Poll - Is endless September a threat to LW and what should be done?

The fear is that this is due to a selection effect. Of the people I know through LW, a disappointing number have stopped reading the site. One of my hobbies, for over a decade now, has been posting on forums, and so the only way I'd stop reading / posting on LW is if I find a forum more relevant to my interests. (For the curious, I've moved from 3rd edition D&D to xkcd to here over that timeframe, and only post in xkcd's MLP and gaming threads these days.) For many of the former LWers I know, forum-posting isn't one of their hobbies, and they came here for the excellent content, primarily by EY. Now that there aren't blog posts that they want to read frequently enough, they don't come, and I'm not sure that any of them even know that EY has started posting a new sequence.

I think that this fear is mostly misplaced, because the people in that class generally aren't the people posting the good content, and I think any attempt to improve LW should be along the lines of "more visible good content" and not "less bad content," but it's important for evaporative cooling reasons to periodically assess the state of content on LW.

I am annoyed by both. Not enough to consider leaving this weedy garden yet.

The possibility still warrants consideration, even if it isn't actively harming the site

Same here, but I have no clue how to address this problem. I suspect making discussion posts complaining about people complaining about cultural erosion would be the wrong approach.

Discussion is filled with META, MEETUP, SEQ RERUN, links to boring barely-relevant articles

The website structure needs to be changed. "Main" and "Discussion" simply do not reflect the LW content today.

We should have a separate "Forum" (or some other name) category for all the non-article discussion threads like Open Thread, Media Thread, Group Rationality Thread, and stuff like this.

Then, the "Discussion" should be renamed to "Articles" (and possibly "Main" to "Main Articles") to make it obvious what belongs there.

Everything else should be downvoted; optionally with a comment: "This belongs to the Open Thread". (And if the author says they didn't know that Open Thread exists, there is something seriously wrong... about the structure of the website.)

I feel like I wrote this to the LW discussions at least dozen times...

there's nothing interesting to talk about anymore.

I think there are interesting things here. They are just drowned in too many less interesting things.

Let's look at the numbers: 6 articles so far on Dec 9th; 6 articles on Dec 8th; 4 articles on Dec 7th; 11 articles on Dec 6th; 8 articles on Dec 5th; and some of the articles from Dec 4th -- less than one week ago -- already don't fit on the first "Discussion" page. (The exact numbers may differ depending on your Preferences settings.) The page is scrolling insanely fast. If I stopped reading LW for one week, I would have problem to catch up with all the new stuff; I would probably just skip some of that. That's not good if we have too much stuff, but low average quality.

We don't downvote enough. Let me explain -- if someone makes a post that is not very good, but is not completely stupid or trolling also, it will almost certainly gain more upvotes that downvotes. Because it feels wrong to punish someone only for being uninteresting. But in terms of rewarding/punishing behavior, we probably should punish them. If we try to be too friendly, the site will become boring, precisely because most of the social talk is not about giving new information.

Perhaps it could help to use some timeless deciding. If you read an article, ask yourself a question: "If the next week here would be 10 new articles like this, would it make LW better or worse?" If the answer is worse, downvote it. Because although the same author will not write 10 more articles like this during the next week, other authors will.

TL;DR -- I think the Eternal September is most visible on the article level, because it is not obvious what kind of content belongs here. "Discussion" is horribly misleading -- we don't want discussion-level articles. That's what the comments and Open Threads are for.

One issue with the LW/CFAR approach is that the focus is on getting better/more efficient at pursuing your goals, but not on deciding whether you're applying your newfound superpowers to the right goals. (There's a bit of this with efficient altruism, but those giving opportunities are more about moving people up Maslow's hierarchy of needs, not on figuring out what to want when you're not at subsistence level).

Luke's recent post suggest that almost no one here has the prereqs to tackle metaphysics or normative ethics, but that always has seemed like the obvious next topic for rationality-minded people. I was glad when Luke was writing his Desirism sequences back at CSA, but it never got to the point where I had a decent enough model of what normative claims desirism made to be able to evaluate it.

