trentmkelly/LessWrong-43k huggingface dataset:
'oy, girls on lw, want to get together some time?'
by MBlume — 2009-10-02T10:50:11.836Z

2:45:24 PM Katja Grace: The main thing that puts me off in online dating profiles is lack of ambition to save the world
2:45:35 PM Katja Grace: Or do anything much
2:48:03 PM Michael Blume: *nods*
2:48:07 PM Michael Blume: this is indeed a problem
2:57:55 PM Katja Grace: Maybe there is a dating site for smart ambitious nerds somewhere
2:58:25 PM Katja Grace: Need to set up lw extension perhaps
2:59:02 PM Michael Blume: haha, yes ^^
3:00:40 PM Katja Grace: Plenty of discussion on why few girls, how to get girls, nobody ever says 'oy, girls on lw, want to get together some time?'
3:01:14 PM Michael Blume: somebody really should say that
3:01:34 PM Michael Blume: hell, I'm tempted to just copy that IM into a top-level post and click 'submit'
3:01:48 PM Katja Grace: Haha dare you to
Scott Aaronson on Born Probabilities
by Wei Dai — 2009-10-02T06:40:11.245Z

This post attempts to popularize some of Scott Aaronson's lectures and research results relating to Born probabilities. I think they represent a significant step towards answering the question "Why Born's rule?" but do not seem to be very well known. Prof. Aaronson writes frequently on his popular blog, Shtetl-Optimized, but is apparently too modest to use it to do much promotion of his own ideas. I hope he doesn’t mind that I take up this task (and that he forgives any errors and misunderstandings I may have committed here).

Before I begin, I want to point out something that has been bugging me about the fictional Ebborian physics, which will eventually lead us to Aaronson's ideas. So, let’s first recall the following passage from Eliezer’s story:

"And we also discovered," continues Po'mi, "that our very planet of Ebbore, including all the people on it, has a four-dimensional thickness, and is constantly fissioning along that thickness, just as our brains do. Only the fissioned sides of our planet do not remain in contact, as our new selves do; the sides separate into the fourth-dimensional void."

…

"Well," says Po'mi, "when the world splits down its four-dimensional thickness, it does not always split exactly evenly. Indeed, it is not uncommon to see nine-tenths of the four-dimensional thickness in one side."

...

"Now," says Po'mi, "if fundamental physics has nothing to do with consciousness, can you tell me why the subjective probability of finding ourselves in a side of the split world, should be exactly proportional to the square of the thickness of that side?"

Ok, so the part that’s been bugging me is, suppose an Ebborian world splits twice, first into 1/3 and 2/3 of the original thickness (slices A and B respectively), then the B slice splits exactly in half, into two 1/3 thickness slices (C and D). Before the splitting, with what probability should you anticipate ending up in the slices A, C and D? Well, according to the squaring rule, you have 1/5 chance of ending up in A, and 4/5 chance of ending up in B. Those in B then have equal chance of ending up in C and D, so each of them gets a final probability of 2/5.

Well, that’s not how quantum branching works! There, the probability of ending up in any branch depends only on the final amplitude of that branch, not on the order in which branching o

...
Dominant characters on the left
by KatjaGrace — 2009-10-01T22:40:53.000Z

From Psyblog:

Research finds that people or objects moving from left to right are perceived as having greater power (Maass et al., 2007):

Soccer goals are rated as stronger, faster, even more beautiful when the movement of the scorer is from left to right, rather than right to left.

Film violence seems more aggressive, more painful and more shocking when the punch is delivered from left to right, compared with right to left.

Cars in an advert are rated as stronger and faster when they are moving from left to right, rather than right to left (take note advertising executives!).

Perhaps it’s no coincidence that athletes, cars and horses are all usually shown on TV reaching the finishing line from left to right.

According to other studies mentioned by Maass et al, in Western societies most people also tend to preferentially imagine events evolving from left to right, picture the situations in subject-verb-object sentences with the subject on the left of the object, look at new places rather than old ones more when stimuli show up in a left to right order, memorize the final positions of objects further along the implied path more when they are moving left to right, imagine number lines and time increasing from left to right, and scan their eyes over art in a left to right trajectory.

Why is this?

It seems likely that this left to right bias has its roots in language… people who speak languages written from right to left like Arabic or Urdu … display the same bias, but in the opposite direction.

