[EM] Some brief campaign argument

[Richard Moore]

LAYTON Craig wrote:

> However, it isn't necessarily true that Approval is simpler to
> understand or
> to vote.  Sure, the instructions are simple (vote for as many
> candidates as
> you like), but it isn't easy for voters to understand how they should
> vote -
> for how many candidates, what's the best strategy, how should I be
> using the
> polling information etc.  I would have trouble explaining to someone
> how
> they should be voting in approval (beyond "just vote for the
> candidates you
> like").
>
Well, that's Approval 101: "just vote for the candidates you like." If
everybody
did that, then the winner would simply be the candidate liked by the
most voters.
Not exactly SU maximization, but still about as good a mandate as can be
hoped
for. Since SU is only a theoretical standard (meaning that it can't be
measured
practically in a real-world situation), suppose we define "voter
satisfaction" as
a binary parameter: either a voter is satisfied with the result or he
isn't. Then
in that case, voters using Approval 101 strategy will be driving the
result to
maximum voter satisfaction. Most voters will be satisfied to see any
candidate
they like get elected (I know I would).

>   In Ranked Pairs, for instance, it is a simple matter.  Put your
> favourite first, and keep going - stop at any time if you get sick of
> it.
> Of course it won't be the best strategy 100% of the time, but it is
> close
> enough, certainly much closer than any similarly simple advice for an
> approval election.
>
How is that simpler than Approval 101? Not only do I have to decide
which
candidates I like (which is easy), I have to decide which ones I like
best. Sometimes
that's easy, too, but not always. If I like Candidate X's fiscal policy
but like
Candidate Y's social policy, which one do I rank first?

> There is also the potential for mass dissatisfaction from voters who
> don't
> use the correct strategy, say in a close three way contest where a
> significant chunk of voters have a sincere preference A>B>C, Approval
> vote
> AB, but an election result where B beats A by a handfull of votes.  If
> it is
> clear that A would have won in a pairwise contest between the two (and
> the
> three),
>
But we know from Don Davison's misadventures that trying to estimate one

method's results from another's outcome is not productive. How will it
be clear
that A would have won in pairwise contests? From polling? But if A was
preferred
to B and C in a pre-election poll why would the A voters have included a
B vote?
And if A was not preferred in the pre-election poll but is in a
post-election poll,
are we supposed to blame the method for a fickle-minded public?

> Approval voting will become unpopular very quickly, further
> diminishing its claims of being the best SU voting system.
>
If people are to be dissatisfied with the method whenever their
particular hoped-for
outcomes aren't achieved, then we will always be looking for a "better"
method.

>   It is much more
> likely in Approval that your vote will be irrelevant, by not
> expressing a
> preference between the frontrunners.  This is much worse for utility
> than
> very occasionally choosing a better candidate.
>
If A and B are front-runners, then I'm going to express a preference
between them.
The only time I wouldn't, is if they are very close together in utility
and there is
a lower-utility candidate who is also a strong contender. And in that
case, because
they are close in utility, the loss of utility if my second-favorite
between A and B
wins is not that great, so the impact on SU is much less than you
indicate.

Richard