A spell to grade tests is probably not an old spell that's been around forever since no one else seems to use it, but QQ may have invented it for this purpose.

Either way, it's existence is a further hint to the nature of magic in the world of HPMOR. It involves some pretty sophiscated natural languge processing. The fact that magic can do natural language processing is hinted as significant in chapter 6 while Harry is studying the retrieval charm and trying diffent phrases that point to "bag of gold". If we knew how magic could read a test and predict what the ministry would give it, we would know a lot more about magic.

Note, we can reject the hypothesis the the spell just doing something simple like implements a big data style algorithm with 800 years of prior tests and grades as its training corpus because QQs students are going to be writing answers that are very different from the training set and so the model wouldn't have good predictive power

Many people seem to suggest time-turner tricks for Harry to hide Hermione body. But that raises a few issues to me :

1. Do we have any evidence for or against the fact that the Hogwarts wards, or more generally a spell that Dumbledore could cast, would inform him of the usage of time-turner inside Hogwarts ? There is mention of "anti-time-loop ward", could there be "time-loop detecting wards" ?

2. Dumbledore didn't seem to check if Harry used his time-turner or not, and he didn't even ask him if he did. That's suspicious. It seems surprising that Dumbledore goes to great length to do a careful check of Harry's belonging, despite the social cost of doing so, and yet, not a single mention of the time-turner. Not even casually like the portkey. From an "outsider" point of view, it points to the fact Harry used it. Or at least, it would from many authors, but such a "oh well the NPC just didn't think about that major plot device" hand-waving doesn't seem at all to be Eliezer's way of doing things.

Brief thoughts (some redundancy with what others have said):

• This seems enormously broad. Like, this is material that could fill multiple books. I strongly suggest you narrow your focus significantly, at least at first.
• Most of these topics are very well covered elsewhere. Judging by your outline here and your linked comment, I suspect I've read many of the same things you have. That doesn't mean it's not worth covering here! But rather than duplicate effort saying things other people have already said, a well-sourced compilation of what you consider the best of the best advice might be more useful. Which leads me to...
• Make sure to include references and show your work. This is where you could really add value. Personal finance is a topic where there's a ton of folk wisdom, not all of which is going to be true, and it's not always easy to track these cached beliefs back to their source.
• If there's anywhere else where you can add specific value versus standard books and blogs on the subject, I recommend focusing there. e.g. If you can run Monte Carlo simulations, you could answer some of the questions about chances of successful retirement, the effect of charitable donations on such chances, etc.
• I'd also like to know if you have specific credentials or are a domain expert. I'm a CFA charterholder and have worked in finance for seven years (asset management in a family office), and I'm not sure I'd consider myself enough of an expert to write a sequence like this. I suspect I'd largely be passing down cached beliefs. If you have a strong reason to think otherwise for what you write, it'd be great to know.

It took me years to realize that my agreement with the Chinese Room argument was due almost entirely to how convincing Searle sounded standing in front of a classroom, and to his skill at appealing to both common sense and vanity. The argument was flagged as correct and cached, acquired a support structure of evasions and convenient flinches, and so it remained, assumed and unquestioned.

I wish I could remember an exact moment of realization that destroyed the whole thing, roots and all, but I don't. I suspect it was more of a gradual shift, where the support structure was slowly eroded by new ideas (i.e. I started reading LessWrong), and the contradictions were exposed. Until one day it came up in a discussion and I realized that, far from wanting to defend it, I didn't actually believe it anymore.

I should probably go back through my class notes (if I can find them) and see what else I might have carelessly cached.

Working on a fanfic of a fanfic of a fanart of a fanfic. At this level of recursion, the original source material has become difficult to detect. I understand at seven levels, it becomes Douglas Hofstadter slash fic. (blatant EY joke theft)

I started off writing this in second person imperative, in response to a challenge from a writer friend of mine (e.g. "You are thinking you would never write in second person imperative. Try it anyway. See what happens."). Not sure I'll stick with it, though; it works beautifully in some parts, and like chewing aluminum foil in others. Also, I'm guessing it would make it more difficult for anyone who wanted to take the recursion to another level.

It's not a huge project, probably a few thousand words going by the outline. Thought I might as well post here so as to put a little pressure on myself to actually finish it.

Used Bayes in the wild.

It was really a textbook case. I had a short story under review at Asimov's SF magazine, and they'd held onto it for over two months. Per Duotrope (a writer's market site), Asimov's takes twice as long on average reviewing stories that are ultimately accepted as stories that are ultimately rejected (the likely explanation is that obviously bad stories can be rejected right away, while stories that eventually get bought are handed around to multiple readers). So I sort of casually assumed without really thinking about it that this meant I was much more likely to get my story accepted.

But wait! Duotrope has various response statistics based on reports from users. With a few assumptions, I could use their numbers for a simple Bayes calculation, and figure out the real chances for an acceptance given a two month wait.

I used as my priors the numbers on Duotrope for acceptance rate (P(Acceptance)), mean reply time and std dev of reply time (used for P(Two Month Wait)), and took a guess at P(TMW|A) based on the mean reply time for acceptances. The result: yes, it was more likely that my piece was accepted, but because P(A) was so low to begin with (less than .5%), P(A|TMW) was still really low (less than 1%).

I calibrated my expectations accordingly. Which was just as well, since I got their rejection the next day. Rejections are always disappointing, but I'd have been far more disappointed if my expectations had still been out of joint.

YNAB (You Need A Budget)

Great tool for implementing a zero-based budgeting system (also known as an "envelope system"), meaning every dollar of income is assigned to an expense category. Categories can (and should) include annual or longer-term expenses, so that you have cash on hand when foreseeable future expenses crop up. The system as a whole is great for giving you confidence in your spending choices, as well as helping you stay on track when you overspend. I find this type of budgeting ideal, though some may find it a little too demanding.

I personally still use an older, spreadsheet-based version of the YNAB system, mainly because it's what I'm accustomed to. So I can't vouch with certainty for their current software. But it does have a free trial!

If you already have a great budgeting system in place, you may not find this useful. But if your budgeting system doesn't work so well, or if you don't currently budget--you need a budget!

Hi! Long-time lurker, first-time... joiner?

I was inspired to finally register by this post being at the top of Main. Not sure yet how much I'll actually post, but the removal of the passive barrier of, you know, not actually being registered is gone, so we'll see.

Anyway. I'm a dude, live in the Bay Area, work in finance though I secretly think I'm actually a writer. I studied cog sci in college, and that angle is what I tend to find most interesting on Less Wrong.

I originally came across LW via HPMoR back in 2010. Since then, I've read the Sequences, been to a few meetups, and attended the June minicamp (which, P.S., was awesome).

I'm still struggling a bit with actually applying rationality tools in my life, but it's great to have that toolbox ready and waiting. Sometimes... I hear it calling out to me. "Sean! This is an obvious place to apply Bayes! Seaaaaaaan!"