Posts

LessWrong IQ Survey 2012-12-02T21:53:58.993Z
Challenge: change someone's mind 2012-07-18T19:06:55.052Z
How to read a book 2012-06-27T01:31:14.685Z
Personality analysis in terms of parameters 2012-06-20T11:51:40.861Z
Looking for an intuitive explanation of expected outcome 2012-06-20T01:33:45.560Z
A few questions about Discussion 2012-06-19T23:50:46.523Z

Comments

Comment by Blackened on Harry Potter and the Methods of Rationality discussion thread, part 19, chapter 88-89 · 2013-07-04T17:44:56.717Z · LW · GW

I will throw in several predictions. I myself am not completely confident of some of those.

  1. Time-turners, prophecies and similar devices, which predict that something will happen, work by exerting some mind control upon people in the form of unexplicable urges, such as the urge to take the left turn this one time. I'm not sure how far can they go in order to fulfill themselves.

  2. The events in the magical world are not just dictated by the already-discovered laws of physics, but also by the laws of fairy tales. Dumbledore is pretty damn rational, at many points more rational than Harry (he might even be more rational overall). His reasons for having an evil Potions master aren't simply because this happens in fairy tales. The Universe liked it more if that was the case, so he was probably represented with an evil person who is highly suitable for the Potions position, or something like that. Dumbledore is most probably aware of this law. After Harry case the true Patronus and Quirrell asked him where he'd hide something, Harry gives 5 places: volcano, inside earth, deep in the ocean, somewhere in the air, and in space. Fire, Earth, Water, Air, space-thingy. He can't have said that by coincidence, and this is evidence of that law existing. Quirrell's reaction indicates he's aware of the law.

  3. Part of Voldemort is in Harry. The Sorting Hat either lied, or more likely, Voldemort isn't in his scar - Harry asked about his scar (I realized that much before it was reminded in chapter 90 or 91 and therefore have read a lot of HPMOR with that in mind), but it may still be inside Harry, just not in the scar. Evidence: his unusual 26-hour sleep cycle was probably inherited; he is exceptionally intelligent, and just 11, while his parents aren't particularly intelligent (intelligence is usually mostly inherited genetically); he is better with a broomstick than children who have used broomsticks before going to Hogwarts; his dark side seeks destruction (Voldemort appears to seek destruction too), and is very cold (from his flashback, Voldemort's voice is really quite cold). This probably happened by accident, rather than as a plot - it may be explained with the law from 2. - Voldemort tried to kill Harry, the universe interfered in the simplest possible way, although I'm surprised as to why did the universe let Voltemort find Harry in the first place then.

  4. Quirrell is not Voldemort. I'm still very perplexed by Quirrell, but it would make an awful, predictable plot to have him be Voldemort. He does appear to be a Dark wizard, the Monroe story seems implausible (he doesn't believe in others' love, why would he be a hero? Unless he did that for himself). He probably has a lot to do with Voldemort, but they were neither friends nor enemies. I don't know about the sense of doom, but it probably is connected with what happened when Harry's parents died. It appears that Quirrell doesn't know about it, either - therefore it is probably because he could not see an explanation, because the explanation involves love, and isn't obvious.

  5. Voldemort is the one who will (at least try to) TEAR APART THE VERY STARS FROM HEAVEN. He seems to be all about destruction, though I'm not sure why, and I'm not sure why does he not take the shortcuts Harry had in mind, and this is the weak part of this prediction. Perhaps it is the universe's will that people must die for a good reason, rather than having the world's strongest wizards destroyed by a handful of highly toxic molecules each.

  6. Magic is like that because it is made by humans. This is probably obvious - magic came to exist by humans, this is why a lot of it only make sense in terms of human intuitions, and not so much sense in terms of laws of physics. I'm still very puzzled by the fact that it appears to violate the laws of physics. It also sounded like magic might be a superintelligent AI, but I forgot my arguments for that.

I also wonder, what would happen if you use a time-turner to do the impossible, for example talk to your older copy, so when you see the newer copy, don't time-turn. Would it turn out that someone strongly felt like approaching you while Polyjuiced as you? Is it that nobody would ever think of that in the wizarding world? I'm sure there's a lot more going on with time-turners.

Comment by Blackened on Harry Potter and the Methods of Rationality discussion thread, part 19, chapter 88-89 · 2013-07-01T01:28:28.852Z · LW · GW

I'm surprised to see everyone overlook the most obvious possibility: Voldemort.

Point one: The earlier prophecy was probably about the same person, and he hadn't arrived yet at the moment. Even if it was about something different. 'he has come' in the last prophecy implies that he had just arrived.