Basically, I think these topics would let us set our sights a little higher than "Help me optimize my computer use" but I think one major hurdle is that it's hard to tackle these topics in individual posts, and people may feel intimidated about starting sequences.

idea threads where the highest comment has more votes than the thread itself (i.e. a crappy idea)

It depends-- if the higher-voted comments are expending on the original post, then I'd say the post was successful because it evoked good-quality thought, assuming that the voters have good judgement. If the higher-voted comments are refuting the original post, then it was probably a bad post.

Do you have a theory as to why there aren't enough good users, or why they are not writing good articles?

I second these motions... with a vengeance. For is it not said:

The revolutionary war is a war of the masses; it can be waged only by mobilizing the masses and relying on them.

and

Liberalism is extremely harmful in a revolutionary collective. It is a corrosive which eats away unity, undermines cohesion, causes apathy and creates dissension. It robs the revolutionary ranks of compact organization and strict discipline, prevents policies from being carried through and alienates the Party organizations from the masses which the Party leads. It is an extremely bad tendency.

and especially:

To criticize the people's shortcomings is necessary, . . . but in doing so we must truly take the stand of the people and speak out of whole-hearted eagerness to protect and educate them.

A related request: there are a lot of goals common enough that better achieving these goals should be of interest to a large-ish portion of LW. I'm thinking here of: happiness; income; health; avoiding auto accidents; reading more effectively; building better relationships with friends, family, dating partners, or co-workers; operationalizing one's goals to better track progress; more easily shedding old habits and gaining new ones.

Could we use our combined knowledge base, and our ability to actually value empirical data and consider counter-evidence and so on, to find and share some of the better known strategies for achieving these goals? (Strategies that have already been published or empirically validated, but that many of us probably haven’t heard?) We probably don’t want to have loads and loads of specific-goaled articles or links, because we don’t want to look like just any old random internet self-help site. But a medium amount of high-quality research, backed by statistics, with the LW-community’s help noticing the flaws or counter-arguments -- this sounds useful to me. Really useful. Much of the advantage of rationality comes from, like, actually using that rationality to sort through what’s known and to find and implement existing best practices. And truth being singular, there’s no reason we should each have to repeat this research separately, at least for the goals many of us share.

Anna Salamon, 2009. So this "destruction" was at least semi-planned.

hypercontrarian archconservative clique

lulz. Why do I feel identity-feels for that phrase? I should watch out for that, but,

which might be wrong about everything

That's what I thought a few months ago. Then everything turned inside out and I realized there is no god . What a feeling! Now I see people confidently rationalizing the cultural default, and realize how far we have to go WRT epistemic rationality.

If EY didn't intend for said "destruction" to happen, he should have chosen a website model more suitable to that end.

tl;dr: The following is a non-profit fan-based parody. Less Wrong, the Singularity Institute, and the Centre for Applied Rationality are owned by Hogwarts School, Chancellor Ray Kurzweil, and the Bayesian Conspiracy. Please support the official release.

Troll Wrongosphers with Baumeister and Eddington, not Benedict and Evola

Wrongosophical trolling should be based on genuinely superior psychological insights ("Baumeister" for breakthroughs in social psychology such as those summarized in Vohs & Baumeister 2010) and on crackpot science that is nonetheless difficult to debunk ("Eddington" for the fundamental theory described in Durham 2006). Starting from reaction and religion, as many trolls still do, both (1) promotes unpleasant ideas like God and conservatism and (2) fails to connect with the pragmatic and progressive sensibility of 21st-century culture. Once young trollosophers are equipped with some of the best newthink and pseudoscience, then let them dominate the subversive paradigm. I'll bet they get farther than the other kind.

LW needs a king.

LW as a place to test applied moldbuggery, right?

Communities and democratic methods suck at doing the kind of strategic, centralized, coherent decision making that we really need.

