trentmkelly/LessWrong-43k huggingface dataset:
Dealing with the high quantity of scientific error in medicine
by NancyLebovitz — 2010-10-25T13:53:47.015Z

In a recent article, John Ioannidis describes a very high proportion of medical research as wrong.

Still, Ioannidis anticipated that the community might shrug off his findings: sure, a lot of dubious research makes it into journals, but we researchers and physicians know to ignore it and focus on the good stuff, so what’s the big deal? The other paper headed off that claim. He zoomed in on 49 of the most highly regarded research findings in medicine over the previous 13 years, as judged by the science community’s two standard measures: the papers had appeared in the journals most widely cited in research articles, and the 49 articles themselves were the most widely cited articles in these journals. These were articles that helped lead to the widespread popularity of treatments such as the use of hormone-replacement therapy for menopausal women, vitamin E to reduce the risk of heart disease, coronary stents to ward off heart attacks, and daily low-dose aspirin to control blood pressure and prevent heart attacks and strokes. Ioannidis was putting his contentions to the test not against run-of-the-mill research, or even merely well-accepted research, but against the absolute tip of the research pyramid. Of the 49 articles, 45 claimed to have uncovered effective interventions. Thirty-four of these claims had been retested, and 14 of these, or 41 percent, had been convincingly shown to be wrong or significantly exaggerated. If between a third and a half of the most acclaimed research in medicine was proving untrustworthy, the scope and impact of the problem were undeniable. That article was published in the Journal of the American Medical Association.

Part of the problem is that surprising results get more interest, and surprising results are more likely to be wrong. (I'm not dead certain of this-- if the baseline beliefs are highly likely to be wrong, surprising beliefs become somewhat less likely to be wrong.) Replication is boring. Failure to replicate a bright shiny surprising belief is boring. A tremendous amount isn't checked, and that's before you start considering that a lot of medical research is funded by companies that want to sell something.

Ioannidis' corollaries:

Corollary 1: The smaller the studies conducted in a scientific field, the less likely the research findings are to be true.

Corollary 2: The smaller the effect sizes in a scienti

...
Let's split the cake, lengthwise, upwise and slantwise
by Stuart_Armstrong — 2010-10-25T13:15:02.855Z

This post looks at some of the current models for how two agents can split the gain in non-zero sum interactions. For instance, if you and a buddy have to split £10 between the two of you, where the money is discarded if you can't reach a deal. Or there is an opportunity to trade your Elvis memorabilia for someone's collection of North Korean propaganda posters: unless you can agree to a way of splitting the gain from trade, the trade won't happen. Or there is the stereotypical battle of the sexes: either a romantic dinner (RD) or a night of Battlestar Galactica (BG) is on offer, and both members of the couple prefer doing something together to doing it separately - but, of course, each one has their preference on which activity to do together.

Unlike standard games such as Prisoner's Dilemma, this is a coordinated game: the two agents will negotiate a joint solution, which is presumed to be binding. This allows for such solutions as 50% (BG,BG) + 50% (RD,RD), which cannot happen with each agent choosing their moves independently. The two agents will be assumed to be expected utility maximisers. What would your feelings be on a good bargaining outcome in this situation?

Enough about your feelings; let's see what the experts are saying. In general, if A and C are outcomes with utilities (a,b) and (c,d), then another possible outcome is pA + (1-p)C (where you decide first, with odds p:1-p, whether to do outcome A or C), with utility p(a,b) + (1-p)(c,d). Hence if you plot every possible expected utilities in the plane for a given game, you get a convex set.

For instance, if there is an interaction with possible pure outcomes (-1,2), (2,10), (4,9), (5,7), (6,3), then the set of actual possible utilities is the pentagon presented here:

The points highlighted in red are the Pareto-optimal points: those where there is no possibility of making both players better off. Generally only Pareto-optimal points are considered valid negotiation solutions: any other point leaves both player strictly poorer than they could be.

The first and instinctive way to choose an outcome is to select the egalitarian point. This is the Pareto-optimal point where both players get the same utility (in this instance, both get 27/5 utility):

However, you can add an arbitrary number to your utility function without changing any of your decisions; your utility function is translation invaria...
Willpower: not a limited resource?
by Jess_Riedel — 2010-10-25T12:06:29.139Z

Stanford Report has a university public press release about a recent paper [subscription required] in Psychological Science. The paper is available for free from a website of one of the authors.