Point two: Voldemort appears to love destruction. I still don't know how someone as intelligent as him hadn't killed everyone in the ways Harry thought of -. Harry's intent to kill, which is presumably very Voldemort-like, is extremely creative and effective even at his magic level and age. But assuming that Voldemort is about destruction, he might want to end the world.

Quirrell or someone (e.g. Snape) might have resurrected Voldemort right after stealing the Philosopher's Stone - a time-turner may be involved.. Dumbledore was away, Snape might be unreliable, it could have easily happened. A counterindicator is that Dumbledore is probably also aware of this risk, and therefore might have taken counter-measurements, although we can see that Quirrell can fool him in the part where he learns about the zoomagus potion left in Bellatrix's cell (though it portrays himself and Snape as significantly inferior to Voldemort and Quirrell, so I'm reluctant to believe it was real, rather than them acting in front of McGonagall).

Comment by Blackened on What are your rules of thumb? · 2013-02-19T15:39:32.298Z · LW · GW
  • If something sounds certainly correct, check it up on Wikipedia anyway - it takes less than a minute. Likewise if it sounds almost certainly wrong.
  • If I don't know why exactly someone went to his conclusion, do not assume he thinks it for the wrong reasons.
  • If I can predict I will be too busy to go to gym in the next few days, do a 5-minute (1-set) exercise - this is at least 50% of the efficiency of a normal exercise.
  • When I feel the drive to argue, do careful judgement on whether it's efficient to do so.
  • Never blame people for their biases. If they don't understand me, and even if they are trying not to understand me, blaming the people is meaningless. It is my fault that I could not predict them and was not persuasive. Furthermore, such people are usually kind and not even being unintentionally mean, no matter how bad are the results of their actions (this also applies to extreme cases of biasedness, such as outgroup thinking).
  • Don't ignore the judgement of people that appear to be basing their opinion on anecdotal evidence and are easily biased. They may or may not have a good reason for thinking that. If I don't know how did they reach the conclusion, no matter how absurd their arguments sound, they might be added after the bottom line was drawn, while the bottom line being based on reasonable evidence (this has happened at least once).
Comment by Blackened on Harry Potter and the Methods of Rationality discussion thread, part 18, chapter 87 · 2012-12-31T18:29:17.762Z · LW · GW

It doesn't fit my model of human behavior. But that's possibly just me.

I'd imagine that if Snape got really angry, but it's only because Harry offended him without knowing, well, he wouldn't be close to harming him. I guess it would be appropriate to say "you almost died" if it's not true, but then Harry acted as if Snape might reconsider his decision to not kill him, rather than being just apologetic, or something like that. Or maybe he was indeed, and I am likely to be underestimating the strength of the impact that Harry's words had on Snape.

But if others interpreted it like me, then I got it right. Hmm.

Comment by Blackened on Harry Potter and the Methods of Rationality discussion thread, part 18, chapter 87 · 2012-12-31T18:11:35.044Z · LW · GW

There was something that has always been bugging me. It's actually several things I don't understand.

When Snape says "You almost died today, Potter", what does he mean? Maybe it's because I'm not a native speaker, but I can't understand that part. My best guess is that Snape got so upset with what Harry said that he almost killed him in his rage. But that seems very counterintuitive to me.

Second, Snape had possibly changed after his conversation with Harry? Does this mean that Snape took Harry's words and thought that Lily is actually not worth his love, after all these years? That's my best hypothesis, but I find it very weird.

Third, did I actually properly understood that he still loves her, after more than 11 years have passed? This is very unrealistic, people get over things, and I suspect that either EY is being unrealistic here, or Snape is simply lying.

Edit: I retract the last part. Still, this does not mean that now I believe this to be realistic, but rather that it might possibly be realistic. Also that EY could indeed have decided to just go with the canon, and I see good reasons for that.

Comment by Blackened on Notes on Psychopathy · 2012-12-21T02:20:43.288Z · LW · GW

Edit: Why -karma? Offtopic? :/

I haven't read the whole article, but AFAIK, psychopathy is basically an extremely low level of empathy/compassion (virtually zero). I have always suspected Quirrell of psychopathy.

Comment by Blackened on Harry Potter and the Methods of Rationality discussion thread, part 13, chapter 81 · 2012-12-17T23:14:49.595Z · LW · GW

I'd love to see a list of spoilers about things that were hinted at and reasonably sounding hypotheses, if anyone ever made one. Please do reply to this post with your discoveries and speculations. I'm also going to post mine, once I finish rereading HPMOR.

