Month: September 2010

New Idea About Learning Chinese

Seth Roberts12 Comments

 I never considered taking a class to learn Chinese. Too boring, too time-consuming. I’ve tried hiring tutors and going through a textbook. Better but too close to taking a class. That didn’t last.

For maybe half a year I’ve used Anki (a flashcard program) to learn characters. This is better — at least it’s lasted half a year — but I don’t study it often enough.

A friend suggested labeling things in my apartment — put a card with the character for chair on a chair, for example. Another friend pointed out that there are children’s books with big characters (one per page). That suggested my latest idea: Put these pages on the walls of my apartment. So whenever I look at the wall it will be a kind of test. If I don’t remember the character, I can look on the underside of the card for the answer.

I’m excited about this: it might actually work, I now think. It doesn’t require being still, which I think reduces learning. It spaces learning (you learn in little bits throughout the day), which is surely better than massing it. It allows great amounts of repetition. And it takes advantage of natural curiosity (whenever I see Chinese — in a sign, for example — I wonder what it means) rather than requiring discipline. As far as I can tell it requires no discipline at all. If it doesn’t work I’ll learn something about education.

Malcolm Gladwell on Twitter

Seth Roberts6 Comments

In the latest New Yorker Malcolm Gladwell says Twitter and the like are less revolutionary than claimed.

A month ago a friend and I discussed Gladwell. The friend said that after Steven Pinker’s review of What the Dog Saw, he couldn’t look at Gladwell the same way.

I said that was a silly review. Sure, Gladwell has faults, but he also has strengths. He chooses interesting research to write about and writes about it in an accessible attractive way. An example is the Korean Airlines chapter in Outliers. It had little to do with the rest of the book but it was excellent journalism. Pinker barely mentioned these strengths but did point out spelling mistakes. It is silly to judge something by dwelling on what’s wrong with it. (Exhibit A: correlation does not equal causation.)

Gladwell’s latest piece is one of his best. It makes four points:

1. The strong-tie/weak-tie distinction in social networks. An old idea, but worth being reminded of.

2. Strong ties were behind the civil-rights lunch counter sit-ins. The movement they helped start was long and dangerous. Strong ties helped.

3. Twitter and other social media create weak ties. It isn’t clear they create strong ties. Donations based on weak ties were in several cases a few cents/person. Much less than the cost of participation in the civil-rights movement.

4. If you’re going to claim something is “revolutionary”, as Clay Shirky did about Twitter and the like, you should start your book with a better example than a rich guy getting his Sidekick back.

Perfectly good points, especially the last.

Tyler Cowen’s reaction.

The Nobel Prize: Not Helping

Seth Roberts14 Comments

Nassim Taleb recently criticized the Nobel Prize in Economics:

According to Taleb, there are a number of mistaken ideas about forecasting and measuring risk, which all contribute to events like the 2008 global crisis. The Nobel prize, he says, has given them a stamp of approval, allowing them to propagate.

It isn’t just economics. As I’ve said before, the Nobel Prize in medicine was not given for the discovery that smoking causes lung cancer. It was not given for the discovery that lack of folate causes birth defects. Both enormously useful. It has been given for several discoveries, such as the connection between teleomeres and aging, with (so far) little or no practical value.

This is no mystery. The Nobel Prize must be prestigious, therefore must honor high-prestige research. Veblen argued long ago that in academia high prestige correlates with low practical value. Just today I told a friend Veblen’s idea that professors use jargon for the same reason men wear ties — to show off how useless they are. The economics research (“Harry Markowitz, William Sharpe, Robert Merton, Myron Scholes, Robert Engle, Franco Modigliani and Merton Miller”) that Taleb is criticizing was high prestige. The so-far-useless biology that has received a Nobel Prize was high prestige; the highly-useful epidemiology that didn’t receive the prize was low prestige.

Thanks to Dave Lull.

The Stupidity of Crowds

Seth Roberts12 Comments

At Tsinghua I am teaching a class called Frontiers of Psychology. The students are reading The Man Who Would Be Queen by Michael Bailey. At one point Bailey mentions what is sometimes called the older brother effect: If a man has one older brother, he is more likely to be gay than if he has no older brothers, controlling for several things. This has been seen many times. In 1962 it was reported that gay men have more older siblings than other men but not until 1996 was it determined that this was due to more older brothers.

