[EM] Approval Voting vs Instant Runoff Voting:

[Bart Ingles]

LAYTON Craig wrote:
> 
> I'm not necessarily looking for a mathematical solution.  The point is that,
> even given a significant amount of information on which to base one's vote,
> it is still difficult to divine how to vote in approval.  So far, two
> people, both highly intelligent and with a thorough understanding of voting
> systems, have decided to vote in two separate ways, given the same
> information, preferences and expected utility outcomes.  I suspect the rest
> of the list would be similarly divided, if not the populace as a whole.

This may have been a result of differing estimates of the likelihood of
winning (or of a draw) among the candidates.  At least in my case, I
overlooked the fact that the favored candidate had an extremely slim
chance of winning.


> If people, given exactly the same utilities, cast totally different approval
> ballots, then I don't see how Approval can maximise voter utility in any
> even handed manner.  Any utility (in a broader sense) advantage Approval has
> over Condorcet is more than countenanced by the fact that it doesn't give
> votes equal power.  This is also true, of course, if someone votes
> insincerely (and non-strategically) or truncates their vote in a Condorcet
> election, but this inequality is the fault of the voter.  The inequality in
> Approval is the fault of the voting system.

Maximizing utility isn't the only consideration, or even necessarily a
major consideration (at least to me).  More important is the ability to
reject candidates with extremely low social utility.  When the choice is
between candidates with moderately high social utility, then I would
tend to look at other considerations, such as a majoritarian outcome.