Tuesday, December 15, 2009
Wednesday, December 09, 2009
So the conversation was about a simple demography puzzle, and my boss had offered a chocolate bar to whoever solved it first.
The problem is this: 100% of a population were alive at the beginning of a year. 60% were alive at the end of the year. Assuming that the mortality rate is constant throughout the year, what percentage of individuals were alive at the exact middle of the year?
Note that a constant mortality rate does not mean that the same absolute number of individuals die each day, but rather than the same proportion of those starting the day alive end the day dead.
Motivated by chocolate, and using one simple bit of algebra, I secured the Intense Orange Lindt dark chocolate bar.
So I can’t hang a chocolate bar in the comments section, but I can promise kudos if you can tell me what portion of individuals were alive after six months, and how you got that answer.
So far I can't find any evidence that anyone has a method for this.
Tuesday, December 08, 2009
It is very hard to get any science done while I am sick. Partly there is the general lack of energy, lack of focus and slow mental activity. But I also make the weirdest mistakes while I am sick. I send people emails with the same sentence three times in a row phrased slightly differently each time, without realizing I am repeating myself. I decide that I have accidentally deleted all my emails when in fact I am just looking at the wrong mailbox. I write a thought that pertains to one paper into a different paper, then have trouble figuring out which paper it is.
I understand that my body is scaling back on certain activities (such as cognition) so as to be able to go all out on others (immune response), but honestly given the quantity of lipids I am carrying around I would think a little bit of multitasking could be supported.
Sunday, December 06, 2009
I've recently written about the importance of having names for common logical fallacies, and this got me wondering what the name for this guy's fallacy is. It is an extremely common one, and is in no way original to him. The fallacy is this: assuming or implying that if one side in a debate/argument/conflict is wrong/guilty the other side is therefore right/justified. This most often comes up in moral contexts, where the misdeeds of one party are used as a defense for the misdeed of the other party, but is also used in the context of disagreements about fact. For example when it comes out that an evolutionary biologists was wrong about anything, creationist make the leap to this being proof of Creation, rather than simply a flaw in the thinking of a biologist. One side is wrong, so the other must be right, even if the flaw is immaterial to the disagreement. Similarly, it is common in interpersonal disagreements to hear one party respond to an accusation of misbehavior only by pointing out a misbehavior of the other party without ever replying to the statement about their own behavior. This often goes well beyond "two wrongs make a right" to "my behavior is necessarily right because yours is wrong." This is also distinct (and almost opposite) from the idea of moral equivalence. In the Arab-Israeli conflict, for example, some people argue that the crimes committed by supporters of the two sides are morally equivalent, and therefore neither side can be held responsible. Each side often responds to this nonsense with the counterfallacy that our behavior, whatever it may be, is justified by their crimes. They are criminals therefore we are just. I would tend to assume that each party or individual is responsible for its own actions, and whether or not the crimes are equivalent is morally irrelevant.
So this raises three sets of questions for me:
1. What is this fallacy called? If we want to describe a response as following this pattern, how should we refer to the pattern?
2. Why do humans do this so freely? On some deep level are we programmed by evolution to use this type of rationalization? Is this culture specific, or do all humans do this?
3. Why is this particular type of illogic useful/successful in arguments? Perhaps it is particularly effective because it allows one to move from being on the defensive to being on the offensive, to accuse rather than excuse (or to effectively do both at once)? Or maybe it is just very hard for people to find fault in both sides of a conflict at once, so by making them see the fault in the other side you make them forget about the fault in your own?
I'd appreciate hearing your thoughts on this, particularly what this type of fallacy should be called, or if it already has a name. I've checked Wikipedia's list of fallacies, and it ain't there.
Friday, December 04, 2009
Twenty or thirty of us came to watch. Now Demographers are a pretty staid crowd, but by ten minutes in people were chuckling, and within a half hour there was full-bellied, breathing-difficulty, rolled over in pain laughing going on. Clearly, people who actually think about demography were not the target audience.
