I've often been asked what's the best way to lose 10 lbs quickly, usually by someone who is getting ready for some major event. A few times, I've answI've often been asked what's the best way to lose 10 lbs quickly, usually by someone who is getting ready for some major event. A few times, I've answered: "You could cut off one of your legs." For some reason, this answer never goes over that well. And yes, its not as funny as I first thought, but it does have a point.
Of course, most people mean they want to lose some subcutaneous fat. That is why most people ridicule the early weight loss on a low carb diet: it's only water that you lost, so it doesn't mean anything. Similarly, everyone gets reassured if they gain some weight when starting an exercise program: muscle is denser than fat and it raises your metabolism. That's a good weight gain.
But there are people who want to lose weight for other reasons. I recently went back on a low carb diet, partially to lose some fat. But my immediate goal was to get some pressure off of my aching knees, and maybe to lower my blood pressure. The diuretic effect of the diet did both of those things very nicely. And going back on the low carb diet also led me to this book.
Taubes is great at challenging conventional wisdom. This book divides basically into two parts. Part one criticizes the idea that dietary fat causes heart disease. Part two challenges the idea that overeating and lack of exercise cause obesity. The amazing thing is that on both fronts, Taube is very convincing.
The first part is the easier one to swallow, and I think its the more important point. Taubes does a great job of showing the growth of misinformation about dietary fat, cholesterol, and heart disease. He does an even better job of showing how things can go astray when science and public policy get intertwined. He also gives a decent alternative hypothesis for the causes of "diseases of civilization," which include obesity, heart disease, diabetes, hypertension, etc... These diseases tend to appear in populations along with the increased consumption of refined starches and sugars. Taubes argues that high carbohydrates may be the culprit, and not high fat. The key evidence for me personally is the relationships between carbs and triglycerides and HDL. A low carb diet tends to raise HDL, and will almost immediately bring triglycerides into line.
The second part is a bit tougher going. The typical thinking about obesity is as follows: it's governed by the conservation of energy. Consume more calories than you burn and you gain weight. I've had my own reservations about this simple idea for a long time. First off, energy has no mass. Thus, this reasoning is at best derivative. Weight gain or loss is a question of the conservation of matter not energy. Mass only gets turned into energy in atomic reactions, and I don't think I have all that many nuclear explosions going on in my body. That's not a promising road for weight loss.
Thinking about it as mass, how does a body gain weight? Eating, drinking, and inhaling. How does it lose weight? Shitting, pissing, sweating, shedding, and exhaling. The surprising thing, I think, is that most of our actual weight loss comes from the difference between inhaling and exhaling. We inhale O2, and exhale C02 which is almost twice as heavy as the inhaled molecules. The CO2 is basically our way of getting rid of the ash that's left when we burn our fuel. But this is just my aside, and one that points out the significant jumps that are made by the calorie in, calorie out idea.
Taubes criticism is quite different. He basically says that the calorie in, calorie idea is correct, but that it says nothing about the cause of obesity. Suppose you saw a club that was really crowded and you wanted to know why. You could ask someone like me, and I might tell you that its because more people came into the club than left it. Well, duh. But you wanted to know why the club was crowded. Taubes says its the same thing with obesity. The trouble with staying with the calorie in/calorie out idea is that it says nothing about the cause. People then fall back and say the cause is a lack of willpower. (How would a determinist respond to this one, I wonder?)
Taubes instead says that both obesity, and the caloric imbalance, are symptoms of something else. His hypothesis is basically that the obese suffer from a type of insulin resistance. Their muscles are insulin resistant while their fat cells remain sensitive to insulin. This causes their fat cells draw fat and energy out of the body. The muscles sufficient energy because the fat cells have hogged it up. This leads to a state of semi-starvation as far as the muscles are concerned. Metabolic rate drops and the person conserves energy by moving less.
We can cut insulin by cutting carbs, so cutting carbs should bring an obese person back to health. It's a nice theory. Unfortunately, the dispute is now more political than scientific. The establishment simply wants to show that low carb diets are bad for you, or that they are just reduced calorie diets in disguise. So they have no interest in genuinely testing the ideas. The low carb community tends to create zealots of their own, with as little interest in the science as the establishment. So it doesn't seem likely that anyone will do controlled tests on these hypotheses.
I find the whole thing to be fascinating. I've read that Taubes has succumbed to some of the biases that he criticizes -- mainly that he has ignored some studies that might be uncomfortable to his ideas. Getting to the bottom of that would require more effort than I'm willing to put in. In part, I like this book because I always like a book that convincingly stands the conventional wisdom on its head. I also think he writes amazingly well, especially for a book this heavy on science. And I think the ideas are worth considering, especially the idea that our received "wisdom" about dietary fat may be all wrong.