Kings also suck at it, in the average. Of course, if we are lucky and find a good king... the only problem is that king selection is the kind of strategic decision humans suck at.

LW needs a king.

Why “king” rather than “monarch”? Couldn't a queen do that?

LW needs a king.

The standard term is Benevolent Dictator for Life, and we already have one. What you're asking for strikes me as more of a governor-general.

I don't think a CEO level monarch is necessary though I don't know what job title a community "gardener" would map to. Do you think a female web developer who obviously cares a lot about LW and can implement solutions would be a good choice?

This doesn't look like it's very likely to happen though, considering that they're changing focus:

For 12 years we've largely focused on movement-building through the Singularity Summit, Less Wrong, and other programs... But in 2013 we plan to pivot so that a much larger share of the funds we raise is spent on research.

Then again maybe CFAR will want to do something.

Eternal September probably isn't our biggest issue

What would that be in your opinion?

the massive increase in users is likely to cause problems, and those problems should be addressed.

Thank you pleeppleep for bringing this up. I am especially curious about why this thread has been hovering between -3 and 1 karma when the majority of people are concerned about this, and have chosen a solution for at least one problem. If you get any theories, please let me know.

more and more opinions that should be presented in discussions just aren't.

People have theorized that the users who might post these discussions are too intimidated to post. Do you have additional theories, or do you think this is the problem, too?

I maintain that Lesswrong is the best thing to ever happen to me

It is one of the best things that's happened to me, too. I feel strongly about protecting it.

We need a more general assessment of the problem and ways to solve it.

How would you describe the problem? What would you suggest for ways to assess it?

I honestly do miss some of the (admittedly somewhat elitist) optimism that used to flood this site.

What do you mean by that exactly? (No, I will not bite your head off about elitism. I have strong feelings about specific the type of elitism that means abusing others with the excuse that one is "better than" them, but I am curious to hear about any and all other varieties.)

We're rationalists. We aimed to build gods, eradicate the plagues of the human mind, and beat death itself. We said we'd win a staring contest with the empty, uncaring abyss of reality. We sought to rewrite human knowledge. To decide what, over the past 8 thousand years, was useful, and what wasn't.

Wow. That's inspirational. Okay, I think I know what "elitist optimism" means now. I don't agree with the goal of building gods (an awesome idea but super dangerous), but I want to quote this in places. I will need to find places to quote it in.

If we can't keep one little community productive, we might as well hang up our hats and let the world get turned into paper clips, cause we've shown there's not much we can do to about it one way or the other.

Upvote. (:

I agree strongly with # 2,3 and 4

Particularly 2, since the absence of category divisions makes all discussion harder to browse....at least for me

Some absolute figures:

R> lw2009 <- read.csv("2009.csv"); lw2011 <- read.csv("2011.csv"); lw2012 <- read.csv("2012.csv")
R>
R> sum(as.integer(as.character(lw2009$IQ)) > 140, na.rm=TRUE)
[1] 31
R> sum(as.integer(as.character(lw2011$IQ)) > 140, na.rm=TRUE)
[1] 131
R> sum(as.integer(as.character(lw2012$IQ)) > 140, na.rm=TRUE)
[1] 120
R>
R> sum(as.integer(as.character(lw2009$IQ)) > 150, na.rm=TRUE)
[1] 20
R> sum(as.integer(as.character(lw2011$IQ)) > 150, na.rm=TRUE)
[1] 53
R> sum(as.integer(as.character(lw2012$IQ)) > 150, na.rm=TRUE)
[1] 42

Well, I agree, but "mere" probably isn't a sensationalist enough way to describe a 7 point drop in IQ.

A. Well, 52% is the real figure. That's just math.

B. We don't know why the average IQ dropped. It could be because some of the gifted users have left.

C. Saying "if the data is good, LessWrong has lost 52% of it's giftedness" in the context of an average should be interpreted as "if the data is good, LessWrong's average has lost 52% of it's giftedness". This is correct. I feel that this is picking at details, but I'll go add the word "average" so that nobody else does it.

