Say what?

Evolutionary psychology is criticized a lot for making it too easy to generate hypotheses which are unfalsifiable. You observe a trait x, therefore trait x must be adaptive; here's a story explaining why it's adaptive. For the record, I definitely do not agree that evolutionary psychology is unscientific. It is. It is a subject that studies testable hypotheses. However, it is also being outrageously oversold in the popular media, which are chock-full of unfalsifiable evolutionary just-so stories. For example, Christopher Ryan, author of Sex at Dawn, writes this:

Not only does one sperm compete against millions of your own, but millions of other men. Considering women’s immune system treats sperm as invaders, women select their mates on a cellular level regardless of what their instincts might tell them. (...) not only are women naturally promiscuous, but men are attracted to other men having sex with women (...) This is why women scream during sex--to attract more men to join the fight.

Color me unconvinced.

Rationalizing cruelty, again

James Lewis's essay in which he argues that the ideology of fascism is largely a complex way of rationalizing a desire to see others suffer is both very interesting and incredibly naive. It's interesting because the point that our beliefs should not be taken at face value because they are often designed to be fronts for some unspoken desires isn't argued often enough. It's naive because it grossly underestimates the scope of this very phenomenon. For example, Lewis seems to believe that Americans are immune to the impulse of gratuitous cruelty. Naive doesn't even begin to describe such belief. For another example, Lewis concentrates on fringe or extremist beliefs (fascism, communism, Islamic fundamentalism etc.), not realizing that ideologies designed mainly to rationalize cruelty are (and always have been) very much part of mainstream. For instance, a lot of religion-based morality, or the way we think criminals should be punished, are really just sophisticated ways of allowing people to act on their sadistic impulses while still believing they're fundamentally good people ("C'mon, I'm only stoning him to death because it pleases God, not because I like stoning people to death!")

A graph is worth a thousand words: World War II and the population of Warsaw

(Source: Wikipedia.)

Stunning links

Five evidence-based ways to make yourself happier in the long run.

What's a "bond bubble," and why should we be worried about it?

Complicated mechanisms explained in simple animations. How does a sewing machine manage to knot stitches without releasing the thread? One quick look and you will know.

A moving documentary about Andrew Wiles and the quest to prove Fermat's Last Theorem.

Against banning election betting.

What would happen if businesses stopped maximizing profits and settled for "satisfactory profits" instead?

Who should exist?

Is suicide bad?

A number of months ago I wrote about gun buybacks, arguing that this policy cannot possibly do any good whatsoever. It turns out that I was dead wrong: it certainly can, and it probably does. According to a study done by Australian economists Andrew Leigh and Christine Neill, a nationwide gun buyback program implemented in Australia in 1997, which reduced the stock of firearms by about 20%, has lead to a decrease in the number of firearm suicides of as much as 74%, which translates into about 200 lives per year.

When thinking about the effects of gun buybacks on various outcomes, it never occurred to me to consider suicide--a huge omission on my part. It's clear that there should be an effect, and now we have evidence suggesting that it's there.

OK, so gun buybacks reduce the number of suicides. Is that a good thing? Why should we assume that suicide is always a bad thing?

Actually, we don't have to assume this to believe that this particular consequence of gun buybacks is beneficial. I for one don't think that every act of suicide does more harm than good. Death isn't always the worst thing that can happen. No one knows your life as well as you do, so if you think it's not worth living, you are probably right. (Note: some ethicists argue that suicide need not be a bad thing using the volenti non fit iniuria principle. I don't think this is a good argument. It works as an argument for suicide being legal, not beneficial. It's legal to drink two pints of Jameson a day; few people would argue, however, that it's a good idea to do so.)

I do think that most suicides do more harm than good though (in a social welfare meaning of the phrase), for two reasons. First, suicide victims are often dead wrong when doing their mental cost-benefit analysis trying to figure out if carrying on is worthwhile. Most of the time those mistakes are due to (very much treatable) mental conditions and/or influence of drugs. I cannot find the statistics at the moment, but I do know that in some societies very large number of suicides are directly caused by episodes of alcohol-induced psychosis, for example. Second, a suicide victim does not affect only themselves, but those around them as well, often causing them considerable pain and suffering.

Aside from all this, here's why we can be fairly sure that saving those 200 lives a year is actually a good thing: the decrease in suicides by firearms did not lead to an increase in suicides by other methods. In other words, most potential suicide victims who were all of a sudden cut off from access to guns did not use a substitute. This I think is pretty powerful evidence that many suicide decisions were incorrect (from victims' point of view), and that many acts of self-destruction were carried out only because they were too easy to execute.

Beautiful experiments in social science: Reversing the implication

People tend to make the logical error of reversing the implication, i.e. believing that "If A then B" implies "If B than A." A clever experimental design devised by psychologist Peter Cathcart Wason showed how often that mistake is made. Here's the design:

You are shown a set of four cards placed on a table, each of which has a number on one side and a colored patch on the other side. The visible faces of the cards show 1, 2, red and blue. Which card(s) should you turn over in order to test the truth of the proposition that if a card shows a 2 on one face, then its opposite face is red?

Answer given by more than 90% of participants: 2 and red. Correct answer: 2 and blue. The incorrect answer clearly stems from reversing the implication.

