Monthly Archives: June 2008

Experience Increases Overconfidence

The latest Journal of Prediction Markets has a lit review on overconfidence, with a to-me surprising result: financial overconfidence increases with age, experience, and success.  Here are three investment experiments:

Kirchler and Maciejovsky (2002) …. demonstrated that subjects were overconfident in late trading periods … [but] underconfident during other trading periods. … Dittrich et al (2005) … found that age was positively correlated to overconfidence for complex tasks.  … Glaser et al (2005) … [found that financial market] professionals’ degrees of overconfidence was higher than that of the student subjects in most tasks, and it appeared that was because the "professionals are biased in job related tasks, such as forecasting real world financial time series."


A survey of German stock market forecasters conducted by Deaves et al (2005) … demonstrated that the market forecasters were overconfident in their predictions and that greater market experience and success, measured by correct predictions, increased their overconfidence.  … Markets are likely to become more overconfident when market returns are high. 

This is disturbing.  If overconfidence is positively correlated with ability, then observers can rationally take overconfidence as a signal of ability, and people can want to appear more overconfident to appear more able.  But to make this story work, somehow it should on average be easier to get away with being more overconfident when one is more experienced and successful.  How can this be?

This all seems to make it more reasonable than one might otherwise have thought to disagree about finance with older, more experienced, more successful folks.

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The Moral Void

Followup toWhat Would You Do Without Morality?, Something to Protect

Once, discussing "horrible job interview questions" to ask candidates for a Friendly AI project, I suggested the following:

Would you kill babies if it was inherently the right thing to do?  Yes [] No []

If "no", under what circumstances would you not do the right thing to do?   ___________

If "yes", how inherently right would it have to be, for how many babies?     ___________

Continue reading "The Moral Void" »

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What Would You Do Without Morality?

Followup toNo Universally Compelling Arguments

To those who say "Nothing is real," I once replied, "That’s great, but how does the nothing work?"

Suppose you learned, suddenly and definitively, that nothing is moral and nothing is right; that everything is permissible and nothing is forbidden.

Devastating news, to be sure – and no, I am not telling you this in real life.  But suppose I did tell it to you.  Suppose that, whatever you think is the basis of your moral philosophy, I convincingly tore it apart, and moreover showed you that nothing could fill its place.  Suppose I proved that all utilities equaled zero.

I know that Your-Moral-Philosophy is as true and undisprovable as 2 + 2 = 4. But still, I ask that you do your best to perform the thought experiment, and concretely envision the possibilities even if they seem painful, or pointless, or logically incapable of any good reply.

Would you still tip cabdrivers?  Would you cheat on your Significant Other?  If a child lay fainted on the train tracks, would you still drag them off?

Would you still eat the same kinds of foods – or would you only eat the cheapest food, since there’s no reason you should have fun – or would you eat very expensive food, since there’s no reason you should save money for tomorrow?

Would you wear black and write gloomy poetry and denounce all altruists as fools?  But there’s no reason you should do that – it’s just a cached thought.

Would you stay in bed because there was no reason to get up?  What about when you finally got hungry and stumbled into the kitchen – what would you do after you were done eating?

Would you go on reading Overcoming Bias, and if not, what would you read instead?  Would you still try to be rational, and if not, what would you think instead?

Close your eyes, take as long as necessary to answer:

What would you do, if nothing were right?

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Average Your Guesses

What percentage of the world’s airports are in the USA? (Answer below the fold.)

Take a guess. Now, take another guess, different from the first one, and average them. According to research reported on in The Economist, averaging the 2nd guess improves accuracy by 6.5%. Better still, wait 3 weeks before taking a second guess. Averaging now improves accuracy by 16%. (Story found via Slashdot.)

Here is the full report from Pschological Science.  Some excerpts:

It is important that neither group knew they would be required to furnish a second guess, as this precluded subjects from misinterpreting their task as being to specify the two endpoints of a range.

That could make it a little tricky to do this on your own; you have to try to make your first guess as good as you can, and then start fresh for the second guess.

This benefit of averaging cannot be attributed to subjects’ finding more information between guesses, because second guesses were less accurate than first guesses

Hmmm, how can second guesses be less accurate than first guesses, yet averaging them is more accurate than either? I suppose it means that the two guesses tend (on average) to bracket the correct answer, with the second guess farther away than the first one. That means that your first instinct to improve your guess is more likely than not to be in the correct direction, but go too far. Knowing this might allow you to improve your guesses even more.

