- aftermath of the Marc Hauser case (via Andrew Gelman)
- career advice in mathematics
- seeing meat calms men down. This research, which has been covered by many newspapers, was done by an undergraduate.
Thanks to Vic Sarjoo.
Month: November 2010
Two Gmail Features I Want
Now that Gmail is out of beta, here are two suggestions for improvement:
1. Oldest first. I want to be able to sort my email so that the oldest is first on the list. That will make it harder to ignore or forget about. I can use the reward of seeing my latest email as inducement to deal with the oldest email. (I often bundle unpleasant and pleasant tasks: taking vitamins and drinking kombucha, doing pushups and listening to music, standing on one foot and watching Survivor.)
2. Delayed send (also called second thoughts). I want to be able to send email after a delay — say, one day. This has two advantages: it slows down the correspondence, and it gives me a chance to reconsider. An earlier email program I used had something like this and I was often glad I could revise what I’d written before it was sent.
More The Gmail Undo Send feature (available in Labs) gives you about 20 seconds to change your mind. Better than nothing but not nearly long enough.
Why I Am A Biological Psychologist
Sheena Iyengar, a professor at Columbia Business School, is best-known for a study she did in graduate school. When shoppers in a Menlo Park food store were offered much more choice of jams (24 rather than 6), they were less likely to buy one. In The Art of Choosing (2010), Iyengar wrote (p. 190):
Since publication of the jam study, I and other researchers have conducted more experiments on the effect of assortment size. These studies, many of which were designed to replicate real-world choosing contexts, have found fairly consistently that when people are given a moderate number of options (4 to 6) rather than a large number (20 to 30), they are more likely to make a choice, are more confident in their decisions, and are happier in what they choose.
In contrast, Benjamin Scheibehenne, a research scientist at the University of Basel, and two co-authors, who surveyed the literature, found the effect was hard to replicate:
The choice overload hypothesis states that an increase in the number of options to choose from may lead to adverse consequences such as a decrease in the motivation to choose or the satisfaction with the finally chosen option. A number of studies found strong instances of choice overload in the lab and in the field, but others found no such effects or found that more choices may instead facilitate choice and increase satisfaction. In a meta-analysis of 63 conditions from 50 published and unpublished experiments (N = 5,036), we found a mean effect size of virtually zero but considerable variance between studies
This reminds me of the learned-helplessness effect. When Martin Seligman, a psychology professor at Penn and recent president of the American Psychological Association, was a graduate student, he and his advisor reported that when you give dogs inescapable shock, they stop trying to escape or avoid the shock: learned helplessness. The effect turned out to be extremely hard to replicate, but this did not stop Seligman from having a brilliant career.
The Climate Change Bubble Has Burst?
How many climate change scientists does it take to change a light bulb? None. They all agree it will change.
Judging by these nine comments, a large fraction of Mother Jones readers think they’ve been had.
Dangerous Acne Medicine
Treatment of acne with isotretinoin is associated with suicide attempts, according to a new study. A puzzle is that suicide attempts started to rise before the treatment started. They sharply declined to baseline after treatment stopped.
Acne is an good target for self-experimentation because it is easy to measure and is surely related to diet. My discovery of the value of self-experimentation happened with acne: I discovered that of the two drugs my dermatologist had prescribed, one (benzoyl peroxide) worked, the other (tetracycline) didn’t. I had believed the opposite, that tetracycline worked and benzoyl peroxide didn’t work.
How to Choose A Research Topic
A few weeks ago, a female biology professor from Berkeley gave a talk at Tsinghua as part of a women-in-science series. During the question period, a student asked how to choose a research topic. You have a choice of labs; which should you choose? You have a choice of research questions; which should you choose? An excellent question: Every young scientist wonders about this.
The speaker’s answer: Believe in yourself. Huh? This came from her personal history. When she was a grad student (at Berkeley) she proposed a certain line of research to her advisor. Her advisor said it was a bad idea. She switched to Harvard and pursued her idea there. It paid off. A sign of her success is that her lab gets $1 million/year in grants.
I wasn’t there. The friend who told me the professor’s unhelpful answer asked how I would answer the same question. During graduate school, I thought a lot about it — about how to do research that anyone will care about in fifty years. I can answer it only for experimental psychology.
First，invent a new method or study a large puzzling experimental effect. With either one you can generate a steady steam of publications. Inventing a new method mean inventing a better way — usually, a faster way — of measuring something important. You can then apply your new method all over the place. With a large experimental effect you can vary all sorts of things and narrow in on an explanation. As a grad student, I took the first route: I used a new way of studying animal time discrimination. I didn’t invent it but its inventor hadn’t seen its value. An example of the second route is the career of John Garcia. In graduate school, he discovered that making rats sick after eating a new flavor caused them to dislike the flavor. The sickness could come hours after the flavor. Garcia made a whole career out of doing variations on this.
