Monthly Archives: February 2009

Near-Far Like Drunk Darts?

From a recent book review:

Jonah Lehrer's mission in The Decisive Moment is to help us determine when to override our instincts and when to let them run. … One of Lehrer's interesting recommendations [is]: trust your emotions in situations where you have had a lot of experience, since this is when [your brain is] … best equipped to warn you of any deviations from their established patterns. In novel situations, on the other hand, such as when playing a new game or considering a risk to your health, it is a good idea to take a step back and do the maths, even though your emotional brain will tell you it knows better.

Macroeconomists have seen lots of precedents for this economic crisis; this isn't too far out of line from what they've seen before elsewhere. I've heard some macro folk complain that bigshot macroeconomist advice for us-now differs substantially from what they've written about there-then, i.e., about how others should have dealt with similar problems at other times.  Apparently they give different advice when a crisis is seen as "near" versus "far."  Which advice is better?

The quote above suggests this is like asking if you should drink before competing in a darts championship. If you've always practiced darts while drunk, you may be better at darts when drunk than sober; in which case you should compete drunk. Similarly, if macroeconomists have developed most of their expertise while considering events in far mode, they might give better advice when in far than near mode.  In which case we are getting bad advice.

Perhaps macroeconomists would give even better advice if they had trained in a near mode, just as you might compete better at darts if you'd trained sober.  (At least they might if my far-image near-decision speculation is correct.)  But once the training mode has been chosen, and it is time to act, that option may be no longer available.

GD Star Rating
loading...
Tagged as: , ,

The Most Frequently Useful Thing

What's the most frequently useful thing you've learned on OB – not the most memorable or most valuable, but the thing you use most often?  What influences your behavior, factors in more than one decision?  Please give a concrete example if you can.  This isn't limited to archetypally "mundane" activities: if your daily life involves difficult research or arguing with philosophers, go ahead and describe that too.

Continue reading "The Most Frequently Useful Thing" at Less Wrong »

GD Star Rating
loading...

The Most Important Thing You Learned

My current plan does still call for me to write a rationality book – at some point, and despite all delays – which means I have to decide what goes in the book, and what doesn't.  Obviously the vast majority of my OB content can't go into the book, because there's so much of it.

So let me ask – what was the one thing you learned from my posts on Overcoming Bias, that stands out as most important in your mind?

Continue reading "The Most Important Thing You Learned" at Less Wrong »

GD Star Rating
loading...

Avoid Identifying With Anything?

From Paul Graham's recent essay:

I think what religion and politics have in common is that they become part of people's identity, and people can never have a fruitful argument about something that's part of their identity. By definition they're partisan.

Which topics engage people's identity depends on the people, not the topic. For example, a discussion about a battle that included citizens of one or more of the countries involved would probably degenerate into a political argument. But a discussion today about a battle that took place in the Bronze Age probably wouldn't. No one would know what side to be on. So it's not politics that's the source of the trouble, but identity. When people say a discussion has degenerated into a religious war, what they really mean is that it has started to be driven mostly by people's identities. . . .

The most intriguing thing about this theory, if it's right, is that it explains not merely which kinds of discussions to avoid, but how to have better ideas. If people can't think clearly about anything that has become part of their identity, then all other things being equal, the best plan is to let as few things into your identity as possible.

Most people reading this will already be fairly tolerant. But there is a step beyond thinking of yourself as x but tolerating y: not even to consider yourself an x. The more labels you have for yourself, the dumber they make you.

Via Andy McKenzie.

GD Star Rating
loading...
Tagged as:

Tell Your Rationalist Origin Story… at Less Wrong

(A beta version of Less Wrong is now live, no old posts imported as yet.  Some of the plans for what to do with Less Wrong relative to OB have been revised by further discussion among Robin, Nick, and myself, but for now we're just seeing what happens once LW is up – whether it's stable, what happens to the tone of comments once threading and voting is enabled, etcetera.

Posting by non-admins is disabled for now – today we're just testing out registration, commenting, threading, etcetera.)

To break up the awkward silence at the start of a recent Overcoming Bias meetup, I asked everyone present to tell their rationalist origin story – a key event or fact that played a role in their becoming rationalists.  This worked surprisingly well.

