Month: April 2011

Scientific Illiteracy at The New Yorker

Seth Roberts5 Comments

A week ago, this passage appeared in an article about timing and the brain:

If you’re hiking through a jungle and a tiger growls in the underbrush, your brain will instantly home in on the sound by comparing when it reached each of your ears, and triangulating between the three points. The difference can be as little as nine-millionths of a second.

As if people had three ears. “Triangulating between the three points” is gibberish. The between-ear time-of-arrival comparison gives you a direction, not a location (which is what triangulation does). Perhaps it was added by a copy editor. If you delete it, the passage makes sense.

Wouldn’t that make a nice newsbreak (one of The New Yorker’s column-ending “Funny Usage Mistakes Made by Other Publications”)? I tried to submit it but couldn’t. So I wrote a Letter to the Editor about it.

In this week’s issue, Hendrik Hertzberg, the magazine’s main editorial writer, calls the idea that “global warming is a hoax” a “denial of reality”. He lumps it with birtherism and the ideas that “evolution is just another theory, on a par with the theory that the earth is six thousand years old.” In case you are reading this blog for the first time, I’ll say it again: Claims that humans have dangerously warmed the planet are based on climate models that are far from fully verified. That these models manage to fit past temperatures means little because the models have many adjustable parameters. Alas, this was no over-zealous editing mistake.

Assorted Links

Seth Roberts7 Comments
  • This study suggests calcium supplements are dangerous. They can raise your risk of heart attacks. There are probably better ways to reduce osteoporosis.
  • Conventional clinical trials overstate the value of drugs, says this paper. One reason is that they compare drug to placebo. In clinical practice, the choice is never drug or placebo; it is drug or other treatment (usually a different drug). “We need to put an end to this kind of gaming of the system” — a system in which standards of evidence grossly favor drug companies at the expense of everyone else.
  • Doctors use patient’s need for help to remove bad reviews. “The doctors simply make their patients sign a contract handing over the copyright of any review they might publish online afterwards. So, if the patients post any bad review, the company is able to send a DMCA notice demanding that the content be removed immediately.”
  • The end of mercury amalgam in dentistry.
  • paleolithicdiet.com, a new site from the founder of Paleohacks

10 Years of Weight Measurements: What Was Learned

Seth Roberts3 Comments

For ten years Alex Chernavsky has measured and recorded his weight (above). I asked what he learned from this. Here’s what he said:

I started the tracking because I thought that the very act of measuring (and recording) my weight every day would inspire me to lose weight. I don’t think it really worked that way, though. In order to lose weight, I had to take active measures.

What did I learn? I learned that low-carb diets work well in the short-run (as you said), and I also learned that eating low-carb is far, far easier than eating a calorie-restricted diet (which I’ve tried in the past, before I began recording my weight daily). I learned that regular exercise does lead to weight loss, although I can’t rule out a possible confounding factor: I wouldn’t be surprised if it turned out that I changed my eating habits at the same time that I started an exercise regime. That’s probably what Gary Taubes would claim.

I also learned that the Shangr-La diet works well for me. I think that the current upward trend is caused (at least in part) by the fact that I’m eating breakfast more and more often. I didn’t start eating breakfast until sometime last autumn. I will try eliminating breakfast again to see if it reverses the trend. I must say, though, that it’s a little difficult to watch my wife eating some scrumptious morning meal while I just drink coffee. The temptation is hard to resist.

I also learned that my weight fluctuates for no apparent reason at all. If you look at the period of roughly April 20, 2008 through mid-July 2008, you’ll see a drop of about ten pounds. I remember being surprised and puzzled during this time, because I could not think of any plausible reason why this weight loss would occur. I still don’t know. In any case, it was short-lived.

I also learned that I should have kept much better notes about what was going on during those ten years. I’m kicking myself now. I plan on continuing to collect data, and I will try to annotate the data better in the future.

My comments here.

