On Mon, Nov 10, 2008 at 3:32 AM, Abd ul-Rahman Lomax <[EMAIL PROTECTED]> wrote: > Is this complicated? Yes. Is it fair? Well, up to the election of the last > candidate, yes, it is clearly fair. With the last candidate, the election > effectively becomes the same as an instant runoff voting election, with the > problems associated with that.
I don't see why the last seat being filled is that much different from the others. The negative effects are always there, though because factions aren't quite solid coalitions in practice, PR-STV doesn't display the effects quite so much (maybe). For example, assume that 2 seats are being filled A faction 16: A1>A2>A3 5: A2>A1>A3 14: A3>A2>A1 B faction 14: B1>B2>B3 5: B2>B1>B3 16: B3>B2>B1 C faction 30: C A2 and B2 (and C) are the condorcet winners in their own factions. PR-STV will run as follows Quote = 35 (approx) Round 1 A1: 16 A2: 5 A3: 14 B1: 14 B2: 5 B3: 16 C: 30 B2 and A2 both eliminated as their total is less than the next highest (14) Round 2 A1: 21 (+5) A2: 0 A3: 14 B1: 19 (+5) B2: 0 B3: 16 C: 30 A3 eliminated Round 3 A1: 35 (+14) A2: 0 A3: 0 B1: 19 (+5) B2: 0 B3: 16 C: 30 A1 elected as met the quota. No surplus transfers as exact quota, so B3 is eliminated Round 3 A1: 35 (+14) A2: 0 A3: 0 B1: 35 (+16) B2: 0 B3: 0 C: 30 B1 elected. So, the winners are (A1,B1). However, they were not the condorcet winners of their respective factions. Within each faction, standard PR-STV elects the IRV winner. CPO-STV would solve the issue. Comparing (A1,B1) to (A2,B2) A1: 16 A2: 19 B1: 14 B2: 21 A1+B1 = 30 A2+B2 = 40 Thus (A2,B2) would be CPO winners. Also, the 30 C voters would be able to upset factional 'purity' by also voting for B and C faction candidates. It is like in condorcet voting where voters of the minority party get to pick which of the candidates of the majority party gets elected. ---- Election-Methods mailing list - see http://electorama.com/em for list info
