[EM] A monotonic DSV method for Range

[Jameson Quinn]

I like this method a lot. I think that some kind of range-based DSV is
probably the ideal system, as long as it's not too much work for the voters
in question. (I favor Bucklin for similar reasons - it can be seen as an
unsophisticated, but extremely easy, form of DSV).

I don't have much more to say about the method. But I do have one comment on
your justification:

To see how this works, think of a voter located in issue space....
>

This explanation did help me understand the method. However, it's important
to remember that any simple (unweighted) issue space analysis, by nature,
ignores the possibility of condorcet ties, because they can't exist in
unweighted issue space. That means the task is just to choose the candidate
whose Dirchlet set includes the median voter - and there's a lot of methods
which do that, at least with honest voters. The real test of a DSV method is
how it handles Condorcet ties. Essentially, I think that the object of a DSV
should be to minimize honest voter regret about how their virtual DSV ballot
was counted - that is, minimize the pressure for a dishonest strategy. You
can define regret variously, I'd define it to include a product of how
dishonest/risky the voters' better strategy would have been, and the utility
benefit they would have gotten. Note that both of these numbers are
definite, not probabilistic - there is a definite winner now, and there
would be a definite winner for any cabal strategy. I don't really understand
how this system would react to a Condorcet tie - it seems it would depend
all-too-much on whether one of the top candidate's first choice votes were
minimized by the shadow of a near-clone who was not part of the Condorcet
tie.



>
> Note that our new method MPASRV automatically respects top and bottom
> ratings,
> so voters who think they have a better strategy can control their own
> approvals
> and disapprovals.
>
>
Well, it's better than the alternative, but I wouldn't exactly crow about
this. The aim of a DSV is to minimize the need for strategy and thus
minimize its use; the fact that a system allows strategy just falls out of
some combination of Arrow's criteria passed.

JQ
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