Archive for September, 2007

Walk and Write at the Same Time

Sunday, September 30th, 2007

My exercise research suggests our brains work better when we walk. Here’s one way to combine walking and writing:

While working on a paper, which was most of the time, [Niels] Bohr would select an assistant from among the young physicists in Copenhagen. The assistant, affectionately dubbed the victim, was supposed to sit in place while Bohr paced around the room, constantly puffing away at his pip, working and reworking his ideas, talking aloud as the idea took shape, trying and retrying to dictate his sentences to the victim.

From Faust in Copenhagen: A Struggle for the Soul of Physics by Gino Segre.

The modern version may be use of word recognition software with the computer screen on a wall or large TV. You walk back and forth in front of it. I have spent a lot of time writing while walking on a treadmill but it was noisy and tiring. Moreover, it was hard to start and stop and it was monotonous.

Marc Andreessen’s Career Advice

Sunday, September 30th, 2007

Marc Andreessen is starting a series of posts of what I am sure will be excellent career advice. This is from the first:

I believe a huge part of what people would like to refer to as “career planning” is being continuously alert to opportunities that present themselves to you spontaneously, when you happen to be in the right place at the right time. . . . [for example:]

* Your former manager has jumped ship to a hot growth company and calls you three months later and says, come join me.

I am continually amazed at the number of people who are presented with an opportunity like one of the above, and pass. There’s your basic dividing line between the people who shoot up in their careers like a rocket ship, and those who don’t — right there.

A friend of mine worked at UC Berkeley with Bill Joy, one of the founders of Sun Microsystems. One day he got a call from Joy: Want to join me at Sun? My friend would have been employee #5 — something like that. He said no. It was a huge mistake, just as Andreessen says.

A Story About Data

Sunday, September 30th, 2007

While introducing Justin Wolfers as guest blogger at Marginal Revolution — which I am greatly looking forward to, since Wolfers is an excellent data analyst — Alex Tabbarok wrote:

An open secret and an open sin in economics is that many empirical studies are difficult to replicate, even when journals supposedly require authors to make their data publicly available.

Which reminds me. Several months ago, I read an article in a psychology journal about a topic I care a lot about. The conclusions of the article were the opposite of what I think is the case. Was I wrong? Possibly — but the data analysis done in the article was unquestionably “wrong” in the sense that (a) it assumed something that was unlikely to be true and (b) it was possible to do a data analysis that didn’t make that unlikely assumption. I don’t think my opinion here is controversial; I think a blunt but fair summing up of the situation is that the authors made a big mistake.

I was in New Orleans a few weeks after the article appeared. Someone in an art gallery told me the conclusion of the paper! Which is only to say it is a really interesting conclusion. Anyway, I wrote to the first author of the paper (a graduate student) to explain my concern about their conclusions and to ask for the data, so I could do a better analysis. Two weeks went by, no answer. I sent a reminder email, and got this answer:

We typically do not give out our original data, but when I get a chance, I will run the analyses in HLM and get the results back to you. Thanks for your interest in the study,

Wow! It is the policy of the journal in which the paper was published that the data be made available. A month passed. When do you expect to run these analyses? I wrote. A month passed with no answer. I wrote to the faculty member who was a co-author on the paper. Finally I got an answer from the student:

I have been meaning to respond to your email & I apologize for not getting back to you sooner. I am a graduate student and am traveling for the summer. I understand the difficulty with the [blank] situation and am assuming that HLM would be a good way to work through that. However, I am not familiar with the procedure, so it will not be until late August/ early September when I can get a statistician here at [blank] to teach me the procedure. If you have specific suggestions about the analyses, please let me know and I will keep that in mind when I get a chance to work with it. We should have some follow-up data coming in as well so it will be good to learn the procedures for future research. Thanks for your interest in the study.

The story so far is uncomfortably close to what happened when Saul Sternberg and I questioned Ranjit Chandra‘s data. Similarity 1: He never provided the data. Similarity 2: It took a remarkably long time and several emails to get any response. Similarity 3: The response, when it finally came, was only vaguely reassuring. However, in this case, I predict the better analysis will actually be done. Which is good — I would rather someone else do them.

How Lucky I Feel

Sunday, September 30th, 2007

From an email to science-fiction author Bruce Sterling:

The main thing [most book] authors experience is THE VOID. We never get any feedback or at least never enough. I have a friend called Ruth who is 80 years old and reads voraciously: novels, biographies, poetry. She writes to the authors she likes and gets back extraordinary responses: four pages hand written, invitations to dinner. She says, ‘I would have thought they were too important to read my letters’ and I say ‘Ruth, you are the only one who writes’.

It’s the same with teaching. We get to know so little of what effects we have on our students. But the internet offers a small measure of salvation. Sometimes a former student writes, ‘You don’t know me but I sat in your class in 1991 and…” It makes all the difference to get just one of those every few years, but it doesn’t add up to an objectification of the audience for our work.

