[EM] Anyone got a good analysis on limitations of approval and range voting?

[Kristofer Munsterhjelm]

Warren Smith wrote:
>> It seems to me that approval and range voting eliminate most of the
> strategic opportunity in single winner elections and the marginal
> improvement of other methods is fairly small. Can anyone point me to
> analysis, preferably at a layman level, that contradicts or supports this
> assertion?
>> Or, in succinct terms, what are the strategic flaws in approval or range
> voting?
>> Thanks, Matthew Welland
> 
> --well... there is the whole rangevoting.org website...
> my more-recent papers at
> math.temple.edu/~wds/homepage/works.html
> discuss range voting including some ways it is provably better than every
> rank-order voting system for either honest or strategic voters...
> 
> --but those are not exactly "succinct"...
> 
> OK Let me try:
> 1. Range for 100% honest voters behaves better than IRV, Borda,
> Condorcet and it is pretty intuitively clear why -- strength of
> preference info used, not discarded.

There is, of course, the flipside of that property. If one wants a 
voting method where the majority wins, then Range won't work, simply 
because a minority of strong opinions can outweigh a majority of weak 
ones. You might argue that that is no bug at all (strong opinions 
*should* outweigh weak ones), but for those for which Majority 
compliance is a must-have, it should be mentioned - particularly since 
that is supposed to be one aspect of the fairness of traditional democracy.

In that sense, moving to Range (and perhaps Approval - depends on how 
you interpret it) is a more radical proposal than, for instance, moving 
to Condorcet (which passes Majority).

(And now I wonder which election method that passes Majority has the 
least Bayesian regret.)