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Comment author: bentarm 10 May 2014 12:00:06AM 0 points [-]

The Revelation Principle feels like one of those results that flip flops between trivially obvious and absurdly impossible... I'm currently in an "absurdly powerful" frame of mind.

I guess the principle is mostly useful for impossibility results? Given an arbitrary mechanism, will you usually be able to decompose it to find the associated incentive compatible mechanism?

Comment author: napieed 02 December 2013 09:47:16PM *  7 points [-]

One shouldn't compare apples to oranges. But it's fair to say both are food.

--Scott Adams

Comment author: bentarm 06 December 2013 06:13:19PM 2 points [-]

I'm not sure I get this - If you're not allowed to compare apples to oranges, how do you decide which to eat? Is that the point this quote is trying to make?

Comment author: Alejandro1 02 December 2013 12:23:26AM 10 points [-]

A classic illustration of how to use (and how to not use) conditional probabilities:

"'Her foot,' says the journal, 'was small- so are thousands of feet. Her garter is no proof whatever- nor is her shoe- for shoes and garters are sold in packages. The same may be said of the flowers in her hat. One thing upon which M. Beauvais strongly insists is, that the clasp on the garter found had been set back to take it in. This amounts to nothing; for most women find it proper to take a pair of garters home and, fit them to the size of the limbs they are to encircle, rather than to try them in the store where they purchase.'

Here it is difficult to suppose the reasoner in earnest. Had M. Beauvais, in his search for the body of Marie, discovered a corpse corresponding in general size and appearance to the missing girl, he would have been warranted (without reference to the question of habiliment at all) in forming an opinion that his search had been successful. If, in addition to the point of general size and contour, he had found upon the arm a peculiar hairy appearance which he had observed upon the living Marie, his opinion might have been justly strengthened; and the increase of positiveness might well have been in the ratio of the peculiarity, or unusualness, of the hairy mark. If, the feet of Marie being small, those of the corpse were also small, the increase of probability that the body was that of Marie would not be an increase in a ratio merely arithmetical, but in one highly geometrical, or accumulative. Add to all this shoes such as she had been known to wear upon the day of her disappearance, and, although these shoes may be 'sold in packages,' you so far augment the probability as to verge upon the certain. What, of itself, would be no evidence of identity, becomes through its corroborative position, proof most sure. Give us, then, flowers in the hat corresponding to those worn by the missing girl, and we seek for nothing farther. If only one flower, we seek for nothing farther- what then if two or three, or more? Each successive one is multiple evidence- proof not added to proof, but multiplied by hundreds or thousands. Let us now discover, upon the deceased, garters such as the living used, and it is almost folly to proceed. But these garters are found to be tightened, by the setting back of a clasp, in just such a manner as her own had been tightened by Marie shortly previous to her leaving home. It is now madness or hypocrisy to doubt. … But it is not that the corpse was found to have the garters of the missing girl, or found to have her shoes, or her bonnet, or the flowers of her bonnet, or her feet, or a peculiar mark upon the arm, or her general size and appearance- it is that the corpse had each and all collectively.

--Edgar Allan Poe, "The Mystery of Marie Roget"

Comment author: bentarm 02 December 2013 12:34:04AM 3 points [-]

If only one flower, we seek for nothing farther- what then if two or three, or more? Each successive one is multiple evidence- proof not added to proof,

Hard to tell out of context, but is this claiming that each successive flower is independent evidence? In general, it feels like the reasoner is missing some dependency relationships between bits of evidence here.

Comment author: dv82matt 17 November 2013 05:54:50AM *  11 points [-]

But can you be 99.99% confident that 1159 is a prime?

This doesn't affect the thrust of the post but 1159 is not prime. Prime factors are 19 and 61.

Comment author: bentarm 21 November 2013 12:46:12AM 0 points [-]

I was about 80% sure that 1159 was not prime, based on reading that sentence. It took me <1 minute to confirm this. I can totally be more than 99.99% sure of the primality of any given four-digit number.

In fact, those odds suggest that I'd expect to make one mistake with probability >0.5 if I were to go through a list of all the numbers below 10,000 and classify them as prime or not prime. I think this is ridiculous. I'm quite willing to take a bet at 100 to 1 odds that I can produce an exhaustive list of all the prime numbers below 1,000,000 (which contains no composite numbers), if anyone's willing to stump up at least $10 for the other side of the bet.

In response to comment by bentarm on The best 15 words
Comment author: [deleted] 18 October 2013 12:00:11AM 0 points [-]

would your recommend this book overall?

In response to comment by [deleted] on The best 15 words
Comment author: bentarm 20 October 2013 08:37:36AM 2 points [-]

To be honest, no. There really isn't much more to it than is contained in the sixteen words above, or listening to one of Kaufman's TedX talks.