So Maass and the others guessed that characters perceived as more active would also tend to be depicted on the left of more passive characters in pictures. Their research agreed:

We propose that spatial imagery is systematically linked to stereotypic beliefs, such that more agentic groups are envisaged to the left of less agentic groups. This spatial agency bias was tested in three studies. In Study 1, a content analysis of over 200 images of male–female pairs (including artwork, photographs, and cartoons) showed that males were over-proportionally presented to the left of females, but only for couples in which the male was perceived as more agentic. Study 2 (N = 40) showed that people tend to draw males to the left of females, but only if they hold stereotypic beliefs that associate males with greater agency. Study 3 (N = 61) investigated whethe

...
Why Don’t We Apply What We Know About Twins to Everybody Else?
by MichaelGR — 2009-10-01T16:23:42.085Z

I think our intuition might be miscalibrated when it comes to evaluating how much a person’s genes impact how they turn out physically (which isn’t surprising). What’s a bit strange is that we seem to be closer to the truth when it comes to twins.

Nobody’s surprised when identical twins turn out to have very similar bodies (weight, muscle mass, etc), even into adulthood.

But when it comes to non-twins, people seem to think that “making the right choices” and “willpower” are primary factors in how human bodies turn out, and that we can assign a good amount of personal credit or blame to individuals for good and bad outcomes.

There is a disconnect between these two visions, and I think that it’s the latter that needs to be updated.

After all, even if we put aside the direct ways in which our genes build our bodies (encoding how our tissues grow) and instead look at our abilities to “make the right choices” and exert “willpower”, we find that those are also greatly determined by genetic factors. Identical twins probably turn out very similar in good part because they have almost identical amounts of those qualities of mind.

This doesn’t mean that all is pre-determined and that if we all stop trying we’ll turn out the same we would have otherwise, but rather that we are playing within certain parameters, and that the part we control is probably smaller than most people think (not non-existent — we still deserve some credit — just more modest).

To be clear, I’m not saying the situation was white and we thought it was black, or even that it’s a black & white thing, but rather that most people’s intuition might be the wrong shade of gray. Otherwise, I would think there would be a bigger variation between identical twins, but they spend their lives making different choices yet most stay very similar to each other (as far as I know — if you know of a study on this, please send it my way).
Regular NYC Meetups
by MBlume — 2009-10-01T12:44:38.676Z

Sayeth Jasen:

This is an excellent opportunity to announce that I recently organized an OB/LW discussion group that meets in NYC twice a month. We had been meeting sporadically ever since Robin's visit back in April. The regular meetings only started about a month ago and have been great fun. Here is the google group we've been using to organize them:

http://groups.google.com/group/overcomingbiasnyc

We meet every 2nd Saturday at 11:00am and every 4th Tuesday at 6:00pm at Georgia's Bake Shop (on the corner of 89th street and Broadway). The deal is that I show up every time and stay for at least two hours regardless of whether or not anyone else comes.

I've been meaning to post this for a while but I don't have enough Karma...

A couple thoughts:

We're trying to build a community here, and meetups are wonderful, wonderful things. I would recommend that you all follow Jasen's excellent example and see whether OB/LW meetups are happening in your area, and if not, what you can do about that. I'd even suggest an if-you-build-it-they-will-come mentality. We don't really know how many voiceless readers there are for each active commenter. Even if you know of no other LW commenters in your area, try making an announcement that you'll be at such-and-such a place and see what happens.

The karma system is all well and good, but if you have something of high, obvious value on your hands, like, say, regular LW meetups in a major city, you should feel absolutely free to pester one of us high-karma folk (we live in a convenient bar off to the side) to post it on your behalf. It seems plausible that there should also be a monthly thread in which low-karma folk can post these things as comments and high-karma folk can repost them as top-level posts. What say we?
NY-area OB/LW meetup Saturday 10/3 7 PM
by MBlume — 2009-09-30T23:52:52.381Z

Since lots of us anticipate being in New York this weekend for Singularity Summit 2009, it seems like a great time to hold a NY-area Overcoming Bias/Less Wrong meetup! Whether you're attending the summit or not, do consider dropping by the 92nd Street Marriott any time after 7PM, where you will find a lively group of rationalists discussing and dissecting the day's events, and the ideas presented by the summit speakers. We'll be meeting in the hotel's internal restaurant, which should be open until well after midnight.

RSVP at the Facebook Group or see this event in Google Calendar.
Intuitive differences: when to agree to disagree
by Kaj_Sotala — 2009-09-29T07:56:47.836Z

Two days back, I had a rather frustrating disagreement with a friend. The debate rapidly hit a point where it seemed to be going nowhere, and we spent a while going around in circles before agreeing to change the topic. Yesterday, as I was riding the subway, things clicked. I suddenly realized not only what the disagreement had actually been about, but also what several previous disagreements we'd had were about. In all cases, our opinions and arguments had been grounded in opposite intuitions:

Kaj's intuition. In general, we can eventually learn to understand a phenomenon well enough to create a model that is flexible and robust. Coming up with the model is the hard part, but once that is done, adapting the general model to account for specific special cases is a relatively straightforward and basically mechanical process.

