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Feed the spinoff heuristic!

49 CarlShulman 09 February 2012 07:41AM

Follow-up to:

Parapsychology: the control group for science

Some Heuristics for Evaluating the Soundness of the Academic Mainstream in Unfamiliar Fields

Recent renewed discussions of the parapsychology literature and Daryl Bem's recent precognition article brought to mind the "market test" of claims of precognition. Bem tells us that random undergraduate students were able to predict with 53% accuracy where an erotic image would appear in the future. If this effect was actually real, I would rerun the experiment before corporate earnings announcements, central bank interest rate changes, etc, and change the images based on the reaction of stocks and bonds to the announcements. In other words, I could easily convert "porn precognition" into "hedge fund trillionaire precognition."

If I was initially lacking in the capital to do trades, I could publish my predictions online using public key cryptography and amass an impressive track record before recruiting investors. If anti-psi prejudice was a problem, no one need know how I was making my predictions. Similar setups could exploit other effects claimed in the parapsychology literature (e.g. the remote viewing of the Scientologist-founded Stargate Project of the U.S. federal government). Those who assign a lot of credence to psi may want to actually try this, but for me this is an invitation to use parapsychology as control group for science, and to ponder a general heuristic for crudely estimating the soundness of academic fields for outsiders.

One reason we trust that physicists and chemists have some understanding of their subjects is that they produce valuable technological spinoffs with concrete and measurable economic benefit. In practice, I often make use of the spinoff heuristic: If an unfamiliar field has the sort of knowledge it claims, what commercial spinoffs and concrete results ought it to be producing? Do such spinoffs exist? What are the explanations for their absence?

For psychology, I might cite systematic desensitization of specific phobias such as fear of spiders, cognitive-behavioral therapy, and military use of IQ tests (with large measurable changes in accident rates, training costs, etc). In financial economics, I would raise the hundreds of billions of dollars invested in index funds, founded in response to academic research, and their outperformance relative to managed funds. Auction theory powers tens of billions of dollars of wireless spectrum auctions, not to mention evil dollar-auction sites

This seems like a great task for crowdsourcing: the cloud of LessWrongers has broad knowledge, and sorting real science from cargo cult science is core to being Less Wrong. So I ask you, Less Wrongers, for your examples of practical spinoffs (or suspicious absences thereof) of sometimes-denigrated fields in the comments. Macroeconomics, personality psychology, physical anthropology, education research, gene-association studies, nutrition research, wherever you have knowledge to share.

ETA: This academic claims to be trying to use the Bem methods to predict roulette wheels, and to have passed statistical significance tests on his first runs. Such claims have been made for casinos in the past, but always trailed away in failures to replicate, repeat, or make actual money. I expect the same to happen here. 

Verifying Rationality via RationalPoker.com

32 Louie 25 March 2011 04:32PM

Related to: Problem of verifying rationality

We're excited to announce the (soft) launch of RationalPoker.com! It's a new guide developed by me, Zvi, Kevin, and patrissimo detailing how to use online poker as rationality training to conquer your cognitive biases. We want our community to go from knowing a lot about cognitive biases to actually having a training method that allows us to integrate that knowledge into our habits -- truly reducing biases instead of just leaving us perpetually lamenting our flawed brain-ware. In the coming weeks, we'll be making the case that online poker is a useful rationalist pursuit along with developing introductory "How To" material that allows those who join us to play profitably.

We want to make sure we aren’t wasting our time practicing an ungrounded art with methods that don’t work. Poker gives us an objective way to test x-rationality. The difference between winning and losing in poker once you know a small amount of domain-specific knowledge is due to differing levels of rationality. Our site will be presenting the case that a strong rationalist who can act on their knowledge of cognitive biases (a defining feature of x-rationality but not traditional rationality) should have a distinct advantage. We'll be offering the connecting material between the sequences and online poker to teach you how to apply knowledge of cognitive biases to poker in a way that verifies your current level of rationality and naturally teaches you to improve your rationality over time.

Incidentally, this also presents a solution for those of us looking to earn money from anywhere with a flexible schedule that leaves time for outside interests.

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Frugality and working from finite data

27 Snowyowl 03 September 2010 09:37AM

The scientific method is wonderfully simple, intuitive, and above all effective. Based on the available evidence, you formulate several hypotheses and assign prior probabilities to each one. Then, you devise an experiment which will produce new evidence to distinguish between the hypotheses. Finally, you perform the experiment, and adjust your probabilities accordingly. 