I’ve had thousands of students and written one book. (In Chinese you are a “writer” if you’ve written one book and an “author” if you’ve written more than one — so I am a writer.) I don’t hear from my students very often but every day I get feedback from the SLD forums. To say I get “enough” feedback would be to understate the effect of comments like this:

I started a new job this past August . . . It’s so strange to be in a new place with people who’ve never known me as Fat Del. . . . That insidious “I wonder if there’s something wrong with her” has never crossed their minds. I’m just the normal girl in the next office. Men flirt with me and seem to think it’s cute when I’m not sure how to flirt back. . . . No one ever thinks I used to be fat and no one ever judges me in that light. Hell, my boss calls me by my full name and says it’s because Del is too short and casual for a pretty girl.

It’s so odd to be normal. I never thought I’d know what that was like.

Thanks for letting me know, Del.

Interesting Idea about Addiction

Saturday, September 29th, 2007

From addiction and self-experimentation:

I am coming to believe that [my] addiction may be caused by a specific kind of autism-related syndrome. I don’t crave order in everything that I do but I do crave order and structure in order for me to relate to others. I need to figure out some ways to get that structured social interaction that my brain requires. . . A 12-step meeting could be [seen] as just a highly structured social event.

A friend of mine became an Orthodox Jew in college; his parents were not very religious. Now and then I went to his house for Shabbat. As I got to know him better — outside the religious rituals — I was astonished at the difficulty he had carrying on a conversation. The many structures (rituals) of Orthodox Judaism made it much easier for him to spend time with other people.

The Wikipedia Wars

Saturday, September 29th, 2007

Speaking of Wikipedia, the LA Times has an interesting article today about what happened when Jimmy Wales — the founder — posted a one-sentence article about a butcher shop on the outskirts of Cape Town. It was deleted quickly — not important enough — but then a big debate ensued. The Times piece turned to the bigger issue:

Perhaps the granddaddy of all the Wikipedia debates is the question of which information deserves to be included, and which doesn’t. So-called Inclusionists believe that because Wikipedia is not bound by the same physical limits as a paper encyclopedia, it shouldn’t have the same conceptual limits either. If there’s room for an article on unreleased Kylie Minogue singles — and a group of people who might find it useful — why not include it? Deletionists, meanwhile, believe that because not all articles are created equal, judicious pruning increases the overall quality of Wikipedia’s information and strengthens its reputation. An encyclopedia, they say, is not just a dumping ground for facts.

While the people who run craigslist try hard to figure out what users want and how to give it to them — starting with the assumption that they themselves do not know — the people who run Wikipedia play God, at least by comparison. In this debate, both sides are playing God. As Aaron Swartz said, it isn’t wise. Jane Jacobs tells a story about a Pennsylvania Girl Scout troop. They were snobs; they made it hard for new members to join (the Wikipedian attitude that Aaron criticized). The girls who couldn’t get in formed their own troop. Several years later the new troop was thriving; the old troop was dying.

Deeper Voice = More Children?

Saturday, September 29th, 2007

At Language Log, Mark Liberman has an excellent discussion of a new paper that reports a correlation between voice pitch and number of children for men in a hunter-gatherer population. Men with deeper voices had more children. This portion of Liberman’s post surprised me:

This particular form of sexual dimorphism is apparently not shared with our relatives the chimps and gorillas, so it must have evolved during the same period that human speech and language did. Therefore, starting at some point during the last five million years or so, there must have been a selective advantage for male hominins with lower voices. And according to the featured study (C.L. Apicella, D.R. Feinberg, F.W. Marlowe, “Voice pitch predicts reproductive success in male hunter-gatherers”, Biology Letters, published online 9/25/2007), evidence of this selective advantage can still be found today.

I agree with all of this. The puzzle is that the effect remains. Five million years is a long time; shouldn’t the dimorphism have gotten larger and larger until an equilibrium was reached, and then stayed at that equilibrium? Once equilibrium is reached it will be the average voice pitch that is most successful.

I can think of several possible answers.

1. The correlation is due to random variation. Because lots of surveys have shown that women prefer men with deeper voices, this is less plausible.

2. Evolution is still happening on this dimension. That is, equilibrium hasn’t yet been reached.

3. This particular tribe was pushed away from equilibrium for an extended time — that is, for a long time higher-pitched men’s voices were more advantageous than usual. Whatever caused that has disappeared so this group is moving back toward equilibrium.

4. It’s about signalling. The voice-pitch variation observed in populations is mostly due not to genetic variation but to early environment (say, testosterone in the womb) and is correlated with something less visible that makes a difference in the reproductive success of one’s children.

I imagine the authors of the paper favor #4. When the full text is available for free, I’ll find out and post again.

Support for the Theory Behind SLD

Friday, September 28th, 2007

On the SLD forums, a member named Del posted this:

Roughly a month ago, I got tired of the oil. I was fighting to take it and something about one of them was causing an allergic reaction (dermatitis), so I switched to noseclipped oatmeal with brown rice protein. I haven’t noticed any change in my appetite suppression (read, still ridiculously good) and my weight loss has maintained at the usual rate of 3lbs or so per week. I’m really enjoying it and I have that nice full feeling as well.