The opposite of truth is just as good as truth

One one of the Polish political blogs I've recently stumbled on a quote from a book written by Viktor Suvorov, a former member of the Soviet secret special-ops forces called Spetsnaz, who defected to the UK:

The most important thing is to confuse the enemy. If the operation is done with lots of Spetsnaz units, you pretend that there's really just a few of them. If the forces you're using are small, you should make the operation look large. (...) Suppose a Spetsnaz unit is to destroy a number of targets, all of them situated more or less on a straight line and in a densely populated area (for example, a pipeline, a power supply line, a highway, a few bridges, etc.). In such situation, the detonators on the explosives placed first are set to long delay, and then that delay should get shorter and shorter on the devices placed later on. In this way, the timing of the explosions will be opposite to the direction along which the unit was marching. If the unit was traveling from East to West, the explosions will start on the West first and then move Eastwards, deceiving the enemy into thinking that the unit was traveling Eastwards as well.

Now if this is actually how Spetsnaz went about deceiving the enemy then they were in dire need of an intro to game theory class. The deception strategy of telling the exact opposite of the truth can only work once; if you repeat it, your enemy will quickly catch on to what you're doing and you might as well tell them the truth outright. How long do you think you'd last in a poker game if you made large bets every time your hand was weak, and small bets every time your hand was strong? The only deception strategy that is viable in the long run is to behave in a way that does not exhibit any discernible patterns. In other words, randomly.

That's right!

(Extremely funny, though probably NSFW.)

Retroregulation

First, a great quote from Eric Falkenstein:

You might remember the SEC in penalizing famous frauds like Madoff, Bayou, and Wood River--after they were exposed as frauds by their own investors. These are the police who show up after you've tackled and hog-tied your intruder, and then take credit for putting him in jail.

In his post, Falkenstein also talks about the "flash order crash" of May 2006, when systems started failing because institutional restrictions on how trades are supposed to be routed were outdated and unprepared to deal with flash orders. The SEC's proposed solution: ban flash orders.

This illustrates two worst features of regulation: that it's always reactive, and that whenever that feature leads to widespread problems, the government answers simply by trying to outlaw the market invention that has exposed regulation's weakness. The first feature is unavoidable. The market will keep inventing things that regulators do not anticipate. But maybe the second one is not. Perhaps a scheme can be designed whereby the regulators are banned from banning things and are instead forced to improve their regulations when those are exposed as inadequate.

Yoga people

I've never taken a yoga class but I see tons people coming in and out of them all the time. Not once did I see a yoga class taker who would be overweight or anywhere close to that. Those of my friends who take yoga classes themselves tell me that this observation holds as well inside one as it does outside. If it's true in general, a likely conclusion is that yoga is much less effective in reducing weight than regular exercise (cardio plus lifting weights).

People work out for two reasons (which aren't mutually exclusive): to lose weight and to stay in shape which improves long-term health. You have to exercise very hard in order to see results in terms of losing weight; if all you want is to stay in shape, on the other hand, an equivalent of 30 minutes of cardio a day is more than enough. People who don't have to lose weight are therefore content with lighter exercise. If you could lose weight doing yoga, you would see people trying to do just that (as you do in regular gyms). The fact that you don't most likely means that you can't, and yoga is therefore chosen only by people who don't have to work out very hard.

Sound policy advice from The Onion

U.S. Agriculture Secretary: 'Aw, Let's Not Do Farming Anymore'.

I wish.

Buying votes can be a good thing

The single worst feature of democracy is that there are situations when a (sometimes overwhelming) majority of voters will oppose policy changes that are literally good for everyone (in econ jargon, they are Pareto-optimal, i.e. they make some people better off without making anyone worse off). A few months ago I wrote about a specific situation in some Polish public hospitals where it is clear that charging some people for certain surgeries would make everyone better off (and I mean everyone: doctors, hospitals, the government, and the patients, including those patients that would have to pay). And yet virtually every Polish voter and politician would vehemently oppose such change because healthcare is a right and not a commodity and how dare you even think about charging people for services they receive.

But there may be hope. Some efficient policies, while opposed by voters before they were enacted, are accepted and even liked by them after they take effect. In other words, popular opposition to efficient change is not always perpetual. Which brings me to my point: politicians should bribe voters more. In situations where it is clear that popular opposition to an efficient policy will disappear as soon as the policy starts working, politicians do not face long-term risks from advocating it and therefore could offer voters side-payments of some sort in exchange for voting in favor of such policy. It wouldn't cost them much, either; since the policy is efficient, it will generate new revenue, so the bribes can be financed through borrowing against that revenue. Also, the bribe would be a one-shot deal whereas the new revenue stream is forever.

Of course the devil is in the details; it's not at all clear to me how something like that should be done. Fortunately I'm just a blogger, not a policy engineer.

(HT: Economic Logic.)

Sometimes you see a line so stupid...

That you just can't help but spread it around for everyone to mock. Here goes:

Mr. DeLay, the Texas Republican who had been the House majority leader, crowed that he had been "found innocent." But many of Mr. DeLay's actions remain legal only because lawmakers have chosen not to criminalize them.

It's from a NYT editorial. But it's not really an editorial. It's an editorial only because it's an opinion piece written by the senior editorial staff or publisher of the New York Times.

(HT: Megan McArdle.)

One more about Newt

A few more words about Gingrich's statement I wrote about in my previous post. Was he equating Muslims with Nazis? No, he wasn't. His was making an analogy, but the analogy was not between Muslims and Nazis. He said that a mosque is to the World Trade Center site what a swastika would be to the Holocaust museum. From this, it doesn't follow that a mosque is like a swastika. Of course it's possible that deep down he does believe the latter to be true. But it's not what he said or implied, so he cannot be held responsible for having this belief.

In short, everyone is wrong. Gingrich and those who agree with him are wrong about the law. Those who criticize him for saying Muslims are like Nazis are wrong about logic.

But what does the law actually say?

