[EM] Combined elections

Raph Frank raphfrk at gmail.com
Fri Dec 4 02:12:02 PST 2009

```On Fri, Dec 4, 2009 at 12:12 AM, Juho <juho4880 at yahoo.co.uk> wrote:
> 27: A=1 B=0 C=0 D=2
> 26: A=0 B=2 C=1 D=0
> 25: A=2 B=0 C=1 D=0
> 22: A=0 B=1 C=0 D=2
>
> A would win the first Condorcet election (or Plurality or whatever common
> single-winner method). C would win the second Condorcet election.
>
> Let's then combine these elections into one election in which the outcome
> alternatives (sets of winners of the two component elections) will be AC,
> AD, BC and BD. We can sum up the preferences so that each voter is
> considered to prefer outcome x to outcome y if the sum of his/her ratings of
> the candidates is higher in outcome x than in y. The first 27 voters are
> thus considered to prefer outcome AD (1+2 points) to BD (0+2) and AC (1+0)
> and BD (0+0).
>
> 27: AC=1 AD=3 BC=0 BD=2
> 26: AC=1 AD=0 BC=3 BD=2
> 25: AC=3 AD=2 BC=1 BD=0
> 22: AC=0 AD=2 BC=1 BD=3
>
> Based on the resulting preference orders we will then use some Condorcet
> method (=some good single winner method) to determine the winning outcome.

So, for each voter, you use the ratings to create a ranked list of all
combinations of the options, and then pick the condorcet winner?

The effect is to allow voters to trade-off one candidate against the other.

This is similar to the effect of coalition negotiations.

A&B could be one policy question and C&D could be another.

A party could very easily accept an undesired decision in the AvB
direction in order to get what it wants in the CvD axis.

With lots of options, you could just do a random search method.  Pick
a random result and compare it to the winner so far.  If the majority
prefer it, then that becomes the provisional winner.  You could also
allow people to submit their own options.

There might be some issues with having control of the questions being
put.  Adding a "poison pill" as an option could cause problems.  Maybe
options which have the support of 75% of the population (or opposition
of 75% of the population) are excluded.

I think it might have some strategy problems.

```