The Kennedys (TV mini-series)

Seth Roberts1 Comment

This reviewer hated it, this reviewer panned it (“trivializes history”), but I loved it. Never has “behind every great fortune lies a great crime” (here, a great criminal, Joe Kennedy) been so well dramatized. Yet I came away from this series executive-produced by a Republican with a higher opinion of JFK and Bobby.

When I was in sixth grade, I did a survey in which I phoned random strangers and asked them history questions. To my chagrin, one of my “correct” answers (to the question “what year was the Bay of Pigs?”) was wrong. Until I watched this series, I didn’t really know what the Bay of Pigs was. Until I watched this series, I didn’t know important details of several other big events of the time, such as the struggle to admit James Meredith to the University of Mississippi. Supposedly JFK threatened the Governor of Mississippi with loss of all future NCAA Bowl invitations. “You can’t do that!” said the Governor. Surely fictional, but a nice touch.

Efficiency Measurement Update

Seth Roberts4 Comments

Here is another example of the efficiency graphs I’ve blogged about (here, here and here). The line is the current day; it shows how well I’m doing compared to previous days. It goes up when I work, down during breaks. The number in the right corner (“77″) is the percentile of my current efficiency (at the time the graph is made) compared to measurements within one hour (e.g., a measurement at 2 pm is compared to previous measurements between 1 pm and 3 pm).

The blue points come from before I started the feedback; the green points, afterwards. The red and black points are the final points of a day (that is, at quitting time). That the green points are above the blue points suggests that the graphical feedback helped. Here is a better way of seeing the effect of the feedback.

I didn’t expect this, as I’ve said. It is not “the effect of feedback”; before the graphical feedback, I’d gotten non-graphical feedback. It is a comparison of two kinds of feedback.

Why was the new feedback better? Here’s my best guess. It helped a little that it was pretty (compared to text). It helped a lot that it was in percentile form (today’s score compared to previous scores). This meant the score was almost never bad (from the beginning the percentile was was usually more than 50) and yet could always be detectably improved (e.g., from 68 to 70) with a little effort. I wish I could get such continuous percentile feedback in other areas of life – e.g., while treadmill running. I think feedback works poorly when it is discouraging or unpleasant and when it is too hard to improve. When I taught a freshman seminar at Berkeley, I got feedback (designed by a psychology professor) that was so unpleasant I stopped teaching freshman seminars. Because it came only at the end of the term, it was hard to improve — you’d have to teach the class again to get a better score. Moreover, it compared your score to everyone else’s. I think I was in the lower 50%, which I found really unpleasant. There was no easy way to give feedback about the feedback; maybe it is still in use.

In contrast, I love the feedback shown in the upper graph. Not only does it really help, as the lower graph shows, it leaves me at the end of the day with a feeling of accomplishment.

Assorted Links

Seth Roberts1 Comment

Thanks to Peter Spero and VeganKitten.

Roche is Deceptive and Evasive

Seth Roberts6 Comments

In an article about Tamiflu, an anti-flu drug developed by Roche, Helen Epstein writes:

[Non-Roche researchers] noticed yet more discrepancies between the articles that had appeared in scientific journals and Roche’s internal documents, many concerning the drug’s safety. According to published articles, no potentially drug-related serious side effects—or “serious adverse events” as they are called—were reported in the papers describing two Roche-sponsored clinical trials in which 908 people took Tamiflu; but according to Roche’s unpublished documents, three “serious adverse events” that were possibly related to Tamiflu occurred in these trials.

In 2008, an article in the journal Drug Safety, signed by a group of Roche authors, claimed that rats and mice, both given a very high dose of Tamiflu, showed no ill effect. But according to documents submitted to the Japanese Ministry of Health, Labor, and Welfare by Chugai, the Japanese Roche subsidiary, the exact same dose of Tamiflu killed more than half of the animals. As they died, the rats exhibited many of the same central nervous system symptoms that Hama had described in his case series on the Japanese children.

