);padding-left:1ex">
<div bgcolor="#FFFFFF">
<div
class="m_-680782387900465520m_-8048598155404746332gmail-m_-2730114550739300614moz-cite-prefix"><span
class="m_-680782387900465520m_-8048598155404746332gmail-">On 11/11/2016
10:14 PM, Jameson Quinn wrote:<br>
<br>
<blockquote type="cite"> I think that
simple PAR is close enough to FBC
compliance to be an acceptable
proposal.</blockquote>
<br>
</span> I'm afraid I can't see any value
in "close enough" to FBC compliance.
The point of FBC is to give an absolute
guarantee to (possibly uninformed<br>
and not strategically savvy)
greater-evil fearing voters.</div>
</div>
</blockquote>
<div><br>
</div>
<div>Yes. The guarantee you can give is "as
long as the world is somewhere in this
restricted domain — that is, essentially, as
long as there are no Condorcet cycles and
each voter naturally rejects at least one of
the 3 frontrunners — this method meets FBC".
This is much broader than any guarantee you
could give for a typical non-FBC method. For
instance, with IRV, the best you could say
would be "as long as your favorite is
eliminated early or wins overall, you don't
have to betray them", which unlike PAR's
guarantee is not something which could ever
be generally true about all real elections
for all factions.<br>
<br>
</div>
</div>
</div>
</div>
</blockquote>
</span> C: I have in mind voters who are inclined to
Compromise, and so it's <i> absolute guarantee</i> or
it's nothing. Smith//Approval also has a much lower
Compromise incentive<br>
than does IRV (which in turn has a much much lower
Compromise incentive then FPP).<span class=""><br>
<br>
<br>
<blockquote type="cite">
<div dir="ltr">
<div class="gmail_extra">
<div class="gmail_quote">
<div><br>
</div>
<blockquote class="gmail_quote"
style="margin:0px 0px 0px
0.8ex;border-left:1px solid
rgb(204,204,204);padding-left:1ex">
<div bgcolor="#FFFFFF">
<div
class="m_-680782387900465520m_-8048598155404746332gmail-m_-2730114550739300614moz-cite-prefix"><span
class="m_-680782387900465520m_-8048598155404746332gmail-"><br>
<br>
<blockquote type="cite">It elects the
"correct" winner in a chicken
dilemma scenario,
naive/honest/strategyless
ballots, without a "slippery slope"
(though of course, this is no longer
a strong Nash equilibrium). </blockquote>
<br>
</span> How do you have a "chicken
dilemma scenario" with
"naive/honest/strategyless ballots" ?<br>
<br>
35: C >> A=B<br>
33: A>B >> C<br>
32: B >> A=C (sincere is B>A
>> C)<br>
<br>
In this CD scenario your method elects
B in violation of the CD criterion.<br>
</div>
</div>
</blockquote>
<div><br>
</div>
<div>You're suggesting that the sincere
preferences are <br>
</div>
<div><br>
35: C >> A=B<br>
33: A>B >> C<br>
32: B>A >> C<br>
<br>
<br>
</div>
</div>
</div>
</div>
</blockquote>
</span> C: I'm not "suggesting". I'm stating.<span
class=""><br>
<blockquote type="cite">
<div dir="ltr">
<div class="gmail_extra">
<div class="gmail_quote">
<div><br>
</div>
<div>If you are 1 of the B>A>>C
voters considering whether to strategically
vote B>>A=C, you have no strong
motivation to do so, because your vote alone
is not enough to shift the winner to B. This
is what I mean by "no slippery slope".<br>
<br>
<br>
</div>
</div>
</div>
</div>
</blockquote>
</span> C: One "vote alone" is very rarely enough to do
anything, so I suppose no-one has a "strong motivation"
to vote.</div>
</blockquote>
<div><br>
</div>
<div>In Smith//approval, one vote alone would shift the
above honest election; so the fact that it does not in PAR
is indeed notable.</div>
<div><br>
</div>
<div>In particular: in PAR, there is no way for the B voters
to strategize such that they win the above election, while
still ensuring that C does not win no matter what the A
voters do. This "safe" strategizing is grease on the
slippery slope.</div>
<div><br>
</div>
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex">
<div bgcolor="#FFFFFF" text="#000000"><span class=""><br>
<blockquote type="cite">
<div dir="ltr">
<div class="gmail_extra">
<div class="gmail_quote">
<div><br>
</div>
<div><br>
</div>
<div>I believe that in the election you gave,
there is no way to tell what the sincere
preferences are. <br>
<br>
<br>
</div>
</div>
</div>
</div>
</blockquote>
<br>
</span> C: From just the information on the ballots, of
course not (like any election).<span class=""><br>
<blockquote type="cite">
<div dir="ltr">
<div class="gmail_extra">
<div class="gmail_quote">
<div><br>
Perhaps the B voters are strategically
truncating A; perhaps the C voters are
strategically truncating B. So the "correct
winner" could be either A or B, but is
almost certainly not C. <br>
</div>
</div>
</div>
</div>
</blockquote>
<br>
</span> C: By "correct winner" I assume you mean the
sincere CW. But there is reason to assume there is one.
