headers
Dave Ketchum | 2 Dec 2007 16:23

Re: [Election-Methods] Is this Condorcet method reasonable?

Agreed margins is better, though I do not see this test case as proof.

Also, rules should be neutral as to promoting or discouraging truncation.

AND, rules should be simple, to promote voters being able to understand them.

I happily throw darts at IRV, noting that Condorcet is summable, while its 
cousin, IRV, is not.

On Fri, 30 Nov 2007 10:06:32 -0300 Diego Santos wrote:
> There were many discussions in this mailing list about advantages of 
> winning votes as counterstrategy against order reversal. But sometimes 
> truncation is risky. Consider this example:
> 
> 46: A > B > C
> 44: C > B > A
> 10: B > A > C
> 
> B is CW.

Agreed.
> 
> Offensive strategy by A voters:
> 
> 46: A > C > B
> 44: C > B > A
> 10: B > A > C
> 
> A wins under RP(wv) or margins.
(Continue reading)

Permalink | Reply | 2 comments |
headers
Kevin Venzke | 2 Dec 2007 19:33
Picon
Favicon

[Election-Methods] RE : Re: Is this Condorcet method reasonable?

Dave,

--- Dave Ketchum <davek <at> clarityconnect.com> a écrit :
> > Offensive strategy by A voters:
> > 
> > 46: A > C > B
> > 44: C > B > A
> > 10: B > A > C
> > 
> > A wins under RP(wv) or margins.
> 
> ??? A voters say they like C better than B - suspicious for, to me, this 
> makes a cycle with C winning (90>10 voters prefer C>B; 56>44 A>C; 54>46
> B>A.

A wins the cycle because A's loss to B is the weakest loss.

Kevin Venzke

      _____________________________________________________________________________ 
Ne gardez plus qu'une seule adresse mail ! Copiez vos mails vers Yahoo! Mail 

----
Election-Methods mailing list - see http://electorama.com/em for list info
Permalink | Reply | 1 comment |
headers
Kevin Venzke | 2 Dec 2007 20:06
Picon
Favicon

[Election-Methods] RE : Re: RE : Is this Condorcet method reasonable?

Hi Diego,

--- Diego Santos <diego.renato <at> gmail.com> a écrit :
> 2007/11/30, Kevin Venzke <stepjak <at> yahoo.fr>:
> > I agree, they should. But how can you promise it?
> 
> I cannot do it. But pairwise sorted plurality, like DMC, gives more
> freedom
> than winning votes, because wv advantage over margins is based in
> truncation.

I think it's an illusion that you have less freedom with WV. You get to
rank more sincerely above the point that you truncate. It's more likely
that you can safely vote for your favorite candidate. Under margins it is a
good strategy to list a viable candidate as your favorite, because margins
doesn't really care how viable/strong a candidate is (i.e. how many votes
he receives in absolute terms) when sorting the defeats. Therefore you had
best try not to give your viable compromise choice any defeats.

And just because a method gives no incentive to truncate, doesn't mean you
can safely fill out the lower preferences sincerely, anyway.

Kevin Venzke

      _____________________________________________________________________________ 
Ne gardez plus qu'une seule adresse mail ! Copiez vos mails vers Yahoo! Mail 

----
Election-Methods mailing list - see http://electorama.com/em for list info
(Continue reading)

Permalink | Reply | 0 comments |
headers
Juho | 2 Dec 2007 23:23
Picon
Favicon

Re: [Election-Methods] RE : Is this Condorcet method reasonable?

On Nov 30, 2007, at 19:33 , Diego Santos wrote:

> I think that cloneproof violation is not severe when a method meets  
> Smith. Probably near all majority rule cycles in contetions  
> elections will be caused by burying. Then, additional resistance to  
> this strategy will be desirable for a Condorcet method. If clone  
> independence is desirable too, "Smith,IRV" is an alternative.

Why do you expect burying to be the main reason to cycles? Does this  
apply to exceptionally contentious elections only or to all typical  
elections?