Comment by Blackened on LessWrong IQ Survey · 2012-12-03T19:41:30.189Z · LW · GW

I did notice the title didn't sound right to me. But I also couldn't find the right words (English isn't my native language). Any suggestions?

Comment by Blackened on LessWrong IQ Survey · 2012-12-03T17:56:42.511Z · LW · GW

It strongly depends on the person, some are faster than others.

JCTI takes at least an hour for nearly all people with high scores. 2-3 hours isn't too much.

CFNSE takes 2 to 5 hours, according to the estimation on the website - it's an accurate estimation IMO. A possible strategy is to do it "quickly" (for 2-5 hours or so) and leave everything you couldn't answer definitely for the last. Then spend 30-60 minutes on each of those. I think this isn't going to artificially inflate your score, and I'm quite certain that someone with 100-110 IQ can't figure out the patterns for any of the hardest questions, even if he spends hours/days on each.

Comment by Blackened on LessWrong IQ Survey · 2012-12-03T10:26:58.483Z · LW · GW

Fortunately, we can still view individual replies.

Comment by Blackened on LessWrong IQ Survey · 2012-12-03T10:24:50.243Z · LW · GW

You are either not understanding, or not wanting to understand, the difference between the score on a reliable IQ test and the SAT scores of just the LWers who took a SAT. Obviously, an IQ test is a much better indicator, also SAT is only available for people in the US. Also, the responses I'm getting are already very different from the survey.

JCTI's reliability is verifiable from the link, even though the other test's is not.

sitting around talking about how smart we are doesn't send signals to onlookers that I think are in the best interests of LessWrong.

Investigating a phenomena is what we are about. I don't see a logically valid reason to not investigate this one, especially if previous data suggests an abnormally high level. This holds true even if the concept of IQ is invalid, as long as it is measurable.

Comment by Blackened on LessWrong IQ Survey · 2012-12-03T10:12:03.372Z · LW · GW

We can still view the individual responses and ignore this one.

Comment by Blackened on LessWrong IQ Survey · 2012-12-03T10:06:04.538Z · LW · GW

Yes. And I thought I reread the thing xD

Comment by Blackened on LessWrong IQ Survey · 2012-12-02T23:46:35.758Z · LW · GW

Ahh. For some reason, I was convinced that the link worked before I edited my post, during the process of which I didn't touch the link. So I just left it there, out of frustration, it was clickable anyway. Fixed.

Maybe HTML does suggest something about LW's IQ, but it is not really useful, given the current evidence we have so far. The way I interpret it, it says that the average IQ is probably over 110-120 (no upper limit), with a quite weak reliability. Even if we don't take into account that 20-70% of the users know programming (many people don't study computer science, but still use programming).

Comment by Blackened on LessWrong IQ Survey · 2012-12-02T23:04:03.354Z · LW · GW

Yes. Edited.

Comment by Blackened on LessWrong IQ Survey · 2012-12-02T22:32:32.243Z · LW · GW

I couldn't find any relevant discussion on the topic. Can anyone give me a link?

I'm looking for one where people have posted their scores on a reliable IQ test, rather than answering to the question "what is your IQ?".

Comment by Blackened on LessWrong IQ Survey · 2012-12-02T22:30:02.057Z · LW · GW

CFNSE score [pollid:259] Here is the percentile convertor for CFNSE. http://www.etienne.se/cfnse/norm.htm

Note that the best strategy is to look at Adults percentile, even if this is less accurate than the age group. We are looking at the intelligence compared to all humans, not compared to all humans at the same age range.

Comment by Blackened on LessWrong IQ Survey · 2012-12-02T22:28:24.352Z · LW · GW

Thanks.

Comment by Blackened on LessWrong IQ Survey · 2012-12-02T22:25:53.966Z · LW · GW

JCTI score [pollid:257] Please don't use this field for scores from other tests, except for clinical ones - note that there are some that are not free and are still not valid (one costed a few hundred Euros!). You can post scores from other tests if you are really sure they are valid, but don't forget to convert it to SD15. As far as I know, some Mensa admission tests are not accurate.

Comment by Blackened on Meetup : 02/12 London Meetup · 2012-12-02T21:55:34.279Z · LW · GW

I really wanted to come, but coursework deadlines are very close, so I had to skip this one. How did it go? How many people came?

Comment by Blackened on 2012 Less Wrong Census/Survey · 2012-11-26T22:46:06.861Z · LW · GW

Took the survey + all the extra questions. I just noticed this thread today. In my opinion, it is underadvertised.

