[EM] STAR Voting Variations

[Daniel Carrera]

On Mon, Jul 12, 2021 at 8:41 PM Susan Simmons <suzerainsimmons at outlook.com>
wrote:

> ... continuing ...
>
> Here's another small tweak to create a similar, but much improved method
> ... let's call this tweak of STAR, "CHAMP."
>
> STAR elects the pairwise winner between the score winner X and the
> candidate Y  who is the score winner among the other candidates (besides X).
>
> CHAMP elects the pairwise winner between the score winner X and the
> candidate Z who is CHAMP winner among the other candidates (besides X).
>

It took me a while to figure out what you were saying. So... a recursive
definition of CHAMP... Btw, what does CHAMP stand for (if anything)? Let me
see if I understand. If I wanted to compute the CHAMP winner I would:

1) Sort the candidates by score.
2) Pick the pairwise winner "X" between the bottom two candidates.
3) Pick the pairwise winner between "X" and the next candidate up.
4) Repeat.

So CHAMP Is kind of like BTR-STV but you are sorting by score instead of
first-choice votes? CHAMP = BTR-Score ? Or have I completely misunderstood?



> It turns out that this description of CHAMP is just a particularly compact
> [and elegant, in the eyes of software engineers] reformulation of
> Sequential Pairwise Elimination (SPE) applied to the "agenda" of candidates
> listed from least to greatest scores.
>
> SPE is a highly respected method that has been used in many kinds of
> deliberative bodies for centuries, and recommended by "Robert's Rules of
> Order" for choosing from among more than two options ... two-at-a time from
> an agenda with the least promising agenda items listed first. In the CHAMP
> context "least promising" means lowest score.
>
> CHAMP is clone proof, monotonic, and Condorcet compliant ... what simpler
> method has this much going for it?
>

A recursive method will be tough for most people. I studied Lisp and it was
a bit of a curve ball for me. I think an SPE definition might be easier to
follow even if it is mathematically inelegant.

If I was trying to sell this to the STAR team, I would tell them that they
can even keep the same name they have.

STAR = Score Then Automatic Runoff

There is nothing in that name that requires only one runoff. You could
repurpose the name to mean that you Score candidates and then run N runoffs
from the bottom up. Boom! Now you've turned STAR into a clone proof,
monotonic, Condorcet method and hopefully created a method that fans of
Score and fans of Condorcet can both get behind.

Am I right to think that your method, and any other BTR-* method is also
Smith-efficient?

Cheers,
Daniel
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