Teachers Matter

From an interview with Judith Rich Harris:

LEHRER: You emphasize the importance of teachers in shaping a child's development. How can we apply this new theory of child development to public policy?

HARRIS: I’ve put together a lot of evidence showing that children learn at home how to behave at home (that’s where parents do have power!), and they learn outside the home how to behave outside the home. So if you want to improve the way children behave in school—for instance, by making them more diligent and less disruptive in the classroom—then improving their home environment is not the way to do it. What you need is a school-based intervention. That’s where teachers have power. A talented teacher can influence a whole group of kids.

The teacher’s biggest challenge is to keep this group of kids from splitting up into two opposing factions: one pro-school and pro-learning, the other anti-school and anti-learning. When that happens, the differences between the groups widen: the pro-school group does well, but the anti-school group falls further and further behind. A classroom with 40 kids is more likely to split up into opposing groups than one with 20, which may explain why students tend to do better in smaller classes. But regardless of class size, some teachers have a knack for keeping their classrooms united. Teachers in Asian countries seem to be better at this than Americans, and I suspect this is one of the reasons why Asian kids learn more in school. No doubt there’s a difference in cultures, but maybe we could study how they do it and apply their methods here.

The tendency of kids to split up spontaneously into subgroups also explains the uneven success rate of programs that put children from disadvantaged homes into private or parochial schools. The success of these programs hinges on numbers. If a classroom contains one or two kids who come from a different background, they assimilate and take on the behaviors and attitudes of the others. But if there are five or six, they form a group of their own and retain the behaviors and attitudes they came in with.

Blacks More LIkely to Die of Cancer: Why?

It's astonishing that this study can be described without anyone even speculating about the crucial anti-cancer role of Vitamin D:

African Americans are less likely than whites to survive breast, prostate and ovarian cancer even when they receive equal treatment, according to a large study that offers provocative evidence that biological factors play a role in at least some racial disparities.

The first-of-its-kind study, involving nearly 20,000 cancer patients nationwide, found that the gap in survival between blacks and whites disappeared for lung, colon and several other cancers when they received identical care as part of federally funded clinical trials. But disparities persisted for prostate, breast and ovarian cancer, suggesting that other factors must be playing a role in the tendency of blacks to fare more poorly.

Here is a discussion of Vitamin D and prostate cancer; here's a discussion of Vitamin D and breast cancer; and here are links to over 100 studies on Vitamin D and cancer. And given that 97% of African Americans are deficient in Vitamin D, this seems a pretty key question to look at.

New Paper on Teaching Styles

Apparently lecture-style teaching is better than classes that focus on "problem solving":

Is Traditional Teaching Really All That Bad? A Within-Student Between-Subject Approach

Guido Schwerdt
CESifo (Center for Economic Studies and Ifo Institute for Economic Research); European University Institute - Economics Department (ECO)

Amelie C. Wuppermann
University of Munich

Lecture style teaching is often regarded as old-fashioned and connected with many disadvantages: Lectures fail to provide instructors with feedback about student learning and rest on the presumption that all students learn at the same pace. Moreover, students' attention wanes quickly during lectures and information tends to be forgotten quickly when students are passive. Finally, lectures emphasize learning by listening, which is a disadvantage for students who prefer other learning styles. Alternative instructional practices based on active and problem-oriented learning presumably do not suffer from these disadvantages. National standards (NCTM, 1991; National Research Council, 1996) consequently advocate engaging students more in hands-on learning activities and group work. Despite these recommendations traditional lecture and textbook methodologies continue to dominate science and mathematics instruction in US middle schools (Weiss, 1997). This raises the question whether the high share of total teaching time devoted to traditional lecture style presentations has a detrimental effect on overall student learning.

* * *

To study the effect of lecture style teaching, we construct the share of e®ective teaching time, that is time in class devoted to either lecture style presentation or in-class problem solving, using information on in-class time use provided by teachers in the 2003 wave of the Trends in International Math and Science Study (TIMSS) in US schools. Estimating a reduced form educational production function and exploiting between-subject variation to control for unobserved student traits, we find that the choice of teaching practices matters for student achievement. We find that a 10 percentage point shift from problem solving to lecture style presentation results in an increase in student achievement of about 1 percent of a standard deviation.

