[EM] Is strategic voting a bad thing, really?

[Adam Tarr]

Bill Clark wrote:

>Recently I've come to question the accepted wisdom that strategic voting
>is a bad thing that should be minimized.

I prefer to think of it as minimizing the disadvantage associated with 
sincere voting.

The issue is that many people are only going to be willing to vote a 
sincere ballot - or perhaps a ballot that leaves some candidates off the 
bottom, but is sincere aside from that.  Current voting patterns in 
plurality suggest this.

>Are there cases where the winner according to strategically cast ballots
>is a better choice than the winner according to sincere ballots?  IRV
>instantly comes to mind, since it seems to suffer from a multitude of
>problems even when voters cast their ballots sincerely (so much so, that
>I'm led to wonder if widespread strategic voting might actually *improve*
>the results in some instances.)  What about other systems?

I think that, in general, strategic voting pulls the election results in 
the direction of the Condorcet winner, or barring that, the Smith set.

>What work has been done in this area, which might serve as a starting
>point for further research?

It's been shown that, using certain simple strategies, repeated balloting 
in approval election will lead to the electorate nearly always settling on 
the CW, except in some very rare cases where there's a cycle of preference 
among three lower choices, and the voters get stuck in that rut.  There's 
always a stable equilibrium involving the CW if one exists.