Newt Gingrich has recently said, arguing against the proposed mosque near the World Trade Center site, that "Nazis don't have the right to put up a sign next to the Holocaust museum in Washington." Everyone is wondering if, in saying that, he was equating Muslims with the Nazis; no one (at least no one I've heard) is asking if he's right about what the law actually says. And, by the way, he's wrong; the Nazis do have a legal right to put up a sign next to the Holocaust museum in Washington.

Stunning links

Tax your kid's allowance.

Nerds to jocks: Get a life.

The LA Times publishes an investigative report on teacher quality. I'm waiting to hear from teacher unions about why this is an outrageously bad idea.

One of the reasons why saying that internet makes us stupid is stupid.

Drug raid finds nothing in the house, so the cops charge family with "disorderly house". Can we charge the cops with "disorderly charging?"

The legalized theft of asset forfeiture. Can we try and civilize law enforcement in this country?

When the mean is meaningless

The media often report averages of random variables without saying anything about the shape of the distribution. When the distribution is skewed, this is completely uninformative (or even highly misleading, as most people probably think of "average" as "the most typical value").

For example, the mean monthly salary in Poland is 2,600 PLN (about $830). The mean probability of survival of an airplane incident involving casualties is 38%. What does the mean actually mean here? Not much, as both distributions are positively skewed. About 2/3 of the labor force in Poland earn less than the average salary, and 40% of plane crashes have an extremely low survival rate of 0%.

Where's the risk premium?

According to a report by the Bureau of Labor Statistics, the three most dangerous jobs in America are fisherman, logger and airline pilot. To offset the risk, those jobs are also low-paying.

(HT: Economix.)

Odds that you'll die from...

I found this through Sentient Developments; don't know what the source is:

(Click to enlarge, as usual.)

I wonder what assumptions were made in calculating those odds in terms of, for example, age. The odds that you'll die from different causes are very sensitive to age; when you're 96, for example, and if we don't know anything else about you, the most likely cause of your death is pneumonia. What age were those odds calculated at--0? 30?

Another nitpick: the probability that you'll die from smallpox is not zero. It's extremely, negligibly, vanishingly small, essentially zero, zero for all practical purposes etc., but not zero. Outside the abstract realm of mathematics and logic, there is no such thing as a probability of zero or one. The probability that next Thursday, the Sun will turn into a giant pink unicorn, is not zero.

Proofs aren't meant to convince anyone

Everyone to whom it matters knows that P does not equal NP. If so, why is P vs. NP considered to be one of the most important open questions in mathematics? Why do we need to prove something everyone is already convinced is true?

This question arises from a misconception as to what it is that math does. Gian-Carlo Rota put it best:

Saying that a mathematician's job is to "prove theorems" is like saying that a novelist's job is to "write sentences."

The job of mathematics is not to verify which mathematical statements are true and which are not, but to search for reasons why true statements are true and false ones are not. The majority of original mathematical research is done not trying to settle open questions, but trying to find new and original ways of settling problems that have already been solved. Many interesting mathematical facts have been proven tens, sometimes even hundreds of times over, each time using a different method. If all mathematicians were interested in was if a statement is true, one proof would be sufficient. But when researchers are considering a mathematical statement, they are not just interested in finding out if it's true or not. They're interested in finding out exactly why it is true. Finding a proof is a necessary, though not sufficient, condition for this. In a way, for any open mathematical problem, the Holy Grail is to find the proof: one that would show both that a statement (or its negation) is true and why it is so. For example, everyone knew long time ago that polynomials of degree five are not solvable by radicals. But no one knew why until, in the process of proving this fact, Evariste Galois came up with a theory that determines a necessary and sufficient condition for a polynomial to be thus solvable, from which it becomes obvious why equations of degree greater than four are not.

Mathematicians don't know why P does not equal NP, and they are hoping that someday, one of the proofs of this proposition will answer that question. It may be unlikely that the first proof that is discovered will provide an answer; but what's certain is that there cannot be an answer without a proof of some sort. There's also another, indirect reason why proofs are important: Proofs are fruitful. They usually lead to new insights, new techniques, new theories.

For example, Gödel proved that no consistent system of axioms whose theorems can be listed by an algorithmic procedure is capable of proving all facts about the natural numbers. By proving the same fact using a very different method, Polish logician Alfred Tarski shed some light on the reason why this is true (essentially, he showed why in formal languages that are "rich enough" to contain arithmetic of natural numbers, the set of all true statements has a higher cardinality than the set of all provable statements. Since, if the notion of provability is to make any sense at all, provable statements must be true, there must exist true statements which are not provable). And by proving the same fact by yet another method, British mathematician Alan Turing came up with a brilliant formalization of the notion of computability using a profound concept of Turing machine; his new theory turned out to have a huge impact on both theory and practice of computer science.

Better strongly wrong than weakly right

Perhaps you've heard of a Christian group that predicts that the Judgment Day will happen May 21, 2011, followed by the end of the world which will occur October 21 that same year. I submit that people who say things like that are socially much more valuable than people who say things like

America will probably need some added stimulus to kick start employment, but any stimulus right now must be in growth-enabling investments that will yield more than their costs, or they just increase debt. That means investments in skill building and infrastructure plus tax incentives for starting new businesses and export promotion.

I'm saying this even though I know that the first statement will almost certainly turn out to be wrong while the second one will probably turn out right in one way or another. The difference is that, even though it's wrong, statement number one is much more informative. It is verifiable. More precisely, it is falsifiable, in a philosophy of science kind of way. It is a strong prediction, and therefore it can be shown to be wrong. We can learn from this. On the other hand, Friedman's statement can't really be falsified: it is a weak prescription, containing many qualifiers and very little detail. If you tried to follow his advice, and results were less than stellar, the vagueness of his advice will always leave him enough room to accuse you of misunderstanding it.