I think I've already told enough of my own origin story on Overcoming Bias: how I was digging in my parents' yard as a kid and found a tarnished silver amulet inscribed with Bayes's Theorem, and how I wore it to bed that night and dreamed of a woman in white, holding a leather-bound book called Judgment Under Uncertainty: Heuristics and Biases (eds. D. Kahneman, P. Slovic, and A. Tversky, 1982)… but there's no need to go into that again.

So, seriously… how did you originally go down that road?

Continue reading "Tell Your Rationalist Origin Story" at Less Wrong »

GD Star Rating
loading...

What is Gossip For?

It makes sense to listen to gossip in order to keep track of what folks are up to.  But it seems the main reason we listen to gossip is to prepare to speak gossip, in jockeying for status:

We have consistently found that people are most interested in gossip about individuals of the same sex as themselves who happen to be around their own age. We have also found that information that is socially useful is always of greatest interest to us: we like to know about the scandals and misfortunes of our rivals and of high-status people because this information might be valuable in social competition. Positive information about such people tends to be uninteresting to us. Finding out that someone already higher in status than ourselves has just acquired something that puts that person even further ahead of us does not supply us with ammunition that we can use to gain ground on him. Conversely, positive information about our friends and relatives is very interesting and likely to be used to our advantage whenever possible. 

For example, in studies that my colleagues and I published in 2002 and in 2007 in the Journal of Applied Social Psychology, we consistently found that college students were not much interested in hearing about academic awards or a large inheritance if it involved one of their professors and that they were also not very interested in passing that news along to others. Yet the same information about their friends or romantic partners was rated as being quite interesting and likely to be spread around.

I far prefer talking "big ideas" to gossiping, but I know that I am an outlier here, even relative to most academics. This once made me feel superior, but I now realize it puts me at a serious social disadvantage; when others see you don't gossip to monitor talk about you and to defend yourself and your allies, they feel freer to dis you and less inclined to ally with you. 
GD Star Rating
loading...
Tagged as:

Markets are Anti-Inductive

I suspect there's a Pons Asinorum of probability between the bettor who thinks that you make money on horse races by betting on the horse you think will win, and the bettor who realizes that you can only make money on horse races if you find horses whose odds seem poorly calibrated relative to superior probabilistic guesses.

There is, I think, a second Pons Asinorum associated with more advanced finance, and it is the concept that markets are an anti-inductive environment.

Let's say you see me flipping a coin.  It is not necessarily a fair coin.  It's a biased coin, and you don't know the bias.  I flip the coin nine times, and the coin comes up "heads" each time.  I flip the coin a tenth time.  What is the probability that it comes up heads?

If you answered "ten-elevenths, by Laplace's Rule of Succession", you are a fine scientist in ordinary environments, but you will lose money in finance.

In finance the correct reply is, "Well… if everyone else also saw the coin coming up heads… then by now the odds are probably back to fifty-fifty."

Recently on Hacker News I saw a commenter insisting that stock prices had nowhere to go but down, because the economy was in such awful shape.  If stock prices have nowhere to go but down, and everyone knows it, then trades won't clear – remember, for every seller there must be a buyer – until prices have gone down far enough that there is once again a possibility of prices going up.

So you can see the bizarreness of someone saying, "Real estate prices have gone up by 10% a year for the last N years, and we've never seen a drop."  This treats the market like it was the mass of an electron or something.  Markets are anti-inductive.  If, historically, real estate prices have always gone up, they will keep rising until they can go down.

Continue reading "Markets are Anti-Inductive" »

GD Star Rating
loading...

Libel, Slander, Blackmail

Bryan Caplan reminds us of a great old puzzle: why are libel, slander, and blackmail illegal? Bryan and I find it easier to understand two extreme positions than the actual intermediate mixture we have. The extremes:  

Punish Falsehood – Authorities monitor what people say and punish them for saying things authorities believe false. Of course authorities pay attention to transaction costs; it isn't feasible to react to every little falsehood. But if authorities believe something, well they believe it to be true, and so they usually expect people to be harmed by believing the opposite. When a falsehood is important enough, punish it. 