Concerning the IQ test, I've seen this one before and I know it's not reliable, because it is not based on a statistic and there's no reason to believe it's reliable in the first place. There are only two culture-fair free online IQ tests: JCTI and CFNSE. I am extremely curious to see the average score for LW.

Here's how to make sense out of your IQ score: http://www.iqcomparisonsite.com/iqtable.aspx

Comment by Blackened on Open Thread, November 16–30, 2012 · 2012-11-23T18:11:58.921Z · LW · GW

How do I improve my persuasion skills?

How do I translate a valid logical argument to a persuasive, intuitive argument that would work for most people? I have read a lot of psychological literature. I have also gotten to the point where I can recognize an intuitive argument that would be persuasive. So, I can recognise my arguments as non-persuasive before I say them and I avoid most debates with people who aren't convinced by scientific evidence and stuff that works for rationalists and is technically a good argument. However, generating a persuasive argument isn't the same as evaluating the persuasiveness of already existing arguments.

Any good, readable, concise literature on this?

Comment by Blackened on Open Thread, November 1-15, 2012 · 2012-11-08T16:19:36.966Z · LW · GW

Any tips for productivity (links to good articles are highly appreciated)? I was thinking that I knew all the main simple rules, until a few months ago I discovered nootropics.

Comment by Blackened on Does My Vote Matter? · 2012-11-08T13:58:51.215Z · LW · GW

I have thought about this, to destroy my past erroneous belief that a single vote doesn't make a difference. Imagine that you know a secret that few people know, which tells you that the right candidate to vote is definitely candidate X. All the people who know the secret also might think in the same way as you - that a single vote doesn't matter. But the difference between all of those people voting and no one of them voting is winning the election. So there's the two situations:

  1. Nobody votes, you lose the election.
  2. Everyone votes, you win the election.

The benefit of your desired party winning the election is greater than the cost to go and vote. But if your vote adds only 0.01% chance of winning, which is not enough to outweigh the time spent for voting, why is it better for everyone who knows the secret if all of them voted?

The answer is that by voting, you don't only increase that chance by 0.01% for you, you also increase it for everyone else. So if there was two of you, you can both vote and each of you will gain a double increase for the same cost. But if you're altruistic, then the most logical thing would be to vote.

Sorry if my idea is repeated in the article or in some of the comments, I didn't read everything.

Comment by Blackened on [Link] "Fewer than X% of Americans know Y" · 2012-10-12T09:39:24.316Z · LW · GW

I remember when a few years ago, on the news on TV, there was an article about how 40-70% (forgot the exact number) of the interviewed people said that Beethoven is a dog. I was frustrated at how shocked the other people in the room were.

Comment by Blackened on Open Thread, October 1-15, 2012 · 2012-10-04T15:37:30.649Z · LW · GW

I'm talking about personal statement. Not sure if this is the same as cover letter, but I do know that they require it. And it appears that mine is going to significantly increase the overall quality of the CV.

Comment by Blackened on Open Thread, October 1-15, 2012 · 2012-10-03T10:11:28.015Z · LW · GW

Why do you think so? I would personally like more people who are actively talking about their good and bad sides, although I'm not sure if I'd do that in an interview, because it might mean they don't know what appears to be the most effective strategy.

Comment by Blackened on Open Thread, October 1-15, 2012 · 2012-10-02T21:20:58.167Z · LW · GW

I'm writing my CV now and was wondering whether I should indeed be "as confident as possible" (which basically means, according to some people, that I'm limited to sentences that don't even contain words like "but", "mostly", "although" etc.). Overconfidence is a killer of rationality, and displaying it might signal that you're irrational. I would personally trust much more someone who actively doubts in many things he says, rather than someone who is always confident. However, some people say the opposite.

I was wondering how should I approach my CV? Would it attract more rational employers if it's more self-skeptical? I'm not going to take it to a degree where it's as self-skeptical as I usually get when I give my honest advice on something (pointing out as many assumptions and dependencies on sources of information as possible, and sounding like nobody else I know, based on a very quick search). But still wondering whether this would get me a more irrational employer, and would some of you actually trust more someone who sounds confident.

Comment by Blackened on Open Thread, October 1-15, 2012 · 2012-10-02T18:11:26.151Z · LW · GW

That's because I wanted to see what their programmers study and computer science was the closest I found. I assume that their programmers would study that? And that it's better than study software engineering in a significantly worse university?

Comment by Blackened on Open Thread, October 1-15, 2012 · 2012-10-01T12:13:02.033Z · LW · GW

Any good books on mathematics for software engineers? I've been looking at the best universities in UK, they all have much more mathematics in their degree than what I'm taught.