That’s deceptive. Here’s evasive:

“Do the ‘full study reports’” containing all five modules exist?” I asked my correspondent at Roche. “A simple ‘yes’ or ‘no’ answer will do.” In reply, she did not say “yes” or “no,” but repeated her claim that the Cochrane group had all the information it needed to analyze the Tamika studies.

This sort of thing is why I don’t trust drug companies. They’re dishonest again and again, with trivial consequences. Epstein’s article would have been even better had she given the names of the Roche employees she criticizes (the authors of the deceptive studies, the evasive correspondent).

Personal Science and Lyme Disease

Seth Roberts13 Comments

Here is a website devoted to a new way to cure Lyme disease: ingesting large amounts of Vitamin C and salt. The website is vague about who made it but it certainly isn’t a for-profit enterprise. It begins:

After 13 years of suffering with Lyme disease, a possible cure has been stumbled upon. A cumulative effect of much research has produced the possibility that salt and vitamin C may be all that is needed to beat this elusive illness. Without going into a lot of detail, our theory is that Lyme is not just a bacterial disease, but also an infestation of microfilarial worms. . . From experimenting with the treatment of salt and vitamin C, we settled on a dosage of 3 grams of salt and 3,000 mg of vitamin C, each dose taken 4 times per day. . . . The Treatment can be grueling; taking it with food may aid in digestion. The results [= the improvement] should be almost instantaneous.

Unsurprisingly, people a naive person might think would be interested turned out to be not be interested:

We have tried on three occasions to get help [= interest in our findings] through the CDC to no avail. The responses were things such as: thanks, we’ll forward to a lyme researcher; or, we don’t accept contributions or downloads from individuals; or, these pictures are obviously fakes. . . . We tried the university routine. A public health researcher put us onto a microbiology chair, who sent us to a CDC parasitologist, who said he wasn’t a clinician and suggested a pathologist. . . . We tried the most noted lyme sites on the web. We were disappointed that most of them seem more concerned with fundraising than disease.

Which sounds like “we” is one person — a man. In any case, I hope “they” will allow outsiders to contribute experiences, perhaps by adding forums to the site. This is terrific work.

Ten Years of Weight Measurements

Seth Roberts9 Comments

Alex Chernavsky, whose Shangri-La Diet experience I described recently, has recorded his weight for almost ten years, with the results shown in this graph. During that period, he’s changed his diet and exercise several times.

The first change was to a low-carb diet (Atkins-like, with lots of meat and fat). He made this change after reading Gary Taubes’s New York Times article “What If It’s Been A Big Fat Lie?”. As advertised, the low-carb diet caused him to lose a lot of weight but — not as advertised — after about a year he started to regain the lost weight. For other reasons, he changed to a vegetarian and later a vegan diet. They slowed down the weight regain but did not stop it. In 2005 and 2006 he managed by walking a lot — in 2006, 90 minutes/day or more 5 or 6 days every week — to lose almost 30 pounds, but then his weight resumed creeping upward. Then he lost about 30 pounds due to the Shangri-La Diet. He did the diet by drinking 3.5 tablespoons of flaxseed oil instead of lunch. He drank a glass of water afterwards to get rid of the flavor.

I have never seen a weight record this long. It suggests several interesting points:

1. A low-carb diet, as advertised, quickly produces substantial weight loss.

2. Not as advertised, the weight loss is followed by regain after a year or so. This implies that studies of low-carb diets and weight loss need to last several years to give a clear picture of how much weight loss to expect.

3. Low-intensity long-duration exercise (walking for 90 minutes almost daily) causes substantial weight loss. This isn’t surprising.

4. … but it is surprising the effects of the exercise appeared to last at least a few years after the exercise was stopped. I have never seen this reported.

5. The Shangri-La Diet worked well. Alex did the diet somewhat differently than other people so it was not obvious this would be true.

6. After he stopped losing weight on SLD, his rate of weight gain was roughly the same as his rate of gain before he started the diet.