Seth's Blog

At Berkeley, Andrew Gelman and I taught a freshman seminar about left-handedness. Half the students were left-handed. We did two fascinating studies with them that found that left-handers tend to have left-handed friends. I kick myself for not publishing those results, which I bring up in conversation again and again.

After the class ended I got a call from a journalist who was writing an article about ridiculous classes. I told him the left-handedness class had value as a way of introducing methodological issues but all I cared about was that his article be accurate. He decided not to include our class in his examples.

Stephen Christman, who got his Ph.D. from Berkeley (and did quirky interesting stuff even as a graduate student), and two colleagues have now published a paper that is a considerable step forward in the understanding of handedness. They argue that what really matters is not direction of handedness but the consistency of it. The terms left-handed and right-handed hide a confounding. Right-handers almost all have very consistent handedness (they do everything with the right hand). In contrast, left-handers much more often have inconsistent handedness: they do some things with the left hand, some with the right. I am a good example. I write with my right hand, bat and throw left-handed, play tennis left-handed, ping-pong right-handed. In fact, I am right-wristed and left-armed. When something involves wrist movement (writing, ping-pong) I use my right hand. When something involves arm movement (batting, throwing a ball, tennis), I use my left hand. Right-handers are much more similar to each other than left-handers.

Christman and his co-authors point to two things: 1. When you can get enough subjects to unconfound the two variables, it turns out that consistency of handedness is what makes the difference. Consistent left-handers resemble consistent right-handers.  2. Consistency of handedness predicts many things. Inconsistent-handers are less authoritarian than consistent-handers. They show more of a placebo effect. They have better memory for paragraphs. And on and on — about 20 differences. It isn’t easy to say what all these differences have in common but maybe inconsistent-handers are more flexible in their beliefs. (Which would explain the friendship findings in our handedness class.)

I think about these differences as another example of how every economy needs diversity and our brains have been shaped to provide it, one idea underlying my theory of human evolution. Presidents of the United States are left-handed much more than the general population. For example, Obama is left-handed. The difference between Presidents and everyone else is overwhelming and must mean something. Yet left-handers die younger. I would say that in any group of people you need a certain fraction, not necessarily large, to be open-minded and realistic. That describes inconsistent-handers (who are usually left-handed). These people make good leaders because they will respond to changing conditions. People who are not open-minded make good followers. Just as important as realism is cooperation, ability to work together toward a common goal.

Do the heads of eBay and Amazon know about the Chinese shopping site Taobao (like eBay without auctions)? If so, why don’t they imitate it? Maybe they can’t match its bigger selection (e.g., food, detergent) and better prices, but they could imitate the better seller feedback and instant communication (chat boxes) with sellers.

In my theory of human evolution I propose that we have ceremonies, rituals, and festivals (and associated holidays) because they caused trading that would otherwise not have taken place. Ceremonies and so forth increased the demand for certain goods — gifts and high-end clothes, for example. These goods are important economically far out of proportion to their volume or monetary value or daily use because they increase innovation. They help the most skilled artisans– the ones most likely to innovate — make a living.

The leaders of Taobao understand this function of festivals/holiday and have put it to use: They have created new festivals/holidays. The biggest is Double Eleven (November 11), which started five years ago. On Double Eleven, a large fraction of taobao merchants have discounts, big (50%) and small (5%). Sales have grown each year and this year reached about $3 billion, according to one site. According to a Chinese friend, the sales were about $10 billion. CyberMonday (about $1 billion in 2011) is far behind

I have never read about this function of ceremonies, festivals, etc., in any economics book or paper. Double Eleven shows their economic force. This neglect is an example of what I consider the biggest problem with modern economics: lack of attention to and lack of understanding of innovation.

• Olive oil and the Willat Effect. “You can read about great olive oils, and their vast superiority over bad oils, all you want. . . . But until you try first-rate olive oil for yourself – actually put the good stuff in your mouth, and compare that experience to the bad stuff you’ve eaten in the past – you won’t really get it. . . . . Once you taste fine olive oils and their low-class imitations [side by side], though, you start to care.”
• Petraeus Affair: The journalism of what we don’t know.
• Tucker Max on book publishing. Disruptive innovation for popular authors.
• Animal self-medication. Sick animals eat differently than healthy animals.