Also, any good books for probability theory and all the things needed for AI development? I'm doing this course: https://www.edx.org/courses/BerkeleyX/CS188.1x/2012_Fall/about

Edit: These are the programs I've been talking about.

Imperial college: http://www3.imperial.ac.uk/ugprospectus/facultiesanddepartments/computing/computingcourses http://www3.imperial.ac.uk/computing/teaching/ug/mengcompse

Cambridge: http://www.study.cam.ac.uk/undergraduate/courses/compsci/

Oxford: http://www.ox.ac.uk/admissions/undergraduate_courses/courses/computer_science/computer_science_.html

I assume they teach mathematics, because it's useful for software engineers.

Comment by Blackened on Open Thread, September 1-15, 2012 · 2012-09-19T20:42:56.675Z · LW · GW

I didn't say that sexuality is entirely shaped by this, only that it's influenced. Say, when I read that hourglass-shaped women bodies are supposed to be attractive, I started noticing that I think I'm attracted to that, although one can argue that I used to be before I read it, so I only started noticing that. However, it worked for me for other things, many of which are not liked by many people.

Comment by Blackened on Open Thread, September 1-15, 2012 · 2012-09-18T20:24:25.796Z · LW · GW

Sexuality is a strange thing. If you consciously think something is sexy, it then becomes sexy for you. At least that's how it works for me, I'm generalizing from one example here.

Comment by Blackened on Open Thread, September 1-15, 2012 · 2012-09-11T18:47:38.447Z · LW · GW

That would only makes sense if vitamin D is the only one that has any real significant effects or if the other ones who do, are too included in small dosages (this doesn't seem improbable at all).

I remember seeing studies which doubt that vitamin C would help healing from common cold. No wonder if most other are as insignificant.

Also, just checked some pills of vitamins (for hair, skin and nails) I bought 1-2 years ago. It says "take 3 times a day" and it has 100 IU of vitamin D. It's also apparently 50% of RDA - most other vitamins/minerals in it are up to 200-250%, and my vitamin D pills are 1250% RDA. Mystery solved, I guess.

Comment by Blackened on Open Thread, September 1-15, 2012 · 2012-09-09T11:43:23.731Z · LW · GW

Well, so it was a good decision to play lottery after all!

(I'm joking)

But anyway, congratulations for the success and thanks for the contributions! I personally am going to donate huge amounts of money on similar causes if I get rich. It seems to be the most rational way (according to my goals) to spend them.

Comment by Blackened on Open Thread, September 1-15, 2012 · 2012-09-09T11:30:50.270Z · LW · GW

I am very confused right now.

A few years ago, I learned that multivitamins are ineffective, according to research. At that point, I have heard of the benefits of many of them, they were individually praised like some would praise anything that's good enough to take by itself, so I was thinking that multivitamins should be something ultra-effective that only irrational people won't take. When I learned they were ineffective, I hypothesized that vitamins in pills simply don't get processed well.

Recently, I was reading a few articles about Vitamin D - I thought I should definitely have it, because the sources were rather scientific and were praising it a lot. I got it in the form of softgels, because gwern suggested it. When they arrived, I saw it's very similar to pills, so I thought it might be ineffective and decided to take another look at Wikipedia/Multivitamins. Then I got very confused.

Apparently, the multivitamins DO get processed! And yes, they ARE found to have no significant effect (even in double-blind placebo trials), But at the same time, we have pages saying that 50-60% of the people are deprived from Vitamin D and that it seriously reduces the risk of cancer, among with other things (including a heart disease). Can anyone explain what's going on?

Comment by Blackened on Open Thread, September 1-15, 2012 · 2012-09-07T11:39:51.835Z · LW · GW

it says that accupuncture (both "real" and "sham") was seen to be effective in combatting pain

Oh damn I missed that. I got too distracted by the Effectiveness research section. So there you go, I found a reasonable explanation, although I was more looking forward to some sort of fundamental bias that effects everyone, which I must have somehow missed. Would have been a good explanation to some things.

Still, I'm waiting for someone to appear with a very good hypothesis of the cancer case. I'm not saying there has to necessarily be one, but there might be. Placebo was in fact a very good hypothesis, but I'm not sure if you can cure cancer with placebo ("Yes, you can" would close the case).

Edit: I looked it up, apparently placebo doesn't affect cancer. Surprising.

Comment by Blackened on Open Thread, September 1-15, 2012 · 2012-09-07T10:27:00.736Z · LW · GW

I need help in explaining this case to myself.