If you feel there is some deeper problem with my statement, please continue. If not, does this address your criticism?

I don't feel inadequate but I do feel likely to get jumped all over for mistakes. I've realized that you really need to go over things with a fine-toothed comb, and that there are countless cultural peculiarities that are, for me, unexpected.

I've decided that the way I will feel comfortable posting here is to carefully word my point, make sure that point is obvious to the reader, identify and mentally outline any other claims in the piece, and make sure every part is supported and then (until I get to know the culture better) ask someone to check it out for spots that will be misunderstood.

That has resulted in me doing a lot of research. So now my main bottleneck is that I feel like posting something requires doing a lot of research. This is well and good IMO, but it means I won't post anywhere near as much simply because it takes a lot of time.

I've wondered if it would do us good to form a writer's group within LW where people can find out what topics everyone else is interested in writing about (which would allow them to co-author, cutting the work in half), see whether there are volunteers to do research for posts, and get a "second pair of eyes" to detect any karma-destroying mistakes in the writings before they're posted.

A group like this would probably result in more writing.

Yep, that's my experience as well. Recently, I decided "screw what LW thinks" and started posting more thoughts of mine, and they're all getting upvoted. My vague intuitions about how many upvotes my posts will get doesn't seem to correlate very well with how many upvotes they actually get either. This is probably true for other people as well.

The only potential problem with this, IMO, is if people think I'm more of an authoritative source than I actually am. I'm just sharing random thoughts I have; I don't do scholarly work like gwern.

Every school has this problem: how to welcome people who as yet know little and raise them up to the standard we want them to reach, while allowing those already there to develop further. Universities solve this with a caste distinction between the former (students) and the latter (faculty), plus a few bridging roles (grad student, intern, etc.). On a much smaller scale, the taiko group I play with has found the same problem of dividing beginners from the performing team. It doesn't work to have one class that combines introductory practice with performance rehearsal. And there can be social problems of people who simply aren't going to improve getting disgruntled at never being invited to join the performing team.

In another comment I suggested that this division already exists: LessWrong and CFAR. So the question is, does LessWrong itself need a further splitting between welcoming beginners and a "serious" inner circle? Who would be the advanced people who would tend the beginners garden? How would membership in the inner circle be decided?

Missions, perhaps? A few ideas: "We are rationalists, ask us anything" as an occasional post on reddit. Drop links and insightful comments around the internet where interesting people hang out.

Effect #1 is to raise the profile of rationality in the internet community in general, so that more people become interested. Effect #2 is that smart people click on our links and come to LW. I myself was linked to LW at first by a random link dropped in r/transhumanism or something. I immediately recognized the awesomeness of LW, and ate the sequences.

On the home front, I think we should go whole hog on being a well kept garden. Here's why:

1. There's no such thing as a crowd of philosophers. A movement should stay small and high quality as long as possible. The only way to maintain quality is to select for quality.

2. There are a lot of people out there, such that we could select for any combination of traits we liked and be unlikely to run out of noobs. We will have a much easier time at integration and community maintenance if we focused on only attracting the right folks.

I don't think we have to worry about creating rationalists from normals. There are enough smart proto-rationalists out there just itching to find something like LW, that all we have to do is find them, demonstrate our powers, and point them here. We should focus on collecting rationalists, not creating them. (Is there anyone for whom this wouldn't have worked? Worse, is there any major subset of good possible LWers that this turns off?)

As for integrating new people, I think the right people will find a way and it's ok if everyone else gets turned off. This might be pure wishful thinking. What are other people's thoughts on this?

Overall, have the low level missionary work happen out there where it belongs. Not in these hallowed halls.

As for what to do with these hallowed halls, here's my recommendations:

1. Elect or otherwise create an Official Community Organizer who's job it is to integrate all the opinions and make the decisions about the direction of LW. I think they would also provide direct friendly encouragement to the meetup organizers, who are currently totally lacking in coordination and support.