So far, so good. But what do you do when you cannot perform any new experiments?

This may seem like a strange question, one that leans dangerously close to unprovable philosophical statements that don't have any real-world consequences. But it is in fact a serious problem facing the field of cosmology. We must learn that when there is no new evidence that will cause you to change your beliefs (or even when there is), the best thing to do is to rationally re-examine the evidence you already have.

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The role of mathematical truths

14 SilasBarta 24 April 2010 04:59PM

Related to: Math is subjunctively objective, How to convince me that 2+2=3


Elaboration of points I made in these comments: first, second


TL;DR Summary: Mathematical truths can be cashed out as combined claims about 1) the common conception of the rules of how numbers work, and 2) whether the rules imply a particular truth.  This cashing-out keeps them purely about the physical world and eliminates the need to appeal to an immaterial realm, as some mathematicians feel a need to.


Background: "I am quite confident that the statement 2 + 3 = 5 is true; I am far less confident of what it means for a mathematical statement to be true." -- Eliezer Yudkowsky


This is the problem I will address here: how should a rationalist regard the status of mathematical truths?  In doing so, I will present a unifying approach that, I contend, elegantly solves the following related problems:


- Eliminating the need for a non-physical, non-observable "Platonic" math realm.

- The issue of whether "math was true/existed even when people weren't around".

- Cashing out the meaning of isolated claims like "2+2=4".

- The issue of whether mathematical truths and math itself should count as being discovered or invented.

- Whether mathematical reasoning alone can tell you things about the universe.

- Showing what it would take to convince a rationalist that "2+2=3".

- How the words in math statements can be wrong.

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TakeOnIt: Database of Expert Opinions

17 Eliezer_Yudkowsky 05 January 2010 08:54PM

Ben Albahari wrote to tell us about TakeOnIt, which is trying to build a database of expert opinions.  This looks very similar to the data that would be required to locate the Correct Contrarian Cluster - though currently they're building the expert database collaboratively, using quotes, rather than by directly polling the experts on standard topics.  Searching for "many worlds" and "zombies" didn't turn up anything as yet; "God" was more productive.

The site is open to the public, you can help catalog expert opinions, and Ben says they're happy to export the data for the use of anyone interested in this research area.

Having this kind of database in standardized form is critical for assessing the track records of experts.  TakeOnIt is aware of this.

Two Truths and a Lie

59 Psychohistorian 23 December 2009 06:34AM

Response to Man-with-a-hammer syndrome.

It's been claimed that there is no way to spot Affective Death Spirals, or cultish obsession with the One Big Idea of Everything. I'd like to posit a simple way to spot such error, with the caveat that it may not work for every case.

There's an old game called Two Truths and a Lie. I'd bet almost everyone's heard of it, but I'll summarize it just in case. A person makes three statements, and the other players must guess which of those statements is false. The statement-maker gets points for fooling people, people get points for not being fooled. That's it. I'd like to propose a rationalist's version of this game that should serve as a nifty check on certain Affective Death Spirals, runaway Theory-Of-Everythings, and Perfectly General Explanations. It's almost as simple.

Say you have a theory about human behaviour. Get a friend to do a little research and assert three factual claims about how people behave that your theory would realistically apply to. At least one of these claims must be false. See if you can explain every claim using your theory before learning which one's false. 

If you can come up with a convincing explanation for all three statements, you must be very cautious when using your One Theory. If it can explain falsehoods, there's a very high risk you're going to use it to justify whatever prior beliefs you have. Even worse, you may use it to infer facts about the world, even though it is clearly not consistent enough to do so reliably. You must exercise the utmost caution in applying your One Theory, if not abandon reliance on it altogether. If, on the other hand, you can't come up with a convincing way to explain some of the statements, and those turn out to be the false ones, then there's at least a chance you're on to something.

Come to think of it, this is an excellent challenge to any proponent of a Big Idea. Give them three facts, some of which are false, and see if their Idea can discriminate. Just remember to be ruthless when they get it wrong; it doesn't prove their idea is totally wrong, only that reliance upon it would be.

Edited to clarify: My argument is not that one should simply abandon a theory altogether. In some cases, this may be justified, if all the theory has going for it is its predictive power, and you show it lacks that, toss it. But in the case of broad, complex theories that actually can explain many divergent outcomes, this exercise should teach you not to rely on that theory as a means of inference. Yes, you should believe in evolution. No, you shouldn't make broad inferences about human behaviour without any data because they are consistent with evolution, unless your application of the theory of evolution is so precise and well-informed that you can consistently pass the Two-Truths-and-a-Lie Test.

