Mathematicians & mathletes: the Singularity Institute wants your strategic input!

Once upon a time I scored a 42 on the Putnam. Two decades later I placed 23rd at the World Puzzle Championships. I'd be happy to help if I can.

But honestly? This website holds many mathematicians far better than I. Really I'm replying more from a desire to assuage my own curiosity, than from a strong belief that there exists a problem that uniquely I can solve. All I can promise you is that if I don't know the answer, I'll say so.

ETA: If anything, folks, this comment is worth downvoting for committing terrible math while bragging of being good at it. ... (read more)

A pessimistic view of quantum immortality

I generally resolve this issue with the observation that the awareness of misery takes quite a lot of coherent brainpower. By the time my perceptions are 200 years old, I suspect that they won't be running on a substrate capable of very much computational power — that is, once I pass a certain (theoretically calculable) maximum decrepitude, any remaining personal awareness is more likely to live in a Boltzmann brain than in my current body.

You see, after the vast majority of possible worlds perceive that I am dead, how likely is it that I will still have ... (read more)

09yI'm glad to see this view expressed.

Leveling IRL

(Ooh, I like that first problem. It reframes in all sorts of interesting directions.)

Example decision theory problem: "Agent simulates predictor"

Speaking only for myself: Eliezer's sequences first lured me to Less Wrong, but your posts on decision theory were what convinced me to stick around and keep checking the front page.

I confess I don't understand all of the math. It's been decades since I studied mathematics with any rigour; these days I can follow some fairly advanced theory, but have difficulty reproducing it, and cannot in general extend it. I have had nothing substantial to add, and so I haven't previously commented on one of your posts. Somehow LW didn't seem like the *best* place to go all fangirl…

It's not only the contributors who are following your work on decision theory. I hope you'll continue to share it with the rest of us.

111yI would also like to follow the discussion on decision theory.

Introduction to the Sequence Reruns

Well, perhaps this answers Yvain's question on the thread above: if we link to the original post, instead of quoting it, then its "next" buttons will work….

Introduction to the Sequence Reruns

Well, how embarrassing. Ten months of lurking and I still hadn't noticed that for myself. Thank you!

311yIt was introduced quietly and it's not very well telegraphed.

Introduction to the Sequence Reruns

My own biggest annoyance, after discovering this site last summer and delving into the Sequences, is that it was often very difficult to figure out which post came *next.*

Finding dependencies was easy — even when there isn't an explicit "Follows:" tag at the start, Eliezer's generosity of hyperlinks meant that I could quickly assemble a screenful of tabs — but whenever I finished a particularly exciting post, especially one I'd reached on the third hyperlink down, I didn't know how to find its follow-up. Early on, I didn't even know how to guess w... (read more)

There *is* a next button... but you have to click Article Navigation to find it. It'll take you to the next post in each tag.

Specific Fiction Discusion (April 2011)

Pray forgive me that I dodge this question. My brother prefers to keep his personal & professional lives separate; now that I've outed myself as his sister on a Googlable forum, I feel awkward identifying precisely *whose* sister I am.

310yTo the best of IMDB's [http://www.imdb.com/title/tt1751105/fullcredits#cast]
knowledge, there are four male voice actors (not counting John de Lancie), which
already narrows things down quite a bit.

111yAwwww. :(

Specific Fiction Discusion (April 2011)

I didn't like it at all, the first time I read it.

Many years later, after reading and enjoying *A Deepness in the Sky,* I gave it another try, and this time liked it very much. Even though the books were written in the opposite order, I wonder whether it helps to read *Deepness* first?

Specific Fiction Discusion (April 2011)

My brother is one of the actors on this show.

This brings me absolutely no inside knowledge or wisdom, but a great deal of pleasure when somebody brings it up on a rationalist message board.

211yWow, that's pretty awesome! ^_^

411yWho does he play?

New Year's Predictions Thread (2011)

Thank you; I had hit "Show more comments above" without effect, but hadn't referred back to the original post.

New Year's Predictions Thread (2011)

pb.com is a site which sells postage meters...?

011yIn context [http://lesswrong.com/lw/3kz/new_years_predictions_thread_2011/3aq2]
it means Prediction Book.

Procedural Knowledge Gaps

No, nor that they print their own names. They just have to sign their names and date the signature. It's also a good idea to have each of them initial every (numbered) page of your will; this proves that no pages have been inserted or deleted.

When I first started asking how to write a will, a couple of years ago, the best advice I got was to write the will myself — because this is free — and then reread it in a few months. Repeat this process until I couldn't think of anything to add or change. *Then* visit a lawyer and have them translate it into legalese.

