[EM] reply to venzke - range "random skewing" effect is not a problem

[Juho]

On Mar 13, 2007, at 21:20 , Abd ul-Rahman Lomax wrote:

> At 03:00 AM 3/13/2007, Juho wrote:
>> I guess you, as a Range expert, pretty well know what the anticipated
>> problematic scenarios are. Problems may arise e.g. when opinion polls
>> tell that Democrats would get only 49% of the votes (against 51% of
>> the Republicans) and therefore their supporters decide to put some
>> additional weight in their votes and vote strategically in Approval
>> style. This would make the Democrats win.
>
> Why? I really think this should be realized: I expect, at least  
> initially, major party supporters to vote under Approval exactly  
> the same as they currently vote under Plurality. Almost all will  
> bullet vote.

This sounds to me like you are close to the third style of using /  
seeing the Range method (that I defined in my mail). => "3) accept  
the elections to turn into Approval like elections as a result of  
widespread Approval style voting". With two major parties Approval  
and bullet voting are about the same thing.

One could thus use the Range method in different ways: 1) use it in
non-competitive elections, 2) allow strategic/exaggerating/"sincerely
strong opinion" voters to have more say and make their favourite win
with improved likelihood, 3) accept the elections to turn into
Approval like elections as a result of widespread Approval style voting.

> I don't know how many times this nonsense has been repeated. "Range  
> becomes Approval." No, Range will *never* become Approval unless  
> you can somehow get all the voters to not express intermediate  
> ratings.

This however confused me. In the beginning of the mail you assumed  
that almost all will bullet vote (which I interpreted to be in line  
with Approval). But here the interpretation is maybe that a  
considerable part of the voters will vote with intermediate ratings.  
For me majority voting in Approval style and some voting with  
intermediate rankings means "close to Approval".

Btw, note that also in Approval voters are allowed to cast weak  
votes, that is empty votes. Ratings based methods are just more fine  
grained.

>> The achieved results of
>> Approval voting are not very bad in terms of achieved social utility.
>> The worst scenarios are ones where some parties/groupings vote in
>> Approval style while others do not. In these cases it seems obvious
>> that the social utility would not be good.
>
> It is not obvious at all.

I referred to cases like 35:D=100,R=90 65:R=100,D=90 where the social  
utility of R can be claimed to be higher than the utility of D. If  
strategic voting is used only by D supporters (35:D=100,R=0), then D  
wins and achieved utility is considerably worse than with sincere votes.

Juho



		
___________________________________________________________ 
The all-new Yahoo! Mail goes wherever you go - free your email address from your Internet provider. http://uk.docs.yahoo.com/nowyoucan.html