It's not about being right. It's all about being informative. We can learn much more from statements that are ridiculously wrong than statements that are trivially true. Saying "All else equal, setting a minimum wage higher than the market wage for unskilled labor results in increased unemployment" is much more informative (even if wrong) than saying "Yes, but in real life all else is never equal, things are complicated etc. etc."

No virtue without sacrifice

A NYT environmental blog comments on a study showing that people misperceive which actions are most efficient in terms of reducing energy consumption:

The top five behaviors listed by respondents as having a direct impact on energy savings (turning off the lights, riding a bike or using public transportation, changing the thermostat, “changing my lifestyle/not having children” and unplugging appliances or using them less) yield savings that are far outweighed by actions cited far less often, like driving a more fuel-efficient car (...) buying new bulbs or more efficient refrigerators.

Here is how the authors of the study are trying to explain this:

Relative to experts’ recommendations, participants were overly focused on curtailment rather than efficiency, possibly because efficiency improvements almost always involved research, effort and out-of-pocket costs (e.g. buying a new energy-efficient appliance), whereas curtailment may be easier to imagine and incorporate into one’s daily behaviors without any upfront costs.

I think this explanation is entirely wrong. To me, the results of the study are evidence mostly of the fact that people think of "helping the environment" not in terms of efficiency but in terms of personal moral virtue. Our brains are hardwired such that personal sacrifice is a necessary condition of moral virtue. You are not virtuous, you are not "helping," unless you are doing something that feels like a sacrifice, however small. Note that all of the items on the list of top five things perceived to have the most beneficial impact are things that require a conscious sacrifice on part of the person doing them. Constantly remembering to switch off the lights when you no longer need them feels more like a sacrifice than buying energy-efficient light bulbs, even though the latter helps more than the former. Similarly, most people will feel more like they're helping the Haiti earthquake victims if they personally volunteer to go to Port-au-Prince to dig people from under the rubble than if they donate $500 to Red Cross, again even though the latter helps more than the former.

Never forget you're talking to a bunch of six-year-olds

If yo're a politician, that is. If you do forget this, and say something that is too hard for a six year old to understand, you'll get reactions like this:

When the president skittered back from his grandiose declaration at an iftar celebration at the White House Friday that Muslims enjoy freedom of religion in America and have the right to build a mosque and community center in Lower Manhattan, he offered a Clintonesque parsing.

“I was not commenting, and I will not comment, on the wisdom of making the decision to put a mosque there,” he said the morning after he commented on the wisdom of making a decision to put a mosque there. “I was commenting very specifically on the right people have that dates back to our founding. That’s what our country is about.”

Let me be perfectly clear, Mr. Perfectly Unclear President: You cannot take such a stand on a matter of first principle and then take it back the next morning when, lo and behold, Harry Reid goes craven and the Republicans attack.

This is embarrassing, really. Dowd actually does not understand that there's a huge difference between saying "You have a legal right to do X" and "It's a great idea for you to do X, and I support it." When offered a clarification, she doesn't understand that, either, and thinks it's a retraction.

And, of course, she's not alone in her stupidity.

I deny her refutation

If you read the headlines, you might think that Rep. Maxine Waters has refuted charges brought against her by the House Ethics Committee. If you read the actual articles with said headlines, it will turn out that she hasn't really refuted those charges; she has merely denied them. It's a rather significant difference. To refute a proposition that X is to provide evidence and/or argument from which it follows that not-X. To deny a proposition that X is to stick a "not" operator to it. One takes a lot more effort than the other.

Stunning links

A good layman's overview of P vs. NP and of the recent proof that P != NP.

You probably think that venting your anger reduces your stress and prevents you from lashing out at your friends for no reason. If you do, you're wrong; venting actually increases aggressive behavior over time.

Data from almost 10,000 users of OKCupid reveal that iPhone users have 50% to 100% more sexual partners than Android users, at every age. The sample is clearly non-random though.

Andrew Gelman is angry about the soda tax. For more or less the same reasons that I am angry about it.

Subway ad

A few days ago in a NYC subway car I saw an ad that read "Cancer, this is your last stop! Get out!" I don't remember what the ad was for. Whatever it was, it doesn't seem like such a great idea. What if you notice it right before you're supposed to get off? Cancer's last stop is also your last stop. That's not going to make you feel too good.

In defense of vandalism

Remember Conservapedia? I don't know how they are doing right now, but shortly after the site was created, they were being inundated with fake entries written by the site's critics (and some of those entries were published). Not all Conservapedia's critics liked that fact; in an old post, Ed Brayton wrote

Putting up the fake entries only gives them an excuse for all of the legitimately bad entries on the site that I was criticizing. It was nothing but the cyber-equivalent of teenagers TPing someone's yard, it was juvenile and stupid and shouldn't have been done. Criticism is a good thing; vandalism is not.

I couldn't disagree more. Vandalism of this sort is a good thing. Technically speaking, the famous and brilliant Sokal Hoax was an act of vandalism; and yet it's hard to deny that it has generated genuine social good. Demonstrating that a group of people is unable to tell the difference between their own beliefs and a mockery of those beliefs provides a lot of useful information.