Procedural Knowledge Gaps

I do not know if this is a practical, general or transferable solution, but it worked for me: throughout my childhood I couldn't orient myself, and I finally taught myself at the age of 24.

Start from a place where you can see quite some distance in all (or most) directions. Outside is best. If you can see, but are not within, a downtown core, you're in a good spot. Ditto mountains, or other tall landmarks.

Now ignore those landmarks. They're untrustworthy. If you can see them, they're close enough that sometimes they'll be north and sometimes west and... (read more)

011yI grew up just east of the Rocky Mountains, which are, being in my area more or
less straight north-south, always to the west. No fictional landmarks required.
You might be able to do something similar with a coastline, though that's quite
a bit less visible.

Techniques for probability estimates

Thanks - edited for proper italics.

Techniques for probability estimates

Inspired by your final paragraph, I sought out a variety of test questions on the web -- both on Steven's blog and elsewhere. I was expecting systematic overconfidence, with a smaller chance of systematic underconfidence, throughout the probability spectrum.

Instead I found a very interesting pattern.

When I was 90% or 95% certain of a fact, I was slightly overconfident. My 90% estimates shook out at about 80%, and my 95% estimates shook out around 90%. When I was completely uncertain of a fact, I was also slightly overconfident, but within the realm of e... (read more)

111yInteresting!
By the way, HTML tags don't work here; click "Help" to the lower right of the
edit window to see the Markup syntax rules.

How to Convince Me That 2 + 2 = 3

Well, it's so much easier and more robust that way! Instead of a long list of confoundingly similar equations, you're left with a single clear understanding of why trigonometry works. After that you can memorize a few formulas as shortcuts if it helps.

Of course this principle completely breaks down when you start working with a child who's already convinced that they can't do math—or with a group of 30 kids at once, a third of whose mathematical intuitions will be far enough from the textbook norm that no one teacher has enough time to guide them through to that first epiphany.

How to Convince Me That 2 + 2 = 3

I don't know very much about the American curriculum, having grown up with the Canadian one. But I also didn't pay very much attention in math class. I preferred to read the textbook myself, early in the year, and then play around with as many derivations and theorems as I could figure out, occasionally popping my head above water long enough for a test.

I wrote and memorized my own subtraction tables, and invented a baroque and complicated system for writing negative numbers -- for example, 1 - 2 = 9-with-a-circle-around-it, and 5 - 17 = 8-with-two-circl... (read more)

111yYour method of subtraction is similar to being the p-adic numbers, you might
want to look them up!

211yWell, it does also matter in practice that you can communicate effectively (a
lesson I had to learn myself at that age). But learning how to translate from an
idiosyncratic system into a standard one can be a source of even better
learning, so I agree that kids should not be discouraged from inventing
nonstandard but valid systems.

411yI never bothered to memorize trig equivalences. Instead, I just reduced sine,
cosine, and tangent (and their inverses) to ratios of the sides of a triangle,
and then used the Pythagorean theorem.

How to Convince Me That 2 + 2 = 3

In fact I once had this sort of mathematical experience.

Somehow, while memorizing tables of arithmetic in the first grade, I learned that 11 - 6 = 7. This equation didn't come up very often in elementary school arithmetic, and even more seldom in high school algebra, and so I seldom got any math questions marked wrong. Then one day at university, I received back a Math 300 homework assignment on which I'd casually asserted that 11 - 6 - 7. My TA had drawn a red circle around the statement, punctuating it with three question marks and the loss of a singl... (read more)

711yI don't know if the American elementary curriculum is better than it was (I hope
so) but this mistake is less likely to happen now. My niece in 2nd grade is
learning different methods of 'knowing' arithmetic. They still memorize tables,
but they also spend a lot of time practicing what they call 'strategies for
learning the addition facts [http://olc.spsd.sk.ca/de/math1-3/p-mentalmath.html]
'.
For example..
11-6 = (10-6)+1 = 5 is the compensation approach.
and 11-6 = 10-5 is the equal additions approach.
They also spend a lot of time doing mental math. I'm impressed with how
different things are, and hope that students are doing better with this more
empirical, constructivist approach. (My niece is good at math anyway, so I don't
know if she's getting more out of it than average.)

The day-to-day cognitive skills I've mastered most completely (I will not say "rationalist skills," because this is true of my countless irrational skills too) are the ones which I learned during a moment of strong emotion — any emotion, excitement or curiosity or joy or surprise or depression or fear or betrayal.

In the case of this particular skill, it was betrayal. I brought it on myself — the details aren't important; suffice it that I spent two weeks living in the "should-universe" (I like this term) before a rude reminder of reali... (read more)