The cycles may also be caused also by "random like" variation in  
opinions in close races. Also natural cycles where the voter opinions  
really are cyclic are quite possible.

Factors that may reduce the probability of strategic cycles are e.g.  
changing opinion poll results before the elections and inability of  
the voters to use the strategies in the strategically optimal way.

In general I tend to think that Condorcet methods are at their best  
when strategic voting is not widespread or is not well organized  
(=hopefully reduces to just noise). I really wouldn't like to see  
general public use all the various Condorcet strategies that are  
discussed on this list. In most cases Condorcet based methods are  
maybe immune enough to strategic voting (especially when compared to  
other commonly used methods). If this is the case then the best  
method may be the one that performs best with sincere votes (possibly  
slightly random and marginally strategic).
(Continue reading)

Permalink | Reply | 11 comments |
headers
Peter Barath | 3 Dec 2007 00:11
Picon
Favicon

Re: [Election-Methods] Spearman-unbiased apportionment

>* r is the rounding function r(x) = x > m(floor(x), ceil(x)) ?
> ceil(x) : floor(x), where m is a generalized mean function

Not about this problem, but I am reminded of a conversation
many years ago. I don't remember who mentioned, without any
practical reference, only as a mathemathical curiosity, that
if we are to elect numbers of representatives in differently
populated districts, the "true" method is when the number of
the representatives is proportional to the square root of
the population.

As far as I can remember, it was something about the
probability of being a pivotal voter. (Which also gets
a big role in the theorization of the Clarke-tax.)

I'm not sure if I would be able to check it, but somehow
my feeling is that it can easily be well grounded.

At least if we think of the representatives as clones who
always vote the same way. If there are parties and the
representatives are party-proportional, this remark seems
invalid to me.

Peter Barath

____________________________________________________________________
Tavaszig, most minden féláron! ADSL Internet már 1 745 Ft/hó -tól.
Keresse ajánlatunkat a http://www.freestart.hu oldalon!
----
Election-Methods mailing list - see http://electorama.com/em for list info
(Continue reading)

Permalink | Reply | 3 comments |
headers
Peter Barath | 3 Dec 2007 00:12
Picon
Favicon

[Election-Methods] the ladder vote

Sorry if the thing already has a name.

Let's suppose there is a vote, where the voters are
to chose from a number of numbers. For example,
the membership fee of the club, the minimum age
of application, the size of the office, anything.

Something where we can suppose: If a person prefers
number a over number b, and a > b > c then she will
prefer b over c (because c is even further from a).

Also, if she prefers a over b and a < b < c then she
will prefer b over c (because c is even further from a).

Scenario one. They vote by everyone giving her first
preference then they search the median value. For example:

Let the membership fee be:

200$     7 votes
------------------------------- (-)
180$     16 votes
------------------------------- (-)
150$     23 votes
------------------------------- (+)
140$     9 votes
------------------------------- (+)
100$     32 votes
------------------------------- (+)
70$      2 votes
(Continue reading)

Permalink | Reply | 1 comment |
headers
Dave Ketchum | 3 Dec 2007 02:51

Re: [Election-Methods] RE : Re: Is this Condorcet method reasonable?

Apologies!  I picked what looked good to me as a winner, and then assumed 
I understood compatible rules.

Since I had the rules wrong, please forget what I said based on them.

DWK

On Sun, 2 Dec 2007 19:33:55 +0100 (CET) Kevin Venzke wrote:
> Dave,
> 
> --- Dave Ketchum <davek <at> clarityconnect.com> a écrit :
> 
>>>Offensive strategy by A voters:
>>>
>>>46: A > C > B
>>>44: C > B > A
>>>10: B > A > C
>>>
>>>A wins under RP(wv) or margins.
>>
>>??? A voters say they like C better than B - suspicious for, to me, this 
>>makes a cycle with C winning (90>10 voters prefer C>B; 56>44 A>C; 54>46
>>B>A.
> 
> 
> A wins the cycle because A's loss to B is the weakest loss.
> 
> Kevin Venzke
--

-- 
  davek <at> clarityconnect.com    people.clarityconnect.com/webpages3/davek
(Continue reading)

Permalink | Reply | 0 comments |
headers
Steve Eppley | 3 Dec 2007 16:43
Picon
Favicon

Re: [Election-Methods] RE : Is this Condorcet method reasonable?