I first heard about the efficient market theory in Law School. I remember thinking at the time what obvious bullshit it was. But it was academia, andI first heard about the efficient market theory in Law School. I remember thinking at the time what obvious bullshit it was. But it was academia, and it was pretty harmless bullshit, so let the economists play whatever games they want. What difference did it make?
The theory goes that the markets already consolidate all the information available to them, so that price already incorporates all the information available to the market. From there, we get the random walk theory -- that prices will move in a random fashion, so that each price move is basically the flip of a coin. And from these premises, we then get modern financial theory, including the idea that risk is the same as statistical variance, which leads to the Sharpe ratio for evaluating an assets value, and also leads to the Black Scholes method for pricing options, and to modern portfolio theory (by which a portfolio is designed around the appropriate level of risk for an individual investor). The math for doing this seems very sophisticated, and variations on these approaches have served as the backbone for the financial industry.
But there's a slight problem. The basic assumptions underlying all this theory is wrong. Prices don't vary like the flips of a coin. They are much wilder that tossing a coin. According to conventional theory, Black Monday in 1987 should have occurred perhaps once in an eon. In 1997, there were three days in a short period of time that had moves which the theory would predict should occur only once every 10,000 years or so. And the same thing again for the recent financial collapse.
Wall Street adopted these economic theories. They were relatively easy to use. They have an air of scientific knowledge to them. There are nobel prizes awarded to the developers of them. But, they don't fit the data at all. They grossly underestimate risk, largely because they insist that data should fit a bell curve, when it simply doesn't fit. And they then took risks, this time with their own money, based on these false economic engineering ideas. The result was the near collapse (and the jury may still be out on this) of the entire world financial system.
Mandelbrot, the author of this book, is a mathematician. He invented the field of fractal geometry, and is probably most notable for the Mandelbrot set, which yields incredibly intricate and beautiful fractal designs. As far back as the early 1960s, Mandelbrot did extensive study on Cotton markets. For some reason, there is good data on daily cotton prices going back to the mid 1800s. As a result of his studies, Mandelbrot concluded that markets are more fractal than continuous, and that the assumptions that economists used were simply wrong. He started complaining about this 40 years ago, and as recent history shows, people still are not listening. He claims to have written this book to bring his case directly to the public. (The same process worked pretty well for him in popularizing the idea of fractals in the first place, and ultimately getting them accepted in academia, where math departments were skeptical of geometry with practical application.)
The book is very well written, and easy to understand, especially since it deals with a field where people tend to be abstruse and to obfuscate whenever possible. (Have you ever read any statement by Alan Greenspan, for example?) The criticisms of standard financial theory seem perfectly sound.
However, when it comes to giving practical advice, the book seems on much shakier grounds. He calls for more open minded study of markets, which would not be a bad thing, especially since we now know that the market making companies are all too big to fail. On the last page, he calls for a "coordinated search for patterns in the financial markets." And this is fine. But at several places he makes fun of "chartists, " precisely because chartists think that they have found discernible patterns in the markets. He doesn't offer any evidence to show that they cannot have done so, and his call at the end shows that he thinks there may be such patterns.
Overall, I think this book is worth reading for anyone who is interested in the behavior of markets. And its fun for people, like me, who are deeply skeptical of the usefulness of anything that comes out of an economist's mouth....more
I picked this up because I'm interested in studying markets and technical analysis. The Black Swan talks a bit about fractals and the Mandelbrot set.I picked this up because I'm interested in studying markets and technical analysis. The Black Swan talks a bit about fractals and the Mandelbrot set. One of the interesting thing about some fractals is that the part resembles the whole. In technical analysis, there are several techniques that apply to charts, and the period of the chart doesn't matter. The same sorts of things work on weekly, daily and hourly charts, etc.... Another part of technical analysis is Elliot Wave theory. Without getting into the details, the proponents of this theory also claim that there are smaller Elliot Waves within a larger Elliot Wave. Both of these observations seem to show that, in market patterns, the smaller part resembles the larger.
So I went looking for a good book on Fractals. Barnes and Noble didn't have anything by Mandelbrot (he's next for me), so I decided to learn something about Chaos, which is related. I'm glad I did.
This book provides a good, and readable, overview of the field. There may be a bit too much about sleds going down mogul fields. But, then again, its a pretty great example for proving the point. For a long time, I've believed that if someone invents the Math, someone else will find a real world application for it. I think Chaos theory might be another example of this phenomenon at work. Unfortunately, it's been a long long time since I've worked with differential equations, and I think I may have to settle for the lay understanding of this sort of field. With the math background that I do have, and the time I've spent away from doing real math, I thought this book was pretty perfectly pitched for me....more
This is a fifteen year old essay on operating systems that is still interesting, in a few ways. It has some nice ideas about operating systems and infThis is a fifteen year old essay on operating systems that is still interesting, in a few ways. It has some nice ideas about operating systems and information systems in general. Because it's by Stephenson, it's fun, well presented, geeky but well written. And, because it's by Stephenson, it casts some light on things that appear in his (better) novels.