Scientific betting markets

As expected, Scott Aronson's bet about the newly published proof that P does not equal NP spurred a heated discussion about the bet and scientific betting in general. Aronson's summary of the discussion runs as follows:

I was hoping for some enlightening discussion about the ethics of scientific betting in general, not more comments on the real or imagined motives behind my bet. However, the actual comments I woke up to have convinced me that the critics of my bet were right. In principle, the bet seemed like a good way to answer the flood of queries about Deolalikar’s paper, and then get back to enjoying my trip. In practice, however, the way people respond to the bet depends entirely on what they think about my motives. If you don’t care about my motives, or consider them benign, then the bet probably provided a useful piece of information or (if you already knew the information) a useful corrective to hype. If, on the other hand, you think I’m arrogant, a media whore, etc., then the bet served no purpose except to confirm your beliefs. Since people (at least taking the commenters on this blog as a representative sample, admittedly a questionable assumption!) generally wish to ascribe the worst motives to me, it follows that the bet was counterproductive.

I have no reason to question Aronson's motives and, as I have said, to me his opinion has been more informative than anything else anyone has said about Delalikar's paper. But that's just me, and Aronson can be right: given the average response of his readers, his bet was indeed counterproductive. This doesn't mean, however, that a scientific betting market would also be counterproductive. As the number of market participants grows, you cannot gain notoriety by joining it, so the motive of an average participant becomes purely to try and make money. The only way to make money on an opinion is to bet on it and be right. I see no reason why such market would not work (or work just as well as other markets work, at any rate).

One of the commenters, a computer scientist Gil Kalai, spells out his reasons to believe prediction markets wouldn't work in science:

In the economics setting of “rational expectations” there is an unknown state of the world on which agents have private information. The market prizes aggregate the private information in a subtle way and reveal the true state of the world.

The principal reason that this is not relevant to scientific questions is that a basic implicit assumption in all these models is that if all the private information of agents about the state of the world will be made public, this will suffice to determine the correct state of the world. (Say with extremely high probability). The behavior of agents in the market (or in other strategic situations) give a way for the private information to aggregate as if it was common knowledge.

But, of course, this is not relevant here. Even if we know the sincere private opinion of all scientists on a question like is factoring in P (and even their opinions about opinions of others, and whatever additional information that we want, and we can even give them time to reconsider their opinions based on pinions of others etc etc…) making this private information public is not sufficient (and usually does not help) to determine the “state of the world”.

Kalai is vague about what he means by "the true state of the world." In the context of Delalikar's proof, is the true state of the world whether or not the proof is correct, or the actual reasons why the proof is correct or not? If the latter, then it's true, a betting market can't help much. But if the former, then a betting market is actually more informative than "making all private information of participants public," for three reasons. First, a betting market allows for expressing beliefs that can't be supported by a rational argument ("I just have a strong hunch"). Second, betting markets convey information more efficiently than public revelation of private knowledge. The amount of all private knowledge relevant to a question as complex as "P versus NP" is so huge that no individual can possibly process all of it. Market prices compress all that information into signals that are much easier to process. An third, a scientific prediction market would offer information about open scientific questions in the form that would be accessible to everyone, not only scientists. As I've said before, to me as a theoretical computer science ignoramus, Aronson's bet is actually much more informative that a detailed refutation of Delalikar's proof, because I have no qualifications to judge the technical details. I have no idea why a proof that shows 3SAT is not in P should fail for problems like 2SAT and XOR-SAT. In fact, I barely know what 3SAT, 2SAT and XOR-SAT even mean. But I do know the exact meaning of $200,000.

Engagement rings follow-up

A discussion with a commenter about my post on engagement rings made me realize that, in that post, I fell far short of making myself clear. Here are some clarifications.

First, I am only wondering why engagement rings are (expected to be) expensive, not why they're there at all. If the custom were to give beautiful but inexpensive rings, there would be no question to ponder. Cheap talk requires no explanation; no one wonders why we say "Thank you" and "Good morning." But when willingness to pay comes into the picture, things need explaining, because we're willing to pay only for things we value.

My commenter explains the fact that engagement rings are expensive and that only men are expected to give them by the fact that, historically, "men have always had more access to material goods, and women have traditionally been denied the ability to own them or to have sole discretion regarding their use" and that men (as opposed to women) have traditionally been taught to show how much they value things through monetary signals. However, assuming those facts are true as empirical observations (for the record, I think the first one is while the second one is not), their existence requires its own explanation: why have things historically been this particular way and not any other? Is it just an accident of history, or are there some systematic reasons behind it?

Also for the record, I think the causal narrative I've presented in my post (that expensive engagement rings are insurance for women against losing their virginity without getting anything in return) is really only a small part of the story. The big picture is biology. In strictly biological terms, female reproductive capacity is a scarce resource while male is not. To be blunt: sperm is cheap, eggs are expensive. This is why men compete over women and not the other way around. The fact that this is so, by the way, is not a social construct: in every known human culture, men compete for mates and women choose them. In our particular culture, one of the means through which men signal their "mating value" to women in this competition, are engagement rings.

Each transaction has at least two sides. I don't think that, if women (on average) didn't care one bit about the price of engagement rings, the custom of buying expensive rings would have survived this long.

Engagement rings have outlived their purpose. And are alive and well.

The custom of men giving their sweethearts expensive rings on engagement developed in the US soon after the courts stopped hearing "breach of promise" cases. Those cases were brought by females who got engaged and had sex with their partners, and then said partners abandoned them, leaving them, as non-virgins, in a lot tougher situation on the marriage market then they were in before. Court enforcement in the "breach of promise" cases worked for a while, but the courts were soon enough annoyed with the nature of these cases and the media notoriety they brought, and simply stopped hearing them.