Listener Beware – It is up to listeners to decide what to believe. Speakers who are eager to be believed can, if they choose, subject themselves to penalties if they can be proved wrong. Such "fraud" penalties can even be in contracts. But since listeners can choose to ignore speakers they don't respect, and can use any basis they think appropriate to decide who to believe, it is not clear why we should risk empowering authorities to intervene further. If you hear something you think false, just say so. 

Actual policy is an odd mix of these extremes. People are free to make any strange religious or political claims, but are not free to make medical claims, claims about people, or claims at trials. Nor are folks free to be paid not to tell truths. Surely there are some implicit bias theories behind these rules, but until these theories are made more explicit it remains hard to evaluate how much sense these rules make.

Added:  In the US, alcohol companies may not buy TV ads truthfully saying most studies find people who drink more are healthier, and trial witnesses may not truthfully tell rumors they've heard about the accused.  Most comments so far basically repeat standard arguments for one or two of the extreme positions; the puzzle is how to tell when one or the other is most appropriate. 

More Added:  Bryan and I want to debate; tell us what to debate about.

GD Star Rating
loading...
Tagged as:

Formative Youth

Followup toAgainst Maturity

"Rule of thumb:  Be skeptical of things you learned before you could read.  E.g., religion."
        — Ben Casnocha

Looking down on others is fun, and if there's one group we adults can all enjoy looking down on, it's children.  At least I assume this is one of the driving forces behind the incredible disregard for… but don't get me started.

Inconveniently, though, most of us were children at one point or another during our lives.  Furthermore, many of us, as adults, still believe or choose certain things that we happened to believe or choose as children.  This fact is incongruent with the general fun of condescension – it means that your life is being run by a child, even if that particular child happens to be your own past self.

I suspect that most of us therefore underestimate the degree to which our youths were formative – because to admit that your youth was formative is to admit that the course of your life was not all steered by Incredibly Deep Wisdom and uncaused free will.

To give a concrete example, suppose you asked me, "Eliezer, where does your altruism originally come from?  What was the very first step in the chain that made you amenable to helping others?"

Then my best guess would be "Watching He-Man and similar TV shows as a very young and impressionable child, then failing to compartmentalize the way my contemporaries did."  (Same reason my Jewish education didn't take; I either genuinely believed something, or didn't believe it at all.  (Not that I'm saying that I believed He-Man was fact; just that the altruistic behavior I picked up wasn't compartmentalized off into some safely harmless area of my brain, then or later.))

It's my understanding that most people would be reluctant to admit this sort of historical fact, because it makes them sound childish – in the sense that they're still being governed by the causal history of a child.

But I find myself skeptical that others are governed by their childhood causal histories so much less than myself – especially when there's a simple alternative explanation: they're too embarrassed to admit it.

Continue reading "Formative Youth" »

GD Star Rating
loading...

What Do Schools Sell?

Major exams like the SAT or GRE are graded anonymously; info identifying test takers is hidden from test graders.  My department follows the same policy on its major “prelim” and “field” exams.  But in virtually every class, grading of homework, exams, etc. is not anonymous, even though that would be easy to arrange.  Yes class presentations and participation couldn’t be anonymous, but the rest could. Presumably the reason major exams are anonymous is to avoid even the appearance of the possibility of bias or corruption; why allow such an appearance with classes?

Also, letters of recommendations can be nearly as important as grades.  Yet most schools have zero procedures to avoid corruption there.  Students are given no guidelines or basis for comparison; no records are kept of who recommended who for what on what basis, so there isn’t any way to even look for corruption. Why so cavalier there?

Also, profs at top schools are advised to put minimal effort into teaching, as they will be evaluated mainly on their research.  So why do students pay extra to attend colleges with research-focused teachers who mostly ignore them?

As with docs and macro-economists, let me suggest people want to affiliate with prestigious others; a major product schools sell students is a direct relationship with prestigious faculty.  Anonymous class grading is avoided because it would reduce an important personal tone in the student teacher relationship; the possibility of corruption goes along with a personal connection.

Yes, colleges credential student performance, and those credentials would be more valuable if they better avoided the appearance of corruption.  But in addition to performance credentials schools are selling college students the ability to claim relationships with about fifty teachers, and to claim a closer relation with the few who write recommendation letters.  Perhaps students care about those relations nearly as much or more than they do about performance credentials.

Added: Schools also sell affiliation with other high status students.
GD Star Rating
loading...
Tagged as: ,