Genes take charge and diets fall by the wayside.

You need a New York Times account to read it, but setting one up only takes a couple of minutes. Here are some exerpts in any case.

Obese people almost always regain weight after weight loss:

So Dr. Hirsch and his colleagues, including Dr. Rudolph L. Leibel, who is now at Columbia University, repeated the experiment and repeated it again. Every time the result was the same. The weight, so painstakingly lost, came right back. But since this was a research study, the investigators were also measuring metabolic changes, psychiatric conditions, body temperature and pulse. And that led them to a surprising conclusion: fat people who lost large amounts of weight might look like someone who was never fat, but they were very different. In fact, by every metabolic measurement, they seemed like people who were starving.

Before the diet began, the fat subjects’ metabolism was normal — the number of calories burned per square meter of body surface was no different from that of people who had never been fat. But when they lost weight, they were burning as much as 24 percent fewer calories per square meter of their surface area than the calories consumed by those who were naturally thin.

Thin people who are forced to gain weight find it easy to lose it again:

...His subjects were prisoners at a nearby state prison who volunteered to gain weight. With great difficulty, they succeeded, increasing their weight by 20 percent to 25 percent. But it took them four to six months, eating as much as they could every day. Some consumed 10,000 calories a day, an amount so incredible that it would be hard to believe, were it not for the fact that there were attendants present at each meal who dutifully recorded everything the men ate.

Once the men were fat, their metabolisms increased by 50 percent. They needed more than 2,700 calories per square meter of their body surface to stay fat but needed just 1,800 calories per square meter to maintain their normal weight.

When the study ended, the prisoners had no trouble losing weight. Within months, they were back to normal and effortlessly stayed there.

The body's metabolism changes with weight loss and weight gain:

The implications were clear. There is a reason that fat people cannot stay thin after they diet and that thin people cannot stay fat when they force themselves to gain weight. The body’s metabolism speeds up or slows down to keep weight within a narrow range. Gain weight and the metabolism can as much as double; lose weight and it can slow to half its original speed.

Genes and weight:

.A few years later, in 1990, Dr. Stunkard published another study in The New England Journal of Medicine, using another classic method of geneticists: investigating twins. This time, he used the Swedish Twin Registry, studying its 93 pairs of identical twins who were reared apart, 154 pairs of identical twins who were reared together, 218 pairs of fraternal twins who were reared apart, and 208 pairs of fraternal twins who were reared together.

The identical twins had nearly identical body mass indexes, whether they had been reared apart or together. There was more variation in the body mass indexes of the fraternal twins, who, like any siblings, share some, but not all, genes.

The researchers concluded that 70 percent of the variation in peoples’ weights may be accounted for by inheritance, a figure that means that weight is more strongly inherited than nearly any other condition, including mental illness, breast cancer or heart disease.

There's been more recent work suggesting that planets are extremely common. Most recently, evidence for planets in unexpected orbits around red dwarfs have been found. See e.g. here. This is in addition to other work suggesting that even when restricted to sun-like stars, planets are not just common, but planets are frequently in the habitable zone. Source(pdf). It seems at this point that any aspect of the Great Filter that is from planet formation must be declared to be completely negligible. Is this analysis accurate?

To whoever fixed it so that we can see the parents of comments when looking at a user's comments, major props to you for being awesome.

I just found out that there exists an earlier term for semantic stopsigns: a thought-terminating cliché.

A thought-terminating cliché is a commonly used phrase, sometimes passing as folk wisdom, used to quell cognitive dissonance. Though the phrase in and of itself may be valid in certain contexts, its application as a means of dismissing dissent or justifying fallacious logic is what makes it thought-terminating.

The term was popularized by Robert Jay Lifton in his 1956 book Thought Reform and the Psychology of Totalism. Lifton said, “The language of the totalist environment is characterized by the thought-terminating cliché. The most far-reaching and complex of human problems are compressed into brief, highly reductive, definitive-sounding phrases, easily memorized and easily expressed. These become the start and finish of any ideological analysis.”

I was an intern at MIRI recently and I would like to start a new LW meetup in my city but as I am still new on LW, I do not have enough karma points. Could you please upvote this comment so that I can get enough karma to post about a meetup? lukeprog suggested I do this. I only need 2 points to post in the discussion part. Thanks to you all

I just realized that willingness to update seems very cultish from outside. Literally.

I mean -- if someone joins a cult, what is the most obvious thing that happens to them? They update heavily; towards the group teachings. This is how you can tell that something wrong is happening.

We try to update on reasonable evidence. For example we would update on a scientific article more than on a random website. However, from outside is seems similar to willingness to update on your favorite (in-group) sources, and unwillingness to update on other (out-group) sources. Just like a Jehovah Witness would update on the Watch Tower, but would remain skeptical towards Mormon literature. As if the science itself is your cult... except that it's not really the science as we know it, because most scientist behave outside the laboratory just like everyone else; and you are trying to do something else.