Test Your Calibration!

19 alyssavance 11 November 2009 10:03PM

In my journeys across the land, I have, to date, encountered four sets of probability calibration tests. (If you just want to make bets on your predictions, you can use Intrade or another prediction market, but these generally don't record calibration data, only which of your bets paid out.) If anyone knows of other tests, please do mention them in the comments, and I'll add them to this post. To avoid spoilers, please do not post what you guessed for the calibration questions, or what the answers are.

The first, to boast shamelessly, is my own, at http://www.acceleratingfuture.com/tom/?p=129. My tests use fairly standard trivia questions (samples: "George Washington actually fathered how many children?", "Who was Woody Allen's first wife?", "What was Paul Revere's occupation?"), with an emphasis towards history and pop culture. The quizzes are scored automatically (by computer) and you choose whether to assign a probability of 96%, 90%, 75%, 50%, or 25% to your answer. There are five quizzes with fifty questions each: Quiz #1, Quiz #2, Quiz #3, Quiz #4 and Quiz #5.

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Paper: Testing ecological models

0 brian_jaress 27 August 2009 10:12PM

You may be interested in a paper of medium age I just read. Testing ecological models: the meaning of validation (PDF) tackles a problem many of you are familiar with in a slightly different context.

To entice you to read it, here are some quotes from its descriptions of other papers:

Holling (1978) pronounced it a fable that the purpose of validation is to establish the truth of the model…

Overton (1977) viewed validation as an integral part of the modelling process…

Botkin (1993) expressed concern that the usage of the terms verification and validation was not consistent with their logical meanings…

Mankin et al. (1977) suggested that the objectives of model-building may be achieved without validating the model…

I have another reason for posting this; I’m looking for more papers on model validation, especially how-to papers. Which ones do you consider most helpful?

Toxic Truth

12 MichaelHoward 11 April 2009 11:25AM

For those who haven't heard about this yet, I thought this would be a good way to show the potentially insidious effect of biased, one-sided analysis and presentation of evidence under ulterior motives, and the importance of seeking out counter-arguments before accepting a point, even when the evidence being presented to support that point is true.

"[DHMO] has been a part of nature longer than we have; what gives us the right to eliminate it?" - Pro-DHMO web site.

DHMO (hydroxilic acid), commonly found in excised tumors and lesions of terminal lung and throat cancer patients, is a compound known to occur in second hand tobacco smoke. Prolonged exposure in solid form causes severe tissue damage, and a proven link has been established between inhalation of DHMO (even in small quantities) and several deaths, including many young children whose parents were heavy smokers.

It's also used as a solvent during the synthesis of cocaine, in certain forms of particularly cruel and unnecessary animal research, and has been traced to the distribution process of several cases of pesticides causing genetic damage and birth defects. But there are huge political and financial incentives to continue using the compound.

There have been efforts across the world to ban DHMO - an Australian MP has announced a campaign to ban it internationally - but little progress. Several online petitions to the British prime minister on this subject have been rejected. The executive director of the public body that operates Louisville Waterfront Park was actually criticised for posting warning signs on a public fountain that was found to contain DHMO. Jacqui Dean, New Zealand National Party MP was simily told "I seriously doubt that the Expert Advisory Committee on Drugs would want to spend any time evaluating that substance".

If you haven't guessed why, re-read my first sentence then click here.

HT the Coalition to Ban Dihydrogen Monoxide.

[Edit to clarify point:] I'm not saying truth is in any way bad. Truth rocks. I'm reminding you truth is *not sufficient*. When they're given treacherously or used recklessly, truth is as toxic as hydroxilic acid.

Follow-up to: Comment in The Forbidden Post.

Ask LW: What questions to test in our rationality questionnaire?

15 AnnaSalamon 29 March 2009 12:03PM


We’ve had quite a bit of discussion around LW, and OB, on the questions:

  • Is there a robust trait, “rationality”, that predicts accurate belief-formation in humans? 
  • If so, how can we measure it?  And what kinds of training might help?
  • Also, does “rationality” in the above sense help people achieve other goals, such as income, happiness, personal growth, positive relationships, or world-saving?

Rationalists that we are, it’s time to put our experiments where our mouths are.  So here’s my plan:

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