Oh, and as for the airports? According to the CIA World Factbook, there are 14,947 airports in the U.S., and 49,024 in the whole world, so 30% of the world’s airports are in the U.S. For the record, I guessed 25%, and then 15%, so averaging didn’t help me. But in general this might be a useful trick to easily improve guesses.

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The Opposite Sex

Some observations on sex and gender:

* Yes, there are two different sexes in the human species; and they differ by the presence or absence of entire complex adaptations.  Just as men lack uteruses and women lack testicles, so too, there are differences of psychological machinery as well.

* Defns:  "Sex" is the biological difference.  "Gender" is a meme, a cultural concept of sex.

* A good deal (perhaps a majority) of what we think of as "manly" or "womanly" is gender rather than sex, just because it is so much easier to create and transmit cultural information than biological information.  A man in Saudi Arabia may have a very different concept of what it means to be male than a man in New Zealand.

* Gender concepts are built around sex differences – not faithfully reporting them, but accreted around them.  You couldn’t just swap the "man" and "woman" concepts in Saudi Arabia, or New Zealand either, and end up with a stable meme.  For more on this see John Tooby and Leda Cosmides’s "The Psychological Foundations of Culture".

* Understanding the opposite sex is hard.  Not as hard as understanding an AI, but it’s still attempting empathy across a brainware gap: trying to use your brain to understand something that is not like your brain.

* Despite everything I’ve read on evolutionary psychology, and despite having set out to build an AI, and despite every fictional novel I’d read that tried to put me into the life-experience of a woman, when I tried to use that "knowledge" to guide my interactions with my girlfriend, it still didn’t work right.

Continue reading "The Opposite Sex" »

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The Conversation So Far

(I paraphrase.)

After a year of Robin pestering co-blogger Eliezer "Can we talking about singularity on the blog now, can we?" and Eliezer saying "Not yet," Robin speaks up on the occasion of his IEEE Spectrum singularity article:

Robin: Hey Eliezer, I see you’ve been talking for years about an AI-singularity.  Have a look; I’ve analyzed the history of previous "singularities" (as Vinge defines the term) and can use that to forecast the timing, speedup, and transition inequalities of the next singularity.  I can also find a tech that looks pretty likely to appear within the predicted time-frame, and an economic analysis suggests it could plausibly deliver the forecasted speedup.  And this tech is a kind of AI! 

  I really don’t have time to talk, but you are looking at untrustworthy surface analogies, not reliable deep causes.  My deep insight is that optimization processes are more powerful the smaller and better is their protected meta-level, and history is divided into epochs according to the arrival of new long-term optimization processes, and to a lesser extent their meta-level innovations, after each of which ordinary innovation rates speed up.  The two optimization processes so far were natural selection and cultured brains, and key meta-innovations were cells, sex, writing, and scientific thinking. I’m talking about a future singularity due to a transistor-based machine with no (and therefore the best) protected meta-level.  My deep insight suggests this would have an extremely large speedup and transition inequality. 

Robin:  This history of when innovation rates sped up by how much just doesn’t seem to support your claim that the strongest speedups are caused by and coincide with new optimization processes, and to a lesser extent protected meta-level innovations.  There is some correlation, but it seems weak.  And since you don’t argue for a timing for your postulated singularity, why can’t we think yours will happen after the singularity I outline? 

Eliezer:  Sorry, no time to talk.

To be continued. 

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Glory vs. Relations

From a thoughtful essay by Christina Sommers: 

MIT biologist Nancy Hopkins, … (a prominent accuser of Harvard president Lawrence Summers … [who suggested] men and women might have different propensities and aptitudes), points to the hidden sexism of the obsessive and competitive work ethic of institutions like MIT.  "It is a system," Hopkins says, "where winning is everything, and women find it repulsive. … The list of cultural norms that appear to disadvantage women … includes the favoring of disciplinary over interdisciplinary research and publications, and the only token attention given to teaching and other service" …

If asked to make a drawing, little girls almost always create scenes with at least one person, while males nearly always draw things – cars, rockets, or trucks. … Among primates, including our closest relations the chimpanzees, males are more technologically innovative, while females are more involved in details of family life. … After two major waves of feminism, women still predominate – sometimes overwhelmingly – in empathy-centered fields such as early-childhood education, social work, veterinary medicine, and psychology, while men are over-represented in the "systematizing" vocations such as car repair, oil drilling, and electrical engineering. …

[Consider] women’s [amazing] progress in veterinary medicine …

Continue reading "Glory vs. Relations" »

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2-Place and 1-Place Words


Followup toThe Mind Projection Fallacy, Variable Question Fallacy

I have previously spoken of the ancient, pulp-era magazine covers that showed a bug-eyed monster carrying off a girl in a torn dress; and about how people think as if sexiness is an inherent property of a sexy entity, without dependence on the admirer.

