Seth's Blog

• Gary Taubes on bloggingheads. Mentions self-experimentation toward end.
• Beijing bans ancient history. “[China's] leaders are now delegitimizing themselves, one harsh act at a time.”

Thanks to David Gerard.

Darwin was an insider/outsider; so was Mendel. Insider/outsiders are close enough to their subject to have a good understanding and skills yet far enough away to have freedom. In the case of Chinese history, a journalist named Yang Jisheng has filled that role. He wrote a book called Tombstone (Mubei) about the Great Famine (1958-61). He was able to write what professional historians could not:

Why are you the first Chinese historian to tackle this subject seriously?

Traditional historians [i.e., college professors] face restrictions. First of all, they censor themselves. Their thoughts limit them. They don’t even dare to write the facts, don’t dare to speak up about it, don’t dare to touch it. And even if they wrote it, they can’t publish it. And if they publish, they will face censure. So mainstream scholars face those restrictions.

But there are many unofficial historians like me. Many people are writing their own memoirs about being labeled “Rightists” or “counter-revolutionaries.” There is an author in Anhui province who has described how his family starved to death. There are many authors who have written about how their families starved.

“If they publish, they will face censure.” With respect to weight control, I am an insider/outsider. When I published The Shangri-La Diet, I did not expect censure. My colleagues (other psychology department faculty)  wouldn’t care what I wrote about a different subject. To my surprise, I was censured — maybe a better word is denounced — by a nutrition education lecturer in the UC Berkeley Nutrition Department.  The woman who denounced me had not seen my book. Based on what a reporter told her, she expressed her opinion of it in an email she sent to twenty people in her department and the chairman of my department. It said, in part:

I did give the SF Chronicle reporter my opinion of the diet making these points:
- one cannot possibly meet nutrient needs on 1200 kcals per day
- sugar and oils are not nutrient dense; they are calorically dense and thus dilute the nutrient density of the total kcal intake.
- 1200 kcals per day is less than the semi-starvation diet used in the only published formal study ever conducted in this country on human starvation (Ancel Keys, 1950)
- human semi-starvation is not a path to health whether one is discussing physical, psychological, or social well-being
- the results of single subject research are applicable only to that subject; they cannot be generalized to others.
- I cannot recommend this diet, in fact, I recommend against it.

In other words: Ridiculous. Her many misconceptions (e.g., she is unaware of many examples of path-breaking self-experimentation in the field of nutrition)  aren’t terribly interesting. What’s fascinating is her decision to trash a book she hasn’t read to a large number of her colleagues.

Thanks to Steve Hansen.

• Most epidemiology papers I’ve seen do too many tests, which has the same effect as throwing away data. However, the criticisms of epidemiology I’ve seen are often too harsh (e.g., epidemiology is worthless). The next time someone criticizes epidemiology, point them to these three papers on prenatal pesticide exposure and IQ.
• positive reinforcement training improves chimp welfare
• Rajiv Mehta introduces  Tonic, an app to help you remember and track recurring events, such as taking medicine. Video.
• The STAR*D scandal (STAR*D was a large study of the effectiveness of antidepressant drugs).
• The statin scandal. “The years 2008 and 2009 [were] very disappointing for cholesterol experts and the cholesterol drug industry.” Via Steve Hsu. Statins are expensive and have serious side effects — and it is now clear they are close to worthless. My half-stick of butter/day is looking better and better. (Link fixed.)

Demand pricing (also called dynamic pricing) is adjusting the price according to demand. More demand, higher price. It is being considered for movie tickets:

If a movie is hot, the price could rise to whatever the market will bear. For example, I’d have paid $20 per ticket to see “Avatar” in 3-D when it first opened; maybe others would have been willing to pay even more. As demand becomes clear through lower ticket sales, prices would drop. So “Avatar” might cost $15 a few weeks after opening, gradually making its way to $10.

The theory behind the Shangri-La Diet says that body fat is adjusted in a similar way. When food is abundant, the set point (which controls how much fat you have) goes up (= you store more fat). When food is scarce, the set point goes down. This is how many storage systems work, of course; they increase the amount stored when the price is low and decrease the amount stored when the price is high.

Perhaps one day weight control will be explained to children by telling them it is like the price of airplane tickets: “When more people want to go to Los Angeles, the price goes up. When more food is available, your set point goes up . . . “

Warning: This post, written for the Quantified Self blog, has more repetition than usual of material in earlier posts.

In January, after talking with Matthew Cornell, I decided to measure my work habits. I typically work for a while (10-100 minutes), take a break (10-100 minutes), resume work, take another break, and so on. The breaks had many functions: lunch, dinner, walk, exercise, nap. I wanted to do experiments related to quasi-reinforcement.

I wrote R programs to record when I worked.  They provided simple feedback, including how much I had worked that day (e.g., “121 minutes worked so far”) and how long the current bout of work had lasted (e.g., “20 minutes of email” — meaning the current bout of work, which was answering email , had so far lasted 20 minutes).

I collected data for two months before I wrote programs to graph the data. The first display I made (example above) showed efficiency (time spent working/time available to work) as a function of time of day. Available time started when I woke up. If I woke up at 5 am, and by 10 am had worked 3 hours, the efficiency at 10 am would be 60%. The display showed the current day as a line and previous days as points. During the day the line got longer and longer.

The blue and red points are from before the display started; the green and black points are from after the display started. The red and black points are the final points of their days — they sum up the days. A week or so after I made the display I added the big number in the upper-right corner (in the example, 65). It gives the percentile of the current efficiency compared to all the efficiency measurements within one hour of the time of day (e.g., if it is 2 p.m., the current efficiency is compared to efficiency measurements between 1 p.m. and 3 p.m. on previous days).

I started looking at the progress display often. To my great surprise, it helped a lot. It made me more efficient. You can see this in the example above because most of the green points (after the display started) are above most of the blue points (before the display). You can also see the improvement in the graph below, which shows the final efficiency of each day.

My efficiency jumped up when the display started.

Why did the display help? I call it percentile feedback because that name sums up a big reason I think it helped. The number in the corner makes the percentile explicit but simply seeing where the end of the line falls relative to the points gives an indication of the percentile. I think the graphical display helped for four reasons:

1. All improvement rewarded, no matter how small or from what level. Whenever I worked, the line went up and the percentile score improved. Many feedback schemes reward only a small range of changes of behavior. For example, suppose the feedback scheme is A+, A, A-, etc. If you go from low B- to high B-, your grade won’t change. A score of 100 was nearly impossible, so there was almost always room for improvement.

2. Overall performance judged. I could compare my percentile score to my score earlier in the day (e.g., 1 pm versus 10 am) but the score itself was a comparison to all previous days, in the sense that a score above 50 meant I was doing better than average. Thus there were two sources of reward: (a) doing better than a few hours ago and (b) doing better than previous days.

3. Attractive. I liked looking at the graphs, partly due to graphic design.

4.  Likeable. You pay more attention to someone you like than someone you don’t like. The displays were curiously likable. They usually praised me, in the sense that the percentile score was usually well above 50. Except early in morning, they were calm, in the sense that they did not change quickly. If the score was 80 and I took a 2-hour break, the score might go down to 70 — still good. And, as I said earlier, every improvement was noticed and rewarded — and every non-improvement was also gently noted. It was as if the display cared.

Now that I’ve seen how helpful and pleasant feedback can be, I miss similar feedback in other areas of life. When I’m walking/running on my treadmill, I want percentile feedback comparing this workout to previous ones. When I’m studying Chinese, I want some sort of gentle comparison to the past.