Perhaps I failed to emphasize, when I mentioned the withdrawal option a 
few days ago, that it sharply reduces the incentive to vote 
strategically?  A candidate strategically raised over the sincere winner 
could withdraw if necessary to elect the sincere winner, and typically 
would have strong incentives to do so, so why would voters bother 
organizing to misrepresent their preferences?

If it is agreed that the withdrawal option sharply reduces the voters' 
incentive to vote strategically, then it makes little sense to choose a 
voting method based on comparisons only of methods that don't permit 
withdrawal, and then graft withdrawal onto the chosen method.  It makes 
more sense to include methods that permit withdrawal in the set of 
methods being compared, and choose a method from this larger set.

--Steve
-------------------
Juho wrote:
> On Nov 30, 2007, at 19:33 , Diego Santos wrote:
>
>   
>> I think that cloneproof violation is not severe when a method meets  
>> Smith. Probably near all majority rule cycles in contetions  
>> elections will be caused by burying. Then, additional resistance to  
>> this strategy will be desirable for a Condorcet method. If clone  
>> independence is desirable too, "Smith,IRV" is an alternative.
>>     
>
> Why do you expect burying to be the main reason to cycles? Does this  
> apply to exceptionally contentious elections only or to all typical  
> elections?
(Continue reading)

Permalink | Reply | 10 comments |
headers
Steve Eppley | 3 Dec 2007 22:55
Picon
Favicon

Re: [Election-Methods] the ladder vote

Peter Barath wrote:
> Sorry if the thing already has a name.
>
> Let's suppose there is a vote, where the voters are
> to chose from a number of numbers. For example,
> the membership fee of the club, the minimum age
> of application, the size of the office, anything.
>
> Something where we can suppose: If a person prefers
> number a over number b, and a > b > c then she will
> prefer b over c (because c is even further from a).
>
> Also, if she prefers a over b and a < b < c then she
> will prefer b over c (because c is even further from a).
>
> Scenario one. They vote by everyone giving her first
> preference then they search the median value. For example:
>
> Let the membership fee be:
>
> 200$     7 votes
> ------------------------------- (-)
> 180$     16 votes
> ------------------------------- (-)
> 150$     23 votes
> ------------------------------- (+)
> 140$     9 votes
> ------------------------------- (+)
> 100$     32 votes
> ------------------------------- (+)
(Continue reading)

Permalink | Reply | 0 comments |
headers
Steve Eppley | 3 Dec 2007 22:58
Picon
Favicon

Re: [Election-Methods] Spearman-unbiased apportionment

Peter Barath wrote:
-snip-
> ...      I am reminded of a conversation
> many years ago. I don't remember who mentioned, without any
> practical reference, only as a mathemathical curiosity, that
> if we are to elect numbers of representatives in differently
> populated districts, the "true" method is when the number of
> the representatives is proportional to the square root of
> the population.
>
> As far as I can remember, it was something about the
> probability of being a pivotal voter. (Which also gets
> a big role in the theorization of the Clarke-tax.)
>
> I'm not sure if I would be able to check it, but somehow
> my feeling is that it can easily be well grounded.
>
> At least if we think of the representatives as clones who
> always vote the same way. If there are parties and the
> representatives are party-proportional, this remark seems
> invalid to me.
>
> Peter Barath
>
> ____________________________________________________________________
> Tavaszig, most minden féláron! ADSL Internet már 1 745 Ft/hó -tól.
> Keresse ajánlatunkat a http://www.freestart.hu oldalon!
> ----
>
(Continue reading)

Permalink | Reply | 2 comments |

Gmane