Second, take advantage of whatever is unusual about you. If you are unusually interested in X, study X. I differed in two ways from most experimental psychologists: I was better at math, and I cared more about writing. Taking advantage of this, I spent a lot of time on data analysis and writing. Both paid off. I suppose my paper were better written than necessary but the time spent on writing paid off because I got good ideas while writing.
Third, collect a rich data set. New experimental effects are enormously important — if you manage to find one you can spend the rest of your career studying it — but are also very difficult to find. You can’t do experiments whose main purpose is to look for them. The chances of success are too low. To find them, you set up your research so that a conventional experiment has the possibility of finding them. For that you need a rich data set — a data set with many factors and many levels of each factor, ideally. The new way of studying timing that I used provided a rich data set. Quite soon this led to discovering a new effect when some of the data changed in a surprising way.
A Theory of Human Evolution and Application to Education
A week ago I went to a cognitive science conference in Chongqing, where I gave a talk called “A Theory of Human Evolution and Application to Education” (a theme of the conference was education). A sponsor of the conference, a magazine called Scientific Chinese, will publish short versions of the talks. Here is the short version of my talk, only a little different than what I’ve said before but far more compact.
Humans specialize. We make a living thousands of ways. A dentist makes a living one way, a carpenter another, and so on. No other species does this. In every other species, all members of the species make a living in one or two ways. All sparrows search for and eat the same food, for example. I propose that human nature changed in several ways to make possible our extreme within-species specialization.
It started with hobbies. Hands, evolved to swing through trees, could also make tools. Tools saved time. They made it easier to hunt and prepare food. Hobbies were a good use of the spare time. It was better to do one thing repeatedly during your spare time (and become skilled at it) rather than do many different things. Because of this advantage, an across-day tendency to repeat (to do today what you did yesterday) evolved. This tendency not only caused hobbies, it also caused diversity of hobbies. It was hard to change hobbies, so choice of hobby became less sensitive to feedback (the payoff from doing the hobby). Today, this tendency to repeat across days causes procrastination. It is hard to start a job-like activity. Procrastination is so common and hard to avoid because the underlying tendency was so important.
Diverse hobbies led to trade. I give you what I make, you give me what you make.
Language began because it increased trade. It helped the two sides of a trade find each other. It started with single words. Single words made it easier to convey what you wanted: You said the word for it. They also made it easier to indicate what you made: You said the word for it. Someone else could say the word for what you made and point at you. The first conversation: Person 1: X? Person 2: X (pointing). English family names reflect this usage; many come from occupations. For example, smith means metal worker.
A healthy economy has three features: 1. Many goods and services. Diverse hobbies provided this. 2. Easy trade. Language provided this. 3. Innovation. A healthy economy creates new goods and services. This was encouraged by the evolution of desires for (a) current tools made better than necessary and (b) useless “tools”.
Demand for current tools made better than necessary came from the evolution of several tendencies. These tendencies produced behavior that is still common. First, gift-giving. Gifts are better-made versions of ordinary things. The “improvements” — the differences between the gift version and the ordinary version, such as a nicer package — are useless in the sense that neither giver nor recipient would buy the gift version for themselves. Second, holidays, festivals, and ceremonies. Holidays, festivals, and ceremonies create demand for fancy versions of ordinary things, such as special clothes, tools, and foods. For example, Japanese tea ceremonies use special tools and require special clothes. Third, connoisseurs, collectors, and souvenirs. Connoisseurs notice small improvements that most people don’t notice and pay for them. Collectors buy things that non-collectors would not buy or at least pay more for them. A collector of frog-related things might buy an eraser in the shape of a frog. Making an eraser look like a frog does not make it erase better. Souvenirs are usually ordinary objects (ashtray, pen, key chain) made more desirable. Souvenirs make anyone a collector.
The existence of gift-giving, holidays, and so on increased demand for finely-made things — better versions of ordinary things. Finely-made things were harder to make than ordinary things, so this demand pushed artisans to become more skilled. The more skilled an artisan, the more easily he could innovate. A skilled baker is more likely to invent a useful new bread than an unskilled baker.
The useless “tools” that promoted innovation are art, decoration, and music. Desire for art and decoration supported the development of new techniques and materials — new paints, for example. Music encouraged technical advances because better control of materials allowed you to make better-sounding musical instruments. The tendency behind fashion (year-to-year changes in preferences, and a desire for novelty) pushed artists and artisans to continue to innovate, to continue to develop new techniques and materials. They could benefit from innovating, but only for a limited time.