He contrasts four operating systems: OSX, Windows, Linux, and BeOS. Of these, he hates the first two, primarily because the GUI takes away the command line interface and makes them too cumbersome to hack elegantly. He loves Linux but recognizes that it's a steep learning curve, and admits that a GUI, while just a metaphor, is a useful metaphor for most people. His pick of the litter is BeOS.
Funny then that the BeOS company went out of business and sold to Palm (for just 11 million) only two years later. Palm then caused it's Be subsidiary to sue Microsoft for having tortuously interfered with its business relationships, and Microsoft ultimately settled the suit for 23 million, without admitting liability. So it looks like Stephenson might have been right about BeOS, but that MS, in the endless spirit of "innovation" that it's supporters always talk about, killed the company because they couldn't beat it on technology.
He does a great job explaining the implications of having a business selling operating systems. One implication is that the business itself is doomed because operating systems are both free and commonly known, at least to hackers. This caused the symptom of feature creep, in the hope of creating an illusion of value in something that should be free. He thus predicted the downfall of the OS business as king, without claiming to know what development would knock MS from the throne. Turns out it was Google, on the one hand, and the advent of smart phones on the other.
There's also a delightful explanation of the Microsoft help system, and the irony of making customers pay, $95 per incident, to help debug Microsoft's own product. This business model was designed to hide how buggy the product was, and to delude people into thinking that the information they got from MS was valuable. In the hacker world of Linux, help was available readily and for free, but assumed a certain amount of technical competence. The further point, that Stephenson did not make, is that most of the businesses that flocked to Microsoft we're already hiring computer experts to handle their systems, and those people could have managed Linux better. So why did MS prevail so long?
Stephenson calls it "mindshare". The only monopoly that MS seemed to have was in the collective minds of people who didn't know any better. That sort of monopoly is the most fragile of all. It's the same thing that turns a pop singer into a cultural phenom one week, and makes her a has been in less than a year.
Finally, not content to simply talk about actual Operating systems, the essay closes with a neat comparison of computing outputs to the multiverse. Imagine there's some sort of computer that creates universes. A programmer puts in the various physical constants on something like a command line: grav-9.88; port size-1.02;etc... As he puts it, this makes for a lot of dud universes in your basement, but a handful of structured ones, and a few that have life or even intelligence. So, from OS wars to philosophy, and all with a sense of humor. That's Stephenson for you....more
Gladwell's basic argument is that people can't pull themselves up by their own bootstraps, and that everyone who is successful had some help, and someGladwell's basic argument is that people can't pull themselves up by their own bootstraps, and that everyone who is successful had some help, and some luck, along the way. Despite Rush Limbaugh's outrage earlier this year when Obama said pretty much the same thing, I don't think that this is a very challenging or distrubing idea. If that was all there was to it, I wouldn't have liked this book at all. But I did like it, mostly because I found quite a bit of fun in the details.
What goes into success? First a person is given both a chance and an advantage. Gladwell points to selection bias when we choose kids for advancement amongst those in their age group. This almost always tends to give an advantage to the oldest children within the age group, because the selection process tends to confound maturity with talent.
Seventy percent of Canadian professional hockey players are born in the first half of the year. Why? Because when the kids are young, the best kids born in a year are selected for a better league, with more practice time and better coaching. So they start off better because they are older, but quickly become much better because they are given time, attention and praise. The same results apply almost everywhere, and the effects can be seen in things like who goes to college, to even who is more likely to commit suicide. All of this because of some arbitrary line that we draw about age.
This is a very interesting idea, but the basic idea behind it is quite simple and old. It's essentially a variation of Virginia Woolf's idea about Shakespeare's sister - equally talented as the bard, but never given a chance because of a basically irrelevant distinction.
Next point is that it takes 10,000 hours to become an expert at anything. This is both an extremely powerful rule of thumb, and just plain wrong. Let's start with why its wrong. How long does it take to become an expert at slot machines? There's no answer because there's no such thing. Now how about tic-tac-toe. I haven't played for 10,000 hours, but I can pretty much guarantee that I will bring anyone to at least a tie in that game, no matter how much more experience they have. Some things defy expertise, and some other things are easy to master.
