[EM] Chris: Approval

[Michael Ossipoff]

I'd said:

Obviously majority rule is violated by an outcome that is contrary to what 
a majority have voted that they want. For instance, if a majority vote B 
over A, then we can assume that, if A or B wins, they vote that it be B.


Chris says:

That is reasonable, and granted for the sake of argument. That implies that 
you agree with Kevin Venzke that Minimal Defense(MD) must be met


It does?? I don't agree with Keviln Venzke that Minimal Defense (MD) must be 
met.


We've discussed this before. I have never advocated Minimal Defense.It's 
completely different from SDSC, on which it's based.


But I don’t even say that SDSC must be met. Approval doesn’t meet SDSC. I do 
say that there’s no point proposing a rank method without SFC and SDSC.


Chris continues:

no-matter-what, but while I think MD compliance can be a positive for an 
otherwise bad method I think the best methods can do without it.


Maybe, but if you do without SFC & SDSC, you're doing without the strategy 
guarantees that justify using rank balloting.




49: A
24: B
27: C|B

MD says "not A", but A is the only candidate in the Definite Majority set. 
(C knocks out B, and A knocks out C).


Ah well, that settles it, if the definite majority set says so. :-)

A majority say that, if it's B or A, it should be B. That means don't elect 
A. A is the only candidate with a majority against him.





[after a discussion of what majority rule means for single-winner outcoms]

That opens up the question of how best to measure the strength of pairwise 
defeats. Alternative algorithms for DMC are Beatpath(Total Approval),
River(TA), Ranked Pairs(TA) which all measure the strength of a pairwise 
defeat by the approval score of the pairwise winner.


Fine, measure defeat-strength that way if it results in a guarantee that's 
important to you.


DAMC measures strength in that way, but looks only at majority defeats, and 
does alright. But TA by itself won't do nearly as well.


At least in the "three candidates in the top cycle" situation, an 
alternative algorithm for ASM is Approval Margins that uses one of 
River,BP,RP
and measures pairwise defeat strengths by the difference between the 
approval scores of the two candidates. Both DMC and ASM meet the

Definite Majority criterion.


No doubt that criterion may be important to you.

[After an example]

Here {A} is not just the Definite Majority set but also the "Definite 
Absolute Majority" set


No shit!  Again, defining those sets doesn’t make them official 
standard.
If you want to say that they’re important, then you need to tell exactly 
why. Just citing them like some kind of authority doesn’t mean anything.



(which doesn't conflict with MD),
so I can't see how anyone can credibly claim that electing A here flouts 
"majority rule".


I reply:

Forgive me for being unfashionable, but a majority have indicated that if 
it's B or A, it should be B.
That B>A majority defeat isn't nullified by being in a cycle of defeats at 
least equally strong.


Yes, you or someone have made up a "definilte majority set" and a "definite 
absolute majority set", but you must understand that that does not mean that 
they automatically become the definitive standard.


I haven’t given any consideration to what methods pass or fail the 
Majority Rule Criterion, but:


Plurality, Approval, -1,0,1 are among the methods that pass.



You are repeating your old trick of claiming that methods like Approval and 
FPP meet criteria just because they use barbarically

restrictive ballots.


No trick. They do pass. But, if you'd take your head out of your ass, you'd 
notice that I said that I won't be using the Majority Rule Criterion. I in 
no way implied that Pluralty and Approval have merit because of passing 
Majority Rule. You proposed it as a criterion (yes, by a different name) and 
I merely stated some methods that pass, without saying that it means that 
they have merit.


But you're repeating your old trick of being vague. You don't specify any 
other instances of my claiming that methods like FPP & Approval meet 
criteria because they use barbarically restrictive ballots.


If a method meets a criterion, and it's a desirable criterion, then _why_ 
the method meets that criterion is irrelevant, with regard to the statement 
that the method meets the criterion, and the benefit of meeting that 
criterion. The criterion's benefits are available to voters using that 
method if it meets the critrerion. Does Approval meet desirable criteria 
because of its simplicity? Sure.



"Barbarically restrictive" is a meaningless expression, except as an 
expression of strong emotion.
You could complain about Approval "taking away" the expressiveness that 
ranking gives, if you could show that ranking is necessary and fundamental. 
Fundamental? There isn't even any agreement about how rankings are most 
fairly counted. Some fundamental standard for that is.


