Month: October 2006


She gets mad at me for things she dreams I do.

That is from Justin, via Sacramento.  A few weeks ago Alex and I were discussing whether a person should feel guilty about his or her dreams.  Or should enjoying one’s memories of others give grounds for jealousy?  How about building a machine which will simulate a version of you who dreams of having enjoyed particular memories?

Frankly, I don’t see any clear ground here.

Dr. Curry and the future of mankind

Dr Curry warns…in 10,000 years time humans may have paid a genetic price for relying on technology.

Spoiled by gadgets designed to meet their every need, they could come to resemble domesticated animals.

Social skills, such as communicating and interacting with others, could be lost, along with emotions such as love, sympathy, trust and respect.  People would become less able to care for others, or perform in teams.

Physically, they would start to appear more juvenile.  Chins would recede, as a result of having to chew less on processed food.

There could also be health problems caused by reliance on medicine, resulting in weak immune systems.  Preventing deaths would also help to preserve the genetic defects that cause cancer.

Dr. Curry also claims:

Further into the future, sexual selection – being choosy about one’s partner – was likely to create more and more genetic inequality, said Dr Curry.

Only his third paragraph — about less sociability — fits my basic model of future human evolution.  Genetic engineering aside, won’t greater choosiness favor physically fit partners?  And given the ease of birth control, I expect that people will come to love their children more, even though they will care less about everyone else.  Who needs allies for quality child care when per capita income is very high? 

Here is the full story.  Thanks to Jason Kottke for the pointer.

Finding the predictive geniuses

James Acevedo is a "genius," though he admits no one at the
elementary school in Ridgewood, N.J., where he teaches third grade,
knows it.

But the Web site where he competes nightly,, was so taken by his record at forecasting sporting events
that it included him last month in a newly compiled list of 30
super-achievers culled from about 100,000 members and began selling
their "genius picks" to the public.

The obvious critical rejoinder is that someone from the group has the lucky touch, but only for a while.

"I go with my gut," he said. "It doesn’t feel like I’m a genius."

James is reluctant to take his wisdom to Las Vegas.  Here is the story, and thanks to Robin Hanson for the pointer.

Pumping Neurons

So I’m in the local Best Buy and I see that the Nintendo DS has Brain Age on display, it tests your "brain age" with a series of mental exercises.  Heh, I’m up for a workout so I run the game which does things like show you the word blue but written in red and you are supposed to say the color (not the word).  The store is noisy, however, so the damn microphone isn’t picking up my answers.   It gives me a brain age of 95!  What the #$$!%!.  So I run the game again and this time I’m shouting into the machine, blue, red, no I said red damn it, green, green, green…  Well, I managed to get my brain age down some but by now people were looking at me real funny.

    Anyway, if you want to try some of these exercises you can now join an online gym and workout at home.  The Washington Post has a brief review of some of the sites including MyBrainTrainer, Happy-Neuron and Brain Builder.  Of course, you know my recommendation for the best website to improve your brain power.

France fact of the day

While falling birthrates threaten to undermine economies and social
stability across much of an aging Europe, French fertility rates are
increasing.  France now has the second-highest fertility rate in Europe
— 1.94 children born per woman, exceeded slightly by Ireland’s rate of
1.99.  The U.S. fertility rate is 2.01 children.

In addition to birth subsidies, cultural norms encourage women to both work and have kids.  Here is the story.

Mindless eating

The best diet is the one you don’t know you are on.

I am not surprised to read this:

When eating in group of four or eight, light eaters ate more, and heavy eaters ate less.

Those are both from Brian Wansink’s Mindless Eating: Why We Eat More Than We Think.

Here is a New York Times article about the book; it summarizes the book’s practical tips.  Never let yourself forget how much you are eating.  You might also use smaller bowls and wrap transparent candy containers in aluminum foil. 

Why hasn’t Mexico done better?

After all they have NAFTA and democracy, sort of.  Here are the thoughts of Brad DeLong.  I don’t disagree with Brad’s discussion, here are my ideas:

1. The North of Mexico would have done far better, if not for adjusting to brutal competition from China.  They are in fact coping better than most people had expected.

2. The North has in any case done remarkably well.  This implies that the main problems are not of policy per se.

3. Mexico has had a serious internal "immigration" problem, as it tries to digest massive migration from rural areas into urban areas.  Many of these migrants do not have the appropriate cultural capital to support Mexican economic growth.  But this problem will ease over time as the country becomes more integrated.

4. The costs of crime and corruption are significant.  These costs skyrocketed as Mexico became a prime route for cocaine transport to the United States.  Not everything we have done for (to) Mexico has been positive.

5. Mexico will undergo a demographic transition.  Rising population will soon cease to swallow up so many of the per capita the gains from rising total income.

6. The available data significantly understate the standard of living gains in rural Mexico.  Incomes go underreported, or unreported, and new commodities are being introduced all the time.

7. Policy matters less than we economists like to think.

Designing a statistics regime for selfish economists

As my colleague David Levy points out, the economics of economists is a much neglected topic.  But there is some action on the horizon:

The role that competition among scientists will have on researcher initiative bias was discussed by Tullock (1959) who argued that competition would counteract the version of publication bias that occurs when 20 researchers each use different data sets to run the 14 same experiment but when only the one significant result gets published.  Tullock argued that in this case the other 19 researchers would come forward and discuss their insignificant results.  The conclusion Tullock drew from this is that publication bias is more likely to occur in a situation where there is a single data and 20 possible explanatory variables.  In that case, there is no obvious refutation that could be published over the false positive.  The best that can be done is to publish articles emphasizing the number of potential explanatory variables in the data set (as in Sala-I-Martin, 1997) or the fragility of the results to alternative specifications (as in Levine and Renelt, 1992).

That is from a new paper by Ed Glaeser, highly recommended.  Hat tip to New Economist blog.

Does television viewing trigger autism?

Gregg Easterbrook says yes, citing this new study.  Here is part of the abstract:

…we empirically investigate the hypothesis that early childhood television viewing serves as such a trigger [for autism].  Using the Bureau of Labor Statistics’ American Time Use Survey, we first establish that the amount of television a young child watches is positively related to the amount of precipitation in the child’s community.  This suggests that, if television is a trigger for autism, then autism should be more prevalent in communities that receive substantial precipitation.  We then look at county-level autism data for three states – California, Oregon, and Washington – characterized by high precipitation variability.  Employing a variety of tests, we show that in each of the three states (and across all three states when pooled) there is substantial evidence that county autism rates are indeed positively related to county-wide levels of precipitation.  In our final set of tests we use California and Pennsylvania data on children born between 1972 and 1989 to show, again consistent with the television as trigger hypothesis, that county autism rates are also positively related to the percentage of households that subscribe to cable television.  Our precipitation tests indicate that just under forty percent of autism diagnoses in the three states studied is the result of television watching due to precipitation, while our cable tests indicate that approximately seventeen percent of the growth in autism in California and Pennsylvania during the 1970s and 1980s is due to the growth of cable television.  These findings are consistent with early childhood television viewing being an important trigger for autism.

I am unconvinced.  Precipitation, in these states, is a coastal phenomenon and is proxying for heterogeneity in the gene pool.  Perhaps the coastal areas attract a more "autism-ready" group of individuals.  In fairness to the authors, they do try to control for income and education and population density and diagnosis capacity, among other variables.  Note two worrying features in the results: in California precipitation is not correlated with autism rates at all (there is a north vs. south split for rain, rather than the coast vs. inland), and precipitation is a better predictor of autism than cable viewing is directly. 

Here is the latest autism news on the genetic front.

Addendum: Steve Levitt is also skeptical.