And if the B voters are actively Burying C, it could be
C.<span class=""><br>
<br>
<blockquote type="cite">
<div dir="ltr">
<div class="gmail_extra">
<div class="gmail_quote">
<div>The "CD criterion" requires the system to
elect C, merely to punish the B voters; I
think that's perverse, because, among other
things, it means that a system does badly
with center squeeze, allowing the C faction
to strategize and win.<br>
<br>
</div>
</div>
</div>
</div>
</blockquote>
</span> C: No, it merely says "not B". But CD +
Plurality say that it must be C.<span class=""><br>
<blockquote type="cite">
<div dir="ltr">
<div class="gmail_extra">
<div class="gmail_quote">
<div> </div>
<blockquote class="gmail_quote"
style="margin:0px 0px 0px
0.8ex;border-left:1px solid
rgb(204,204,204);padding-left:1ex">
<div bgcolor="#FFFFFF">
<div
class="m_-680782387900465520m_-8048598155404746332gmail-m_-2730114550739300614moz-cite-prefix">
<br>
Since you are apparently now content to
do without FBC compliance and you
imply that electing the CW is a good
thing,<br>
why don't you advocate a method that
meets the Condorcet criterion?<br>
<br>
What is wrong with Smith//Approval? Or
Forest's nearly equivalent Max Covered
Approval? <br>
</div>
</div>
</blockquote>
<div><br>
</div>
<div>Largely, it's because I think that
Condorcet systems are strategically
counterintuitive, and hard to present
results in. I think that will lead to more
strategy than a system like PAR. That's
because PAR can make guarantees that
Condorcet systems can't.<br>
<br>
</div>
</div>
</div>
</div>
</blockquote>
</span> C: Such as? What exactly does "strategically
counter-intuitive" mean? An example?</div>
</blockquote>
<div><br>
</div>
<div>What I mean is that if you take a
non-election-theorist, present an election scenario to
them, explain who won and why, and ask how they would
strategize in the place of voter X, they are more likely
to suggest counterproductive strategies, and less likely
to see any strategies that actually might work, in
Condorcet than in Bucklin-like systems.</div>
<div><br>
</div>
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex">
<div bgcolor="#FFFFFF" text="#000000"><span class=""><br>
<blockquote type="cite">
<div dir="ltr">
<div class="gmail_extra">
<div class="gmail_quote">
<div><br>
</div>
<div>In a system like MJ or Score, you can
give a number to each candidate, based on
their own ratings alone, and the higher
number wins. That is an easy way to get
monotonicity, FBC, and IIA.</div>
<div><br>
</div>
<div>In Condorcet, no candidate has any number
except in relation to all other candidates.
That's good for passing the Condorcet
criterion (obviously) but it breaks FBC and
IIA.<br>
<br>
</div>
</div>
</div>
</div>
</blockquote>
</span> C: Your method and MJ fail IIA.</div>
</blockquote>
<div><br>
</div>
<div>MJ passes IIA. PAR fails it, as you say, but passes
LIIA. </div>
</div>
<br>
</div>
</div>
<p class="" avgcert""="" color="#000000" align="left"><br>
</p>
</blockquote>
<p>
<blockquote type="cite">
<p>Prefer Accept Reject (PAR) voting works as follows: </p>
<ol>
<li><b>Voters can Prefer, Accept, or Reject each candidate.</b>
Blanks count as "Reject" if no rival is explicitly rejected;
otherwise, blank is "Accept".</li>
<li><b>Candidates with at least 25% Prefer, and no more than
50% reject, are "viable"</b>. The most-preferred viable
candidate (if any) is the leader.</li>
<li> Each "prefer" is worth 1 point. For viable candidates,
each "accept" on a ballot which doesn't prefer the leader is
also worth 1 point. <b>Most points wins.</b></li>
</ol>
</blockquote>
<br>
</p>
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