The gist is that they find evidence against the (currently fashionable) hypothesis that willpower is an expendable resource. Here is the leader:

Veronika Job, Carol S. Dweck, and Gregory M. Walton
Stanford University

Abstract:

Much recent research suggests that willpower—the capacity to exert self-control—is a limited resource that is depleted after exertion. We propose that whether depletion takes place or not depends on a person’s belief about whether willpower is a limited resource. Study 1 found that individual differences in lay theories about willpower moderate ego-depletion effects: People who viewed the capacity for self-control as not limited did not show diminished self-control after a depleting experience. Study 2 replicated the effect, manipulating lay theories about willpower. Study 3 addressed questions about the mechanism underlying the effect. Study 4, a longitudinal field study, found that theories about willpower predict change in eating behavior, procrastination, and self-regulated goal striving in depleting circumstances. Taken together, the findings suggest that reduced self-control after a depleting task or during demanding periods may reflect people’s beliefs about the availability of willpower rather than true resource depletion.

(HT: Brashman, as posted on HackerNews.)
A Paradox in Timeless Decision Theory
by AlexMennen — 2010-10-25T03:09:06.462Z

I'm putting this in the discussion section because I'm not sure whether something like this has already been thought of, and I don't want to repeat things in a top-level post.

Anyway, consider a Prisoner's-Dilemma-like situation with the following payoff matrix:
You defect, opponent defects: 0 utils
You defect, opponent cooperates: 3 utils
You cooperate, opponent defects: 1 util
You cooperate, opponent cooperates: 2 utils
Assume all players have either have full information about their opponents, or are allowed to communicate and will be able to deduce each others' strategy correctly.

Suppose you are a a timeless decision theory agent playing this modified Prisoner's Dilemma with an actor that will always pick "defect" no matter what your strategy is. Clearly, your best move is to cooperate, gaining you 1 util instead of no utility, and giving your opponent his maximum 3 utils instead of the no utility he would get if you defected. Now suppose you are playing against another timeless decision theory agent. Clearly, the best strategy is to be that actor which defects no matter what. If both agents do this, the worst possible result for both of them occurs.

This situation can actually happen in the real world. Suppose there are two rival countries, and one demands some tribute or concession from the other, and threatens war if the other country does not agree, even though such a war would be very costly for both countries. The rulers of the threatened country can either pay the less expensive tribute or accept a more expensive war so that the first country will back off, but the rulers of the first country have thought of that and have committed to not back down anyway. If the tribute is worth 1 util to each side, and a war costs 2 utils to each side, this is identical to the payoff matrix I described. I'd be pretty surprised if nothing like this has ever happened.
Optimism versus cryonics
by lsparrish — 2010-10-25T02:13:34.654Z

Within the immortalist community, cryonics is the most pessimistic possible position. Consider the following superoptimistic alternative scenarios:

Uploading will be possible before I die.

Aging will be cured before I die.

They will be able to reanimate a whole mouse before I die, then I'll sign up.

I could get frozen in a freezer when I die, and they will eventually figure out how to reanimate me.

I could pickle my brain when I die, and they will eventually figure out how to reanimate me.

Friendly AI will cure aging and/or let me be uploaded before I die.

Cryonics -- perfusion and vitrification at LN2 temperatures under the best conditions possible -- is by far less optimistic than any of these. Of all the possible scenarios where you end up immortal, cryonics is the least optimistic. Cryonics can work even if there is no singularity or reversal tech for thousands of years into the future. It can work under the conditions of the slowest technological growth imaginable. All it assumes is that the organization (or its descendants) can survive long enough, technology doesn't go backwards (on average), and that cryopreservation of a technically sufficient nature can predate reanimation tech.

It doesn't even require the assumption that today's best possible vitrifications are good enough. See, it's entirely plausible that it's 100 years from now when they start being good enough, and 500 years later when they figure out how to reverse them. Perhaps today's population is doomed because of this. We don't know. But the fact that we don't know what exact point is good enough is sufficient to make this a worthwhile endeavor at as early of a point as possible. It doesn't require optimism -- it simply requires deliberate, rational action. The fact is that we are late for the party. In retrospect, we should have started preserving brains hundreds of years ago. Benjamin Franklin should have gone ahead and had himself immersed in alcohol.
There's a difference between having a fear and being immobilized by it. If you have a fear that cryonics won't work -- good for you! That's a perfectly rational fear. But if that fear immobilizes you and discourages you from taking action, you've lost the game. Worse than lost, you never played.

