On Thu, Jan 21, 2010 at 7:34 PM, Abd ul-Rahman Lomax <[email protected]> wrote: > At 04:41 PM 1/21/2010, Jonathan Lundell wrote: >> >> On Jan 21, 2010, at 1:32 PM, Kathy Dopp wrote: >> >> > Terry, You cleverly conveniently change all the definitions whenver it >> > is necessary to make yourself and Fairytale Vote right on the "facts". >> >> Define "spoiler", please, unambiguously. > > The term has usage, and must be understood from that. A formal definition, > nailing it down, would be arbitrary. But Kathy's definition is one > reasonable one that matches common usage. > > But there is another which is broader and, to distinguish this from the
Abd ul, actually your definition below is *narrower* not broader, because it narrows the number of cases that fit the definition. I simply took my broader definition that includes all cases of nonwinning candidates who alter election outcomes by their presence, from Arrow's fairness criteria which is describes less simply here: "Arrow's Fairness Criteria" http://www.ctl.ua.edu/math103/Voting/whatdowe.htm#The%20Independence%20of%20Irrelevant%20Alternatives%20Criterion So you see that my definition is actually Arrow's definition of spoiler, not my own original definition. Kathy > common usage, I call the common usage the "first order spoiler effect." It > refers to minor candidates, with hopelessly low support, who alter the > outcome between two major candidates by drawing away votes preferentially > from one, from voters who would otherwise vote for that one. The application > most common is with plurality, but also top-two runoff and, similarly, IRV, > where as little as one vote and some back luck in the resolution of a tie > can cause the effect. > > To define this l.e. spoiler effect more crisply would be arbitrary. > > But then there is a more generalized "spoiler effect," more commonly > referred to as center squeeze. It's a spoiler effect, all right, in > substance, because an extremist candidates, who would lose in a direct > contest between either the centrist or the other extremist, draws enough > higher preference votes away from the centrist to reduce that centrist below > second rank in first preference. So this is an IIA problem. > -- Kathy Dopp Town of Colonie, NY 12304 phone 518-952-4030 cell 518-505-0220 http://utahcountvotes.org http://electionmathematics.org http://kathydopp.com/serendipity/ Realities Mar Instant Runoff Voting http://electionmathematics.org/ucvAnalysis/US/RCV-IRV/InstantRunoffVotingFlaws.pdf Voters Have Reason to Worry http://utahcountvotes.org/UT/UtahCountVotes-ThadHall-Response.pdf Checking election outcome accuracy --- Post-election audit sampling http://electionmathematics.org/em-audits/US/PEAuditSamplingMethods.pdf ---- Election-Methods mailing list - see http://electorama.com/em for list info
