[EM] Quotaless STV

[Toby Pereira]

I was wondering if you could run a Single Transferable Vote election without 
worrying about having a Droop/Hare etc. quota.* I'm sort of thinking out loud 
and I'm not sure what sort of results this might produce.

In the fist round, all candidates transfer away as many votes as they can get 
away with so that they don't end up in last place. So if there are 10 
candidates, then having more than 1/(n+1) votes will guarantee not finishing in 
last place. Because not every voter will rank every candidate, some candidates 
will be "stuck" at much higher than 1/(n+1) and so others may get away with 
transferring more away and end up with less than this and still not finish last. 
1/(n+1) isn't a specific quota. The candidate in last place is then eliminated.

In each subsequent round, the transferred votes are all reset (de-transferred) 
and the process starts again. Continue until the right number of candidates 
remain for the number of available seats.

Obviously any candidate reaching the Droop Quota will automatically get elected, 
but no quota is actually built into the system at any point. You could also use 
this system for single winners as an alternative to the Alternative Vote 
(Instant Run-off).

But by eliminating one candidate at a time, it's not a very "Condorcety" method 
but could possibly be adapted. You could certainly compare set of candidates 
that differed only by one. I might come back to that.

*Actually, I don't know much about STV methods - is Schulze STV quotaless? I've 
had a look at its Wikipedia article, and although in some parts it's as clear as 
mud, it appears not to have a specific quota.
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