[EM] Approval Strategy

fsimmons at pcc.edu fsimmons at pcc.edu
Sat Dec 24 12:53:28 PST 2011


> From: MIKE OSSIPOFF 
> To: 
> Subject: [EM] Approval strategy
> Message-ID: 
> Content-Type: text/plain; charset="iso-8859-1"
> 
> 
> Forest--
> 
> You wrote:
> 
> Also, going back to what you metioned before about the value of 
> showing support for losers that you like 
> better than the winner (given they have the chance of the 
> proverbial snowflake), I think that this is perhaps 
> the main rationale for extending approval all of the way down to 
> the candidate most likely to win (and 
> include that candidate only if the runner up is below it). 
> [That's another way to state strategy A.]
> 
> [endquote]
> 
> Ok, sure, I understand the justification. To show support for 
> candidates better than the frontrunner
> you're voting for, and who are unlikely to be a serious rival to 
> hir, 
> one could approve all of the inbetween candidates better
> than the frontrunner that one approves.
> 
> It comes down to a question of whether you want to show that 
> support, or whether you want to do _strictly_
> instrumental voting, where you assume that even the non-
> frontrunner inbetween candidates have a finite
> chance of being a rival to a frontrunner.
> 
> So I don't disagree with strategy A--It's merely a question of 
> whether one wants to deal with the
> inbetween candidates expressively or strictly instrumentally.
> 
> 
> I think that the honest Approval strategy is a fascinating 
> finding--Effective score-voting in Approval,
> without randomization. That means that score voting is 
> especially easily available in Approval. So,
> having proposed Score-Voting, one could then point out that it 
> can be easily achieved with the more modestly-
> demanding Approval balloting.
> 
> As for myself, in Score-Voting, I'd probably use non-extreme 
> points assignments only in two instances:
> 
> 1. The excellent diplomatic ABE solution that you suggested for 
> Score-Voting

Excellent except that satisfaction of the FBC is in doubt.

> 
> 2. When a candidate is about as bad as a candidate can be and 
> still be barely acceptable,
> ...and so I feel that it's questionable whether s/he deserves a 
> full approval.
> 
> In an Approval election, I'd randomize in those 
> instances....unless honest Approval would work there too. 
> 
> Honest Approval stratgegy is probably only for someone who wants 
> to do score voting for all the
> candidates. Or maybe not. Maybe some intended maximum and 
> minimum ratings wouldn't interfere with
> voting an honest Approval ballot. Then, honest Approval voting 
> would avoid for me, too, the task
> of randomizing.

The main difficulty with honest approval voting is that when there are three candidates generally one will 
be rated 100%, one zero, and the other somewhere in between, so the expected number of approvals 
(as the sum of the ratings) will be somewhere between one and two.  On this basis you know that you 
should approve at least one candidate (which is already obvious) but nor more than two (which is already 
obvious as well).  So in the very practical case of three candidates the method still requires something 
like randomization or gut feeling to decide whether or not to approve the middle candidate.

> 
> By the way, of course your Score-Voting ABE solution only works 
> if it's known how many votes A
> and B, combined, are going to get. 

This is true, so the method requires knowledge when the defection strategy is likely.  But the more 
likely the knowledge is sufficient to make defection strategy possible, the more likely there is enough 
knowledge for the other faction to make it risky.

But it is better to have a method such that zero info strategy by the naive betrayed faction will 
automatically defend against defection on the part of the cunning faction..

> In a first election by 
> Approval or Score, that might not be known.
> Then, maybe an A voter might have to just hold hir nose and 
> fully approve B, to keep C from wining.
> 
> Later, when the numbers are more predictable, the A voters could 
> use your Score/Approval ABE solution.
> 
> But that shows a big advantage of MMT, GMAT, MGMAT, MTAOC and 
> MMABucklin
> Mike Ossipoff
> 
> 



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