Category: Science

It’s a mad, mad, mad, mad cow world

The market is often accused of under-providing safety. Consider, however, that the Department of Agriculture is refusing to let a Kansas beef producer test its cattle for mad cow disease. Yes, you read that right. The producer, Creekstone Farms, is losing $40,000 a day because it exports its beef to Japan where such tests are required. The testing of individual cattle, however, runs contrary to the DOA/industry message that American beef is perfectly safe without expensive testing.

The mad cow case is a clear example of regulatory capture. By the way, the DOA aquired its power to decide minimum and maximum testing standards test under the Virus Serum Toxin Act of 1913 – it was captured a long time ago.

Don’t be surprised if the DOA requires such testing in the near future. I am reminded of the similar folic acid story that I wrote about with Dan Klein at

In 1992, the federal Centers for Disease Control and Prevention (CDC) recommended that women of childbearing age take folic acid supplements. Studies showed that taking folic acid reduced risks of babies suffering neural-tube birth defects such as anencephaly and spina bifida. The FDA immediately announced, however, that it would prosecute any food or vitamin manufacturer that placed the CDC recommendation in its advertising or product labeling (Calfee 1997). The public did not learn of the importance of folic acid until Congress passed the Dietary Supplement Health and Education Act of 1994, which loosened the FDA’s vise on the advertising of vitamins and other dietary supplements. Within only a few years of its ban on publicizing the CDC recommendation, the FDA made a complete turnabout. Since 1998, the agency has required manufacturers to fortify a variety of grain products with folic acid–that which is not prohibited is mandatory.

New punishment for speeders

In a move unprecedented in the Bay Area, the city’s traffic engineers have created a traffic signal with attitude. It senses when a speeder is approaching and metes out swift punishment.

It doesn’t write a ticket. It immediately turns from green to yellow to red.

Here is the full story, thanks to the ever-vigilant

My take: This will succeed in reducing speeding. By making the decision calculus more uni-dimensional (time vs. time, rather than time vs. speeding ticket), individiuals are more likely to see the folly of driving at unsafe speeds.

Here is a general introduction to framing effects. Here is a short article about framing effects in Alice in Wonderland. Here is Daniel Davies on how framing effects matter.

But what about civil liberties? One commentator opined: “It’s depriving you of another one of your liberties — going fast”.

Addendum: Tim Worstall writes in:

“The anti speeder traffic light ?
Been around for years.
Here in Portugal they’re all over the place.
And they work very well, just as advertised.”

The world’s highest suicide rate

The highest suicide rate in the world has been reported among young women in South India by a new study. The research is of major importance, according to the World Health Organization, as it brings to light Asia’s suicide problem.

The average suicide rate for young women aged between 15 to 19 living around Vellore in Tamil Nadu was 148 per 100,000. This compares to just 2.1 suicides per 100,000 in the same group in the UK.

The global suicide rate stands at 14.5 deaths per 100,000, with suicide the fourth leading cause of death in the 15 to 19 age group. However, in the Tamil Nadu study, suicide was the number one cause of death among these adolescents.

Notably, young women were much more likely to kill themselves than young men – the reverse of the rest of the world. In Western countries, men are three times more likely to commit suicide than women.

Here is the full story. Here is an NBER paper on the determinants of teenage suicide in the United States. Earlier Alex wrote about suicide as a social phenomena involving tipping and multiple equilibria.


Freeman Dyson introduces us to Littlewood’s Law of Miracles:

Littlewood was a famous mathematician who was teaching at Cambridge University when I was a student. Being a professional mathematician, he defined miracles precisely before stating his law about them. He defined a miracle as an event that has special significance when it occurs, but occurs with a probability of one in a million. This definition agrees with our common-sense understanding of the word “miracle.”

Littlewood’s Law of Miracles states that in the course of any normal person’s life, miracles happen at a rate of roughly one per month. The proof of the law is simple. During the time that we are awake and actively engaged in living our lives, roughly for eight hours each day, we see and hear things happening at a rate of about one per second. So the total number of events that happen to us is about thirty thousand per day, or about a million per month. With few exceptions, these events are not miracles because they are insignificant. The chance of a miracle is about one per million events. Therefore we should expect about one miracle to happen, on the average, every month. Broch [co-author of the book Dyson is reviewing] tells stories of some amazing coincidences that happened to him and his friends, all of them easily explained as consequences of Littlewood’s Law.

The law echoes a comment I’ve seen attributed to another mathematician, Persi Diaconis. Diaconis supposedly said that if you study a large enough population over a long enough time period, then “any damn thing can happen.”

Brood X is coming

Washington is preparing for an invasion. Several weeks from now billions and billions of insects will ascend upon the city from their hiding places under the ground to be begin two weeks or so of frenzied sex followed by egg-laying and dying. I know what your thinking – there goes Tabarrok again with his apocalyptic visions of doom and gloom.

The invaders, however, are not the biblical locusts of old but cicadas and they are going to be sex-starved because they only do this every 17 years. Why 17? No one knows for sure but 17 is prime so to meet the cicadas every time they appear a predator must lock-on to the exact frequency (while if they appeared say every 12 years then predators appearing every 2,3,4,6, or 12 years would be sure to meet them). There is another variant of periodical cicada that appears every 13 years, supporting the prime theory.