Bailey doesn’t mention the strength of the effect. The Wisdom of Crowds by James Surowiecki is about research that found that non-experts can do an excellent job of estimating this or that number (such as the weight of a particular cow) even when they know little about it. Their answers are excellent in the sense that the average of their answers is very accurate. Perhaps my students, who had read two-thirds of Bailey’s book, could accurately estimate the strength of the effect.

I posed the question like this. Suppose that when a man has no older brothers, his chance of being gay is 2.0%. What is his chance of being gay if he has one older brother? I gathered an estimate from every student. The median of their estimates was 8%. The correct answer is 2.7%.

The Corruption of Drug Trials

Seth Roberts2 Comments

In a clinical trial of a new antipsychotic drug done at the University of Minnesota, a man named Dan Weiss was given a choice: be hospitalized in a psych ward or, shockingly, “take part in an industry-funded study of antipsychotic drugs”. The usual choice is between hospitalization or conventional treatment. Weiss chose to be in the clinical trial. During the trial he killed himself.

An FDA investigator named Sharon Matson decided that Weiss had not been coerced into participating! During a trial, Moira Keane, the head of the University of Minnesota Institutional Review Board, which of course is meant to protect human subjects, claimed the purpose of the board was not to protect human subjects. The purpose of the board, Keane said, was “to make sure that Olson and the trial sponsor had a plan to protect subjects.” This is false. IRBs sometimes measure compliance, not just plans.

After Weiss’s mom sued the University of Minnesota and lost,

The university filed a legal action against Mary, demanding that she pay the university $57,000 to cover its legal expenses. Gale Pearson, one of Mary’s attorneys, says that while such suits are technically permissible, she had never seen one filed in her previous 14 years of legal practice. The university agreed to drop the lawsuit against Mary only when she agreed not to appeal the judge’s decision.

The article by Carl Elliott about this case also contains excellent discussion of how drug companies shape clinical trials to get the results they want — and when that fails, hide the results. The effect is that new drugs are approved that are worse than the drugs they replace.

Thanks to James Andrewartha.

Assorted Links

Seth Roberts4 Comments

Thanks to Dave Lull and Anne Weiss.

Why Psychologists Don’t Imitate Economists

Seth Roberts18 Comments

Justin Wolfers, an economist, via Marginal Revolution:

When I watch and speak with my friends in psychology, very little of their work is about analyzing observational data. It’s about experiments, real experiments, with very interesting interventions. So they have a different method of trying to isolate causation. I am certain that we have an enormous amount to learn from them. But I am curious why we have not been able to convince them of the importance of careful analysis of observational data.

By “careful analysis of observational data” I think Wolfers means the way economists search within observational data for comparisons in which the factor of interest is the only thing that changes (which is why he says “isolate” rather than “infer”). He’s right — it really is a methodological innovation that psychologists are unfamiliar with. It lies between ordinary survey data and experiments.

Here’s why I think this innovation has had (and will have) little effect on psychology:

1. Most psychology professors are bad at math. They still use SPSS! Which is terrible but they think R is too difficult. Economics papers are full of math. That is part of the problem. Math difficulty also means they have trouble with basic statistical ideas. When analyzing data, they’re afraid they’ll do the wrong thing. For example, most psychology professors don’t transform their data. It wasn’t in some crummy textbook so they are afraid of it. Lack of confidence about math makes them resistant to new methods of analysis. Experimental data is much easier to analyze than observational data. You don’t need to be good at math to do a good job. So they not only cling to SPSS, they cling to experimental data.

2. Psychology studies smaller entities than economics. Study of the parts often influences study of the whole; the influence rarely goes the other way. This is why, when it comes to theory, physics will always have a much bigger effect on chemistry than vice-versa, chemistry a much bigger effect on biology than vice-versa. Method is different than theory but if you aren’t reading the papers — and physicists don’t read a lot of chemistry — you won’t pick up the methods.

3. There is a long history of longitudinal research in psychology. Studying one or more groups of children year after year into adulthood. The Terman Genius project is the most famous example. I find these studies unimpressive. They haven’t found anything I would teach in an introductory psychology class. I think most psychologists would agree. This makes observational data less attractive by association.