This is something of a response to Charles Platt's recent article on Cryoptimism: Part 1 Part 2
Help: Building Awesome Personal Organization Systems
by  — 2010-10-25T01:05:18.965Z

Related to: Rationality Power Tools

I'm looking to use (or make) something that helps me achieve god-like productivity. In particular, I'm interested in any information about systems that are:

Flexible: They can be extended or customized to accommodate new work-flows and a diverse range of information structures (like to-do lists, schedules, etc.), perhaps via easy coding.

Linked: The elements can be connected and categorized using a variety of link types (like is_an_action_for, is_a_subgoal_of, etc.).

I would prefer not to have a bunch of separate systems if possible. From what I've seen so far, org-mode seems the most promising.
*Cryoburn* by Bujold
by NancyLebovitz — 2010-10-25T01:01:48.304Z

This science fiction novel is probably the best I've seen about the amount of trustworthiness needed to make large-scale cryonics work.

Minor spoilers: It's set on a planet where large corporations do the freezing and revival and can vote (in politics) as representatives of their frozen clients. Things Go Wrong, and there's even an echo of the current mortgage crisis.

On the whole, I think Bujold mistrusts any organization which is too large for individual loyalties to make a difference.

Still, it may be worth thinking about what sort of emotional/governmental/economic system it would take to make cryonics work for a large proportion of the population and/or for long periods-- and remember that for unmodified humans, mere decades are a long time.

The book is basically unsympathetic to cryonics-- sympathetic presentation of characters who choose not to be frozen, and a mention of a society which is so busy avoiding death that it's forgotten how to live. That last is just sloppy, it's not supported by the text. At least it's in favor of non-atrocious methods of rejuvenation, and she may have a point that their development will be pretty gradual. I'm not sure it's plausible that brain-transplants into clones will be developed well before any aspect of rejuvenation.

It's a fair-to-middling caper novel, or maybe somewhat better than that. It's better than the two weakest novels in the series (*Cetaganda* and *Diplomatic Immunity*) and not as good as the best (probably *Memory*, *Brothers in Arms*, and *A Civil Campaign*, though I'm also awfully fond of *Komarr* and *Mirror Dance*). I think it would make sense for the most part even if you haven't read other books in the series.
Learning the foundations of math
by jsalvatier — 2010-10-24T19:29:57.455Z

I have recently become interested in the foundations of math. I am interested in tracing the fundamentals of math in a path such as: propositional logic -> first order logic -> set theory -> measure theory. Does anyone have any resources (books, webpages, pdfs etc.) they would like to recommend?

This seems like it would be a popular activity among LWers, so I thought this would be a good place to ask for advice.

My criteria (feel free to post resources which you think others who stumble across this might be interested in):

The more basic the starting point the better: I would prefer a resource that defines propositional logic in terms of a context free grammar and an evaluation procedure (don't know if that is possible, but that's the sort of thing I am interested in) to one that just describes propositional logic in English; I would prefer a resource which builds first order logic from propositional logic + some definitions to one that just describes how first order logic works; etc.

The fewer axioms (perhaps that's not quite the right word) the better. I prefer a resource defines describes propositional logic with just two operators (say negation and conjugation) and then builds the other operators of interest to one that defines it with 5 or 6 operators (I've seen many resources which do this).

I expect that there are multiple ways to build math from basic building blocks. I am more interested in standard ways than than non-standard ways.
That which can be destroyed by the truth should *not* necessarily be
by Alex Flint — 2010-10-24T10:41:55.278Z

I've been throwing some ideas around in my head, and I want to throw some of them half-formed into the open for discussion here.

I want to draw attention to a particular class of decisions that sound much like beliefs.

Belief

Decision

There is no personal god that answers prayers.

I should badger my friend about atheism.

Cryonics is a rational course of action.

To convince others about cryonics, I should start by explaining that if we exist in the future at all, then we can expect it to be nicer than the present on account of benevolent super-intelligences.

There is an objective reality.

Postmodernists should be ridiculed and ignored.

1+1=2

If I encounter a person about to jump unless he is told "1+1=3", I should not acquiesce.

I've thrown ideas from a few different bags into the table, and I've perhaps chosen unnecessarily inflammatory examples. There are many arguments to be had about these examples, but the point I want to make is the way in which questions about the best course of action can sound very much like questions about truth. Now this is dangerous because the way in which we chose amongst decisions is radically different from the way in which we chose amongst beliefs. For a start, evaluating decisions always involves evaluating a utility function, whereas evaluating beliefs never does (unless the utility function is explicitly part of the question). By appropriate changes to one's utility function the optimal decision in any given situation can be modified arbitrarily whilst simultaneously leaving all probability assignments to all statements fixed. This should make you immediately suspicious if you ever make a decision without consulting your utility function. There is no simple mapping from beliefs to decisions.