2. Sort out this crazy discussion/main bullshit. The current setup has very few desirable properties. I don't know what the solution should be, but we should at least be trying things. This of course requires someone to come up with ideas and code them. Would it be bad to try a different arrangement for a month?

3. Fix the front page. The valuable stuff there is approximately the banner, "featured posts", and current activity links. Everything else is of dubious value. The LW front page should be slick. Right now it looks like it was designed by a committee, and probably turns off most of our potentials.

4. Properly organize and index the LW material. This is a pretty big project; LW has thousands of good posts. This project neatly fits in with and builds on the current work in the wiki. The goal is a single root page from which every major insight is linked in at least a passable reading order. Like a textbook TOC. This obviously would benefit from wiki-improvements in general, for which I recommend merging wiki and LW accounts, and making wiki activity more visible and encouraged, among other things.

5. Friendship threads where we pick a partner and get to know them. Would generally increase community-coherence and civility. After meeting a lot of the other posters at the CFAR minicamp, I get more friendly feels in the community.

6. Somehow come up with the funding and political will to do all this stuff.

7. Something about trolls and idiots. Is this even a problem once the above are solved?

As for you, Epiphany, I want to commend you for still being at the throat of this problem, and still generating ideas and analysis. I'm impressed and humbled. Keep up the good work.

If the recent arrivals vote on mass that there is no problem

Well that's not what's happened. Most of the votes are in, and the majority has voted that they're very or somewhat concerned.

Any other concerns?

On a different note, and as anecdotal evidence, I have been lurking on LW for years now, and went to a CFAR camp before posting a single comment - In fear of karma retribution and trolling. (I know that its a bad strategy and that I shouldn't care as much. Sadly, I'm not as good at self-modification as I would like to be sometimes.)

On the other had, lurking for a while before posting is very much what we want new users to do.

An elite intellectual community can^H^H^H has to mostly reject newcomers, but those it does accept it has to invest in very effectively (while avoiding the Objectivist failure mode).

I think part of the problem is that LW has elements of both a ground for elite intellectual discussion and a ground for a movement, and these goals seem hard or impossible to serve with the same forum.

I agree that laziness and expecting people to "just know" is also part of the problem. Upvoted for the quote.

The obvious analogy of childood here would be lurking, which does not require any special effort to "teach them that, whether they're twelve, twenty two, or eighty two"

I have come across more than a handful of people who don't excel in traditional IQ tests, but who are nevertheless very capable of presenting coherent, well-argued insights. Does it matter to me that their IQ is 132 instead of 139? No. Who cares about the average IQ among members of the LW community as long as we continue demonstrating the ability to engage in thoughtful discussions and generate valuable conclusions?

Another possibility here is that your perceptions of intelligence levels are really off. This isn't too unlikely as I see it:

I've heard reports that people with super high IQs have trouble making distinctions between normal and bright, or even between moderately gifted and mentally challenged. I frequently observe that the gifted people I've met experience their own intelligence level as normal, and accidentally mistake normal people for stupid ones, or mistakenly interpret malice when only ignorance is present (because they're assuming the other person is as smart as they are and would therefore never make such an ignorant mistake).

If the intelligence difference you experience every day is 70 points wide, your perceptions are probably more geared to find some way to make sense of conflicting information, not geared to be sensitive to ten point differences.

As a person who has spent a lot of time learning about intelligence differences, I'd say it's fairly hard to perceive intelligence differences smaller than 15 points anyway. The 30 point differences are fairly easy to spot. A large part of this may be because of the wide gaps in abilities that gifted people tend to have between their different areas of intelligence. So, you've got to figure that IQ 130 might be an average of four abilities that are quite different from each other, and so the person's abilities will likely overlap with some of the abilities of a person with IQ 120 or IQ 140. However, a person with an IQ of 160 will most likely have their abilities spread out across a higher up range of ability levels, so they're more likely to seem to have completely different abilities from people who have IQs around 130.

