[EM] Generalizing "manipulability"

[Jonathan Lundell]

On Jan 17, 2009, at 4:31 PM, Juho Laatu wrote:

> The mail contained quite good
> definitions.
>
> I didn't however agree with the
> referenced part below. I think "sincere"
> and "zero-knowledge best strategic"
> ballot need not be the same. For example
> in Range(0,99) my sincere ballot could
> be A=50 B=51 but my best strategic vote
> would be A=0 B=99. Also other methods
> may have similarly small differences
> between "sincere" and "zero-knowledge
> best strategic" ballots.

My argument is that the Range values (as well as the Approval cutoff  
point) have meaning only within the method. We know from your example  
how you rank A vs B, but the actual values are uninterpreted except  
within the count.

The term "sincere" is metaphorical at best, even with linear ballots.  
What I'm arguing is that that metaphor breaks down with non-linear  
methods, and the appropriate generalization/abstraction of a sincere  
ballot is a zero-knowledge ballot.

>
>
> Juho
>
>
> --- On Sun, 18/1/09, Jonathan Lundell <jlundell at pobox.com> wrote:
>
>> The generalization of a "sincere" ballot then
>> becomes the zero-knowledge (of other voters' behavior)
>> ballot, although we might still want to talk about a
>> "sincere ordering" (that is, the sincere linear
>> ballot) in trying to determine a "best possible"
>> outcome.