I just talked to someone and she praised her doctor, because she complained from chest (armpit) pain, and the doctor, untraditinally, cured her with accupuncture on the spot. I asked her and she said the pain was going on for a few weeks (and was quite intense), and it disappeared on the next day. Some bias IS expected of her (more so than from the average person).

Maybe it's just random chance plus unconscious exaggeration, but I doubt it could have been so strong. After I started writing this, I looked up on Wikipedia to confirm that there are no working forms of accupuncture, and this gave me the idea that it might have been placebo. Any other explanations I couldn't think of? I find some similar cases to be quite surrealistic, given the premise that the treatments used were proven to be ineffective. My own grandmother was supposedly sick of cancer and the doctors told her she had no more tnah a month of life, then some alternative medicine practicioner told her to drink turtle blood and she did so and she's alive now, more than 10 years later. It's extremely unlikely that my father lied about this, but I thought it was incompetent doctors - incompetency amongst physicians is quite common, according to my personal anecdotes and the theory I use to support it.

Comment by Blackened on Open Thread, July 1-15, 2012 · 2012-08-12T16:22:46.759Z · LW · GW

Ha, I got the idea for nootropics from your dual n-back article in the first place.

I'll certainly try some nicotine gums, but would that be strong? I'd like something strong, like Adderall, but I know that Adderall is illegal without prescription (damn stupid laws), and I will likely never be in the state of having an ADHD diagnosis.

Comment by Blackened on Open Thread, July 1-15, 2012 · 2012-08-11T22:25:46.014Z · LW · GW

Can anyone recommend me any nootropics for raising concentration (executive functions, working memory) that are effective, legal in the UK, not too expensive, and without too much side effects? My concentration is quite bad, if that's relevant.

Comment by Blackened on Open Thread, August 1-15, 2012 · 2012-08-08T22:59:11.840Z · LW · GW

In case (b), 1307 is as close to 1337 as are the example numbers 4337, 1037, and 1334 (among others). The found number could be closer to 1337 if it were instead 1347 or 1327 (among others).

This is the case I meant to (at least one that would be very close to what someone would use in real life). The point is to choose your own criteria for the example situation to determine whether that person is a real magician.

This can't be. If nothing else, the one group uses their left hand and the other uses their right. You need an "except" or "other than" clause.

I know, but in real life, left-handers can be a subject of stereotyping and discrimination. So I wanted to omit factors like those, like everyone does in such questions. I could have said that some have gene A and others have gene B and only you can identify people and nobody else cares about it, because it has no effect on anything, but handedness seemed more intuitive to me, for this already quite abstract question.

Did it just happen to turn out that we found ten, so we can proceed, and if we didn't find ten we'd skip this problem - or does this problem solely use classes that have ten and throw out other classes?

The problem only uses classes that have ten or more right-handers. I have edited this in the description.

In the entire class? Because that's not clear.

I have clarified that. I don't know why did I include this item, because it sort of duplicates a).

Went around shaking hands until locating a left-handed person, or grabbed the first person you saw and they were left-handed?

I have edited it to "randomly picked a left-handed person, out of all the left-handers who were there".

What, really? These are both heavily correlated with a third thing but not at all with each other? Are there real phenomena that act like that? It is unlikely to have good grades and a low score on either one, but they're not correlated?

Why not? The original was with IQ and concentration, but someone took it literally, so I decided to rename it. As far as I know, they + conscientiousness are all correlated with academic success, but not correlated with each other. Also, intelligence and social abilities are both correlated with social success.

I'm just nitpicking here, but this made me wonder if a won $35 would be taxed where the $10 wouldn't.

What do you mean? There are no taxes in either case.

This is bad wording if this is supposed to be an expected value question. The most money possible is just $35; you don't even have to work out the expected value. If you take the ten dollars you are not getting as much as you could possibly have gotten.

I think it's fine this way and I can't think of another way to word it. English isn't my first language.

Comment by Blackened on Open Thread, August 1-15, 2012 · 2012-08-08T20:32:16.273Z · LW · GW

Why the answer is different: Because 1.C asks what are expectations are, and 1.B asks what the state of the class is

For b) and c), the questions were supposed to be the same - my bad, I have edited it. Please edit your answer accordingly.

Not all of your answers were correct (unsurprisingly, because I find some of the questions extremely hard - even I couldn't answer them at first :D). I'll wait for a few more replies and then I'll post the correct answers plus explanations.

Comment by Blackened on Open Thread, August 1-15, 2012 · 2012-08-08T20:20:14.006Z · LW · GW

I meant to say, a close match to what the person said. And I'm not entirely confident that 2 makes sense, I'd like to clarify something but that would give out the answer. Please tell me of the other questions you don't understand.