But even in the middle ground, I don't think it's so obvious. Until very recently, the longbow was a superior weapon to a rifle/musket in almost every respect. It had a longer range, a better ability to pierce armor, a superior rate of fire. It was cheaper to construct and maintain. But it had a crippling disadvantage. It did actually take 10,000 hours to master the longbow. It took strength, co-ordination, and lots of practice. By contrast, it was possible to train infantry to shoot a rifle in a very short period of time. Thus, the rifle became the weapon of choice for armies because it was easier to master, not because it was better in other ways.
The rule of thumb is powerful, however, because it gives an idea of how much practice and commitment is likely to be involved in learning any fulfilling job or hobby. The examples Gladwell gives are classical musician, composer, chess master, and then he asserts that each of his other success stories have also put in their 10,000. There are two caveats here. Even if it might take 10,000 hours to get good at something, that doesn't mean that putting in the hours means that you will get good. I was probably well on my way to my 10,000 in basketball by the time I graduated high school, and I was never going to be any better than an OK high school player. Other factors were involved (I was slow, but I couldn't jump.)
The other thing, and its one that Gladwell doesn't mention. My acting teacher used to define talent as "the ability to become involved." In this context, what that means is that if you can devote 10,000 hours of practice and serious concentration to something, that fact alone shows a level of passion and commitment that other people lack. Gladwell makes quite a bit out of Bill Gate's extraordinary opportunities to be around computers before they were widely available. He doesn't make anywhere near as much of what Gates called his "addiction" to that computer time.
The next element of success is a certain threshold level of ability. Here, Gladwell focuses on IQ, and makes the point that after a certain threshold, IQ tests predict nothing about a person's success. People with the highest IQs are no more likely to win Nobel prizes than others with a fairly high IQ. The same thing goes for SAT and law school entrance scores. Thus, for example, law school affirmative action students get lower scores on the LSAT, and tend to get slightly worse grades in school, but they do just as well as their contemporaries after they get out of school.
Sprinkle on top of this a whole lot of luck, or fortuitous timing. The example that Gladwell uses is that about 15 of the 100 richest people in history were all born in the 1830s in the United States. Similarly, the most successful New York Jewish lawyers all tended to be born in the early 1930s. And if you wanted to get really rich in Silicon Valley, you probably needed to be born about 1955. He gives some pretty good arguments for why these things happened, but he also appears here, as well as with some of his other examples, to be cherry-picking the absolute best fits.
I'd like to see what Gladwell has to make of the following: Mozart, Beethoven, Haydn, and Schubert were all from a very narrow geographical area, all Austrians, four of the greatest composers of all time. They all lived at very nearly the same time in Vienna. How does something like that happen? Out of all of history, how does so much greatness concentrate itself in both such a narrow area and timeframe? Another similar example: Jerome Kern, Irving Berlin, George Gershwin, Richard Rodgers are four of the towering giants of American songwriting: all of them are from New York City, born within 17 years of each other, and they were all Jewish. Again, how does something like this happen?
This leads us to Gladwell's last point: cultural background matters. Gladwell tells a fascinating story of how Korean Air Lines had a rash of crashes. Basically, the reason for the crashes came because the flight crew were uniformly too deferential to the Captain. Planes are safer when an underling can say something like "There's a mountain right in front of us." or "We're running dangerously low on fuel and need to land now." But my guess is that there are strong cultural reasons that would explain the Vienna musicians, and the New York songwriters. I just don't know what they are.
Gladwell also tries to connect the idea that Asian's being good at math with their rice farming. Apparently rice farming takes both a lot of work compared to other farming, and it also takes more thought and planning. This leads to a culture that strongly endorses the work ethic, which in turn leads to better math students. He also claims that these cultures have an advantage because their language more directly models the form of numbers than English and western languages. For example, where we say eleven, the Chinese say ten-one. And twenty-one is two-ten-one.
There may be a point here, but I think its a shallow one. This is supposed to be a book about outliers and success stories. Here is an internet ranking of the greatest mathematicians of all time:
Five of the hundred are from China or Japan. None from the other rice growing areas of the world. This is nothing in comparison to the number of French and Germans on the list. Math isn't the kind of field where there would be a strong cultural bias. If the Chinese had been making great discoveries in math, there's no reason to think they wouldn't get credit for it. So, even though Gladwell might have explained why Asian kids get better scores on standardized math tests, that has little to do with the subject he actually said he was going to talk about. The greater question, for me at least, is if Asians are so good at math, why has there been so little development of mathematical knowledge coming out of Asia. In other words, if they are so good at math, why aren't they better mathematicians?
I liked this book. I thought it was well written and fun to read. The examples were interesting, but too obviously cherry picked. Much of what's said here is driven home better in Taleb's Fooled by Randomness. But there were some surprising examples and studies that I had not heard before, and Gladwell has a style that makes things both simple and engaging. I would have liked it better if the central idea were a bit more startling, so as it is, it left me feeling that it's just a little slight....more