[EM] Cumulative Vote equivalence to Plurality

[Bart Ingles]

Forest Simmons wrote:
> 
> Someone (Kevin or Bart or both) recently reminded us that the usual
> version of Cumulative Voting is strategically equivalent to Plurality.
> 
> However the recent proposal allowing both positive and negative votes with
> the sum of absolute values limited, is different: it turns out to be
> strategically equivalent to a method that (like plurality) allows only one
> mark, but that mark can be either positive or negative, i.e. you can vote
> for a candidate or against a candidate, but not both.

Ahh, I see that now.  I think someone had pointed this out earlier, but
I wasn't following closely enough at the time.

In that case, given the sincere ratings of:
A(1.0) > B(.99) > C(.98) > D(.97) > E(0)

my IRNR ballot would be something equivalent like:
A(0) > B(-.001) > C(-.000001) > D(-.000000001) > E(-1.0)

The idea is the same, to choose values which keep the bulk if my voting
power focused on a single choice regardless of elimination order.

So ratings still aren't necessary for optimal strategy; you could just
rank the candidates but allow the value of each vote to be positive or
negative.  Thus:
E(neg) > A(pos) > B(pos) > C(pos) > D(don't care)

I concede that this method may be an improvement over IRV (which isn't
saying much), but probably suffers from most or all of the same
theoretical defects.

Bart