Friend's intuition. In general, there are some phenomena which are too complex to be accurately modeled. Any model you create for them is bristle and inflexible: adapting the general model to account for specific special cases takes almost as much work as creating the original model in the first place.

You may notice that these intuitions are not mutually exclusive in the strict sense. They could both be right, one of them covering certain classes of things and the other the remaining ones. And neither one is obviously and blatantly false - both have evidence supporting them. So the disagreement is not about which one is right, as such. Rather, it's a question of which one is more right, which is the one with broader applicability.

As soon as I realized this, I also realized two other things. One, whenever we would run into this difference in the future, we'd need to recognize it and stop that line of debate, for it wouldn't be resolved before the root disagreement had been solved. Two, actually resolving that core disagreement would take so much time and energy that it probably wouldn't be worth the effort.

The important thing to realize is that neither intuition rests on any particular piece of evidence. Instead, each one is a general outlook that has been formed over many years and countless pieces of evidence, most of which have already been forgotten. Before my realization, neither of us had even consciously known they existed. They are abstract patterns our minds have extracted from what must be hundreds of different cases we've enc...
Why Many-Worlds Is Not The Rationally Favored Interpretation
by Mitchell_Porter — 2009-09-29T05:22:48.366Z

Eliezer recently posted an essay on "the fallacy of privileging the hypothesis". What it's really about is the fallacy of privileging an arbitrary hypothesis. In the fictional example, a detective proposes that the investigation of an unsolved murder should begin by investigating whether a particular, randomly chosen citizen was in fact the murderer. Towards the end, this is likened to the presumption that one particular religion, rather than any of the other existing or even merely possible religions, is especially worth investigating.

However, in between the fictional and the supernatural illustrations of the fallacy, we have something more empirical: quantum mechanics. Eliezer writes, as he has previously, that the many-worlds interpretation is the one - the rationally favored interpretation, the picture of reality which rationally should be adopted given the empirical success of quantum theory. Eliezer has said this before, and I have argued against it before, back when this site was just part of a blog. This site is about rationality, not physics; and the quantum case is not essential to the exposition of this fallacy. But given the regularity with which many-worlds metaphysics shows up in discussion here, perhaps it is worth presenting a case for the opposition.

We can do this the easy way, or the hard way. The easy way is to argue that many-worlds is merely not favored, because we are nowhere near being able to locate our hypotheses in a way which permits a clean-cut judgment about their relative merits. The available hypotheses about the reality beneath quantum appearances are one and all unfinished muddles, and we should let their advocates get on with turning them into exact hypotheses without picking favorites first. (That is, if their advocates can be bothered turning them into exact hypotheses.)

The hard way is to argue that many-worlds is actually disfavored - that we can already say it is unlikely to be true. But let's take the easy path first, and see how things stand at the end.

The two examples of favoring an arbitrary hypothesis with which we have been provided - the murder investigation, the rivalry of religions - both present a situation in which the obvious hypotheses are homogeneous. They all have the form "Citizen X did it" or "Deity Y did it". It is easy to see that for particular values of X and Y, one is making an arbitrary selection f...
Privileging the Hypothesis
by Eliezer Yudkowsky — 2009-09-29T00:40:12.159Z

Suppose that the police of Largeville, a town with a million inhabitants, are investigating a murder in which there are few or no clues—the victim was stabbed to death in an alley, and there are no fingerprints and no witnesses.

Then, one of the detectives says, “Well… we have no idea who did it… no particular evidence singling out any of the million people in this city… but let’s consider the hypothesis that this murder was committed by Mortimer Q. Snodgrass, who lives at 128 Ordinary Ln. It could have been him, after all.”

I’ll label this the fallacy of privileging the hypothesis. (Do let me know if it already has an official name—I can’t recall seeing it described.)

Now the detective may perhaps have some form of rational evidence that is not legal evidence admissible in court—hearsay from an informant, for example. But if the detective does not have some justification already in hand for promoting Mortimer to the police’s special attention—if the name is pulled entirely out of a hat—then Mortimer’s rights are being violated.