This result is highly robust. Consistent with other studies in this literature, we find no evidence for significant effects of commonly investigated observable teacher characteristics such as teaching certificates or teaching experience.

* * *
We therefore conclude that the high share of total teaching time devoted to traditional lecture style teaching in science and mathematics instruction in US middle schools has no detrimental effect on overall student learning. This finding implies that attempts to reduce the amount of traditional lecture style teaching in US middle schools have little potential for raising overall achievement levels.

Health News

In health news, statins cause muscle damage, and BMI is a bogus measure.

Catfish and Big Business

Many people seem to believe that regulation is something that big business hates, and that someone who opposes a particular regulation must be acting as a "stooge" for business interests.

That belief is more of a caricature than anything else. In 1971, Nobel economist George Stigler published a famous article: The Theory of Economic Regulation. Stigler argued that industry regulation, far from being oppressive to big business, is usually "acquired by the industry and is designed and operated primarily for its benefit."

How does this occur? Often what occurs is the industry demands that the state control who gets to enter the industry in the first place -- say, licensing laws (an egregious example would be laws requiring casket salesman to be licensed). As Stigler says, "every industry or occupation that has enough political power to utilize the state will seek to control entry," usually by trying to "retard the rate of growth of new firms."

The catfish industry is just the latest in many examples of this phenomenon. As the Associated Press reported on July 3, 2009:

It looks like catfish, it tastes like catfish, and it acts like catfish.

But to U.S. catfish farmers, the whiskered bottom-feeding fish from Vietnam is something else: a cheap variety that’s usurping the humble catfish’s place on Americans’ tables and threatening their livelihoods.

So after years of arguing that the Vietnamese fish isn’t catfish — and winning a federal law saying as much — U.S. farmers are trying to have it both ways. Under their latest lobbying strategy, they want the Vietnamese imports considered catfish so they will be covered by a new inspections regime they pushed through Congress last year.

* * *
The U.S. industry — mostly located in Mississippi, Alabama and Arkansas — has had a string of successes on Capitol Hill and in Southern legislatures.

Along with winning frequent federal aid, it pushed a labeling law through Congress in 2002 that forced the Vietnamese fish to be sold in the U.S. under unfamiliar names such as pangasius, basa or tra. A year later, it won an anti-dumping case authorizing tariffs of up to 64  percent on the Vietnamese fish.

* * *

The inspections requirement could be the U.S. producers’ silver bullet, stopping imports in their tracks. Applying to all catfish sold in the U.S., it would require Vietnam to establish a complicated inspection system and demonstrate that it is equivalent to U.S. inspections, a process that could take years.

Last year, the industry persuaded catfish-state lawmakers led by Sen. Thad Cochran, R-Miss., to slip the inspection requirement into the massive farm bill.

The crucial thing to notice is that these sorts of regulations always come with noble-sounding public purposes. After all, who could be against truth-in-labeling or rigorous inspections of fish quality? But the reality is that such regulations are often used as a tool to suppress competition.

On Michael Jackson

There is no one who more perfectly personifies the infantilization of American culture. His obsession with retaining the looks, voice, and attributes of a wide-eyed child is just an extreme version of the countless celebrities who have a string of plastic surgeries, stretching their faces tighter and tighter, in the vain hope of maintaining an image of perpetual youth.

John Roberts and Michael Jackson

I love the letters that John Roberts wrote while in the White House, urging President Reagan not to honor Michael Jackson. E.g.:

I hate to sound like one of Mr. Jackson’s records, constantly repeating the same refrain, but I recommend that we not approve this letter. Sometimes people need to be reminded of the obvious: whatever its status as a cultural phenomenon, the Jackson concert tour is a massive commercial undertaking. The tour will do quite well financially by coming to Washington, and there is no need for the President to applaud such enlightened self-interest. Frankly, I find the obsequious attitude of some members of the White House staff toward Mr. Jackson’s attendants, and the fawning posture they would have the President of the United States adopt, more than a little embarrassing.

It is also important to consider the precedent that would be set by such a letter. In today’s Post there were already reports that some youngsters were turning away from Mr. Jackson in favor of a newcomer who goes by the name “Prince,” and is apparently planning a Washington concert. Will he receive a Presidential letter? How will we decide which performers do and which do not?

Think what could have happened had Reagan gotten in the habit of congratulating popular musicians.