Rankings can be useful, depending on how they're counted. But it's

[EM] Chris: Approval

[Michael Ossipoff]

I'd said:

Obviously majority rule is violated by an outcome that is contrary to what 
a majority have voted that they want. For instance, if a majority vote B 
over A, then we can assume that, if A or B wins, they vote that it be B.


Chris says:

That is reasonable, and granted for the sake of argument. That implies that 
you agree with Kevin Venzke that Minimal Defense(MD) must be met


It does?? I don't agree with Keviln Venzke that Minimal Defense (MD) must be 
met.


We've discussed this before. I have never advocated Minimal Defense.It's 
completely different from SDSC, on which it's based.


But I don’t even say that SDSC must be met. Approval doesn’t meet SDSC. I do 
say that there’s no point proposing a rank method without SFC and SDSC.


Chris continues:

no-matter-what, but while I think MD compliance can be a positive for an 
otherwise bad method I think the best methods can do without it.


Maybe, but if you do without SFC & SDSC, you're doing without the strategy 
guarantees that justify using rank balloting.




49: A
24: B
27: C|B

MD says "not A", but A is the only candidate in the Definite Majority set. 
(C knocks out B, and A knocks out C).


Ah well, that settles it, if the definite majority set says so. :-)

A majority say that, if it's B or A, it should be B. That means don't elect 
A. A is the only candidate with a majority against him.





[after a discussion of what majority rule means for single-winner outcoms]

That opens up the question of how best to measure the strength of pairwise 
defeats. Alternative algorithms for DMC are Beatpath(Total Approval),
River(TA), Ranked Pairs(TA) which all measure the strength of a pairwise 
defeat by the approval score of the pairwise winner.


Fine, measure defeat-strength that way if it results in a guarantee that's 
important to you.


DAMC measures strength in that way, but looks only at majority defeats, and 
does alright. But TA by itself won't do nearly as well.


At least in the "three candidates in the top cycle" situation, an 
alternative algorithm for ASM is Approval Margins that uses one of 
River,BP,RP
and measures pairwise defeat strengths by the difference between the 
approval scores of the two candidates. Both DMC and ASM meet the

Definite Majority criterion.


No doubt that criterion may be important to you.

[After an example]

Here {A} is not just the Definite Majority set but also the "Definite 
Absolute Majority" set


No shit!  Again, defining those sets doesn’t make them official 
standard.
If you want to say that they’re important, then you need to tell exactly 
why. Just citing them like some kind of authority doesn’t mean anything.



(which doesn't conflict with MD),
so I can't see how anyone can credibly claim that electing A here flouts 
"majority rule".


I reply:

Forgive me for being unfashionable, but a majority have indicated that if 
it's B or A, it should be B.
That B>A majority defeat isn't nullified by being in a cycle of defeats at 
least equally strong.


Yes, you or someone have made up a "definilte majority set" and a "definite 
absolute majority set", but you must understand that that does not mean that 
they automatically become the definitive standard.


I haven’t given any consideration to what methods pass or fail the 
Majority Rule Criterion, but:


Plurality, Approval, -1,0,1 are among the methods that pass.



You are repeating your old trick of claiming that methods like Approval and 
FPP meet criteria just because they use barbarically

restrictive ballots.


No trick. They do pass. But, if you'd take your head out of your ass, you'd 
notice that I said that I won't be using the Majority Rule Criterion. I in 
no way implied that Pluralty and Approval have merit because of passing 
Majority Rule. You proposed it as a criterion (yes, by a different name) and 
I merely stated some methods that pass, without saying that it means that 
they have merit.


But you're repeating your old trick of being vague. You don't specify any 
other instances of my claiming that methods like FPP & Approval meet 
criteria because they use barbarically restrictive ballots.


If a method meets a criterion, and it's a desirable criterion, then _why_ 
the method meets that criterion is irrelevant, with regard to the statement 
that the method meets the criterion, and the benefit of meeting that 
criterion. The criterion's benefits are available to voters using that 
method if it meets the critrerion. Does Approval meet desirable criteria 
because of its simplicity? Sure.



"Barbarically restrictive" is a meaningless expression, except as an 
expression of strong emotion.
You could complain about Approval "taking away" the expressiveness that 
ranking gives, if you could show that ranking is necessary and fundamental. 
Fundamental? There isn't even any agreement about how rankings are most 
fairly counted. Some fundamental standard for that is.