Okay, I guess this is nothing new for a LW reader. I just realized now, on the emotional level, how willingness to update, considered a virtue on LW, may look horrifying to an average person. And how willingness to update on trustworthy evidence more than on untrustworthy evidence, probably seems like hypocrisy, like a rationalization for preferring your in-group ideas to out-group ideas.

Has anyone written a worthwhile utilitarian argument against transhumanism? I'm interested in criticism, but most of it is infested with metaphysical and metaethical claims I can't countenance.

Thanks for bringing back the bright-colored edges for new comments.

The additional thing I'd like to see along those lines is bright color for "continue this thread" and "expand comments" if they include new comments. I'd also like to see it for "comment score below threshold", but I can understand if that isn't included for social engineering reasons.

Risks of vegetarianism and veganism

Personal account of physical and emotional problems encountered by the author which were reversed when he went back to eating animal products. Much discussion of vitamins and dietary fats, not to mention genetic variation. Leaves the possibility open that some people thrive on a vegetarian diet, and possibly on a vegan diet.

So I'm interested in taking up meditation, but I don't know how/where to start. Is there a practical guide for beginners somewhere that you would recommend?

More grist for the hypothetical Journal of Negative Results

Scientist wants to publish replication failure. Nature won't accept the article (even as a letter). So scientist retracts previous letter written in support of the non-replicated study.

How do other people use their whiteboards?

After having my old 90 x 60 whiteboard stashed down the side of my bed since I moved in, nearly two years ago, I finally got around to mounting it a couple of weeks ago. I am amazed at how well it compliments the various productivity infrastructure I've built up in the interim, to the point where I'm considering getting a second 120 x 90 whiteboard and mounting them next to each other to form an enormous FrankenBoard.

A couple of whiteboard practices I've taken to:

• Repeated derivation of maths content I'm having trouble remembering. If there's a proof or process I'm having trouble getting to stick, I'll go through it on the board at spaced intervals. There seems to be a kinaesthetic aspect to using the whiteboard that I don't have with pen and paper, so even if my brain is struggling to to remember what comes next, my fingers will probably have a good idea.

• Unlike my other to-do list mechanisms, if I have a list item with a check box on the whiteboard, and I complete the item, I can immediately draw in a "stretch goal" check box on the same line. This turns into an enormous array of multicoloured check-boxes over time, which is both gratifying to look at and helpful when deciding what to work on next.

While researching a forthcoming MIRI blog post, I came across the University of York's Safety Critical Mailing List, which hosted an interesting discussion on the use of AI in safety-critical applications in 2000. The first post in the thread, from Ken Firth, reads:

...several of [Vega's] clients seek to use varying degrees of machine intelligence - from KBS to neural nets - and have come for advice on how to implement them in safety related systems... So far we have usually resorted to the stock answer "you don't — at least not for safety critical functions", but this becomes increasingly difficult to enforce, even if your legal and moral ground is sound. Customers are increasingly pleading the need for additional functionality and for utility to have precedence over safety (!!)

The thought of having to apply formal proofs to intelligent systems leaves me cold. How do you provide satisfactory assurance for something that has the ability to change itself during a continuous learning process? I can only assume that one would resort to black box testing, with all its inherent shortcomings and uncertainties - in particular, a black-box test would only apply to the version tested, and not to subsequent evolutions...

My fear is that the longer we ignore this problem, the more likely that users will simply ignore the safety community and press on regardless (precedents from US naval combat systems and commercial operating systems??). Can anyone offer pragmatic advice to customers who are likely to use IKBS anyway? Personally I think that I prefer... [to avoid] putting unvalidatable systems in the safety-critical firing line. But for how long can we continue to achieve this?

I encountered this thread via an also-interesting technical report, Harper (2000).

http://www.interfluidity.com/v2/4435.html

Just after the PRISM scandal broke, Tyler Cowen offered a wonderful, wonderful tweet:

I’d heard about this for years, from “nuts,” and always assumed it was true.

There is a model of social knowledge embedded in this tweet. It implies a set of things that one believes to be true, a set of things one can admit to believing without being a “nut”, and an inconsistency between the two. Why the divergence? Oughtn’t it be true that people of integrity should simply own up to what they believe? Can a “marketplace of ideas” function without that?

