On Sat, Feb 4, 2012 at 3:21 PM, Jameson Quinn <jameson.qu...@gmail.com>wrote:
> 2012/2/4 Bryan Mills <bmi...@alumni.cmu.edu> > >> > From: Bryan Mills <bmi...@alumni.cmu.edu> >>> > To: David L Wetzell <wetze...@gmail.com> >>> > > If there are 3-5 seats STV then the number of candidates won't >>> > proliferate >>> > > too much and there'd be 5-7 places to vote. This would keep things >>> > > reasonable. >>> > >>> > To get reasonable proportionality with only 3-5 seats per district >>> > you'd probably need to go to an MMP system, with all its added >>> > complexity. Otherwise Droop proportionality doesn't buy you much over >>> > FPTP; with 5 seats the Droop quota measures to a precision of ~17%, >>> > and the remaining 17% in each district is still susceptible to >>> > gerrymandering. >>> > >>> >>> Not much? >>> The goal here is not perfectionism wrt proportionality. >>> The goal is to increase proportionality and to increase the number of >>> competitive seats >>> and to reduce the cut-throat competitive nature of US political rivalry >>> between its two biggest parties >>> so they can't dominate the other and have more incentives thereby to work >>> together on the many issues that need work. >>> >> >> I'm doubtful that 3-5 candidate districts actually would "increase the >> number of competitive seats". Each major party ends up with 1-2 safe >> seats, and at that level of granularity gerrymandering and geographical >> polarization are still significant enough to render the last seat >> non-competitive in most districts. (It would increase proportionality >> somewhat - by transforming some of the safe-by-gerrymandering seats into >> safe-by-Droop-proportionality seats - but you seem to be arguing that >> proportionality isn't as important as competition.) >> >> Suppose we have two parties with a 50/50 split and 5 seats per district, >> with one party more popular in urban areas and one more popular in rural >> areas. And suppose that the district lines are drawn such that 4/5 of >> districts are slightly more rural than average and 1/5 of districts are >> more urban than average, so that the 5th seat in each district becomes >> relatively safe as well. (We can do this fairly easily using geographical >> boundaries by centering 1/5 of the districts around cities.) >> >> Scale that up to 400 legislators (80 districts). What do we end up with? >> 320 "natural" safe seats guaranteed by Droop proportionality (160 for >> each party) >> 80 gerrymandered-safe seats for the rural party >> 20 gerrymandered-safe seats for the urban party >> > > First, your numbers add up to 420. I think you meant 64/16 for the safe > seats, which is only a 56/44 advantage, not 60/40. > Oops! I had started calculating with 500, then switches to 400 and forgot to update some of the numbers. You're right, I should have had the gerrymandered seats at 64/16, and that does give a 56:44 advantage rather than 60:40. (Of course, if you throw in some third-parties the whole analysis changes too; the 50/50 example is meant to be representative of an idealized two-party world.) Note that the "safe" seats would still swing if there were a swing in > national mood of around something less than 8%, not something less than 25% > as in single-member districts. And the more highly-gerrymandered the map > is, the tighter that margin, and so the greater the chances of it > backfiring against the gerrymandering party. Gerrymandering is a fine art, > but 8% doesn't leave a whole lot of room to play with. Considering safety > margins and misfires, I doubt that the gerrymandering party could get > anything close to the 6% representation advantage your (corrected) numbers > suggest. So, while 2-3% unfairness is still a problem, I think it's a big > step up from where we are. > Hmm, interesting. So maybe that's not as much of a concern as I thought; I'll have to give it some more consideration. I don't think it solves the problem of multiple axes of policy preference, though, and 16% is a lot of voters to leave unrepresented in the multiparty case. Now, despite a 50/50 natural split, the rural party has a 60% >> supermajority. And, of course, if you draw the district lines differently >> you can do the same thing for the urban party. >> >> So there's still relatively little hope that a system with such small >> districts would produce a party-proportional legislature. As you point out >> elsewhere, it might still be possible to get an ideologically-proportional >> legislature if you can