[EM] Strategic polls in Approval

[Juho]

On Dec 30, 2006, at 18:37 , Abd ul-Rahman Lomax wrote:

> The particular vulnerability alleged here is actually applicable to  
> *all* election systems, it happens to be here stated in a specific  
> way that could make it appear that AV is more vulnerable than, say,  
> IRV or IRRV.

The interesting part is that the regular optimal strategy  
recommendations for Approval and opinion polls can be used to change  
the way individual voters will vote (if voters use the recommended  
strategies, if only some parties use this strategy etc.).

> This is an election where there is something close to a three-way  
> tie. That's rare, for starters.

This strategy requires at least three candidates that can be claimed  
to be leading candidates.

In two-party countries having three candidates of about equal  
strength would be exceptional. Im multi-party countries or if parties  
have more than one candidate that is not exceptional.

> I don't think the poll would have much effect. For this strategy to  
> work at all, the election has to be close, there must really be  
> some doubt about which of the three candidates will actually turn  
> out to be in third place. So voters will consider that.

In the example it was ok if voters were uncertain of which opinion  
polls are reliable. The plotters were happy with the confusion (as  
long as they could avoid having polls where A was not among the  
leading candidates).

The strategy works (partially) even if only some voters get fooled.  
If A and B were close to equal then already a small change may bring  
victory to A.

> Where there are three frontrunners, this strategy does not exactly  
> apply. That's the situation proposed. There are really no  
> frontrunners in this race.

In the example the first (correct) poll showed that A and B had more  
support than C (but only so much that the A supporters could claim  
that also C could be a lead candidate).

>
> The protection would be a requirement that the winner obtain  
> majority approval. Many elections require this. With that  
> requirement in place, a different strategy is proposed that is much  
> simpler and not vulnerable to this polling deception, because it  
> does not involve determining the frontrunner.
>
> For each candidate, make an independent determination: would you  
> prefer the office to remain vacant or for this person to be  
> elected? If you'd prefer the office to remain vacant, don't vote  
> for the candidate. If you would prefer the candidate to be elected,  
> vote yes. The winner, with approval, then, is the candidate most  
> widely acceptable, or there is no winner.
>
> I've learned a great deal by thinking of the deliberative process  
> used under Roberts Rules as the basic *deliberative* election  
> method: sequential nomination and vote. Someone moves that A be  
> elected as the officer. If the motion is seconded, it is then open  
> to debate and amendment. If I move that B be substituted in the  
> motion for A, and my amendment is seconded, *this* can then be  
> debated, and, presumably, will ultimately come to a vote. The vote  
> essentially determines if the members prefer B to A or not. If they  
> prefer B to A, then the amendment will pass. This process continues  
> until all reasonable nominations have been made and accepted or  
> rejected. At some point, debate is closed, typically by a two- 
> thirds vote, and the main motion proceeds to vote. If it passes, we  
> have elected an officer. If not, the post remains vacant or is  
> otherwise filled temporarily according to the emergency rules that  
> apply when a post becomes vacant for some reaso
>
> *This is a Condorcet-compatible method,* but what may be easily  
> missed is that preferences, in a deliberative process, are not  
> fixed things. This is the difference between deliberative and  
> aggregative process. Aggregative process, i.e., voting, simply  
> attempts to take a snapshot of preferences, and possibly preference  
> strengths as with, for example, Range, at one point in time. It  
> includes preferences that would change if exposed to debate. It  
> includes preferences that would shift if people knew what others  
> preferred.
>
> Because of our continual exposure to preference systems, and a lack  
> of exposure to Approval and Range methods, we tend to think of  
> elections as a contest, with voters being opposed to each other if  
> they prefer different candidates. But in real organizations, where  
> people care about each other and about the health of the  
> organization, it can matter very much that a candidate is not  
> merely the preference of a majority, but also that the candidate is  
> more widely *acceptable* than that. And I have seen voting in small  
> groups where the majority set aside its preference in order to make  
> a decision that was actually approved by consensus.
>
> Range methods can collapse this process into a single vote, but the  
> give-and-take that is typical of deliberative process is missing.  
> Range is still an aggregative method and thus is relatively  
> inflexible, compared to full deliberative process.
>
> I think we need to understand that we don't use full deliberative  
> process, not because the results aren't superior (they would be)  
> but because full deliberative process is very time-consuming and,  
> as the group size increases, becomes increasingly so. The answer to  
> this, aside from using elected representatives, as in the U.S.  
> Electoral College as designed, not as actually used, is Delegable  
> Proxy or Asset Voting. This allows the group deliberating to be  
> boiled down to a manageable size.
>
> I think the Electoral College was conceived to function in this  
> way. However, the Constitutional Convention could not agree on how  
> electors were to be chosen, so they left it to the states, a  
> loophole that political parties soon discovered and used to full  
> effect. Leaving it to the states meant leaving it, aside from the  
> states amending their constitutions to prevent it, to the  
> legislatures. And the legislatures could make decisions about  
> electors by majority vote. So the controlling party in each state  
> could simply award all the electors of the state to their own  
> party. And they did.
>
> And this has never really been fixed.
>
> Now, as to the polling fraud strategy. If you can fool voters about  
> a poll, seriously, not just a few points this way or that, you can  
> fool them about other things as well, you can influence them to  
> vote as you desire by deceiving them about issues and facts. This  
> is a general hazard to which all aggregative methods involving the  
> general public are vulnerable.
>
> And poll results are *not* essential for good Approval Voting. I  
> stated an alternative strategy that could easily be used in a three- 
> way race, and I suggest it is an appropriate one there.
>
> When there are two front-runners, not three, voters can be  
> reasonably certain that one of them will win, and, thus, the  
> realpolitik strategy of accepting one of them is prudent, even if  
> you don't approve of either of them and would prefer to leave the  
> office vacant. That is, if you can be reasonably confident that  
> there *will* be a winner from among those two, then you will  
> attempt to influence that choice. If not, you will not use that  
> strategy. Your favorite does have a shot at winning, and so do both  
> of the others. So you will vote for your favorite and then whether  
> or not you vote for either of the others depends on whether or not  
> you will find your favorite among them acceptable if they are elected.
>
> I think this "Yes/No" strategy is an important one and should be  
> mentioned in descriptions of Approval Voting. It is actually the  
> foundation strategy.... the choice between frontrunners, if neither  
> is your favorite, is a detail arising under certain conditions  
> only. Zero-knowledge, you would vote the Yes/No strategy,  
> preferring the office to remain vacant to electing a No candidate.
>
>
>
>
>


	
	
		
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