To fill the void, society came up with the clever institution of an expensive engagement ring. It basically works as a large, non-refundable deposit as an advance of marriage. If the engaged couple has sex and then the guy disappears, the girl gets to keep the ring. So, the fact that the guy is giving an expensive ring in the first place is a credible signal that he will not be trying to flee after all. Worked like a charm, too.

But, it's hard not to notice that since then times have changed, a lot. Nowadays, an overwhelming majority of women who get married are not virgins, and an overwhelming majority of men who get married do not care much either way. And yet engagement rings are still around, even more expensive than ever. Why?

From the "I wish I'd said this" file

Today's quote comes from an essay by Steven Pinker in which he criticizes the ridiculous notion that internet makes people stupid:

Media critics write as if the brain takes on the qualities of whatever it consumes, the informational equivalent of "you are what you eat." As with primitive peoples who believe that eating fierce animals will make them fierce, they assume that watching quick cuts in rock videos turns your mental life into quick cuts or that reading bullet points and Twitter postings turns your thoughts into bullet points and Twitter postings.

Does P != NP and why do some people not understand the point of making bets

Earlier this week, an HP Labs researcher Vinay Deolalikar has announced that he found the Holy Grail of computer science: a proof that P does not equal NP. ("P versus NP" is a problem about computational difficulty of solving problems. See here.) Deolalikar's paper has only been out there for about two days, so we don't know for sure if his proof is actually correct (and if not, whether it's fixable). After skimming it, computer scientist Scott Aronson had this to say:

In fact, I could think of only one mechanism to communicate my hunch about Deolalikar’s paper in a way that everyone would agree is (more than) fair to him, without having to invest the hard work to back my hunch up. And thus I hereby announce the following offer:

If Vinay Deolalikar is awarded the $1,000,000 Clay Millennium Prize for his proof of P≠NP, then I, Scott Aaronson, will personally supplement his prize by the amount of $200,000.

I’m dead serious—and I can afford it about as well as you’d think I can.

Maybe it's just me--but I think Aronson's statement is perfectly clear and incredibly informative (in fact, to me, it is more informative than any non-commital statement made by someone who has actually analyzed the paper in full detail could ever be, because I'm completely unqualified to judge the merits). However, a reaction of one of Aronson's commenters is I think symptomatic of a curious attitude of abhorrence and incomprehension that a lot of people display towards betting on one's beliefs. The commenter calls Aronson's post "nasty" and says:

I do not see why you should “win” a game that you do not participate; you “win” a lot of games in which you do participate. And if you really really want to express your honest opinion without being nasty, how about: “In my opinion, it is very unlikely that the argument will stand”.

How is betting a very large amount of money on your belief "not participating?" And how on Earth is saying "In my opinion it is very unlikely that X" the same thing as betting $200,000 on the fact that not-X?

The fact is that serious bets convey large amounts of information. The reason for this is twofold. First, there are two dimensions to every opinion: its meaning and its strength. Its meaning is simply what a given opinion says. Its strength is the likelihood that the person holding an opinion (implicitly) assigns to the opinion being true. As it is, people tend to egregiously misreport the strength of their opinions in non-commital statements. That's why commitment, monetary or otherwise, works.

If you were a bank, would you do that?

The financial markets of Central and Eastern European countries have manufactured a credit bubble of their own design: consumer loans denominated in foreign currency. What this means is that banks operating in, say, Hungary, have been loaning money to Hungarians; but instead of forints, they have been denominating the loans in non-Hungarian currencies (mostly euros and Swiss francs). Those loans became hugely popular for several reasons. First, those countries have had a large demand for credit but relatively small stocks of domestic capital. Second, foreign currency loans were cheaper to borrowers than loans in their native currencies, because local currencies had higher inflation rates as well as interest rates. In addition, some of those native currencies (such as the Polish zloty) have been slowly but constantly gaining value against the euro, which made euro loans get even cheaper over time.

But, of course, this has a flip side: if your home currency suddenly loses value against the currency that your loan is denominated in, your payments suddenly increase. This is exactly what happened when the global crisis started: currency traders started selling Eastern European currencies in a panic, and lots of borrowers in those countries saw their monthly loan payments soar by as much as 50%. A lot of them defaulted (about 6-7%). Countries in which the share of foreign currency loans in their total credit market was the largest (such as Latvia with 90%, Hungary with 63% or Romania with about 60%) had to request assistance from the IMF to cope with the crash.

My question is: in the pre-crisis period, why were banks so excessively enthusiastic about giving out those loans? They must have known that a sudden large devaluing of local currencies would cause a huge wave of defaults. Were they simply counting on the fact that, if push came to shove, their debtors would be bailed out by the IMF and/or the EU? Take, for example, Poland, Hungary, Romania and Latvia. Their total domestic credit is $258 billion, $89 billion, $73 billion, and $29 billion, respectively; and the share of foreign currency loans in that is 35%, 63%, 60% and 90%. So the total amount of foreign currency loans is about $220 billion (and that's rounding way up, too). So assuming all those credit markets crash all at once with a catastrophic default rate of 10%, we'd see a hole of about $22 billion. That's not a lot of money, and it's a fair assumption to expect the IMF or ECB to step in and cover that.

Still, some of the banks operating in those countries have denominated close to 100% of their loans in non-local currencies. I don't really know much about finance; but does this sound like good risk management?

Stunning links

What happens when human crowd goes on a stampede.

What exactly does "brilliant legal mind" mean?

A sane court ruling on drug use.

Let's tax the sh*t out of technological progress; after all, it puts people out of work.

Economist talks about the Polish government's long-term financial strategy (in Polish).