Thanks to Alex Blackwood.

During my last visit to New York I bought a new black tea. I started drinking it a few weeks ago. I brewed it various ways (different amounts of tea, different steeping times, etc.) but had a hard time telling which way was best. This morning I decided I would learn how to  brew it by making paired comparisons (two cups of tea made the same way at the same time except for one difference). The fascinating thing, as I’ve said, about these side-by-side comparisons is that they produce hedonic changes. They change how much you like this or that. I call this the Willat Effect after my friend Carl Willat who caused me to notice it.

This morning I made two cups of the new tea. The two cups were brewed the same except in one case I “rinsed” the tea before brewing. Rinsing means I poured a bit of hot water on it and quickly got rid of the hot water. Rinsing tea removes from the final product whatever is transferred from the tea to the hot water in the first few seconds. In China, rinsing tea is common; in the United States, very rare.

I tasted the two cups (rinsed and unrinsed) side by side. The rinsed tea tasted much better. The unrinsed tea had something weird about it. Ugh, I thought, I can’t drink this. I threw out the unrinsed tea. Over the previous few weeks, I had happily drunk the new tea unrinsed many times. Now I found it repulsive.

• Did Jules Hoffman deserve the 2011 Nobel Prize in Medicine/Physiology? “Jules again, in his very subtle manner, described the Toll story as a team-work. I sat there, nauseated.”
• Babies given antibiotics more likely to be obese at age 3. This is very likely cause and effect because it is well-established that giving livestock antibiotics makes them fat.
• Lynn Yaeger on collecting. “I’ll be trying to get to the bottom of the mystery of what makes otherwise sane people spend all their money on King George coffee mugs.”
• Cultured Food Life
• Pushcart kombucha
• Sky natto

Thanks to Adam Clemens.

A new BBC series Metalworks! is about the history of British metal working. My theory of human evolution says that decoration — more precisely, our enjoyment of it — evolved because it helped the most skilled craftsmen make a living. Long ago, technology evolved via massive amounts of trial and error, which required subsidy since payoff (discovery with practical value) was so infrequent. It was much easier to discover/learn how to make something that looked better than something that worked better, but the two sorts of discoveries were correlated: trial and error produces both.

The episode on ironwork (The Blacksmith’s Tale) makes explicit how desire for decoration made it easier for the most skilled iron workers to make a living:

[Expert, at 16:50:] “I think decoration entirely depends on the amount of money the patron wanted to spend on that particular object.” [Narrator:] By the end of the 15th Century, wealthy patrons, such as the Church and monarchy, were hand-picking known craftsmen at the top of their game to match a commission’s requirements. When King Edward IV commissioned the Cornish smith John Tresillion to make these Gothic gates at Windsor in 1497, he did so with good reason. . . . [Expert:] “No blacksmith, ordinary blacksmith who was used to making horseshoes, could dream of working to this standard of perfection.”

Quality of decoration is easy to see. It doesn’t matter but it correlates with something that does matter — amount of trial and error (more trial and error, more innovation). We reward decoration to increase innovation.

The Shangri-La Diet derives from a theory of weight control that emphasizes smell-calorie learning. Smell-calorie learning evolved for the same logical reason. Smells don’t actually matter for health. But they are easy to notice and they correlate with things that do matter for health, such as calories. Via smell-calorie learning we learn the correlations. After that the foods that smell best are the ones that contain more calories.

Carl Willat, for whom the Willat Effect is named, wrote to me:

I had two cartons of half and half in the fridge, neither had reached its expiration date but one was three days newer. I wondered if I could taste the difference between them, and I found that I could. Neither was sour, but one tasted fresher. I made a batch of vanilla ice cream out of each of them, figuring that together with the other ingredients I was adding (vanilla, egg yolks, cream, salt and sugar) the difference in taste would be less noticeable. After putting both mixtures through the ice cream freezer I tasted them [side by side] and one tasted a lot better. I gave a friend of mine a spoonful of each and she immediately noticed the difference. She correctly identified the good one and described it as tasting fresher and lighter. I can’t bear to eat the less good batch and I don’t know what to do with it. I don’t want to give it away for fear someone will think it representative of what my ice cream tastes like. I’m sure in the past I’ve made plenty of ice cream of this same quality that I and everyone else thought was perfectly acceptable, even delicious.