The Reality of School Funding

In debates about education, you constantly hear the refrain that poor districts get less money than rich districts.

Although it's possible to cherry-pick exceptions, that claim is false. Here's a quote from Eric Hanushek & Alfred Lindseth, "Schoolhouses, Courthouses, and Statehouses" (Princeton Univ. Press, 2009):

It remains a common misperception that school districts with large numbers of poor children have significantly less money per pupil spent on them than other districts. While that may have been true at points in the past, for the last decade or more school districts serving the most disadvantaged populations, on average, have more to spend on each student than more economically advantaged districts. As shown in figure 3.6, by 2004 the poorest districts -- those in the highest 20 percent of the poverty distribution . . . -- spent as much on average as the wealthiest 20 percent of districts, and significantly more than those districts in the middle three quintiles.

From the National Center for Education Statistics, here's a useful chart (click to enlarge):

Musical Trickery

This post is a fascinating peek into the world of musical fakery, i.e., famous singers who have to rely on technology to project an image of being a competent singer.

Summer Vacation

I largely agree with Conor Clarke's argument that schools ought to get rid of "summer vacation." As a matter of equity, kids from less well-off families tend to fall behind when they have months in a row with little intellectual stimulation. Perhaps more cynically, one of the major purposes of schooling (society might as well admit it) is to provide a place for parents to stash their kids while they work, and a 2 or 3 month vacation makes things difficult for parents.

Eliminating summer vacation doesn't necessarily mean lengthening the school year, though. You could have a similar amount of vacation time interspersed throughout the year. Shorter vacations wouldn't allow kids to forget everything, nor would they be quite as difficult for scrambling parents to handle.

I'd be somewhat surprised, however, if the teachers unions go for it. I still remember how hard it was when I finally got out of school, and actually had to get a year-round job (I had always worked during the summers, but at least it was a complete change that provided some variety to the year.) About the end of May, I'd find myself thinking, "Wait, why am I having to keep working at this same job? This is no fun. I should be getting at least a few weeks off, and then transitioning to something different."

I eventually got used to working year-round at the same job, of course, but most teachers and administrators have never really had the experience of doing the exact same thing 12 months a year. Most of them have had summer vacation for their entire lives -- in elementary school, middle school, high school, college, and then their jobs. And even if they're doing some kind of work over the summer (say, professional development classes), it's a change of pace from what they've been doing during the school year.

Shop Class as Soulcraft

There have been many gushing reviews of Matthew Crawford's new book Shop Class as Soulcraft: An Inquiry into the Value of Work (see, e.g., here or here), a book that I'm sure I'll enjoy, given how much I liked the author's original New Atlantis article when it came out in 2006.

And yet . . . my own grandfather was a farmer, and he most certainly didn't have the same attitude towards manual labor vs. office work. In fact, he always used to tell me, "Get an education so that you can work indoors." And Tom Smith has some good points in his post titled "Manual work as sucking very much."

Perhaps everyone is prone to the "grass is greener" phenomenon? Those who spend a lifetime sweating in the sun look with envy on people who get to work sitting down in the cool, while those who work in cubicles look with envy on people who actually get to make or do something that seems more tangible and real.

Alternatively, perhaps there is widespread misallocation of human capital. By accident of birth or circumstances, there are many people who end up in blue-collar jobs who would have been much happier in an office job; and conversely there are many people who, by accident of birth or circumstances, find themselves slaving away in an investment bank or consulting firm, but who would have been much happier as a landscaper or plumber.

News from the World of Science

1. Researchers found out that dogs who have been set up (wrongfully accused of misbehavior) are then seen by their owners as having a "guilty look." In other words, a dog's "guilty look" is really because of the owner's scolding, not because of any psychological feelings of guilt.

And yes, I know some dog owners who need to be reminded of the fact that their dogs are not experiencing human emotions all the time.

2. A lot of sleep-related research: Interrupted sleep contributes to gestational diabetes; sleep helps regulate emotions; too little or too much sleep is linked to being fat; staying up late is linked to lower college GPA; lack of sleep is linked to high blood pressure and risk of death.

All of this is further evidence for my point that it's really weird that some occupations have developed a cultish attachment to bragging about one's willingness to forego sleep. It's as if you were to brag about hitting your own head with a hammer.