Barak A. Pearlmutter writes ("Re: Voting system for elections"):
> It seems like a few people seem to find the argument for RRV
> convincing, and no one has objected.I feel the need to repost here, an article I posted to spi-private on the 4th of August: From: Ian Jackson <ijack...@chiark.greenend.org.uk> To: Cc: spi-priv...@lists.spi-inc.org Subject: Re: [Spi-private] SPI board election method, reanalysis of 2016 election Date: Thu, 4 Aug 2016 02:15:57 +0100 [ Someone wrote asking for a: ] > [ detailed set of analysis criteria of multi-winner voting systems ] [ (quote redacted -iwj 16.8.16) ] SPI should not be in the business of detailed analysis of voting systems, let alone the development of novel voting systems. Nor should SPI adopt a system which is highly unusual. There is only one multi-winner proportional voting system that makes sense for SPI [1] and has nontrivial adoption in the world at large. That system is STV. https://en.wikipedia.org/wiki/Proportional_representation [1] There are a handful of other common proportional multi-winner systems, including Additional Member systems, and party list PR, but they are obviously inappropriate for us. The right direction for this conversation is a discussion of which other respected institution's specific set of STV rules (answers to the edge cases) we should adopt. We would like one which has a clear description, from an authoritative source. Ideally we want a variant of which there are already one or more computerised implementations. (Even if we end up writing our own computer implementation, an existing program will provide a useful check and perhaps even come with some test vectors.) Having done another set of searches I would suggest that we should adopt Scottish STV. That is, the STV which is used in Scotland to elect local councils. Here it is laid out in the legislation: http://www.legislation.gov.uk/ssi/2007/42/schedule/1/part/III/crossheading/counting-of-votes/made The rules on actual counting are paragraphs 45-52. I also found this detailed description with examples: http://www.votingmatters.org.uk/RES/STV-WIGM.pdf Allegedly this is implemented in OpenVote: https://packages.debian.org/jessie/openstv https://github.com/OpenTechStrategies/openstv (now taken proprietary but the Free version remains available, including version 1.6 in Debian.) Thus this system has a clear and authoritative statement of the rules, and seems to have at least one computerised implementation. Or we could consider following the lead of the Apache Software Foundation. They use a Meek variant of STV and their page here suggests that they have found at least two implemnetations (although the fact that they've forked one of them isn't encouraging): https://wiki.apache.org/general/BoardVoting I haven't found (so far) a clear statement of the rules, in prose. Wikipedia suggests that New Zealand uses a version of Meek STV (and that Stack Exchange does too for some purposes), but I'm not sure if they're the same. I also found this list of tools: http://www.accuratedemocracy.com/z_tools.htm [ irrelevant section from -private deleted -iwj 16.8.16 ] Ian. -- Ian Jackson <ijack...@chiark.greenend.org.uk> These opinions are my own. If I emailed you from an address @fyvzl.net or @evade.org.uk, that is a private address which bypasses my fierce spamfilter. _______________________________________________ Spi-general mailing list Spi-general@lists.spi-inc.org http://lists.spi-inc.org/listinfo/spi-general
