[EM] Easy fix to Alaska's ranked-choice voting
Colin Champion
colin.champion at routemaster.app
Mon Nov 14 13:37:38 PST 2022
On 14/11/2022 03:54, Forest Simmons wrote..
> many wise things
I think Forest slightly missed my point - I was arguing that SPE could
be proposed *as an alternative* to truncation, since I surmised
(incorrectly) that truncation might have been justified by a desire to
avoid quadratic counting costs. Hence there would be no cutoff as part
of the voting procedure, and no natural concept of implicit approval. If
there is political opposition to mechanical counting, then proposing a
linear-time countable method seems to me better than either putting up
with truncation or fighting unnecessary battles.
I don't know why linear-time countability dropped out of consideration.
In 1275 Llull proposed the "league table" method now often named after
Copeland, but with one difference - he didn't suggest ranked preference
voting (after all, paper hadn't been invented then, let alone
computers). Instead he called for m(m-1)/2 pairwise subelections. In
1299, presumably recognising the unworkability of this, he proposed a
"knockout" method comprising just m-1 pairwise subelections which
amounts to SPE with an arbitrary agenda. I think this was in one of his
writings which got lost.
A little later, taking advantage of the invention of paper, Nicholas
of Cusa proposed the Borda count in conjunction with ranked preference
voting. Borda reinvented his ideas in the 18th century. Condorcet (in
his Essai) got bogged down in problems arising from cycles, and
partially extricated himself with a quadratic-time algorithm which is a
simplified ranked pairs. In his later writings he reinvented Llull's
league table method and instantly rejected it on account of its
quadratic cost. In its place he advocated what I take to be a defective
form of Bucklin's method.[1] This was adopted in Geneva and "found not
to work" (I don't know the details, but Bucklin's method is quite a
large step backwards).
Nanson carried on from Condorcet. He agreed that the quadratic cost
made Llull's league table unworkable, wasn't attracted to Bucklin's
method, and instead proposed his own. He may have been a little
optimistic in his costings, but at worst his method is m log m.
That seems to be the end of the discussion. When Black proposed his
method in the middle of the last century, voting technology was no
different than in Condorcet's day, but he doesn't seem to have worried
about the counting costs. Llull's knockout reappeared as SPE with a
pre-ranking stage to eliminate the obvious asymmetry, but since
quadratic-time pre-rankings are often assumed, counting time hasn't
always been the main consideration.
CJC
[1]. I always confuse Bucklin's method with Baldwin's. I wish the latter
was called the "Trinity College" method, since it was invented before
Baldwin's time. The Trinity College Dialectic Society was founded at
Nanson's university a few years before Nanson wrote his memoir, so its
voting method was presumably an early version of Nanson's.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.electorama.com/pipermail/election-methods-electorama.com/attachments/20221115/18b60127/attachment.htm>
More information about the Election-Methods
mailing list