get the parties themselves to shift ideologies. >> >> >> > If you assume two major parties with ~40% of the electorate each, that >>> > means that the 5th seat in each district is noisy -- but it's not >>> > random noise, it's systematically biased by the parties' voting >>> > strategies and the choice of district boundaries. Larger districts >>> > allow finer-grained Droop quotas and thereby reduce that noise. >>> >>> dlw: Smaller districts engender less opposition from those in power. >>> They keep the constituent-legislator relationship more so. >>> >> >> Absolutely agreed that smaller districts engender less opposition from >> those in power. That's because smaller districts don't fix the biases that >> keep them in power. >> >> They do maintain the constituent-legislator relationship, *for the subset >> of voters who voted in favor of the legislator*. For the remaining Droop >> quota of un- or under-represented constituents the nonexistence of the >> constituent-legislator relationship is also maintained. >> > > Here's my chance to plug PAL > representation<http://wiki.electorama.com/wiki/PAL_representation>, > which does PR but uses existing-sized districts and preserves a specific > constituent-legislator relationship for all but (up to) one Droop quota of > voters. > Hmm.. Interesting, but it seems too complicated to me. It's got all the complication of delegation, approval, and STV - with a bit less voter burden on the approval side since only the candidates have to pick approval thresholds - plus the variable quota and elimination procedure, which doesn't have a strong intuitive interpretation to me. Maybe if you can find a way to simplify the counting algorithm - or a way to explain it with a more intuitive connection - but otherwise I think it would be too difficult to get adopted. > >> But if we assume that partial rankings are effective, there's still >>> the >>> > >> strategy/computation tradeoff to deal with: allowing truncated >>> ballots >>> > >> still doesn't help with favorite-betrayal, and STV variants less >>> > >> susceptible to favorite-betrayal are also less susceptible to >>> efficient >>> > >> counting. >>> > >> >>> > > >>> > > dlw: Truncated ballots may not end favorite betrayal, but it'll help >>> with >>> > > it. >>> > >>> > I don't see how; please elaborate. >>> > >>> >>> This is essentially the same arg that IRV does not end the fact that some >>> will still on occasion be pressured to betray their favorite. >>> But it'll be of less consequence when it happens. It won't be 3rd party >>> dissenters, it'll be the supporters of a major party that does >>> not position itself near the true political center who get pressured to >>> betray their favorite and that in turn will pressure the major party >>> to adapt or die. >>> >> >> Are you saying that favorite-betrayal isn't a problem when those forced >> to do it belong to a major party? I hope I'm just misunderstanding your >> point, but it sounds to me like you're describing a system like FPTP but >> with major-party spoilers substituted for minor-party spoilers. >> >> >> > >> With an implicit "first-preference" approval, it has the same >>> problem as >>> > >> traditional STV (i.e. IRV), namely of unduly rewarding >>> > favorite-betrayal. >>> > >> With an implicit "all-ranked" approval, the overall system would >>> likely >>> > >> violate later-no-harm with much higher frequency; by expressing a >>> > >> preference between two dispreferred candidates one might >>> unintentionally >>> > >> put the higher of the two in contention. >>> > >> >>> > > >>> > > dlw: I'd say empirically we'd see just how high of a frequency LNH >>> would >>> > be >>> > > violated. Jameson Quinn had a hard time coming up with a >>> pathological >>> > > example for IRV3/AV3 and I imagine it'd be similar for the above. >>> The >>> > 1st >>> > > stage would reduce the number of candidates to N+2 and it seems >>> likely >>> > that >>> > > the N+2nd and N+3rd candidates in terms of "all-ranked" approval are >>> less >>> > > likely to be among the N winners. >>> > >>> > Hmm, ok. I'm operating on the assumption that voters will vote >>> > strategically if doing so is easy, and will vote approximately >>> > honestly if strategic voting is difficult. >>> > >>> >>> okay. >>> >>> > >>> > We're taking the top S+k winners and running some ideal STV method on >>> > them; let's try to find an "easy" strategy. Here's my idea: >>> > 1) Gather a set of related parties to form a majority-coalition. >>> > 