The fascinating part is “can’t bear to eat the less good batch”. Same thing with me and tea: In the last half year or so, I’ve made hundreds of side-by-side comparisons of tea. I now throw away cups of tea I don’t like. I never used to do that.

A month ago I bought three identical tea pots to compare tea side by side. I hoped to take advantage of the Willat Effect (side-by-side comparisons create connoisseurs) to become a tea connoisseur.

It worked. Side-by-side tea comparisons are fun, easy, and have taught me a lot. When I drink tea I notice more and like it more. I do about three comparisons per day. I blogged about the first results here. The most useful idea about these comparisons came from Carl Willat himself: Compare the same tea brewed differently (e.g., different amounts of tea, different brewing times, different water temperatures). Most of my comparisons vary amount of tea or brewing time.

These many  comparisons have had several effects: (more…)

I have had tea daily for the last ten years, ever since I discovered the Shangri-La Diet. A few weeks ago, I started doing side-by-side comparisons of similar teas or the same tea prepared two ways (e.g., different brewing times). Would the Willat Effect make me a tea connoisseur?

Since then I have done at least one side-by-side comparison every day. It’s almost as easy as making an ordinary cup of tea and a lot more fun. These comparisons have taught me more about tea preparation than the previous ten years. I’ve learned:

1. The black tea I have (an Earl-Grey variant) tastes better when brewed for 3.5 minutes than 4.0 minutes.

2. The black tea tastes better when I use 1.5 grams of tea than when I use 2.0 grams of tea. (After starting these comparisons, I bought a scale for weighing tea.)

3. One of the green teas I have tastes better when “rinsed” for 30 seconds before brewing 1 minute than when simply brewed for 1 minute. In China, this preference (rinse green tea before brewing) is common. I was reminded of it by this comment and Paul Jaminet’s post about tea. Black tea is different, as I noted earlier.

4. I have a caffeine-free tea blend called Choco Late made of cacao husks, vanilla, and rooibos. The package says brew 5 minutes. Which is nonsense. It tastes better (fuller, more rounded) when brewed 30 minutes than when brewed 15 minutes. (I’ve noticed the same thing with caffeine-free chai blends. Enormous brewing times, like 60 minutes, produce much better results than short times.)

5. My most interesting discovery is when I brew Choco Late for 30 minutes it tastes so good I no longer want to sweeten it. It is pleasant enough already and sweetness would distract from the complexity, fullness, and slight bitterness. (At first I wrote “lovely complexity, fullness …”) I was shocked when I noticed this. It has never happened before.

This tea-selling website mentions the Willat Effect under the heading “Do you want to be a tea connoisseur?” I hope this means the idea will spread among the fancy-food community. They have a lot to gain from better understanding of how to make people connoisseurs. Many times I have asked people in that community what makes someone a connoisseur? The usual answer is education. In my case, Willat-Effect comparisons (side-by-side comparisons of similar teas) were far more powerful than reading about tea, drinking a variety of teas, going on tea tours, going to ordinary tea tastings (where you taste a wide range of teas), and talking about tea with experts. I have been to five or six Fancy Food Shows and have visited thousands of booths. Exactly one booth offered side-by-side comparisons of similar products. It was their product made with and without a special ingredient.

Willat-Effect comparisons are mini-science. They aren’t quantitative but they include three other things central to science: 1. Close comparisons. This is the essence of experimentation. 2. You don’t know the answer. 3. You care about the answer.

The Willat Effect is the hedonic change produced by side-by-side comparisons of similar products — for example, two green teas. It happens in seconds: Suddenly the differences matter more. Some versions become more pleasant, other versions less pleasant.  I first noticed it with limoncello that my friend Carl Willat offered me. Here are some reactions to my recent post about it: (more…)