The reason why a few points of difference is important in this context is because the loss appears to be continuing. If we lose a few points each year, then over time, LessWrong would trend toward the mean and the culture here may die as a result.

I really don't see why Epiphany is so obsessed with IQ. Based on anecdotal evidence, there is not much of a correlation between IQ and intellect beyond the first two standard deviations above the mean anyway.

Try reading this response to Slade's suicidal post and you will begin to understand why giftedness is relevant, in a general sense. Gifted people, especially highly gifted people, are very different from most. If you haven't seen that for yourself, then perhaps:

A. You haven't met someone with an IQ like 160 or 180. Those people tend to be very, very different so maybe you are only comparing people with much smaller IQ differences with each other.

B. The people you've met with super high IQs behave in a way that blends in when they're with you and minimize social contact so that you don't notice the differences. The ones that I know tend to do that. They don't just barge into a room and solve unsolvable science problems for all to see. They tend to be quiet, or away hiding in their caves.

C. You never asked the IQs of the smartest people you know and therefore haven't seen the difference.

D. You feel strongly that we should express egalitarianism by treating everyone as if they are all intellectually exactly the same. There's a movement of people who want to believe everyone is gifted, that giftedness does not exist, that it goes away, or that gifted people have some horrible flaw that "balances" them out, that they should be stifled in schooling environments in order to destroy their giftedness so that they're intellectually equal to everybody else, and all kinds of other things. Many people hate inequality and cannot deal with the scientifically proven fact that intellectual inequalities do exist. Wanting to solve inequalities is great, but it's important that we don't deny that intellectual inequalities exist, and it's absolutely, undeniably wrong to stifle a person, especially a child, in the name of "equality". I care a lot about this cause. I hope you read this PDF by developmental psychologist Linda Silverman (I want everyone to read it):

Myths about the Gifted

I have come across more than a handful of people who don't excel in traditional IQ tests, but who are nevertheless very capable of presenting coherent, well-argued insights.

One in six gifted people has a learning disorder. About one in three are creative. Some of them have mental disorders or physical conditions. All three of these can reduce one's IQ score and should be compensated for on an IQ test. Unfortunately, a lot of the IQ tests that are administered (by Mensa for instance) do not include any sort of evaluation for multiple exceptionalities (jargon for when you've got multiple differences that affect learning).

Who cares about the average IQ among members of the LW community as long as we continue demonstrating the ability to engage in thoughtful discussions and generate valuable conclusions?

You missed my point. My point was: "LessWrong may be headed toward cultural collapse so we need some way to determine whether this is a real threat. Do we have numbers? Yes we do. We have IQ numbers." The IQ blurb was a data point for an ongoing discussion on the controversial yet critical topic of whether LessWrong's subculture is dying. My point was not "Oh no, we cannot lose IQ points!"

Let me ask you this: If you were attempting to determine whether LessWrong is headed for cultural collapse, and you knew that the average IQ at LessWrong was decreasing, and you knew that you needed to supply the group with all related data, would you justify omitting that? You would have to include it if you want to be thorough, as it was related. That point is at the top because it's new - most of the other points have been presented before. I couldn't present the IQ data until it had been thoroughly analyzed.

I'm a psychology enthusiast with a special interest in developmental psychology, specifically in gifted adults. When I go to the trouble of thoroughly analyzing some data and sharing information that I gathered while pursuing a main interest of mine, I very much prefer respectful comments in return such as "I don't see the relevance of IQ in this context, would you mind explaining?" as opposed to being called "obsessed". I prefer it even more if the person double checks their own perceptions to clear up any confusion on their own before responding to me.

