Voting system R&D (Re: 2017 update to the SPI voting algorithm for Board elections)

Barak A. Pearlmutter barak at
Sun Mar 5 11:18:36 UTC 2017

On 4 March 2017 at 13:01, Markus Schulze
<markus.schulze at> wrote:
> I recommend Schulze STV.

It is a very nice algorithm, which does about as well as any
polynomial-time algorithm could using rank ballots. It certainly
overcomes a lot of the practical pathologies in ScottishSTV or more
generally IRV-based STV systems.

I would agree that, assuming rank ballots, Schulze STV is the most
sensible choice.

If I were ranking them as fit-for-purpose in the current context, I'd rank

  RRV > Schulze STV > ScottishSTV > Current System

If I wanted to be more informative, while using the entire dynamic
range, I'd say

  RRV: 99
  Schulze STV: 90
  ScottishSTV: 50
  Current System: 0

One issue with Schulze STV is that it is hard to explain to people who
are not mathematically sophisticated. That should not be a problem



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