Comment by Blackened on Open Thread, August 1-15, 2012 · 2012-08-08T18:32:14.918Z · LW · GW

9 months ago, I designed something like a rationality test (as in biological rationality, although parts of it depend on prior knowledge of concepts like expected value). I'll copy it here, I'm curious whether all my questions will get answered correctly. Some of the questions might be logically invalid, please tell me if they are and explain your arguments (I didn't intend any question to be logically invalid). Also, certain bits might be vague - if you don't understand it, it's likely that it's my fault. Feel free to skip any amount of questions and selectively answer only the ones you like the most. Needless to say, I'm not a psychometrician and I can't guarantee the correlation between someone's rationality and his answers to this test.

1: Assume that exactly 10% of the people in the world are left-handed. Also assume that there are absolutely no differences between left-handed and right-handed people (so that the only groups of people where the expected percentage of left-handers is different from 10% are ones where membership explicitly depends on handedness). For these examples, we are looking at a randomly picked class of 24 students from a randomly chosen school. Note: all the examples are independent and in no particular order.

a) If we randomly pick three students - turns out that all of them are left-handed - do we still expect the average number of left-handers among the remaining 21 students to be 10%?

b) We count 10 right-handers (assuming that we managed to find at least 10 right-handers - if we didn't, we would have changed the group). Among the remaining 14 students, is the average number of left-handers still 10%?

c) We randomly count 10 students. Turns out that all of them are right-handed. Is the average number of left-handers for the rest of the class still 10%? If your answer to this question was different from your answer to b), please explain why was this the case.

d) You happen to know one of the students in this class. You met him one day from a meeting, which was attended by all of the students from three of the classes in the school (out of 13 classes, each class has 24 students) - on that meeting, you randomly picked a left-handed person, out of all the left-handers who were there. Does this fact mean that the average number of left-handers in the remaining 23 students is different from 10%?

e) Out of all the left-handers in the world (about 700 million), you pick one at random. He happens to be from that class. Does this affect the average number of left-handers out of the remaining 23 people? (note that even very low changes in probability count as changes)

2: You are in Bulgaria. The number plates there always have four random numbers from 0 to 9. A person next to you claims to have psychic abilities and he says that the next car that you'll come across will have the number 1337. The next car you come across has the number 1307. You are amazed by this and think that he might have real powers. He was very close to the actual number - what is the probability for someone to guess a number as close as he did, if we assume that he only made a guess?

3: Assume that A and B are psychological factors, both significantly correlated with school grades. It's still possible (but unlikely) to have a good grades with a low score on either of them, or even both of them. Also we assume that A and B are totally uncorrelated, and that the only criteria for acceptance in a university is grades. a) If you are in a university of average quality (with correspondingly average requirements for grades), and you aim to find people who score as high on A as possible, is it a good strategy to place higher priority on people who score as high on B as possible, or should they score as low as possible? Why? b) Does your answer to a) change if the university is of low quality? What if it's of high quality? If yes, why?

4: You have to pick between a certain profit of 10$ or 35% chance of winning 30$. Assume you already are financially stable and have a lot of money. Which is the correct choice, if you want to have as much money as possible?? Why?

Comment by Blackened on Open Thread, August 1-15, 2012 · 2012-08-08T15:44:44.363Z · LW · GW

I've heard that it's often a fraud and that it usually comes at the cost of reduced reading comprehension. But I have no actual experience with it.

Comment by Blackened on Challenge: change someone's mind · 2012-07-19T20:48:50.240Z · LW · GW

Don't sweat about karma, it's there mostly for feedback and filtering, not as a judgment tool.

I didn't get this. Isn't it that people should vote down everything they disagree with?

If you define "rational" as "those who understand what I mean, rather than what I say, and agree with me", then no, you have not.

Maybe you're right, I can't possibly judge how did it look like when read from a different person. Mental contamination.

Famous last words...

Would you still say that if I said "it's 15:00 here, therefore it's not night - this contradicts your claim that it's night here, I can't possibly be biased here"? Because I said something of similar probability, and by "can't possibly", I obviously didn't mean "100% confidence", because that would be an oxymoron (I can't have 100% confidence). I expected you to point at some of my statements and claim them to be wrong, that would help me to reach your conclusion, if it's any different from mine.

Comment by Blackened on Challenge: change someone's mind · 2012-07-19T19:13:06.610Z · LW · GW

Unfortunately, it's not as simple as that. My sister (yes, I was talking about her all this time) is so prejudiced against me, she even thinks I'm physically weak (despite that I'm not just average, I'm well above the average and I even receive compliments for that; also, my lifts are significantly above the average, according to some papers I saw).