I have a passion for learning which is not pathological. The term "obsessed" is inappropriate and offensive. Try this: Gwern, one of LessWrong's most prominent and most appreciated members, also has a passion for learning. Check out his website. If you do not appreciate the thoroughness with which he pursues truth - a major element of LessWrong culture - then perhaps it's time to consider whether this is a compatible hang out spot.

If you are vain and think that doing well on an IQ test is a really important way of signalling intellect, then go ahead and keep doing exercises in Mensa practice books, though that would not make you more capable of critical thinking or logical argumentation.

Was your intent to insult me?

Good points, but a bucket of picked fruit does not make a pie.

We've generated a lot of really valuable insight on this site, but right now it has no structure to it.

Maybe it's time to move from an article-writing phase to a knowledge-organization phase.

This might be virtuous doubt. Have you considered the opposite?

See Also:

Luke's article on overconfident pessimism.

My IQ related links in the OP.

If you want to spread ideas, don't bring outsiders in, send missionaries out.

On the other hand if the new people dilute or overwhelm LW culture and lower the sanity waterline on LW, it won't be able to raise the sanity waterline in the rest of the world. It's a balancing act.

Firstly, it is not my view that we should not bring in new people. My view is that if we bring in too many new people at once, it will be intolerable for the old users and they will leave. That won't raise the sanity waterline as effectively as growing the site at a stable pace.

Secondly, the poll has an option "Send beginners to the Center for Applied Rationality" (spelled "Modern" not "Applied" in the poll because I was unaware that CFMR changed it's name to CFAR).

If trending towards the mean wasn't explicitly mentioned in the poll this would be a useful contribution. As it stands, you should pay a lol toll.

In my experience, which admittedly comes from sites quite different from LW, an Internet project running on volunteer contributions that's decided to keep new members from productive roles has a useful lifetime of no more than one to two years. That's about how long it takes for everybody to voice their pet issues, settle their feuds, and move on with their lives; people may linger for years afterwards, but at that point the vital phase is over. This can be stretched somewhat if there's deep factional divisions within the founding population -- spite is a pretty good motivator -- but only at the cost of making the user experience a lot more political.

It's also worth bearing in mind that demand for membership in a forum like this one is continuous and fairly short-term. Accounts offer few easily quantifiable benefits to begin with, very few if the site's readable to non-members, so we can't rely on lasting ambitions to participate; people sign up because they view this forum as an attractive place to contribute, but the Internet offers no shortage of equivalent niches.

Added for completeness (I'm not sure immigration restrictions are a good idea): Have an invitation system.

Option 1: Close the borders. It's unfortunate that the best sort might be kept out, while its guaranteed the rest will be kept out. The best can found / join other sites, and LW can establish immigration policies after a while.

This isn't so ridiculous in short bursts. I know that Hacker News disables registration if/when they get large media attention to avoid a swathe of new only-mildly-interested users. A similar thing could happen here. (It might be enough to have an admin switch that just puts a display: hidden into the CSS for the "register" button; trivial inconveniences and all.)

LW can establish immigration policies after a while.

Since this started out with people complaining about others already here, we might be called upon to create an immigration police. You sir, show me your +500 karma badge!

Weight each member's upvotes in a manner determined by the proportion of their votes in each direction and their total karma.

You're focusing on negative reinforcement for bad comments. What we need is positive reinforcement for good comments. Because there are so many ways for a comment to be bad, discouraging any given type of bad comment will do effectively nothing to encourage good comments.

"Don't write bad posts/comments" is not what we want. "Write good posts/comments" is what we want, and confusing the two means nothing will get done.

Why do the first three questions have four variations on the theme of "new users are likely to erode the culture" and nothing intermediate between that and "there is definitely no problem at all"?

Why ask for the "best solution" rather than asking "which of these do you think are good ideas"?

It's the Center for Applied Rationality, not Modern Rationality.

Proposed solution: add lots of subdivisions with different requirements.

...some other cause?

I assign non-neglible probability to some cause that I not am not specifically aware of (sorta, but not exactly an outside context problem) having a negative impact on LW's culture.