An imperfect argument

What would political debate (or, for that matter, any debate) look like if its participants truly internalized the fact that arguing to the effect of "You are accruing personal gains from publicizing your arguments, therefore your arguments are wrong," is a fallacy?

A perfect world

Mathematicians have axiomatized the real line as a one-dimensional continuum, as a complete ordered Archimedean field, as a real closed field, or as a system of binary decimals on which arithmetical operations are performed in a certain way. Each of these axiomatizations is tacitly understood (...) as an axiomatization of the same real line.

***

(...) there is no way of dealing with mathematical items rigorously except through axiom systems. But this is like saying that there is no way of communicating ideas except through words. Although any idea has to be represented in sentences, the same idea may be expressed by completely different sentences. An idea is "independent" (...) of the words used to express the idea. When we assert that a mathematical item is "independent" of any particular axiom system, we mean this "independence" in much the same way as independence of ideas from language.

Gian-Carlo Rota, Indiscrete Thoughts.

Live long only if your brain is young

After reading Eric falkenstein's post "Why I Don't Want to Live Forever" I realized I need to put a few caveats before what I wrote about life extension, because my own enthusiasm for it rests on a few assumptions that I admittedly haven't bothered to spell out.

First off, note that Falkenstein's essay is titled "Why I Don't Want to Live Forever," not "Why I Think No One Should Want to Live Forever." And even though he argues beyond what's in the title--i.e. he argues that if people could live forever it would lead to negative externalities--it's good to see someone arguing against life extension without trying to tell people they don't really know what they want.

His main points are two. First, human mind deteriorates with age. I completely agree with him that life extension that would "freeze" people whose brains are, say, 96-years-old for a long time would be a disaster both for the person interested and for almost everyone around them. Life extension would only make sense if we could figure out the way to slow down the ageing of the brain so that it would match the new extended lifespan. His second point is this:

I see so many people develop a personality that after a while converges on some big idea, some routine in thought and behavior, it becomes not merely unhelpful to the world, but boring for the person and every thinking person around him.

It's true, this does happen all the time. But, not being able to observe people who live for hundreds of years, we don't know if this happens because of some physical constraints on the brain, or because it's an optimal response of the mind to the fact that life is short. That is, do personalities really "converge" or do people end up specializing in one single thing simply because they know they don't have time to reinvent themselves? Say you're a mathematician and that when you're 30, you get this great, career-making, Fields medal-worthy idea. For the next forty years, you harp on this idea, fleshing out its every possible detail and application. This happens a lot--but does it really happen because your personality has converged on the idea, or because you know your life is too short for you to become equally good at something else than that idea of yours? What if we could live for a thousand years and be able to say "okay, I've become so good at mathematics that it's become completely boring to me and everyone around me. I think I'll try photography now"--and then go and become a great photographer? Wouldn't such life be desirable?

Why would anyone want to be the Prime Minister of Poland?

Seriously, I have no idea. You'd be putting yourself in a lose-lose situation.

Polish economy is on an unsustainable path. The biggest problem we face, in a nutshell, is that currently, for each employed person receiving income and paying taxes, there are on average two people who are unemployed and who receive public assistance from the government (retirement, unemployment benefits, health insurance, disability, whatever). This is unsustainable as it is, but it's getting even worse; due to catastrophically low fertility rate (1.29 live births per woman) and negative net migration rate, the population is shrinking and ageing. So the ratio of one person working supporting two people receiving government assistance is deteriorating further. A recent report from a National Center for Policy Analysis has estimated that if current trends facing Poland (e.g. demographics, GDP growth, structure of government receipts and spending, etc.) stay as they are now, then in the year 2050 the value of unfunded liabilities of the Polish government will be fifteen times the level of Poland's GDP. Something like this is really impossible; what the report actually says is that, if things stay the way they are, Polish government will be bankrupt much sooner than 2050.

If you're a Prime Minister and your government is forced to default on its obligations, that makes you very unpopular. Presumably, then, you should try to do something to prevent the doom from happening. The problem is that the things that all economists agree are necessary conditions of preventing the worst-case scenario, are all things that are extremely unpopular in the eyes of pretty much every single Polish voter. Everyone serious knows that if bankruptcy is to be prevented, all of the following changes must be made at one time or another:

1. Increasing the minimum retirement age. Currently it's 60 for women and 65 for men; at the very least, it would need to be set at 65 for everyone, but even that would probably not be enough. It looks like we'll need 70 for everyone.
2. Cutting spending on disability assistance. As of now, more than 13% of people between 20 and 64 are on some kind of disability. That's about three times as much as an OECD average.
3. Discouraging people from working in agriculture and/or changing special rules by which agriculture operates in Poland. Polish agriculture is extremely inefficient; it employs 17.4% of labor force, but produces only 4.6% of GDP--despite the fact that agricultural production is heavily subsidized by the government. It is an enormous burden on the economy, and on the budget as well (farmers don't have to pay income taxes; they also have their own state-owned social insurance agency to which they pay premiums in exchange for social assistance. The problem is that the premiums farmers pay cover about 8% of the assistance they receive).
4. Doing away with all or at least most early retirement privileges for certain groups (such as the military, police, firemen, teachers, judges, public attorneys and prosecutors etc.) They are of course well-deserved, but prohibitively costly.

Now keep in mind that these are just necessary conditions of avoiding a complete disaster; they are by no means sufficient. As of now, even hinting that you might want to try to actually do any item from this list may spell the end of your career as a first-tier politician.

Damned if you do, damned if you don't. Why, then, are there still people who actually want to govern Poland? The most competitive electable office in Poland should be that of the leader of the second-largest opposition party. (Why second-largest? Because if you're leading the largest opposition party, you're running a considerable risk of actually becoming Prime Minister yourself.)