These two documentaries, are based on the premise, which they take intensely seriously, that humanity (or at least the white section thereof) is at risk of economic ruin, political chaos, pain, suffering, homosexuality, the death of the traditional family and ultimate and total extinction because of a population control conspiracy by the UN, the EU, the Ford Foundation, Democrats, Liberals, Communists, UC Berkeley, Charles Darwin, Malthus, W.E.B DuBois, Gloria Steinem, Big Gay, Nazis, Feminazis, and most of all Paul Ehrlich. Dr. Erhlich, a professor at Stanford is a favorite punching bag of the right because he made many and varied dire predictions back in the sixties and seventies, and like most prolific prognosticators, many of his forecasts were wrong. His 1968 book, The Population Bomb, is identified as the driving source behind the idea that overpopulation might be a problem. In it he made various overly pessimistic predictions about the rate of population growth and the rate of food productivity growth, and concluded that we would see mass starvation of hundreds of millions of people by the 1970s or '80s. That this didn't happen is taken as proof that there are no possible ill effects of overpopulation, and that in fact humans are now heading toward population decline, which will by the end of the century see an under populated world dominated by geriatric patients, Muslims and Latinos. The same three or four animated graphics are shown incessantly, demonstrating that "westerners" (i.e., white people) are going extinct. "By the end of the century, there may not be any actual French people in France." They string together statements from representatives of various Teabagger interest groups and wildly out of context statements by academics (often repeating the same clip of the same academic to make it seem like they are agreeing with two very different ideas) with alternatively faux-reasonable and openly snarky narrators. The failure of the US auto industry, the housing bubble, immigration, homosexuality, terrorism, crime, feminism and the excesses of Wall Street are all shown to be symptoms of insufficiently rapid population growth. Demographers from all over the world hooted and guffawed and thought it was just the funniest damn thing they had seen.
Now like most vehemently presented lies, there is a grain of truth to the hysteria behind the movie. That grain is this: some, but not all, population forecasts predict that world population will cease growing some time around 2050, and may gradually decline for some decades thereafter, falling from maybe 9 billion to maybe 8.5 billion by 2100, and in the mean time the ratio of older people to younger people will temporarily increase. (Forecasts any further out than that are beyond the realm of speculation into pure fantasy, but one thing we can say with high confidence is that no population is likely to just stop breeding and go extinct.) This will pose some serious issues we need to think about over the next few decades. (I've written about this before, here.) Our markets, as currently structured, assume continuous population growth, and we don't yet have very clear ideas about how we need to adapt to population decline if it happens. Having lots of old people per working adult is a problem if you assume that it takes the same number of working adults to take care of each old person, and ignore that their will simultaneously be fewer children for those adults to take care of. The problem with the argument, even if you take out the hysteria, conspiracy theorizing, snarkiness, smear tactics and brain-washing techniques, is that overpopulation has known, current and disastrous consequences (see "Collapse" by Jared Diamond for several hundred pages on that, also a significant portion of the articles in Population and Development Review or Conservation Biology). I have never met a demographer who argues the problems of population decline are likely to be worse than those associated with population growth, or with trying to maintain a planet with more than 9,000,000,000 people on it. Second, I've never heard any demographer suggest that the cause of the eventual decline will be anything resulting from any policy of population control. Rather, educated, urban, mobile populations (and especially educated women) have fewer kids later in life, and that slows population growth. As the educational level and economic mobility of the world's women improves, and as people continue to move to cities, they will tend to reproduce less, no matter what the UN or Professor Ehrlich tells them. The clergy also have relatively little influence (see Italy).
But now that the lie is out there, no matter how laughable, it is a convenient tool for anyone who wants to argue against population control measures, family planning, contraception, feminism, etc. A friend pointed out to me a post on The Weekly Standard's blog stating that, "the discussion in demography circles isn't 'How do we cope with two extra China's?' Rather, it's "'How do we manage one of those extra China's disappearing?'" Living in a "demography circle," I can report that the Weekly Standard's unnamed source for that statement is a made-for-Fox-News propaganda special called "Demographic Winter" and its sequel (which borrows numerous lengthy sections from the first part) called "Demography Bomb." Type "population decline" into Google blog search and up come numerous posts on conservative blogs mumbling the same point.
So while my international colleagues were laughing their lungs out, I was exchanging dark glances with the only other American in the room. To those not familiar with the propaganda machine of the U.S. far right, the movie was pure, bizarre, hilarious fluff. Man-eating purple platypus stuff. One of my colleagues later asked me, "Republicans aren't idiots right? So they do not take that [compound expletive] seriously. Maybe a few nutballs? This is a joke?" But to me, it was clear this was yet one more battle being opened in the American right's war on science. As long as one is denying evolution, climate change and the moon landings, may as well claim that demographers don't see any possible drawbacks to overpopulation, and in fact that population collapse is just around the corner.
Expect to hear more of this particular lie in the years ahead. As the right touts the four biologists willing to deny the possibility of evolution, expect them to repeatedly trot out the few demographers willing to pretend that humanity's very existence is threatened by population control.
Wednesday, December 02, 2009
What I think is interesting about this is the extraordinarily high level of truthfulness we expect from our scientists these days. Journalists, politicians, doctors and lawyers are all expected to, in varying degrees, present pictures which are rosier, clearer, more advantageous or less illegal than the straight hard truth. A defense attorney is expected to find the most preferable interpretation of truth, rather than the straight up truth. Doctors need to make their patients feel comfortable and confident, even if that means overstating their confidence. No one is surprised when Republican appointed judges reach different decisions than Democratic appointed judges. Text-book writers are free to get as much wildly wrong as they want, usually for no apparent reason. Advertising is the art of misleading without directly lying in a provable way. But Phil Jones, the guy who fudged the graph, is resigning his appointment.