“Of course the bug-eyed monster will prefer human females to its own kind,” says the artist (who we’ll call Fred); “it can see that human females have soft, pleasant skin instead of slimy scales.  It may be an alien, but it’s not stupid – why are you expecting it to make such a basic mistake about sexiness?”

What is Fred’s error?  It is treating a function of 2 arguments (“2-place function”):

Sexiness: Admirer, Entity -> [0, ∞)

As though it were a function of 1 argument (“1-place function”):

Sexiness: Entity -> [0, ∞)

If Sexiness is treated as a function that accepts only one Entity as its argument, then of course Sexiness will appear to depend only on the Entity, with nothing else being relevant.

When you think about a two-place function as though it were a one-place function, you end up with a Variable Question Fallacy / Mind Projection Fallacy.  Like trying to determine whether a building is intrinsically on the left or on the right side of the road, independent of anyone’s travel direction.

Continue reading "2-Place and 1-Place Words" »

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Caution Kills When Fighting Malaria

Mosquito induced malaria kills over 1 million people each year.

Fortunately, genetic engineering could greatly reduce this death toll.  As BBC news reports “A genetically modified (GM) strain of malaria-resistant mosquito has been created that is better able to survive than disease-carrying insects.  It gives new impetus to one strategy for controlling the disease: introduce the GM insects into wild populations in the hope that they will take over.”

Alas, it will likely take “10 to 20 years before transgenic mosquitoes are released into nature,” in part because “It’s very difficult to predict what will happen when we release these things.” 

Before releasing the mosquitoes scientists first want to conduct research that “address all the social, ethical and legal issues associated with releasing transgenic organisms into the environment.” (Emphasis mine.)

I’m not a biologist, but I find it almost impossible to believe that the expected negative side effects  of releasing the GM mosquitoes could even come close to the harm now caused by malaria.  If, therefore, GM mosquitoes could significantly reduce malaria deaths they should be quickly released into the environment even if there is a high chance that the GM mosquitoes will cause serious “social, ethical and environmental harm.”

I suspect that those who would take a cautious approach to releasing GM mosquitoes suffer from status quo bias and give much greater weight to avoiding new negative consequences than they do to eliminating existing harms.  Others, I suspect, give less relative weight to the existing harms because these harms are "natural" whereas any damage that comes about as a side effect of releasing GM mosquitoes would be man-made and thus unnatural.

If a researcher working on the malaria fighting mosquitoes is reading this post I urge you to take it upon yourself to release the GM mosquitoes as soon as they have a high probability of working even if doing so would violate the law and your colleagues’ trust.  You probably won’t be able to release them over a wide area.  But if you can show that the GM mosquitoes are safe and effective then they will likely be released on a large scale sooner than if you had not acted.

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To What Expose Kids?

State courts recently rebuked Texas Child Protective Services and told them to return 440 kids to their polygamous Mormon parents.  The main complaint I’ve heard is that these teen girls can not really consent to polygamous marriage because they were not exposed enough to the rest of the world.   For example, Will Wilkinson:

About kids raised on isolated compounds by religious fanatics … It is tyrannical for parents to attempt to reproduce their ideologies and prejudices in their children, especially when this requires social isolation and emotional coercion. … They just have a political right to not be stopped, within bounds.  Many parents, though they intend the opposite, are in fact guilty of wrongful disregard for the development of their children’s psychological freedom.

Of course responsible parents know they should expose kids to more than just the local neighborhood.  But parents’ judgments on optimal exposure surely depend on their judgments about that outside world.  Someone who sees outsiders as mostly immoral heathens will choose less exposure than we as outsiders would choose for those same kids. 

So is the principle here that parents should go beyond their simple judgment when choosing to what to expose our kids?  For example, should we let polygamists argue for their way of life directly to our kids?  Should we let pedophiles argue their case directly to our kids?  Or is the principle here that we know we are right and those other parents are wrong, obligating us to make those parents give their kids what we judge best?

I wonder, could different cultures make a deal where they each give the other cultures X hours to make their case to their kids?   Of course with many cultures of differing sizes there’d be the issue of what fraction of that time each culture gets to use.  And of course unreasonable cultures might be excluded from the deal. (But what criteria could characterize "reasonable"?)  And if such a deal is not possible, even among some reasonable cultures, what exactly would that say about what we think about who should be exposed to what? 

Added 29June:  Will responds here.

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