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Comment author: AlexSchell 15 July 2015 08:47:39PM 5 points [-]

John Maynard Smith's Evolutionary Genetics is a classic textbook. The second edition has simulation/programming exercises after every chapter. Have fun :)

Comment author: Vaniver 22 March 2015 06:46:31PM *  3 points [-]

How did they come up with the likelihood distribution? Maybe they sampled 100 products from each machine and for each sample counted the number of faulty products. Maybe they sampled 1.000.000 products from each machine...

We don't know which sample size is used: the likelihood distribution doesn't reveal this.

Implicitly, they have an infinite sample size, because the distribution on P(B|A_1) is infinitely precise. Suppose we also wanted to learn P(B|A_1) from the history of the factory: then we might model it as having a fixed rate of defective outputs, and the probability we assign to particular defect rates is a beta distribution. We might start off with a Jeffreys prior and then update as we see the tool produce defective or normal products, eventually ending up with, say, a beta(5.5,95.5) for tool A_1.

Exercise for the reader: given that hyperparameter distribution for P(B|A_1) (and similar ones for A_2 and A_3), do we need the full hyperparameter distribution for all three tools to determine the probability that a known defective output came off of A_1, or can we get the same answer using only a handful of moments from each distribution?

Comment author: AlexSchell 22 March 2015 08:15:34PM *  1 point [-]

Hayrff guvf vf gevpxvre guna vg frrzf, whfg gur svefg zbzrag bs rnpu qvfgevohgvba fubhyq qb. (Sbe guvf ernfba V qvfnterr gung gur Jvxv negvpyr vzcyvpvgyl nffhzrf vasvavgr fnzcyr fvmr. Gur pbaqvgvbany cebonovyvgvrf hfrq va gur pnyphyngvba ner gur svefg zbzragf (= pbafgnagf) bs gur erfcrpgvir cnenzrgre qvfgevohgvbaf, abg gur cnenzrgref gurzfryirf (= enaqbz inevnoyrf).)

Comment author: MathMage 11 March 2015 04:34:01PM 1 point [-]

Huh? Harry thought it was McGonagall. What in this chapter changes that?

Comment author: AlexSchell 12 March 2015 06:35:05AM 2 points [-]

The narration in the passage is extremely suggestive that someone other than McGonagall was at work. Dumbledore and Quirrell used to be the main candidate hypotheses for who it was, until this chapter basically confirmed it was Dumbledore.

Comment author: AlexSchell 10 March 2015 08:20:02PM 6 points [-]

Aww, so Dumbledore was the one who told Harry to look for Hermione on the train in chapter 6 :)

Comment author: AlexSchell 01 February 2015 04:40:23AM 15 points [-]

Donated $100.

Comment author: [deleted] 26 January 2015 03:59:02AM *  7 points [-]

Could use an editor or feedback of some kind for a planned series of articles on scarcity, optimization, and economics. Have first four articles written and know what the last article is supposed to say, and will be filling in the gaps for a while. Would like to start posting said articles when there is enough to keep up a steady schedule.

No knowledge of economics required, but would be helpful if you were pretty experienced with how the community likes information to be presented. Reply to this comment or send me a message, and let me know how I can send you the text of the articles.

In response to comment by [deleted] on Open thread, Jan. 26 - Feb. 1, 2015
Comment author: AlexSchell 30 January 2015 07:15:06PM 3 points [-]

Contact info sent.

Comment author: zedzed 20 January 2015 02:03:42AM 1 point [-]

To tl;dr a tl;dr

  • Seeds (read: grains) have the highest concentration of "don't eat me" toxins, because of the role they play in reproduction; phytic acid, for instance, inhibits absorption of several minerals.

  • Humans can live off vegetables and some fish (Kitavans) or almost entirely meat (Inuit) and be pretty healthy. However, even animals optimized for eating seeds, much less humans, cannot live off grains exclusively without developing pellegra and beriberi.

  • Cereals have exceptionally high energy density, which may lead to overfeeding.

  • It's plausible grains interfere with satiety responses via endocrine disruption

  • Grains have a bad omega-3 : omega-6 ratio.

  • Grains have poor nutrient density.

Distilling Lindeberg's object-level advice: eat lean meat, fish, vegetables (including root vegetables), fruit, and nuts (but not too many). Do not eat grains, dairy, sugar, beans, or processed things. Drink water. I've written about how he comes to this (and my reservations about the lack of extant evidence to support any strong recommendations, including his) previously.

Comment author: AlexSchell 20 January 2015 06:34:45PM 1 point [-]

You shouldn't care much about omega-3/6 ratio in grains because they don't usually have much of either. Same for meat.

Comment author: James_Miller 13 January 2015 10:12:12PM *  2 points [-]

if lots of people start/stop eating meat, the short-run supply curve will look different 5 years from now due to that change alone.


I'm curious, given my credentials with what probability do you think I'm right?

Edit: I'm embarrassed by this, but I retract what I said.

Comment author: AlexSchell 16 January 2015 05:00:37AM 3 points [-]

I think I know the difference between changes in supply and movement along the supply curve, and your post confuses me. I take the OP's point to be that, in the long run, a change in demand shifts the short-run supply curve. This is exactly the sort of long-run dynamics scenario McAfee talks about (section 4.2.2, e.g. figures on p. 106). Is McAfee wrong or am I really missing something?

Comment author: AlexSchell 14 January 2015 02:58:39AM *  5 points [-]

If you look at net worth counterfactuals, the person deciding whether to borrow money to buy BTC is facing the same decision as someone who is already in debt and is deciding whether to buy BTC or use the same money to pay off some of their debt. If you think leveraged investments in BTC are unwise, you should also categorically advise people with any amount of debt to not buy BTC.

Comment author: Lumifer 07 January 2015 07:35:33PM 1 point [-]

I haven't looked at the empirical evidence because I didn't think it would be as convincing as the 2 theoretical arguments

Heh. It seems we have pronounced... methodological differences :-D

Comment author: AlexSchell 07 January 2015 08:01:54PM 3 points [-]

Empirically, some industries are approximately constant-cost, others are increasing- and decreasing-cost. OP mentioned certain factors pushing one way or the other, but ultimately the slope of the long-run supply curve of an industry is determined by which factors predominate, so we'd have to measure it to be sure. What is generally true, however, is that long-run supply is typically highly elastic, so cost doesn't change much from marginal changes in demand.

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