4. Like everyone else, psychologists have been brainwashed with “correlation does not equal causation”. I have heard many psychology professors repeat this; I have never heard one say how misleading it is. To the extent they believe it, it pushes them away from observational data.

5. Psychologists rarely use observational data at all. To get them to appreciate sophisticated analysis of observational data is like getting someone who has never drunk any wine to appreciate the difference between a $20 wine and a $40 wine.

Shamelessness in Chinese Academia

Seth Roberts7 Comments

Professor Wang Hiu, a Tsinghua faculty member in the Chinese Language Department, was accused of plagiarism several months ago. You can read about it here. Professor Wang is no stranger to controversy:

Wang Hui was involved in controversy following the results of the Cheung Kong Dushu Prize in 2000. The prize was set up by Sir Li Ka-shing, which awards one million RMB in total to be shared by the winners. The 3 recipients of the prize in 2000 were Wang Hui, who served as the coordinator of the academic selection committee of the prize, Fei Xiaotong, the Honorary Chairman of the committee, and Qian Liqun, another committee member. Wang Hui was then the editor-in-chief of Dushu magazine, which was the administrative body of the prize.

He awarded the prize to himself! And his fellow committee members. Wang was editor in chief of Dushu for ten years. During that time, he published many hard-to-understand articles by his friends. The influence of the magazine shrank considerably.

Avocado Raises Blood Sugar

Seth Roberts17 Comments

Tim Lundeen writes:

We [Tim and his partner, Alexandra] first noticed that eating avocados raised our blood glucose when we were on a low-protein/low-fat/high-fruit nutrition plan. After 1/4 avocado each, we would both have fasting glucose of 95-99 instead of 80-85, with the effect lasting for about 4 days. It was quite repeatable, so we stopped eating avocados. We speculated at the time that it was due to the omega-6 content of the avocado fat.

We just tried avocado again with more typical nutrition, with about 25% protein, 25% fat, 50% carbohydrate with very low fructose, thinking that because we were eating more fat the effect might not be so pronounced, but saw the same elevated fasting blood glucose as before.

After some more research, we found out it is because avocados contain a sugar called mannoheptulose, which causes temporary dysregulation of blood sugar.

Mannoheptulose was first isolated in 1917. Mannoheptulose has been proven to be present in many foods, but is found most abundantly in the avocado (La Forge 1916-1917). In 1957, the first research was published in the Archives of Biochemistry and Biophysics (Volume 69, page 592), suggesting that avocado extract blocked normal insulin secretion. In 1963, it was demonstrated that avocado extract blocks glucose-stimulated release of insulin (Nature, Volume 197, page 1264). By 1967, low doses of avocado extract were found to inhibit both pancreatic secretion and synthesis of insulin without eliciting measurable hyperglycemia (high blood sugar) (Nature, Volume 214, page 276). This finding was significant because it demonstrated that a controlled dose of avocado extract could suppress pancreatic production of insulin without inducing a diabetic state. [https://www.health-marketplace.com/p-Obesity-3.htm]The problem with this is that your cells don’t absorb nutrition because insulin is reduced, so we have strong cravings for food, feel extra hungry all the time, and have been eating about 50% more calories to feel full. The net effect is not a good feeling…

This makes sense. And it is methodologically interesting. Spending zero research dollars, Tim and Alexandra learned something important about blood sugar control that the rest of the world seems not to know. (Except perhaps the researchers who did the avocado extract research.) None of the research articles they mention make clear the practical significance of the effect. To say that avocado extract does X doesn’t tell you how much avocado you need to get the effect.

When I google “avocado” and “blood sugar” (together), the first page of links all claim, at least at first glance, that avocado lowers blood sugar. But that’s just the internet. (Although Google is supposed to put the most reliable links at the top.) Then I went to the most authoritative possible source on what we should eat: the American Journal of Clinical Nutrition. I found only three articles that mention avocados in their title or abstract. None was about this effect. I also looked in Eat Drink and Be Healthy by Walter Willett and the Harvard School of Public Health. Nothing about this effect of avocado.