I've noticed various friends and some people on this site making just this mistake. It's as if their love for truth and rational enquiry, which is a great thing in its own right, spills over into a conviction to act in a particular way, which itself is of questionable optimality.

In recent months there have been several posts on LessWrong about the "dark arts", which have mostly concerned using asymmetric knowledge to manipulate people. I like these posts, and I respect the moral stance implied by their name, but I fear ...
Evidential Decision Theory and Mass Mind Control
by DanielLC — 2010-10-23T23:26:42.124Z

Required Reading: Evidential Decision Theory

Let me begin with something similar to Newcomb's Paradox. You're not the guy choosing whether or not to take both boxes. You're the guy who predicts. You're not actually prescient. You can only make an educated guess.
You watch the first person play. Let's say they pick one box. You know they're not an ordinary person. They're a lot more philosophical than normal. But that doesn't mean that the knowledge of what they choose is completely useless later on. The later people might be just as weird. Or they might be normal, but they're not completely independent of this outlier. You can use his decision to help predict theirs, if only by a little. What's more, this still works if you're reading through archives and trying to "predict" the decisions people have already made in earlier trials.
The decision of the player choosing the box affects whether or not the predictor will predict that later, or earlier, people will take the box. According to EDT, one should act in the way that results in the most evidence for what one wants. Since the predictor is completely rational, this means that the player choosing the box effectively changes decisions other people make, or actually changes depending on your interpretation of EDT. One can even affect people's decisions in the past, provided that one doesn't know what they were.
In short, the decisions you make affect the decisions other people will make and have made. I'm not sure how much, but there have probably been 50 to 100 billion people. And that's not including the people who haven't been born yet. Even if you only change one in a thousand decisions, that's at least 50 million people.
Like I said: mass mind control. Use this power for good.
Tomatoes
by hangedman — 2010-10-23T18:50:14.100Z

Are tomatoes fruits or vegetables?

I've been reading Eliezer's criticisms of Aristotelian classes as a model for the meaning of words. It occurred to me that this little chestnut is a good illustration of the problem. The best part about this example is that almost everyone has argued either on one side or the other at some point in their lives. One would think that the English speaking world could come to some consensus on such a simple, trivial problem, but still the argument rages on. Fruit or vegetable?

In my experience, the argument is usually started by the fruit advocate (we'll call him Lemon). "It's the fruiting body of the plant," he says. "It contains the seeds." He argues that the tomato is, by definition, a fruit.

Bean has never thought of tomatoes as fruits, but when her belief is challenged by Lemon, she's not entirely sure how to respond. She hesitates, then starts slowly -- "All the things I call fruits are sweet," she says. "Not that tomatoes are bitter, but they're certainly not sweet enough to be fruits." Bean is proposing a stricter definition -- fruits are sweet fruiting bodies of plants. But does Bean really think that's the difference between a fruit and a vegetable?

Not really. Bean learned what these words mean by talking to other people about fruits, vegetables, and tomatoes, and through her cooking and eating. There was never any moment when she said to herself, "Aha! a tomato is not a fruit!" This belief is a result of countless minute inferences made over the course of Bean's gustatory life. The definition she proposes is an ad hoc defense of her belief that tomatoes are not fruits, not a real reason.

Bean's real mistake was to think that she needed to defend her belief that tomatoes are not fruits. Tomatoes are what they are regardless of how they're classified, and most people classify them as fruit or vegetable long before they learn anything about Aristotelian classes or membership tests. The classification is made as the result of a long history of silent inferences from the way parents and peers use those words. The first English dictionary was written in 1604, several hundred years after both "fruit" and "vegetable" had entered the English vocabulary (right about the same time as "tomato," actually). Before th...
Does anyone else find ROT13 spoilers as annoying as I do?
by nick012000 — 2010-10-23T17:15:04.957Z

Every time I come across one, it annoys me. I have to copy the text, open a new tab to the ROT13 site, paste the text, and click the translate button.

Compare this to something like a collapsable spoiler button-box where you press a button and it expands and expands a box with the appropriate text underneath it. Even making a [spoiler][/spoiler] tag that gave a black background and equally black text would be better than the current ROT13 solution.

Was there actually a reason for doing things this way? If so, why not just include the ROT13 translation in the javascript that'd open and close the textbox? Comments? Criticism?