2) Have the coalition propose exactly S+k candidates. >>> > >>> >>> good luck coordinating that.. >>> >>> 3) Ask coalition voters to vote for all of the coalition candidates in >>> > any order they choose. >>> > >>> > Since a majority of candidates approve of every coalition candidate >>> > and disapprove of every competing candidate, the coalition candidates >>> > win the approval vote. >>> > By adding the "approval" phase to the STV election, I'm able to turn a >>> > simple majority into a 100% supermajority. >>> >>> >>> > Is there a flaw in my strategy? (I don't think there is, but I may be >>> > missing something.) If not, we'll either need to abandon a fixed >>> > limit on the number of candidates or we'll need something more >>> > sophisticated than a simple approval-vote to filter them. >>> > >>> >>> dlw: It's not realistic. >>> >>> You'd need to have serious intra-party discipline to keep the no. of >>> candidates down to S+2 >>> and to get a majority of voters all to vote for all of that S+2 >>> candidates. >>> That is a serious coordination problem. >>> >>> But if it did happen then it'd "work" in terms of making the leading >>> coalition of parties cast a broad net that strongly met the needs of most >>> people. This would be much better than a bunch of non-competitive >>> single-winner elections. In that case, we're in DINO land. >>> >> >> By "strongly met the needs of most people" you appear to mean "met the >> needs of a bare majority of people marginally better than the >> alternatives". My concern is that in this scenario 25% of the electorate >> would benefit substantially, 25% would benefit marginally, and the >> remaining 50% would be arbitrarily worse off. That's essentially the same >> worst-case behavior as the current majority-of-majorities setup, but with a >> simpler strategy required to implement it. >> >> That being the case, I think we'd be better off with small-district STV >> than with large-district STV with this sort of approval-based filtering. >> >> >> > >> It may well be that these issues are all less severe than in the >>> > >> deterministic alternatives to STV, but I still think they're enough >>> to >>> > >> merit consideration of nondeterministic alternatives. >>> > >> >>> > > >>> > > In terms of the US's political culture, nondeterministic >>> alternatives are >>> > > not going to happen anytime in the near future and we need electoral >>> > reform >>> > > ASAP!!!! >>> > >>> > Sadly, I think both nondeterminism and STV share the "not going to >>> > happen in the near future given political culture in the US" >>> > classification, given that US law requires single-winner FPTP >>> >>> > elections for federal representation and the major parties (who >>> > control the legislature and benefit greatly from FPTP) have no >>> > incentive to change that law. >>> >>> dlw: STV need not end 2-party domination. Reforms that do not end >>> 2-party >>> domination are more fit in the US and should be the only ones pushed. >>> And, as I've shown, it's implementation can be simplified. >>> Thus, it can become a political jujitsu issue, whereby it is more >>> rational >>> for those in power to accommodate than to resist the proposed change. >>> >> >> The belief that the 2-party system can accurately reflect voter consensus >> relies heavily on the assumption that voters' differences of opinions >> correlate sufficiently well with a single dimension of variability, so that >> tending toward the center along a single axis produces centrist results on >> all issues. I do not accept that assumption: in my experience, Americans >> disagree along at least two axes that do not correlate perfectly (fiscal >> policy and social policy). >> >> >> > So as far as I can tell the only option for meaningful reform is a >>> > constitutional amendment, and that means reforming 75% of the states >>> > as a first step. This is not a short-term process. >> >> >>> I think one could argue that the current law requiring single-winner >>> elections is discriminatory twds minorities, and adopted under bad >>> circumstances, and thereby unconstitutional. This would not require a >>> constitutional amendment. >>> >> >> I think you're perhaps overly optimistic about the willingness of courts >> to overturn election law. But we'll see - I'd be thrilled to be proven >> wrong about this one. >> >> ---- >> Election-Methods mailing list - see http://electorama.com/em for list >> info >> >> >
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