10^(10^100) nerdy math hints

While watching an episode of The Simpsons, I've noticed that one of the local movie theaters in Springfield is called Googolplex Cinemas.

It turns out the whole show is chock-full of math references.

Stunning links

Who do you feel superior to?

Macroeconomics is complicated and bewildering.

Actually, macroeconomics is straight crackpottery. (Me, I'm leaning towards the stronger judgment. Maybe it's on a path to evolve into something useful though.)

The Pittsburgh diocese cuts off payments towards the mental health treatment of the victim of sexual abuse by one of its priests, while continuing to pay the salary and health insurance to the priest convicted of the abuse. It gets worse: The victim committed suicide.

Insufficient success measure

President Obama announced recently that GM and Chrysler bailouts were a success; most of the media agreed. The reason is that, since receiving government money, both companies started turning up profits, for the first time in a long, long time.

But is this enough to be so confident that the bailout worked? After all, it shouldn't be very surprising that if a business that's in bad debt trouble all of a sudden gets outside help with their debt, it can become profitable. Opponents of the auto bailout (the intelligent ones, at least) never said that the bailout was a bad idea because the automakers were inherently unprofitable. They said it was a bad idea because it wasn't worth the cost. Costs of the bailout are of two sorts: opportunity costs (distorting allocation of resources) and moral hazard (sending a signal to the economy that if you're "too big" or "too important" to fail, you can get away with more because if you end up getting yourself in trouble, you will be bailed out). No one knows how large these costs are. But unless you somehow estimate them, you can't claim that the bailout worked. Anther issue is, it's only been a year and a half since the government injected cash into GM and Chrysler. Who's to say that their newly found profitability will last any significant amount of time? What's the guarantee that, in say five years, another bailout won't be needed?

Of course it's better to show profits than not. But that's about the only conclusion that can be drawn right now.

Admit it: you're just jealous

Suppose that sometime in the near future, a medical treatment becomes available that can extend human lifespan to about a thousand years. Suppose also that you can afford the treatment. Would you do it?

I know I would. There are so many things in life I would want to do but know I won't have enough time to do. I once calculated that, assuming a reasonable reading pace, just reading all the books I would want to read would take me about 200 years. And that's just books; there's much more to life than books. Life is tragically short and I would take a chance of extending it in a heartbeat.

I know that there are some people who wouldn't take that chance. I don't understand them, but I know that preferences vary, and that there isn't much point to trying to change someone's mind about their preferences. It's all the more surprising to me that there are ethicists, philosophers, and other sorts of writers out there who are trying to convince people who think life extension is a good idea that in fact it is not. They say that the length of human life as it is now is about optimal and that, were it much longer, people would inevitably get bored with their lives and become utterly miserable.

It seems utterly bizarre to me that anyone thinks this is actually a cause for concern. No one is seriously thinking that, if such hypothetical treatment became available, anyone should be forced to take it against their will. If you think long life would make you miserable, don't take the treatment. But since I don't think long life would make me unhappy, let me take it. And even if you're right and, 500 years after making my choice I come to deeply regret it, then I've ruined my life, no one else's. I've made myself miserable; what's it to you?

Prepare now for some armchair psychologizing. I think that arguments of this sort are, for some people, a defense mechanism against strong feelings of envy. Imagine a recovering alcoholic. He loves drinking. But he can't, because he's discovered that he is completely unable to drink in moderation and that, had he continued drinking at his normal pace, it would completely ruin his life, possibly even kill him. So he stays sober. Every day, though, he sees people who enjoy drinking and drink whenever they want, but are not addicted, and are able to "enjoy drinking responsibly," as booze commercials put it. He envies those people deeply; after all, they have something he wants but knows he can't have. The very fact that he meets those people on a daily basis brings him considerable distress. What can be done about this distress? He can try and convince himself (and possibly others) that moderate drinking isn't really possible. He'll say that alcohol is uniformely bad for everyone, and those who think they can control their drinking are deluding themselves. Or perhaps he'll exaggerate health risks associated with moderate drinking. Or maybe, if prohibition is politically viable, he'll passionately argue for that alternative, as it would remove situations that trigger his envy from his sight once and for all.

Or imagine someone who very strictly adheres to Catholic moral code with respect to sex. No sexual relations outside marriage, no divorce, and no contraception ever, under any circumstances. Let's say that, on some level, he believes that "no strings attached" sex with various partners is actually a lot of fun. Every day he sees people who live his secret dream and who seem to lead happy, accomplished and wholesome lives, and he is jealous of them. What can he do to reduce his distress? He could try to tell himself and others that, while a life of uncommitted sexual encounteres may feel pleasant, it is actually not; there's some kind of a price to be paid for living this lifestyle. (Think about those who argue, contrary to most evidence, that oral contraception is incredibly dangerous to one's health, or those who exaggerate the risks of being infected with an STD.) Or, just like the alcoholic from the previous example, he may argue for a prohibition of sorts. Right after the pill was invented, the political movement aimed at making it illegal was quite strong. Today, this attitude can be seen in some of the people who argue that HPV vaccines should not be available on request.

I think that the same psychological mechanism is at work in at least some people who argue that no one should want life extension because it would be bad for everyone. They are those who are morally opposed to extending human life but who, deep down inside, suspect that living a very long life might actually be fun.

A quote

The same possibilities of thought are open to everyone, so that we can take the world of possible forms as objective and absolute. Possibility is observer-independent and therefore real, because it is not subject to our will.

Kurt Gödel, quoted by Rudy Rucker in Infinity and the Mind.