trentmkelly/LessWrong-43k huggingface dataset:
Quantum Measurements
by paulfchristiano — 2010-12-19T01:59:24.944Z

Related to: The Quantum Physics Sequence, particular Decoherence is Pointless.

If you really understand quantum mechanics (or the linked post on decoherence) you shouldn't get anything out of this post, but understanding this really cleared things up for me, so hopefully it will clear things up for someone else too.

Here at lesswrong we are probably all good Solomonoff inductors and so tend to reject collapse. We believe that a measurement destroys interference because it entangles some degrees of freedom from a quantum system with its environment. Of course, this process doesn't occur sharply and discontinuously. It happens gradually, as the degree of entanglement is increased. But what exactly does "gradually" mean here? Lets focus on a particular example.

Suppose I run the classic two-slit experiment, but I measure which slit the electron goes through. Of course, I don't observe an interference pattern. What happens if we "measure it less"? Lets go to the extreme: I change the polarization of a single photon depending on which slit the electron went through (its either polarized vertically or horizontally), and I send that photon off to space (where its polarization will not be coupled to any other degrees of freedom). Do I now see just a little bit of an interference pattern?

A naive guess is that strength of the interference pattern drops off exponentially with the number of degrees of freedom entangled with the measurement of which slit the electron went through. In a certain sense, this is completely correct. But if I were to perform the experiment exactly as I described---in particular, if I were to polarize the photon perfectly horizontally in the one case and perfectly vertically in the other case---then I would observe no interference at all. (This may or may not be possible, depending on the way nature chose to implement electrons, photons, and slits. Whether or not you can measure exactly is really not philosophically important to quantum mechanics, and I feel completely confident saying that science doesn't yet know the answer. So I guess I'm not yet decided on whether decoherence really happens "gradually." )

The important thing is that two paths leading to the same state only interfere if they lead to exactly the same state. The two ways for the electron to get to the center of the screen interfere by default because nature has no record of ...
Best of Rationality Quotes 2009/2010
by DanielVarga — 2010-12-18T21:36:38.434Z

Best of Rationality Quotes 2009/2010 (Warning: 750kB page, 774 quotes)

The year's last Rationality Quotes thread has calmed down, so now it is a good time to update my Best of Rationality Quotes page, and write a top post about it. (The original version was introduced in the June 2010 Open Thread.)

The page was built by a short script (source code here) from all the LW Rationality Quotes threads so far. (We had such a thread each month since April 2009.) The script collects all comments with karma score 4 or more, and sorts them by score.

There is a minor complication: The obvious idea is to consider only top-level comments, that is, comments that are not replies to other comments. Unfortunately, good quotes are sometimes replies to other quotes. Of course, even more often, replies are not quotes. This is a precision-recall trade-off. Originally I went for recall, because I liked many replied quotes such as this. But as JGWeissman noted in a comment below, to build the precise version, only a trivial modification of my script is needed. So I built it, and I preferred it to the noisy version after all. So now at the top of this post we have the filtered version, and here is the original version with even more good quotes, but also with many non-quotes:

Best of Rationality Quotes 2009/2010, including replied comments (Warning: 1.3MB page, 1358 quotes)

UPDATE: I changed the links and rewrote the above when I decided to filter replied comments.

UPDATE 2: Added a comment listing the personal quote collection pages of top quote contributors.

UPDATE 3: Responding to various requests by commenters, added several top-lists:

Top quote contributors by total karma score collected

Top quote contributors by average score of quotes

Top quote contributors by statistical significance level

Top original authors by number of quotes

Top original authors by total karma score collected
How Pascal's Wager Saved My Soul
by SRStarin — 2010-12-18T20:47:00.809Z

[I know Pascal's Wager isn't a hard logical problem for a Bayesian to tackle. However, please read the following account of how it helped me become more rational.]

I was a Christian when I was a boy. I believed in the miraculous birth and resurrection of Christ, heaven and hell, God on high answering prayers, and so on and so forth. I also believed in Santa Claus. When I stopped believing in Santa Claus when I was 9, my faith in the other stuff I'd been told was somewhat shaken, but I got over it, as I was told that everyone did.

When I was 15, I went to a summer program for weird kids (i.e. nerds) called Governor's School. Each week at Governor's School, the entire group of us was addressed by a pencil-necked, jaded philosophy professor called Dr. Bob. (Full disclosure: I am a jaded and pencil-necked person myself.) One week late in the summer, after he'd gotten our trust with other Astounding Insights, he told us about Pascal's Wager, concluding that we should all be Christians. And he left it at that.

