Seth Roberts

The journal Experimental Mathematics, started in 1992, publishes “formal results inspired by experimentation, conjectures suggested by experiments, descriptions of algorithms and software for mathematical exploration, [and] surveys of areas of mathematics from the experimental point of view.” The founder wanted to make clearer and give more credit to an important way that mathematicians come up with new ideas. As the journal’s statement of philosophy puts it, “Experiment has always been, and increasingly is, an important method of mathematical discovery.

Two papers in the latest issue of the American Journal of Clinical Nutrition provide more support for the idea that omega-3s improve brain function. The first was a cross-sectional study involving about 2000 persons 70-74 years old in Norway. Their fish consumption was measured and they took a battery of cognitive tests. The more fish you ate, the better your score on every test, even after adjustment for several things.

Here’s a nice essay about the Women’s Health Initiative, a nine-year mega-million-dollar experiment to measure the effect of “healthy eating” especially a low-fat diet.

The Flynn Effect is the steady improvement in IQ scores over the last 50 years or so in many places. It was documented by James Flynn, a professor of moral and political philosophy at the University of Otago. Flynn gave a talk at Berkeley recently. I asked him how the Flynn Effect came to be.

Of course. He didn't. And dozens of writers you have never heard of, much less read, much less quoted in everyday conversation, have. These wrongs are corrected in an alternative universe described here. The Biology/Medicine Prize has also been fairly ridiculous, although at least Robert Gallo hasn't gotten one:

Jane Jacobs tells a story about a handed-down meatloaf recipe: After the loaf is made, the end is cut off. “Why?” she asked. “We’ve always done it that way,” she was told. The original recipe was for a smaller oven, it turned out; the end was cut off to make the loaf fit in the oven.

In 2000, Hal Pashler and I published a paper called “How persuasive is a good fit? A comment on theory testing.” For more than 50 years, experimental psychologists have supported mathematical theories by showing that the equations of the theory could fit their data. We pointed out that this was a mistake because no account was taken of the flexibility of the theory. A too-flexible theory can fit anything. However obvious this may sound to outsiders, the practice we criticized was common (and continues).

In Sunday’s NY Times Magazine, Gary Taubes argued that epidemiology does not provide a good basis for health decisions — it is often wrong, he claimed. By “wrong” he meant experiments were more pessimistic. Things that seemed to help based on surveys turned out not to help, or help much less, when experiments were done. A 2001 BMJ editorial disagrees:

Because Gary Taubes is probably the country’s best health journalist, his article in today’s NY Times Magazine (”Do We Really Know What Makes Us Healthy?”) about the perils of epidemiology especially interested me. It’s the best article on the subject I’ve read. He does a good job explaining what’s called the healthy-user bias — people who take Medicine X tend to make other healthy choices as well. Does wine reduce heart attacks? Well, probably — but people who drink more wine also eat more fruits and vegetables.

An interesting Economist article about sex differences in a visual task calls an evolutionary explanation a “just-so story.” I don’t know if the late Stephen Jay Gould, evolutionary theorist, Harvard professor, and “one of the most influential and widely-read writers of popular science of his generation” (Wikipedia), invented this form of dismissal, but certainly he was fond of it. Here, for example:

A friend of mine has started to wonder how to find scientists he will feel comfortable working with. For the past year, he has been working in a lab in a very prestigious institution. He wrote me about it: The director of my lab is a very successful scientist. She is also director of the research facility. Our personalities blended well initially, but then we grew apart. She is very nice, very busy, and impressively ambitious. Despite her genuine desire to be nice, honest, and good teacher, her ambition is supreme — above honesty and integrity from my point of view.

Robin Hanson’s excellent essay in Cato Unbound is a proposal to cut medical spending in half. The evidence suggests that this would do little harm and it would help us focus on more helpful activities. I like the way this article summarizes the RAND experiment, searches for the right metaphor, and answers objections.