It’s obvious, of course, why this divergence occurs. Will Wilkinson points to an economy of esteem, but there is also an economy of influence. There are ideas and modes of thought that are taboo in the economy of influence, assertions that discredit the asserter. Those of us who seek to matter as “thinkers” are implicitly aware of these taboos, and we navigate them mostly by avoiding or acceding to them. You can transgress a little, self-consciously and playfully, as Cowen did in his tweet. If you transgress too much, too earnestly, you are written off as a nut or worse. Conversely, there are ideas that are blessed in the economy of influence. These are markers of “seriousness”, as in Paul Krugman’s perceptive, derisive epithet “Very Serious People”. This describes “thinkers” whose positions inevitably align like iron filings to the pull of social influence, indifferent to evidence that might impinge upon their views. Most of us, with varying degrees of consciousness, are pulled this way and that, forging compromises between what we might assert in some impossible reality where we observed social facts “objectively” and the positions that our allegiances, ambitions, and taboos push us towards. Individually, there is plenty of eccentricity, plenty of noise. People go “off the reservation” all the time. But pub[l]ic intellectualizing is a collective enterprise. What matters is not what some asshole says, but the conventional wisdom we coalesce to. When the noise gets averaged out, the bias imposed by the economy of influence is hard to overcome. And the economy of influence pulls, always, in directions chosen by incumbent holders of wealth and power, by people with capacity to offer rewards and to mete out punishment.

[I made a request for job finding suggestions. I didn't really want to leave details lying around indefinitely, to be honest, so, after a week, I edited it to this.]

I would like to get better at telling stories in conversations. Usually when I tell a story, it's very fact-based and I can tell that it's pretty boring, even if it wasn't for me. Are there any tips/tricks/heuristics I can implement that can transform a plain fact-based story into something more exciting?

I have started writing a Death Note fanfiction where the characters aren't all as dumb as a bag of bricks (or one could say a rationalist fic) and... I need betas. The first chapter is available on http://www.fanfiction.net/s/9380249/1/Rationalising-Death and the second is pretty much written, but the first is confirmedly "funky" in writing and since I'm not a native English speaker I'm not sure I can actually pinpoint what exactly is wrong with it. Also I'd love the extra help.

Anyone interested? My email for contact is [email protected] (and I also have a tumblr account, http://scientiststhesis.tumblr.com )

Since I'm used to hearing Dutch Book arguments as the primary way of defending expected utility maximization, I was intrigued to read this passage (from here):

The Dutch book argument concerns the long-term consistency of accepting bets. If probabilities are assigned to bets in a way that goes against the principles of CP [Classical Probability] theory, then this guarantees a net loss (or gain) across time. In other words, probabilistic assignment inconsistent with CP theory leads to unfair bets (de Finetti et al. 1993). [...]

These justifications are not without problems. Avoiding a Dutch book requires expected value maximization, rather than expected utility maximization, that is, the decision maker is constrained to use objective values rather than personal utilities, when choosing between bets. However, decision theorists generally reject the assumption of objective value maximization and instead allow for subjective utility functions (Savage 1954). This is essential, for example, in order to take into account the observed risk aversion in human decisions (Kahneman & Tversky 1979). When maximizing subjective expected utility, CP reasoning can fall prey to Dutch book problems (Wakker 2010).

The Wakker 2010 reference is to a book; searching it for "dutch book" gets me the footnote

In a later chapter on expected utility we will show that a Dutch book and arbitrage are possible as soon as there is risk aversion (Assignment 3.3.6).

And looking up assignment 3.3.6 gets

Assignment 3.3.6. This assignment demonstrates that risk aversion implies arbitrage. More generally, it shows that every deviation from risk neutrality implies arbitrage.

You may assume that risk neutrality for all 50–50 prospects implies complete risk neutrality. Show that arbitrage is possible whenever there is no risk neutrality, for instance as soon as there is strict risk aversion. A difficulty in this assignment is that we have defined risk neutrality for decision under risk, and arbitrage has been defined for decision under uncertainty. You, therefore, have to understand §2.1–2.3 to be able to do this assignment.

Since I don't really have the time or energy to work my way through a textbook, I thought that I'd ask people who understood decision theory better: exactly what is the issue, and how serious of a problem is this for somebody using the Dutch Book argument to argue for EU maximization?

All students including liberal arts students at Singapore's new Yale-NUS College will take a new course in Quantitative Reasoning which John Baez had a hand in designing.

Baez writes that it will cover topics like this:

• innumeracy, use of numbers in the media.
• visualizing quantitative data.
• cognitive biases, operationalization.
• qualitative heuristics, cognitive biases, formal logic and mathematical proof.
• formal logic, mathematical proofs.
• probability, conditional probability (Bayes’ rule), gambling and odds.
• decision trees, expected utility, optimal decisions and prospect theory.
• sampling, uncertainty.
• quantifying uncertainty, hypothesis testing, p-values and their limitations.
• statistical power and significance levels, evaluating evidence.
• correlation and causation, regression analysis.

John Baez, Quantitative Reasoning at Yale-NUS College