[EM] IMHO, IRV superior to approval

[Kevin Venzke]

Chris,

Feeling the need to disagree...

 --- Chris Benham <chrisbenham at bigpond.com> a écrit : > Stephane,
> I  also rate IRV  above Approval, for many reasons. For a method to be 
> acceptable to me, it must meet  Majority for solid coalitions (Woodall 
> calls "Majority" and  others call  "Mutual Majority")  and  Clone 
> Independence(Woodall's  Clone-winner and Clone-loser
> criteria). Common-sense, Mike O. and I  agree that  Approval fails Clone 
> Independence.  Some may sneer, but these criteria are
> easy to meet; and failing them allows  all sorts of  unfairness and 
> absurdity.

Mutual Majority and Clone Independence are easy to meet, but they also don't
guarantee much.  Clones, and a majority-strength coalition for a set of more
than one candidate, hardly ever exist.  I would love to see a real IRV election
where they did.

I am more interested in "half-clones," since they seem more likely.  By "half-clones"
I mean a set of candidates whose support only partially overlaps.  I believe
that Approval deals better with half-clones than IRV does.  This is because IRV
forces the voter to decide which candidate he'll rank where, and if the voter is
wrong, the result may be the election of the voter's least favorite.

This is a tired scenario, but consider this while thinking of "half-clones":
40 A
35 C>B
25 B

I call {BC} a half-clone set.  In Approval the C>B voters can vote CB and still get
B to win, and this doesn't involve any insincerity.  In IRV those voters should put
C below B in order to avoid electing A.  Not only does IRV encourage insincere
voting here, but the fact that it does so will be a strong incentive for C not to
enter the race at all.

So the biggest reason I prefer Approval to IRV is IRV's nomination disincentives.

> I  like methods that have no zero- information strategy, 

I think you are saying Approval has strategy, even with zero-info, because sincere
voting is undefined for Approval.

> and  doesn't 
> reward  indecisive voters by giving them extra clout.  If  voter  A
> ranks candidate X last,  and  because of  prejudice, ignorance and 
> stupidity has no ranking of the other candidates; and voter B ranks
> candidate Y last but also strictly ranks all the other candidates; then 
> both candidates X and Y should have the same probabilty of being
> elected.

I still think "probability of being elected" is undefined here.  Usually that
term is used when there is a tie...

> "No Zero-Information Strategy"  also implies that Later-no-harm and 
>  Later-no-help should be in balance. That is, that the chances of
> harming or helping an already ranked candidate by ranking another below, 
> should be the same.

1. Can you tell me a method besides Approval which fails "no zero-info strategy"?
Because I take it you really mean that zero-info strategy should be equivalent to
a sincere vote.
2. Can you tell me a method which fails "no zero-info strategy" where LNHarm and
LNHelp are not in balance?

> One of my fundamental standards is that a method should perform reasonably when all the voters
> vote sincerely (taking no account of how any other voters might vote). 
> A method should be able to cope with insincerity, but to perform reasonably it definitely
> shouldn't
> DEPEND on insincerity."
> 
> Isn't that enough "unfairness and absurdity"?
> 
> I agree that "defensive srategy citeria" are valuable, but the starting point should be that the
> method is, and appears to be, fair and sensible if all the voters vote sincerely.

Do you believe that IRV "is and appears to be fair and sensible if all voters vote sincerely,"
compared to Approval?  In general?

> Approval is based on the assumption that all the voters strategise, and in effect invites them
> to
> do so; because it doesn't even give voters who have a strict ranking and who want to vote
> sincerely
> a clear-cut instruction on how to do so. Instead it leaves them wondering why they should "vote
> for"
> more than one candidate, and if they should, then how many more.
> 
> Approval would be less unacceptable if the ballot instruction was at least concise and
> semi-sensible.
> Either "Check the candidates you rank in equal-first place. Barring candidtes you rate as
> unacceptable,
> check the other candidates you rate as above-average in this field", or the simpler "Of these 
> candidates, check those you rate as above average".
> But according to Approval advocates that I've been in contact with, there definitely shouldn't
> be
> "strategy advice" on the ballot paper. Oh no, there should just be the infuriatingly meaningless
> "Vote for" whichever candidates you choose.

FPP ballots already say "vote for one," not "vote for the candidate you think is best" or
even "vote for the candidate you wish to see take this office."

There shouldn't be strategy advice unless it's actually *good* advice.  But even then,
why would you want to suggest that using good strategy is part of following the ballot
instructions?  Wouldn't that make things worse, from your perspective?

If your concern is that "sincere voting" should be defined for Approval, I would prefer "Vote 
for your favorite(s)" to your suggestions.

> Another thing I hate about Approval is that elections in the US are apoltical enough as it is.In
> election campaigns, voters should be thinking about politics, and the policies and qualities of 
> the candidates.

Well, they would still think about the "qualities of the candidates."  It's alright
with me if that is *all* a voter thinks about, since I don't consider voters to be policy
experts.  If I did, I would just advocate closed-list PR.

> Approval would help get rid of that, by turning the election into a kind of
> sport between rival factions of strategising voters. Tv debates and newspaper articles could 
> be all about "what is the best Approval voting strategy?". Also of course, obsessing about 
> polls will be intensified. Maybe everytime a new poll is published, tv reporters will ask 
> Mike Ossipoff "What does this new poll mean for voters who want to maximise the effect of 
> their vote?"

That is an interesting thought.

> And of course voters who succeed in ignoring this circus and instead just concentrate on the 
> policies and qualities of the candidates, will potentially be greatly disadvantaged (much more
> than a "naive", sincere IRV voter).

Here I completely disagree.  A gut-sentiment Approval voter will probably not be far off
from his optimal way of voting.  He screws up only if he approves or disapproves both of
the strongest candidates.  In IRV he can screw up by not guessing who needed his traveling
vote when.

Kevin Venzke
stepjak at yahoo.fr



	

	
		
Yahoo! Mail : votre e-mail personnel et gratuit qui vous suit partout ! 
Créez votre Yahoo! Mail sur http://fr.benefits.yahoo.com/

Dialoguez en direct avec vos amis grâce à Yahoo! Messenger !Téléchargez Yahoo! Messenger sur http://fr.messenger.yahoo.com