All of alanog's Comments + Replies

alanog
50

http://www.science20.com/hammock_physicist/rational_suckers-99998 Slightly intrigued by this article about Braess' paradox. I understand the paradox well enough, but am confused by how he uses it to critisize super-rationality. But mostly I was amused that in the same comment where he says, 'Hofstader's "super-rationality" concept is inconsistent and illogical, and no single respectable game theorist takes it seriously.' he links to EY's The True Prisoners' Dilemma post.

Also, do people know if that claim about game theorists is true? Would most game theorists say that they would defect against copies of themselves in a one-shot PD?

5Vaniver
It depends on what "against copies of themselves" means. If it means "I know the other person behaves like a game theorist, and the payoff matrix is denominated in utility," then yes. If it means "I know the other person behaves like a game theorist, but the payoff matrix is not denominated in utility because of my altruism towards a copy of myself," then no. If it means "I expect my choices to be mirrored, and the payoff matrix is denominated in utility," then no.
2betterthanwell
Neat. Upvote delivered, as promised.
alanog
00

Your example reminds me of one of Hofstadter's dialogues in The Mind's I, where he imagines that after Einstein's death, all of the information in his brain has been transcribed into a huge book of numbers which can tell you how precisely it would have responded to different inputs. It would of course be possible to 'talk' to Einstein's brain in this way, work out how his brain would change and how he would respond, and thus have a conversation with the brain. I found the question of whether such a book would be capable of consciousness (and whether it would be Einstein) baffling and a little scary, and raises many of the same problems as in your first meditation.

2[anonymous]
I'll take that as a compliment because if the "The Mind's I" is a book - I have never heard of it before - written by a famous author and you find this post similar then I suppose it can't be all bad? :) Ps. However if the book in that particular example recorded only a "still image" or a "slice" from the structure of the consciousness, then I don't think it constitutes as a recording of a thought (even though it still would be possible interact with it if it was allowed to evolve) I think that would require a recording of a three dimensional trajectory over time.
4IlyaShpitser
Importantly, such a book is "not physical" -- Einstein's computations are far too big to fit in a physical book. If you respond that this is just a thought experiment, well, the point is we have to stick to physics if we are to be reductionists. Sticking to physics actually eliminates a lot of counterintuitive thought experiments.
alanog
00

Can someone help me understand the point being made in this response? http://normaldeviate.wordpress.com/2012/11/09/anti-xkcd/

4JonathanLivengood
The point depends on differences between confidence intervals and credible intervals. Roughly, frequentist confidence intervals, but not Bayesian credible intervals, have the following coverage guarantee: if you repeat the sampling and analysis procedure over and over, in the long-run, the confidence intervals produced cover the truth some percentage of the time corresponding to the confidence level. If I set a 95% confidence level, then in the limit, 95% of the intervals I generate will cover the truth. Bayesian credible intervals, on the other hand, tell us what we believe (or should believe) the truth is given the data. A 95% credible interval contains 95% of the probability in the posterior distribution (and usually is centered around a point estimate). As Gelman points out, Bayesians can also get a kind of frequentist-style coverage by averaging over the prior. But in Wasserman's cartoon, the target is a hard-core personalist who thinks that probabilities just are degrees of belief. No averaging is done, because the credible intervals are just supposed to represent the beliefs of that particular individual. In such a case, we have no guarantee that the credible interval covers the truth even occasionally, even in the long-run. Take a look here for several good explanations of the difference between confidence intervals and credible intervals that are much more detailed than my comment here.
alanog
10

Well, there are no physics or chemistry exercies, and the linear algebra ones weren't around when I needed them. The calculus problems were useful though.

alanog
00

I don't use it systematically anymore, but it's my first port of call when I don't understand something in school or want to hear something explained differently. It works pretty well when I use it in this way, although he often goes through things more slowly than would be ideal for revision purposes.

2[anonymous]
So, you just use the videos and not the exercise?
alanog
70

Hi, I'm Alan, a student in my final year of secondary school in London, England. For some reason I'm finding it hard to remember how and when I stumbled upon Less Wrong. It was probably in March or April this year, and I think it was because Julia Galef mentioned it at some point, thought I may be misremembering.

Anyway, I've now read large chunks of the Sequences (though I can never remember which bits exactly) and HPMOR, and enjoy reading all the discussion that goes on here. I've never registered as a user before as I've never felt the burning need to c... (read more)

alanog
620

Lurker, first time poster and done!

A1987dM
110

Feel free to introduce yourself in the welcome thread.