I've contradicted her so many times, she didn't bother to change her opinion. Not only that, but I've met a few of her friends who reacted like "wow, you're either an entirely different person, or your sister outright lied me about you", but I haven't done it recently and they might have not expressed this opinion loud enough.

Comment by Blackened on Challenge: change someone's mind · 2012-07-19T18:39:29.338Z · LW · GW

I can't understand how this is a popular post, giving the number of assumptions you made.

First, I don't have a brother. In my analogue of the situation, I'm kind to that person and he isn't kind to me. I never did anything bad to him (and I don't do bad things to people, by the way). But this is irrelevant, because the point here is to change the mind of someone you know who didn't change his opinion when the subject of that opinion has changed a lot.

Re your friend: "Change him to be like you" seems like a bad idea in general

By "like you", I meant in respect of skepticism. Isn't that the whole point of the community, to make other people more rational? Isn't that the whole point of popularizing skepticism? Of course I didn't mean to make him a person more like me, I thought this is so obvious that it's implicit.

"One of your friends is very deeply religious" is not necessarily a bad thing if this friend is also happy being religious.

The same person is the best (out of the people I've seen) programmer in the whole 1st year in my uni. He has a huge potential and he's wasting it. He prays 5 times per day, each taking about 30 minutes. And he does all this, because he is rigorously following what seems to be the best idea, according to his information - to be religious. Indeed, he is one of the most rational people I know. Isn't that a good thing?

"You have a friendly new acquaintance of about average intelligence" -- that sounds pretty condescending. Are you sure that you are smarter?

Okay, I used that to illustrate a person who is pretty much an average person, because personality matters a lot here. You're right that it sounds doesn't sound like what I meant and I have edited it. When I was writing it, I was very sleep deprived and I probably have other ambiguities.

Is that what I got the negative karma for? When I saw it at first, I thought I have said something wrong. But the karma on your post suggests that many people were thinking the same as you. Is it that the majority of LessWrong thinks that it's bad to change someone's mind even when it's only for his own good?

It seems that my opinion of LessWrong was very optimistic. It saddens me to think that probably I have not found the community of people who are actually rational, unlike the rest of the world. I can't possibly be biased here, because half of my counterarguments don't include significant judgments, but plain facts (2 and 3 include judgments, but the judgment part is so insignificant that I'm only saying this out of perfectionism). Any counter-counterarguments are welcome, I would be happy to see myself proven wrong here.

Edit: I have edited my original post. It did indeed sound like I'm a dark lord on the mission to bind people to his will and be like you, their opinions doesn't matter, etc.. Instead of a rationalist striving for a better world with less delusion and wasted resources.

Also, I forgot to say again how much I dislike it when people make assumptions about what I said. I didn't write "your brother" because I have a brother, but because I wanted to more accurately describe the template (but this doesn't mean that real life situations should be more similar to that example situation, I have only wanted the template to be closer to what I originally thought).

Comment by Blackened on Lotteries: A Waste of Hope · 2012-07-12T20:22:45.879Z · LW · GW

However, we assume that the social interaction itself isn't enough to justify my ticket. Let's say it's just a warm greeting and a short small talk with someone I find sympathetic, but probably won't play a decisive role in my future. And I'm buying the ticket, because I rationally know that I might win the lottery (despite that I find it so unlikely that I don't actually expect it). I have only included the social interaction to offset the wasted time.

Comment by Blackened on Lotteries: A Waste of Hope · 2012-07-12T20:12:07.203Z · LW · GW

I'm still not convinced that I shouldn't buy lottery tickets.

Assume a hypothetical situation. There's a lottery right next to where I study/work. Also, I realize how silly it is to actually expect to win the lottery after buying a lottery ticket, so I can't use this as a source of positive emotions, even if I want to. However, buying lottery tickets let me engage in certain social situations, which just barely outweigh the time wasted for them (but not the money) - alternatively, you can instead assume that it takes me 0 seconds to buy a ticket and later to check if I won.

I reckon this question has already been answered, therefore links are a completely acceptable response.

Also, I'd never buy a lottery ticket. It's because of expected value. However, I'm still trying to solidly prove that decision-wise, expected value is equivalent to predicted reality (of course, after uncertainty is taken into account).

Comment by Blackened on Learn Power Searching with Google · 2012-07-10T08:03:52.662Z · LW · GW

Registered a few days ago, now trying to run the course, but for some reason it's not working.

Edit: working now.