Art, decoration, and music allowed the development of revolutionary technologies — technologies that weren’t refined versions of old technologies. Can you invent metal by refining stone tools? No, you can’t. Endless trial-and-error while making stone tools will teach you how to make stone tools that are suitable for gifts, but it will never lead to metals. To produce something as different from its predecessors as a metal tool, you need to reward small steps on the way to getting there. This is what art does. Metal looks good. Long before our ancestors could make useful tools with metal (tools that could outperform existing tools), they could make art with metal.
The application to education is that this tendency to specialize in terms of job must be strong within us. The members of a group lived in the same place and had similar genes, yet there must have been powerful forces pushing them toward different jobs. Today these forces push students in different directions. The closer they get to being old enough to work, the more powerful these forces probably become, the more diversity they create. One reason I developed this theory is the diversity I saw in my own students. Within one undergraduate class, all psychology majors, I realized there were big differences between students. After graduation, they would choose different jobs.
Most teachers ignore these differences. They treat all students alike. It is like trying to put shoes of different shapes and sizes into identical boxes. Most shoes won’t fit, no matter what box you use. Teachers who treat all students alike are fighting human nature. I learned to take advantage of the diversity of my students by giving them great choice. When I gave them enough choice, they found activities they really wanted to do. They did them enthusiastically and learned a lot. With human nature on my side, teaching became much easier.
The Size of Restaurant Tips
The size of tips left in restaurants has been the focus of considerable study. An early study found that brief contact increases tips. This study reviews the literature. Here is a study in a French bar.
Plagiarism by British Drug Tsar
Leslie Iversen, a retired Oxford professor of pharmacology, is Chair of the British government’s Advisory Council on the Misuse of Drugs. He is also a Fellow of the Royal Society, a foreign associate of the National Academy of Sciences, and chairman of the board and director of Acadia Pharmaceuticals, San Diego.
In 2008, Oxford University Press published a book by Iversen called Speed, Ecstasy, Ritalin: The Science of Amphetamines. Four passages in it are very close to a website about MDMA (Ecstasy). The duplicated material was on the website in 2002.
Iversen (p. 151): MDMA was profiled by the San Francisco Chronicle as ‘The Yuppie Psychedelic’ (10 June 1984). In Newsweek, J Adler (‘High on “Ecstasy”‘, 15 April 1985) likened his MDMA experience to ‘a year of therapy in two hours’”. Harpers Bazaar described MDMA as ‘the hottest thing in the continuing search for happiness through chemistry’. Unsurprisingly, MDMA use soon spread beyond the couch and clinic to the wider world. MDMA’s now universal brand-name, “ecstasy”, was coined in 1981 by a member of a Los Angeles distribution network. The unnamed distributor apparently chose the name “ecstasy” because ‘it would sell better than calling it “Empathy”. “Empathy” would be more appropriate, but how many people know what it means?” (Eisner 1989). Condemned by purists as a cynical marketing ploy, the brand-name ‘ecstasy’ isn’t wholly misleading ( ecstasy: “an overpowering emotion or exaltation; a state of sudden intense feeling. Rapturous delight. The frenzy of poetic inspiration. Mental transport or rapture from the contemplation of divine things’ (Oxford English Dictionary)). Many first-time MDMA users do indeed become ecstatic. Some people report feeling truly well for the first time in their lives.
Website: MDMA was profiled by the San Francisco Chronicle as “The Yuppie Psychedelic” (10 June 1984). In Newsweek, J Adler [“High on ‘Ecstasy”, April 15 1985] likened his MDMA experience to “a year of therapy in two hours”. Harpers Bazaar described MDMA as “the hottest thing in the continuing search for happiness through chemistry”. Unsurprisingly, MDMA use soon spread beyond the couch and clinic to the wider world. MDMA’s now universal brand-name, “Ecstasy”, was coined in 1981 by a member of a Los Angeles distribution network. The unnamed distributor , quoted in Bruce Eisner’s Ecstasy: The MDMA Story (1989), apparently chose the name “Ecstasy” because “it would sell better than calling it ‘Empathy’. ‘Empathy’ would be more appropriate, but how many people know what it means?” Condemned by purists as a cynical marketing ploy, the brand-name “Ecstasy” isn’t wholly misleading [ecstasy: “an overpowering emotion or exaltation; a state of sudden intense feeling. Rapturous delight. The frenzy of poetic inspiration. Mental transport or rapture from the contemplation of divine things”]. Many first-time MDMA users do indeed become ecstatic. Some people report feeling truly well for the first time in their lives.