We all found this very strange, as Dr. Bob had seemed rather unfriendly to religion before without ever having said anything outright irreligious. In fact, I didn't like him very much because I believed in the Lord Jesus Christ, and I didn't entirely like being forced to think about that belief too much. But Pascal's Wager was too much: I had always just believed because I'd been told by trustworthy people to believe, and here was this guy I didn't like saying I had to believe.

So, I couldn't get it out of my mind. You all know Pascal's Wager (and even have Yudkowski's Pascal's Mugging to boot), but I'm going to take it apart the way 15-year-old Scott did:

I thought: "If Heaven and Hell are real, then it would be best for me if I believed in them. If they aren't real, it wouldn't hurt for me to believe in them, because we're all just dead anyway, in the end. That's straightforward enough."

I objected: "But God doesn't just want our belief in Heaven or Hell, I thought. He wants our love and devotion. Heaven and Hell are just ways of getting Kohlberg 3's and lower to go to church and learn the right way of believing (Another thing we'd all learned by that point was the Kohlberg stages.) Like using Santa Claus giving gifts at Christmas to keep little kids good."

I recalled my 10th Christmas: Ohhhhhh.

I stopped believing in God.

Truth is the thing we need to know to ...
When and how psychological data is collected affects the kind of students who volunteer
by Kaj_Sotala — 2010-12-18T13:41:43.455Z

http://bps-research-digest.blogspot.com/2010/12/when-and-how-psychological-data-is.html

Psychology has a serious problem. You may have heard about its over-dependence on WEIRD participants - that is, those from Western, Educated, Industrialised, Rich Democracies. More specifically, as regular readers will be aware, countless psychology studies involve undergraduate students, particularly psych undergrads. Apart from the obvious fact that this limits the generalisability of the findings, Edward Witt and his colleagues provide evidence in a new paper for two further problems, this time involving self-selection biases.
Just over 500 Michigan State University undergrads (75 per cent were female) had the option, at a time of their choosing during the Spring 2010 semester, to volunteer either for an on-line personality study, or a face-to-face version. The data collection was always arranged for Wednesdays at 12.30pm to control for time of day/week effects. Also, the same personality survey was administered by computer in the same way in both experiment types, it's just that in the face-to-face version it was made clear that the students had to attend the research lab, and an experimenter would be present.
Just 30 per cent of the sample opted for the face-to-face version. Predictably enough, these folk tended to score more highly on extraversion. The effect size was small (d=-.26) but statistically significant. Regards more specific personality traits, the students who chose the face-to-face version were also more altruistic and less cautious.
What about choice of semester week? As you might expect, it was the more conscientious students who opted for dates earlier in the semester (r=.-.20). What's more, men were far more likely to volunteer later in the semester, even after controlling for average personality difference between the sexes. For example, 18 per cent of week one participants were male compared with 52 per cent in the final, 13th week.
In other words, the kind of people who volunteer for research will likely vary according to the time of semester and the mode of data collection. Imagine you used false negative feedback on a cognitive task to explore effects on confidence and performance. Participants tested at the start of semester, who are typically more conscientious and motivated, are likely to be affected in a different way than participants who volu

...
An Intuitive Explanation of Eliezer Yudkowsky’s Intuitive Explanation of Bayes’ Theorem
by Alexandros — 2010-12-18T13:26:18.180Z

Common Sense Atheism has recently had a string of fantastic introductory LessWrong related material. First easing its audience into the singularity, then summarising the sequences, yesterday affirming that Death is a Problem to be Solved, and finally today by presenting An Intuitive Explanation of Eliezer Yudkowsky’s Intuitive Explanation of Bayes’ Theorem.

From the article:

Eliezer’s explanation of this hugely important law of probability is probably the best one on the internet, but I fear it may still be too fast-moving for those who haven’t needed to do even algeba since high school. Eliezer calls it “excruciatingly gentle,” but he must be measuring “gentle” on a scale for people who were reading Feynman at age 9 and doing calculus at age 13 like him.

So, I decided to write an even gentler introduction to Bayes’ Theorem. One that is gentle for normal people.

It may be interesting if you want to do a review of Bayes' Theorem from a different perspective, or offer some introductory material for others. From a wider viewpoint, it's great to see a popular blog joining our cause for raising the sanity waterline.
Cryptographic Boxes for Unfriendly AI
by paulfchristiano — 2010-12-18T08:28:45.536Z

Related to: Shut up and do the impossible!; Everything about an AI in a box.
One solution to the problem of friendliness is to develop a self-improving, unfriendly AI, put it in a box, and ask it to make a friendly AI for us. This gets around the incredible difficulty of developing a friendly AI, but it creates a new, apparently equally impossible problem. How do you design a box strong enough to hold a superintelligence? Lets suppose, optimistically, that researchers on friendly AI have developed some notion of a certifiably friendly AI: a class of optimization processes whose behavior we can automatically verify will be friendly. Now the problem is designing a box strong enough to hold an unfriendly AI until it modifies itself to be certifiably friendly (of course, it may have to make itself smarter first, and it may need to learn a lot about the world to succeed).

