[EM] Approval Voting

[Kristofer Munsterhjelm]

On 05/06/2013 11:21 PM, Jonathan Denn wrote:
> In these "likely" scenarios, and assuming there is no electoral
> college, doesn't a runoff of the top two seem the best method until
> someone gets a majority?

It would solve that problem, but the problem can be reintroduced if each
party gets greedy.

Say each party thinks like this: "We can get our partisan voters to vote 
for only our own candidates. If we'd win an ordinary Approval with a 
single candidate, then by fielding n candidates, we can win a top-n 
runoff". So they each field two clones, and you get a result like:

H1: 34%
H2: 34%
D1: 33%
D2: 33%
R1: 33%
R2: 33%

now H1 and H2 go to the runoff.

For Approval, it'd be better to pick the challenger as the candidate 
who's approved by most people who didn't approve of the winner. Then H1 
and a non-H candidate go to the runoff, and the non-H candidate wins.

There may be more sophisticated methods that solve that problem as well. 
My "pick the candidate who's approved by most who didn't approve of the 
winner" was just something I thought of as I wrote this, and it may (for 
all I know) have strange strategy incentives.