[EM] Meta-criteria 9 of 9: Conclusion

[Jameson Quinn]

Finally, I come to the end of this series. To conclude, let me return to the
initial question which started me down this path: what do the values and
heuristics have to say about voting system criteria?

Utility (that is, outcome social utility) is a unique value in that we have
a single clear tool for analysis: Bayesian regret simulations. The only two
things we need are a model for voter utilities - which should have only
weak, linear effects on the performance of a given system - and a model for
voter strategy. I hope that my analysis of strategy helps us get the latter.
And meanwhile, I hope that the outstanding issues of strategy, along with
the issues of expressivity, legitimacy, and cost, can help the partisans of
Bayesian regret analysis (a group in which I weakly include myself) be
humble about the results so far.

The criteria that relate to expressivity are mainly participation,
consistency, and related criteria. There is a certain fundamental tension
between expressive freedom and outcome utility in a decisive system. Ballots
which give a large degree of decisive freedom to voters inevitably involve
strategic tradeoffs between utility and expressivity. Perhaps one way to
resolve this is to make a hybrid system, which is part election and part
nonbinding poll. The election part would strictly limit voter freedom in
order to eliminate strategic concerns; two-rank Bucklin is one possible
example of the limited freedom I'm imagining. And the poll part - probably
based on Range, for maximum freedom - would allow free expressiveness; while
it wouldn't be binding, to keep stratgic concerns from taking over, it would
certainly affect a candidate's mandate. The poll would be optional; a simple
Bucklin vote would be counted with some default assumptions about what that
means in Range terms. Maybe you could even give marginal impact to the poll
without making it too strategic. For instance, if you were building a polity
from scratch, the rule could be that a Bucklin winner is elected, and if
they're also a Range winner they get an extra year on their term; or that
the Range winner gets to appoint the attorney general; or some such marginal
importance for the poll.

The criteria that relate to legitimacy are participation; consistency; and
clone-, strategy-, and fraud- resistance criteria.

The main criterion that relates to cost is one-round decisiveness.

The heuristics relate to various criteria, but in another sense they
function as vague criteria themselves.

I'll repeat my conclusion to the long section on strategy here, too.
Strategy's biggest effects are not on outcome social utility, but on
legitimacy and expressivity. I believe that these effects are serious and
worth avoiding. Cabal strategy seems to me the best model for strategy
analysis, but if it isn't going to get hung up on all Condorcet ties being
strategic, it needs to include factors which affect the likeliness of
strategy actually being used. These factors include motivation, implied
dishonesty, and necessary participation.

Finally, for those who have read through this nearly endless treatise, thank
you for your patience. I hope that I've said enough to make it worthwhile. I
also hope that I start more than one productive discussion - productive
enough to change my mind about some aspects of what I said. My ultimate hope
is that this kind of discussion will help us have the perspective to
recognize, to design, to evaluate, and finally to begin to agree on the best
possible voting systems. The more big-picture perspective we have and share,
the more we will become an activist force with which nations must reckon.
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