Edit: Many people have correctly pointed out that certifying friendliness is probably incredibly difficult. I personally believe it is likely to be significantly easier than actually finding an FAI, even if current approaches are more likely to find FAI first. But this isn't really the core of the article. I am describing a general technique for quarantining potentially dangerous and extraordinarily sophisticated code, at great expense. In particular, if we developed uFAI before having any notion of certifiable friendliness, then we could still use this technique to try and use the uFAI in a very limited way. It allows us to quarantine an AI and force everything it tries to say to us through an arbitrarily complicated filter. So, for example, if we are interested in solving some problem with a unique and verifiably correct answer, then we can ask the AI for this answer and only see the output if it passes the verification. We can also use a quarantined AI in more useful ways, at the expense of introducing some limited channels of influence (for example, if we ask for the solution to a problem which may have several solutions, we allow the AI to influence us by choosing which solution to provide)

Minimally, I hope this scheme at least suggests that putting an AI in a box may not be catastrophic. What to do with a boxed AI is another question. /Edit.

Concretely, suppose someone comes to you with the design of a recursively self-improving AI---call it Hal. Unfortunately, Hal is not ce...
Brain blogger survey
by NancyLebovitz — 2010-12-18T02:40:39.146Z

Survey info

:

I’m currently doing some research on brain bloggers. The first stage is a rather basic survey (below). This is open from today until Monday the 10th of January.

By ‘brain bloggers’ I mean bloggers who write about the stuff that goes in people’s heads, whatever we think this stuff is. Such bloggers might focus on neurology or psychology, or another field entirely. It might be the history, anthropology or commercial applications of these fields. It might come under ‘research blogging’, journalism, ‘public engagement’ or some form of political activism (or several of these at once, or something else entirely). This focus might be exclusively brain-y, or brain-ish issues might be topics they occasionally blog about in the course of other work.
Link: Facing the Mind-Killer
by Larks — 2010-12-18T00:57:08.114Z

I've long opposed discussing politics on Less Wrong. Elsewhere, however, I have been known to gaze into the abyss; and so it came to be that I wrote a handful of blog posts of the Oxford Libertarian Society Blog. I had the deliberate intention of bring a little bit of rationality into politics - and so of course ended up writing in something like Eliezer's style.

I wanted to establish some theory first, so the initial posts were about The Conservation of Expected Evidence and Reductionism, and then one particular Death-Spiral.

As you'll probably notice, one of my defences against the little-death has been to err on the side of attacking Libertarian positions; I provided an account of Traditional Socialist Values so we remember that our enemies aren't inherently evil, and then analysed an abuse of The Law of Comparative Advantage, showing cases where it didn't apply.

I can't promise I'll update at all regularly.

Post inspired by Will Newsome and prompted by Vladimir Nesov.

http://oxlib.blogspot.com/
Folk grammar and morality
by Emile — 2010-12-17T21:20:46.169Z

If you've spent any time with foreigners learning your language, you may have been in conversations like this:

Mei: I'm a bit confused ... what's the difference between "even though" and "although"?

Albert: Um, I think they're mostly equivalent, but "even though" is a bit more emphatic.

Barry: Are you sure ? I remember something about one being for positives, and the other for negatives. For example, let's see, these sentences sound a bit weird:"He refused to give me the slightest clue, although I begged on my knees", and "Although his car broke down on the first mile, he still won the rally".

People can't automatically state the rules underlying language, even though they follow them perfectly in their daily speech. I've been made especially aware of this when teaching French to Chinese students, where I had to frequently revise my explanation, or just say "sorry, I don't know what the rule is for this case, you'll just have to memorize it". You learn separately how to speak the language and how to apply the rules.

Morality is similar: we feel what's wrong and what's right, but may not be able to formulate the underlying rules. And when we do, we're likely to get it wrong the first time. For example you might say:

It has been suggested that animals have less subjective experience than people. For example, it would be possible to have an animal that counts as half a human for the purposes of morality.

But unlike grammar, people don't always agree on right and wrong : if Alfred unintentionally harms Barry, Barry is more likely to think that what Alfred did was morally wrong, even if both started off with similar moral intuitions. So if you come up with an explanation and insist it's the definition of morality, you can't be "proven wrong" nearly as easily as on grammar. You may even insist your explanation is true, and adjust your behavior accordingly, as some religious fanatics seem to do ("what is moral is what God said" being a quite common rule people come up with to explain morality).