In response to The best 15 words
Comment author: bentarm 04 October 2013 12:32:09PM 16 points [-]

The First 20 Hours (Josh Kaufman):

Practice something for 20 hours, and you'll learn a lot. Don't worry about feeling stupid/clumsy.

Comment author: Swimmer963 11 September 2013 12:56:06AM 1 point [-]

it really doesn't matter what you do in high school, as long as you get into the college you're aiming to get into.

That's a bit my point, but not entirely. I think that 10 or 20 years later, the specifics of what high schoolers did will almost never matter. (General high school work ethic and direction/ambition in life likely does matter, if only because it will correlate, in most people, with adult work ethic and ambition). To a lesser degree, 10 or 20 years down the road, it probably doesn't matter whether a student got into their top choice or second-or-third choice college. College admissions depend on a lot of random factors, like whether you were sick on the day of a high school exam worth 40% of your grade, and more time passing flattens out this randomness. Students with good work ethic and a strong direction in life will probably end up where they want to be anyway, once 10-20 years have passed. Students who don't really know what they want to do still won't know in 10 years even if they went to a prestigious college. Good work ethic and ambition is correlated with getting into prestigious colleges, but I would argue that there's less causation there than this article seems to imply.

This is just my impression, though, and I'm generally not that ambitious. It might be different for people at higher level of driven-ness and/or with different, more academic-based goals.

Vaniver: I said "it surprises me how much..." because I expect to agree with most LW posts, and I'm slightly surprised every time I don't agree. It's a good surprise.

Comment author: bentarm 13 September 2013 07:21:48AM 0 points [-]

How about this as a counter-example? This guy essentially got into Harvard because of one accident with a plagiarised essay when he was a kid (at least, that's the way he tells his story), and is now a member of faculty at Chicago. I think life outcomes might be more path-dependent than we like to admit.

http://www.thisamericanlife.org/radio-archives/episode/504/how-i-got-into-college

Comment author: JonahSinick 08 September 2013 10:34:51PM *  6 points [-]

One thing that's unambiguous is that many ambitious high schoolers believe that where they go to college matters a great deal. My post is intended to address this audience.

As for how and how much undergraduate institution attended impacts life outcomes, I'll be writing about the subject at great length in the future, but in response to your reaction that it doesn't matter, for now, consider the following:

  1. According to a survey of 1.2 million graduates of US colleges, the median mid-career incomes of colleges are $137k – $120k (#1-#5), $120k — $108k (#6 – #20), and $108k – $99k (#21 – #50). There's an obvious confounding factor of ability bias, but correlation is still evidence of some degree of causation.
  2. If you're going into academia, the status of the professors who write your graduate school admissions recommendation is higher if you go to a more prestigious school.
  3. Anecdotally, finance and management consulting firms recruit disproportionately from Harvard, Yale and Princeton
  4. If Sergei Brin and Larry Page hadn't gone to Stanford CS graduate school, they may not have met and may not have started Google. Similarly, if Mark Zuckerberg hadn't gone to Harvard undergraduate, he may not have had as strong programmer friends to start Facebook with (and conversely, the early employees of Facebook wouldn't have had the opportunity to work with him).
Comment author: bentarm 09 September 2013 12:19:22PM 1 point [-]

One thing that's unambiguous is that many ambitious high schoolers believe that where they go to college matters a great deal. My post is intended to address this audience.

It's possible that I misread, but I interpreted Swimmer963's point as saying exactly this - it really doesn't matter what you do in high school, as long as you get into the college you're aiming to get into. If this is what she meant, I probably agree - I don't think there is any one-semester high school course which can't be entirely learnt by a reasonably bright student in about 1 week of dedicated personal study.

Comment author: bentarm 05 September 2013 04:40:20PM 7 points [-]

Does anyone think they could win as the AI if the logs were going to be published? (assume anonymity for the AI player, but not for the gatekeeper)

Comment author: Vaniver 02 September 2013 07:21:57PM 3 points [-]

It looks to me like you're making the sophisticated point that some facts vary in usefulness. I agree.

The point being made by Gradgrind is much more basic: children should focus on Fact over Fancy. As an example, he refuses to teach his children fairy tales, deciding that they should learn science instead. (Unfortunately, Dickens presents science as dull collections in cabinets, and so the children are rather put out by this.)

Comment author: bentarm 05 September 2013 04:22:51PM 4 points [-]

The point being made by Gradgrind is much more basic: children should focus on Fact over Fancy.

ah, ok. I interpreted it as a preference for teaching Fact rather than Theory.

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