[EM] Cabal equilibria in voting

[Peter de Blanc]

Hi,

I've been doing some analysis of strategic voting - specifically, 
looking for equilibrium strategies. Nash equilibria are of course not 
very useful for elections, because almost anything is a Nash 
equilibrium. So I've defined a less inclusive type of equilibrium called 
a cabal equilibrium.

The very short version of the result is that most popular voting methods 
(plurality, approval, Condorcet, IRV) have a cabal equilibrium iff 
there's a Condorcet winner, and a cabal equilibrium always elects a 
Condorcet winner.

I have a longer post about this on my blog, here: 
http://www.spaceandgames.com/?p=106

The post also links to some of my earlier work on the same topic.

  - Peter de Blanc