So: beware of your own explanations. Morality is a complex topic, you're even more likely to shoot yourself in the foot than with grammar, and even less likely to realize that you're wrong.

(edit) Related posts by Eliezer: Fake Justification, Fake Selfishness, Fake Morality.
Turing Test Tournament For Funding
by Strange7 — 2010-12-17T18:53:15.242Z

It's always troubled me that the standard Turing test provides only a single-bit output, and that the human being questioned could throw the game to make their AI counterpart look good. Also, research and development gets entirely too much funding based on what sounds cool rather than what actually works. The following is an attempt to address both issues.

Take at least half a dozen chatbot AIs, and a similar number of humans with varying levels of communication skill (professional salespeople, autistic children, etc.). Each competitor gets a list of questions. A week later, to allow time for research and number-crunching, collect the answers. Whoever submitted question 1 receives all the answers to question 1 in a randomized order, and then ranks the answers from most human/helpful to least, with a big prize for the top and successively smaller prizes for runners-up. Alternatively, interrogators could specify a customized allocation of their question's rewards, e.g. "this was the best, these three are tied for second, the rest are useless."

The humans will do their best in that special way that only well-paid people can, and the chatbots will receive additional funding in direct proportion to their success at a highly competitive task.

Six hundred thousand seconds might seem like an awfully long time to let a supercomputer chew over it's responses, but the goal is deep reasoning, not just snappy comebacks. Programs can always be debugged and streamlined, or just run on more powerful future hardware, after the basic usefulness of the results has been demonstrated.
TrailMemes for Sequences
by drc500free — 2010-12-17T17:08:02.121Z

One of the obstacles I faced when first confronted with the Sequences was figuring out the prerequisites for any given post. At times this is spelled out explicitly, but there are many parallel paths and cross-referencing. Another problem was that posts don't link forward to the posts that reference them.

TrailMeme lets you "blaze a trail" through a mass of blog posts by creating a directed graph, which other users can then "walk." The site is still in Beta, and can be unstable at times.

I tried to more or less follow the posted pre-requisites and link-backs, but culled a lot of the redundant ones to reduce confusion. I found one pre-existing trail, and invite anyone with free time to contribute! Trails so far:

Mysterious Answers to Mysterious Questions

A Human's Guide to Words

Reductionism

Map and Territory

Politics is the Mind-Killer
Weirdtopias in science fiction
by NancyLebovitz — 2010-12-17T13:58:02.394Z

There's "Day Million" and The Age of the Pussyfoot, both by Frederik Pohl, and even they might be more like utopias rather than adequately weird.

"Day Million" is a very short story, with a narration which puts emphasis on how much people like living in that world even though it would make little sense to a contemporary reader. Unfortunately, the most vivid detail is a spoiler. N pbhcyr (obgu bs jubz jbhyq frrz bqq, gubhtu bar'f pyrneyl znyr naq gur bgure'f pyrneyl srznyr ner nggenpgrq gb rnpu bgure-- gurl unir n tbbq gvzr bapr, naq gura qb jung'f abezny va gung phygher-- rkpunatr vqragvgl gncrf

Silverberg's The World Inside might count.

It a description of how people might be pretty happy living in a maximum population world.

R.A. Lafferty's Slow Tuesday Night is a weirdtopia, and so is his Primary Education of the Camiroi. Unfortunately, his "Polity and Custom among the Camiroi" is incomplete at google books, but I recommend getting a paper copy of Nine Hundred Grandmothers-- the collection has some of his best work.

gwern supplied the link for Polity and Custom:

No assembly on Camiroi for purposes of entertainment may exceed thirty-nine persons. No more than this number may witness any spectacle or drama, or hear a musical presentation, or watch a sporting event. This is to prevent the citizens from becoming mere spectators rather than originators or partakers. Similarly, no writing -- other than certain rare official promulgations -- may be issued in more than thirty-nine copies in one month. This, it seems to us, is a conservative ruling to prevent popular enthusiasms. A father of a family who twice in five years appeals to specialists for such things as simple surgery for members of his household, or legal or financial or medical advice, or any such things as he himself should be capable of doing, shall lose his citizenship. It seems to us that this ruling obstructs the Camiroi from the full fruits of progress and research.

"Slow Tuesday Night" is a whimsy about people who've had a mental stutter removed-- they live so fast that they can have three careers in eight hours. "Primary Education Among the Camiroi" is about a culture which develops maximum intelligence and self-reliance, at the cost of a few of the children being killed. It teaches slow reading (reading slowly enough that everything is remembered), and the world government course consists ...