# [Election-Methods] elect the compromise

Jobst Heitzig heitzig-j at web.de
Wed Sep 5 23:03:43 PDT 2007

```Dear Forest!

Binding agreements will not solve the problem completely I think. Assume
the situation is this, with 4 candidates A,B,C,D of which 3 (A,B,D) have
each received 1/3 of the vote, and with the following preferences over
lotteries:

A: A 100, C 80, BD 0
B: B 100, C 80, AB 0
D: D 100, C 80, AB 0
(The number 80 in the first row means A prefers getting C for certain to
getting A with 80% and B or D with 20% probability.)

Now if one of the three bluffs by claiming not to consider C a good
compromise, the other two still gain by signing an agreement to transfer
their probability share to C. Hence each of the three has an incentive
to bluff if she can hope the other two will probably sign the agreement
anyway.

The only solution seems to be that at least one of them announces that
she won't sign an agreement with only one other but only with both
others. But such an announcement would only be credible if that
candidate would at the same time represent her rating for the compromise
as something between 34 and 49 instead of 80.

In any case, it seems that also with binding agreements it depends on
what information the candidates have about the other's preferences...

Yours, Jobst

Forest W Simmons schrieb:
> Jobst,
>
> I'm not sure how to define "rational" in this context, either.
>
> As for the prisoner's dilemma problem, I wonder if the possibility of
> "defection" could be eliminated by having trading parties sit down and
> sign binding agreements during formal trading.
>
> My Best,
>
> Forest
>
>
> Jobst Heitzig wrote:
>
>
>
>> Dear Forest,
>>
>>
>>> Perhaps candidates should be required to publish their range ballots
>>> before the election, and their "trading" of assets should be required
>>> to be "rational" relative to these announced ratings?
>>>
>>>
>> I had this idea, too. But upon closer inspection, it is not quite easy
>> to define what in this case "rational" means, since in this form of
>> trading there easily arise situations similar to the prisoner's dilemma
>> and situations in which "bluffing" could work...
>>
>> Yours, Jobst
>>
>>
>>> Or perhaps, a randomly chose jury of candidate X supporters should
>>>
> have
>
>>> some say in the candidate X proxy decisions?
>>>
>>> Forest
>>>
>>>
>>>
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> info
>
>>>
>>>
>>
>>
>
>
>

```