And this is true even if the detective is not claiming that Mortimer “did” do it, but only asking the police to spend time pondering that Mortimer might have done it—unjustifiably promoting that particular hypothesis to attention. It’s human nature to look for confirmation rather than disconfirmation. Suppose that three detectives each suggest their hated enemies, as names to be considered; and Mortimer is brown-haired, Frederick is black-haired, and Helen is blonde. Then a witness is found who says that the person leaving the scene was brown-haired. “Aha!” say the police. “We previously had no evidence to distinguish among the possibilities, but now we know that Mortimer did it!”

This is related to the principle I’ve started calling “locating the hypothesis,” which is that if you have a billion boxes only one of which contains a diamond (the truth), and your detectors only provide 1 bit of evidence apiece, then it takes much more evidence to promote the truth to your particular attention—to narrow it down to ten good possibilities, each deserving of our individual attention—than it does to figure out which of those ten possibilities is true. It takes 27 bits to narrow it down to ten, and just another 4 bits will give us better than even odds of having the right answer.

Thus the detective, in calling Mortimer to the particular attention of... ,
Your Most Valuable Skill
by Alicorn — 2009-09-27T17:01:10.306Z

Knowledge is great: I suspect we can agree there. Sadly, though, we can't guarantee ourselves infinite time in which to learn everything eventually, and in the meantime, there are plenty of situations where having irrelevant knowledge instead of more instrumentally useful knowledge can be decidedly suboptimal. Therefore, there's good reason to work out what facts we'll need to deploy and give special priority to learning those facts. There's nothing intrinsically more interesting or valuable about the knowledge that the capital of the United States is Washington, D.C. than there is about the knowledge that the capital of Bali is Denpasar, but unless you live or spend a lot of time in Indonesia, the latter knowledge will be less likely to come up.

It seems the same is true of procedural knowledge (with the quirk that it's easier to deliberately put yourself in situations where you use whatever procedural knowledge you have than it is to arrange to need to know the capital of Bali.) If your procedural knowledge is useful, and also difficult to obtain or unpopular to practice or both, you might even turn it into a career (or save money that you would have spent hiring people who have).

Rationality is sort of the ur-procedure, but after a certain point - the point where you're no longer buying into supernaturalist superstition, begging for a Darwin Award, or falling for cheap scams - its marginal practical value diminishes. Practicing rationality as an art is fun and there's some chance it'll yield a high return, but evolution (genetic and memetic) didn't do that bad of a job on us: we enter adulthood with an arsenal of heuristics that are mostly good enough. A little patching of the worst leaks, some bailing of bilge that got in early on, and you have a serviceable brain-yacht. (Sound of metaphor straining.)

So when you want to spend time on learning or honing a skill, it makes sense to choose skills with a high return on investment, be it in terms of fun, resources, the goodwill of others, insurance against emergency, or other valuable results. Note that if you learned a skill, used it to learn a non-customized fact, and do not anticipate using the skill again, it's not the skill that was useful; the skill was just a sine qua non for the useful fact, and others don't have to duplicate the research process to benefit...
The Anthropic Trilemma
by Eliezer Yudkowsky — 2009-09-27T01:47:54.920Z

Speaking of problems I don't know how to solve, here's one that's been gnawing at me for years.

The operation of splitting a subjective worldline seems obvious enough - the skeptical initiate can consider the Ebborians, creatures whose brains come in flat sheets and who can symmetrically divide down their thickness. The more sophisticated need merely consider a sentient computer program: stop, copy, paste, start, and what was one person has now continued on in two places. If one of your future selves will see red, and one of your future selves will see green, then (it seems) you should anticipate seeing red or green when you wake up with 50% probability. That is, it's a known fact that different versions of you will see red, or alternatively green, and you should weight the two anticipated possibilities equally. (Consider what happens when you're flipping a quantum coin: half your measure will continue into either branch, and subjective probability will follow quantum measure for unknown reasons.)

But if I make two copies of the same computer program, is there twice as much experience, or only the same experience? Does someone who runs redundantly on three processors, get three times as much weight as someone who runs on one processor?

Let's suppose that three copies get three times as much experience. (If not, then, in a Big universe, large enough that at least one copy of anything exists somewhere, you run into the Boltzmann Brain problem.)

Just as computer programs or brains can split, they ought to be able to merge. If we imagine a version of the Ebborian species that computes digitally, so that the brains remain synchronized so long as they go on getting the same sensory inputs, then we ought to be able to put two brains back together along the thickness, after dividing them. In the case of computer programs, we should be able to perform an operation where we compare each two bits in the program, and if they are the same, copy them, and if they are different, delete the whole program. (This seems to establish an equal causal dependency of the final program on the two original programs that went into it. E.g., if you test the causal dependency via counterfactuals, then disturbing any bit of the two originals, results in the final program being completely different (namely deleted).)

So here's a simpl...