Iversen (p. 157-158): Pure MDMA salt is a white crystalline solid. It looks white and tastes bitter. The optimal adult dose of racemic MDMA is about 120-130 mg (around 2 mg/kg body weight). Pills sold in clubs often contain less. There are gender differences in response; proportionately to body weight, women are more sensitive than men to the effects of MDMA and so their optimal dosage may be lower. The preferentially metabolised (+)-enantiomer (‘mirror image’) of MDMA is more active, more stimulating, and more neurotoxic than the (-)-enantiomer. MDMA is usually taken orally as a tablet, capsule, or powder.
Website: Pure MDMA salt is a white crystalline solid. It looks white and tastes bitter. The compound is chemically stable. MDMA does not readily decompose in heat, air or light. The optimal adult dose of racemic MDMA is probably around 120-130 mg [around 2 mg/kg of body weight i.e. about 125mg] but optimal dose ranges from perhaps 75mg to as much as 250mg. Pills sold in clubs often contain less. There are gender differences in response; proportionately to body-weight, women are normally more sensitive than men to the sub-acute and longer-term effects of MDMA, so their optimal dosage may be lower. The preferentially metabolised (+)-enantiomer (“mirror image”) of MDMA is more active, more stimulating, more dopaminergic, more subjectively rewarding, and more neurotoxic than the (-)-enantiomer. MDMA is usually taken orally as a tablet, a capsule, or a powder.
Iversen (p. 158): … can promote an extraordinary clarity of introspective self-insight, together with a deep love of self and a no less emotionally intense empathetic love of others. MDMA also acts as a euphoriant. The euphoria is usually gentle and subtle; but is sometimes profound.
Website: … can promote an extraordinary clarity of introspective self-insight, together with a deep love of self and a no less emotionally intense empathetic love of others. MDMA also acts as a euphoriant. The euphoria is usually gentle and subtle; but sometimes profound.
Iversen (p. 159): MDMA is sensuous in its effects without being distinctively pro-sexual; it is more of a hug-drug than a love-drug. However, MDMA’s capacity to dissolve a lifetime’s social inhibitions, prudery, and sexual hang-ups means that lovemaking while under its spell is not uncommon. In men, orgasm is more intense than normal but is delayed: MDMA retains a residual sympathomimetic activity, triggering a detumescence of the male organ. To ease MDMA-induced performance difficulties, flagging Romeos increasingly combine Ecstasy with Viagra.
Website: MDMA is sensuous and sensual in its effects without being distinctively pro-sexual. Although once dubbed “lover’s speed”, MDMA is proverbially more of a hugdrug than a lovedrug: “I kissed someone I was in love with and almost felt as if I was going to pass out from the intensity”, recalls one American clubber. However, MDMA’s capacity to dissolve a lifetime’s social inhibitions, prudery and sexual hang-ups means that lovemaking while under its spell is not uncommon. Superfluous clothes tend to get shed. In men, orgasm is more intense than normal but delayed: MDMA retains a residual sympathomimetic activity, triggering a detumescence of the male organ. To ease MDMA-induced performance difficulties, flagging Romeos increasingly combine Ecstasy with Viagra.
Bold type indicates differences between the book and the website. University of Oxford policy on plagiarism. Plagiarism by Harvard professors.
Why Small Change = Big Deal (revised)
Last week a journalist asked me why the 5% improvement in arithmetic speed produced by butter was important. In an earlier post I said I’d given a poor answer. A few days later I figured out what I should have said. The article was delayed, it turned out, so there was time to use my new strategy. I answered the question like this:
I was excited by this discovery because it was so big and unexpected. Someone once found a correlation between IQ and reaction time. The higher your IQ, the faster your reaction time. I don’t know what the exact function was but a decrease of 30 milliseconds might correspond to 10 more IQ points. I felt a little bit smarter. It was so unexpected because hardly anyone was going around saying butter is good for you — and thousands of people were saying it is bad for you. The only ones saying butter is good for you were the followers of Weston Price, and they had almost no evidence for what they were saying. Compared to their evidence, my evidence was crystal clear. Among mainstream nutritionists, butter is universally scorned. Yet my data suggested exactly the opposite — that it had a large amount of an important nutrient I wasn’t getting enough of. If mainstream nutrition advice could be so wrong, it would have big implications for what we eat. Maybe other things we are constantly told about what to eat are also wrong.
I discovered this big effect of butter by substituting butter for pork fat. So the reason butter was so helpful wasn’t anything as simple as animal fat is food for us. I ate plenty of animal fat before I started eating lots of butter. The reason was something more specific.