Rankings can be useful, depending on how they're counted. But it's 

Re: [EM] Chris: Approval

[Chris Benham]

Michael Ossipoff wrote:

Your definition of your criteria system sounds conversational and 
inexact. Could you demonstrate why Approval and 0-10 CR fail 
Condorcet's Criterion, in your system?


Aside from that, why is it ok to speak of intent, but not preference?


Speaking of preference is an ok alternative, but we don't necessarily 
want to worry about what might be 'sincere preferences'

that are voluntarily not voted.


Chris continues:

[after naming a long list of criteria met by Approval]


But it fails Majority Favourite and Majority Loser



Do you mean those criteria with your fictitious rankings? 


Yes.

I've never denied that rank methods can add advantages not available 
in Approval. I've even said that I myself would prefer a good rank 
method for our public elections, though I myself, as a voter, would be 
content with Approval. It would be a nice luxury to rank the best 
candidates, but I don't really care which one of the best candidates 
wins.


That is your individual inclination, one which is very convenient for an 
Approval advocate.



I'd said:

Obviously majority rule is violated by an outcome that is contrary 
to what a majority have voted that they want. For instance, if a 
majority vote B over A, then we can assume that, if A or B wins, 
they vote that it be B.




Chris says:

That is reasonable, and granted for the sake of argument. That 
implies that you agree with Kevin Venzke that Minimal Defense(MD) 
must be met



It does?? I don't agree with Keviln Venzke that Minimal Defense (MD) 
must be met. 


From Levin's page:



  *Minimal Defense*. /(Due to Steve Eppley.)/

/If more than half of the voters rank candidate A above candidate B, 
and don't rank candidate B above anyone, then candidate B must be 
elected with 0% probability./


Steve Eppley has defined and discussed Minimal Defense here 
 and here 
. 
Satisfaction of this criterion implies compliance with Mike Ossipoff's 
/strong defensive strategy criterion/, although the reverse is not 
necessarily true. That criterion can be found here 
.



http://nodesiege.tripod.com/elections/

It does?? I don't agree with Keviln Venzke that Minimal Defense (MD) 
must be met. 



I'd be interested in seeing an example of  MD failure that you agree (or 
are content) with.



Chris continues:


[Approval] is very vulnerable to disinformation campaigns



That's a vague statement that could be said of many methods, including 
some that Chris likes. 


My statement lacked details, but that doesn't make it "vague". I've 
elaborated this criticism of  Approval

a few times before.

Say in the lead-up to the election two candidates have announced that 
they will run, and accurate polling
of voters' voting intentions shows A52%, B48%. Say the media hate A, so 
others that hate A nominate
a third candidate C who is anathema to A's supporters (or at least some 
of them). Then those that hate A
set about giving C a high profile and publishing some fake polls that 
suggest that C has some chance to
win. This frightens some of the A supporters into approving B, causing A 
to win.


47: A
05: AB (disinformed timid A>B preferrers)
46: B
02: CB

Approval:  B53,   A52,  C2.

What  "methods that I like" do you have in mind as being comparably 
vulnerable to disinformation campaigns?




Sincere preferences:

40: A
29: BC
31: CB

The C voters vote C & B. The B voters vote only B. B wins by defection.

Chris, can you find a majority who is being robbed of victory here?


No, but if  21 or more of  the C voters also defect the sincere BC 
majority solid coalition is robbed of victory and

the sincere majority loser wins.

I've repeatedly asked you to show that Approval and CR pass or fail 
Condorcet's Critrerion, by your fictitious-ranking approach. You never 
did. I asked Chris. He couldn't either. 


In your example say the 'intended rankings' are
40: A
29: B>C
31: C>B

On these intended rankings, C is the CW. On arriving at the polling 
place we pretend that those who
were intending to rank B>C or C>B are surprised to find that they have 
to use 2-slot ballots, so they each
make an arbitrary choice whether to approve (consistent with their 
intended rankings)  one candidate or two.

This could result in these actual cast approval ballots:

40: A
29: B
10: CB
21: C
Approvals: A40,  B39,  C31.

A wins, failing Condorcet.  (This is the same set of cast ballots as in 
the "defection backfires because of too

many defectors" example).

Chris Benham






I



election-methods mailing list - see http://electorama.com/em for list info