So in the interest of sharing, that’s:
1/2 c. quick cook oatmeal
2T. brown rice or egg white protein
1 c of water
Cook in microwave for 2 minutes, let sit for one minute. Consume noseclipped morning and night.

In conventional nutritional terms, oil and the oatmeal mixture are very different. One is all fat, the other has almost no fat. Yet they have had the same effect on her weight. The theory behind the Shangri-La Diet predicts this but few if any other theories do. For example, if you believe in low-carb diets, you would predict that the oil (no carbs) would cause weight loss more easily than the oatmeal mixture (which has plenty of carbs).

Aaron Swartz on What’s Wrong with Wikipedia

Friday, September 28th, 2007

I recently asked Aaron Swartz, who has written about Wikipedia and run for its board of directors, what he thought was wrong with it. Three big things, he said:

1. Failure to value new contributors. A small number of insiders are dismissive of and treat poorly newcomers who contribute. For example, their contributions are deleted without explanation. The insiders see the newcomers as a source of trouble rather than strength.

2. Disorganized and underfunded. It took someone Aaron knows two years to make a deal with Wikipedia. The finances are in bad shape.

3. Lack of vision. Wikipedia could be improved in many ways but actual improvements are rare.

He used to see Wikipedia as just a wonderful thing, he said; now he sees it as a wonderful thing that is falling way short of what it could be.

You seem to be saying someone could come along and start a better open-source encyclopedia, I said. That’s unlikely, he said, Wikipedia is so big.

Who does it better? A similar but vastly better-run website is craigslist, he said. A chart of page view rank and number of employees shows Yahoo at #1 with 10,000 employees, TimeWarner at #2 with 90,000, Google at #3 with 10,000, and so on. Craigslist is #7 with 23 employees.

Addendum: Wikipedia, with very few employees, would of course also rank very high on such a chart; this is the magic of both Wikipedia and craigslist and why it makes sense to compare them. The craigslist link I gave, to a Wall Street Journal article, suggests that craigslist values contributors much more than Wikipedia. Here is what happened at a Wikipedia board of directors meeting that Aaron attended a few years ago:

One presentation was by a usability expert who told us about a study done on how hard people found it to add a photo to a Wikipedia page. The discussion after the presentation turned into a debate over whether Wikipedia should be easy to to use. Some suggested that confused users should just add their contributions in the wrong way and a more experienced users would come along to clean their contributions up. Others questioned whether confused users should be allowed to edit the site at all — were their contributions even valuable?

Columbia University President Lee Bollinger’s Surprising View of Freedom of Speech

Thursday, September 27th, 2007

On issues I care about, college presidents have a terrible record. After Margot O’Toole accused Imanishi-Kari of scientific misconduct, David Baltimore — later president of Rockefeller University and Caltech — stood by as O’Toole’s career was ruined. Both O’Toole and Imanishi-Kari were in Baltimore’s lab. I’m sure O’Toole was right; ink and digit analyses made it clear that Imanishi-Kari’s data was fake. The current Chancellor of UC Berkeley, Robert Birgeneau, when he was head of the University of Toronto, stood by as a job offer to the psychiatrist David Healy was withdrawn because Healy had criticized drug companies. President of Reed College Colin Diver failed to grasp that what he strongly objected being done to him was what Reed professors did to their students every day. Axel Meisen, President of Memorial University, has allowed his university’s lawyers to defend the indefensible: Memorial failed to protect the nurse who tried to stop Ranjit Chandra. Henry Bienen, President of Northwestern University, allowed Lynn Conway and Deidre McCloskey to use the power of his university to punish Michael Bailey for saying something that Conway and McCloskey didn’t like.

I might have given Columbia University President Lee Bollinger credit for supporting free speech when the President of Iran spoke there a few days ago. But I won’t, because here is how Bollinger introduced him:

[long self-congratulation] . . . Let me now turn to Mr. Ahmadinejad. . . [long no-stone-unturned condemnation] . . . Mr. President, you exhibit all the signs of a petty and cruel dictator. . . . Why are you so afraid of Iranian citizens expressing their opinions for change? . . . You held a two-day conference of Holocaust deniers. For the illiterate and ignorant, this is dangerous propaganda. . . . When you have come to a place like this, this makes you, quite simply, ridiculous. You are either brazenly provocative or astonishingly uneducated. . . . Because of this, and for many other reasons, your absurd comments . . . I close with this comment frankly and in all candor, Mr. President. I doubt that you will have the intellectual courage to answer these questions. . . . your preposterous and belligerent statements . . . so embarrassed sensible Iranian citizens . . . I am only a professor, who is also a university president.

Ugh. Ahmadinejad objected:

In Iran, tradition requires that when we demand a person . . . to be a speaker, we actually respect [the audience] by allowing them to make their own judgment, and we don’t think it’s necessary before the speech is even given . . . to provide vaccination.

Bollinger did not understand that freedom of speech means nothing unless you listen to those allowed to speak.

Addendum: Bollinger, a former Law School professor, teaches a class on freedom of speech. At the next meeting of this class, shortly after the remarks I quote above, “the students erupted in cheers.”