This is not to say that I think this level of expectation is a bad thing. Scientists don't have the excuses for bending the truth that lawyers or doctors or journalists have. We are supposed to fight desperately hard against our biases, against anything that prejudices our communications or thinking. Of course realistically many scientists fail to live up to this ideal, and there are (and should be) consequences when these failings are exposed. But one of the many things reactionary deniers of all sorts (moon landings, evolution, Holocaust, climate, HIV/AIDS, etc.) tend to refuse to see is that science also has powerful mechanisms for keeping any one person's malfeasance from making too much of a difference to our larger understanding. The more respected and influential a scientist is, the more people there are looking to poke holes in everything he does. The more enshrined an idea is, the more it benefits the career of a young researcher if she can point out a fatal flaw, an exception, a modification, even an unexplained corner. Every scientist that was ever great built his or her reputation and career by finding flaws, limitations or unanswered questions in the work of older, more established scholars. If I could produce convincing evidence that macroevolution doesn't happen, I would be the most successful scientist of the century (unfortunately for me, macroevolution happens, so producing that evidence is going to be hard). Under such a system, fakery may help get a single paper published, even help build a successful career, but it can't easily lead to a lasting consensus that is contrary to data that somebody else can go out and collect, because somebody is always trying to tear a hole in anything that could possibly be torn. The single best argument for anthropogenic climate change is that nobody has yet succeeded in blowing a hole in it.
"What's new?" she asked.
"I have discovered that it is possible to live forever," he said, with no hint of irony.
"Oh?," I said, taking another delicious bite of pasta and doing my best to maintain a neutral tone.
He went on to describe how he had noticed that under a set of mathematical assumptions about the pattern of human aging, if one plugs in the right values for various parameters, one can get the result that life expectancy approaches infinity. I'm not going to give away his secrets, or try to explain the bit of calculus he uses, but the whole proof fit on one page including only a handful of equations. There, in black and white was mathematical proof that one could live forever. Well sort of. The math was impeccable, at least I couldn't peck it. The question is how relevant was the mathematical model, and how meaningful were the limits he was taking?
Often when we use mathematical models of the world it is because we think they not only approximate the outcomes of the pattern, but actually describe something about the underlying process. An object fired up into the air will fall to earth in a parabola, a real, honest, no tricks involved parabola. The form arises just from the interplay of momentum and gravity, and the parabola arises, not as a fluke, but under a wide range of gravities and velocities. In other words, we think that sometimes the mathematical ideal is what the world is actually approximating. There is thinking that the mathematical forms my friend employs actually are the underlying form of human aging. They are our best guesses anyway. So maybe, just maybe, exploring the limits of that form tell us something about the limits of possibility when it comes to aging. Unfortunately, relationships that hold under a wide range of velocities often don't hold at the limits. Shoot the object at an improbably high velocity and it will escape Earth's gravity entirely, and likely end up orbiting the Sun, eventually making an ellipse. Shoot the object too slowly and forces such as viscosity, friction and wind become increasingly important, and the object will trace a good approximation of a line-segment to the ground. So while my friend's mathematical discovery is interesting and novel, I remain skeptical that he has found the possibility of immortality. Rather he has shown that if one makes extraordinary and unexpected assumptions, one can arrive at extraordinary and unexpected conclusions. Important, but hardly the key to eternal life.
Sorry to be such a downer.
Some people are born with an ability to voluntarily contract just these muscles called Voluntary Tubal Opening, similar to the ability of those who can wiggle their ears. Those who have this ability can hear "pop" or "click" sound in the middle ear when actuating these muscles, and are able to hold the muscle contraction (some refer to this as 'clicking your ears to equalize the pressure'). Doing so will make one's voice sound louder to oneself. This ability allows such people to voluntarily equalize pressures at will when making rapid ascents or descents, typically in aircraft flights or large elevation changes in either tall buildings or mountainous treks.I am one of these people, although clearing my ears without swallowing wasn't something I was aware I could do until I took SCUBA classes some years ago. When I do this it makes a click loud enough that my wife can hear it if she puts her head close to mine. Unfortunately this doesn't seem to help in clearing a lingering ear infection, as I can't currently get my left ear to click.
I had decided beforehand that whatever I wrote, I would keep the review anonymous. This means that the journal editors know who wrote it, but the authors do not. They give reviewers the option of signing their reviews, but I'm not sure why. The temptation of course is to sign the positive reviews only, but this is considered something akin to slimy. I prefer to be able to give my opinion without considering what the authors might think of me, or how they will review my papers in the future. Unlike online forums where people can be as abusive as they want because they are entirely anonymous, here the editors of the journal know who wrote what and can respond accordingly.
I'm happy to have been asked, by a well-respected journal, to be a reviewer. I've learned from the experience. Perhaps I should request that next time they send me a paper I'll like?