The cicadas are loud and the WashPost notes that the 1970 appearance of brood X inspired Bob Dylan to pen these lines:

And the locusts sang, well, it give me a chill,

Yeah, the locusts sang such a sweet melody.

And the locusts sang with a high whinin’ trill,

Yeah, the locusts sang and they was singing for me . . .

Addendum: Thanks to Marc Poitras for correcting me on one point. The cicadas can get plenty to eat underground so they really are coming out for the sex. Makes sense to me.

Evolutionary theories I don’t believe

In their paper titled “Love’s Labour Lost,” recently submitted to a medical journal, anthropologist Edward Hagen, biologist Paul Watson and psychiatrist Andy Thomson suggest that full-blown major depression disorder may be a complex social adaptation originating in the human evolutionary past and designed to help otherwise powerless individuals influence their social groups, focus on problem-solving and obtain help from those with whom one is in conflict.

“Depression evolved to compel assistance from reluctant social partners,” they theorize. “Depression signals need and compels social assistance by preventing the sufferer from providing benefits to others.”

They cite the severe cost of depression not only to the individual but to the whole social network.

“The toll depression takes on both its victims and society may be precisely what it was, in human evolutionary history, designed to do.”

This thinking – that depression is an important signal and part of a complex dynamic among people that provokes change – leads these researchers to argue that drug therapy alone for depression may not be the best solution even it relieves symptoms.

It may be that non-chronic major depressive disorder (MDD) is like fever – a signal that something has gone awry and needs to be healed.

Here is the full story. Here is a link to the relevant research. Here is the specific piece in question. Here is a related piece, called “Depression as Bargaining”. For a good time try using that description on your girlfriend.

Why I am skeptical: I can see why emotional sensitivity to bad events has survival value. Emotions bring general benefits, plus the sensitivity keeps you away from bad events to some degree. It is harder for me to see a great importance for the negative reaction itself, ex post, once bad events have happened.

Build a house in 24 hours

Randall Parker cites the following link:

Degussa AG, one of the world’s largest manufacturers and suppliers of construction materials, will collaborate in the development of a USC computer-controlled system designed to automatically “print out” full-size houses in hours.

Funded by a grant from the National Science Foundation, Behrokh Khoshnevis of the USC Viterbi School of Engineering’s Information Sciences Institute has been developing his automated house-building process, called “Contour Crafting,” for more than a year.

Khoshnevis believes his system will be able to construct a full-size, 2,000- square-foot house with utilities embedded in 24 hours. He now has a working machine that can build full-scale walls and is hoping to actually construct his first house in early 2005.

Contour Crafting uses crane- or gantry-mounted nozzles, from which building material – concrete, in the prototype now operating in his laboratory – comes out at a constant rate.

Moveable trowels surrounding the nozzle mold the concrete into the desired shape, as the nozzle moves over the work.

Parker adds:

Robots and other automated equipment have increased factory automation so much that factories are a dwinding source of all jobs. The next big target for automation has been and continues to be office work. Office automation is being addressed with the development of huge amounts of software and information systems.

What never seem to get as much attention is how to automate all the other places where people work aside from the office and the factory. Construction automation is an obvious big target. One approach is to do prefabrication of walls and other building pieces in highly automated factories. Then the prefabricated parts can be shipped to the construction site. But automated methods to doing construction at a site have advantages because they avoid the difficulty of shipping large walls, floors, and ceilings to a site. Also, automated site construction techniques allow more flexibility in site design.

My take: In economics language, this is called “g>r”, which refers to the growth rate of an economy exceeding its rate of interest. If we’re going to make it through our forthcoming fiscal crises, it will be through innovations such as these.

Water on Mars

Maybe there was once water on Mars. Maybe not. Reuters reports:

“We think Opportunity is now parked on what was once the shoreline of a salty sea on Mars,” said Steve Squyres, principal investigator for the science payload on Opportunity and its twin Mars exploration Rover, Spirit.

On March 2, astronomers announced that the Red Planet was “drenched with water” at some point. But the rovers’ analysis of Mars rocks has now produced the first concrete evidence that liquid water might actually have flowed on planet’s surface.

“If you have an interest in searching for fossils on Mars, this is the first place to go,” said Ed Weiler, NASA’s associate administrator for space science.

Love that alliteration–the shoreline of a salty sea. It conjures up images of beachcombers and cottages or at least seashells and seaweed with terns turning in the sunlight. Seems like a bit of a stretch. NASA thinks they’ve found not just moisture, not just a few molecules of H2O but a sea with rocks drenched with salty spray, rocks lovingly shaped by streaming water. Pardon my skepticism, but it seems that NASA has just a bit of interest in stretching the results. Notice that even Reuters uses the word “might.”

This hasn’t dampened any of the enthusiasm. Here’s one analysis headlined “Mars water discoveries loom huge” that compares the finding to Galileo’s discoveries.

…the sheer disclosure of the presence of water on a planet other than our own is monumental. It ranks with the moment, nearly 400 years ago, when Galileo Galilei peered through his telescope and discovered spots on the sun, mountains on the moon and four tiny bodies circling Jupiter.

Those revelations, which today are taken for granted, also were monumental in their day. Prior to their disclosure, people confidently — even fervently — believed Earth was the immovable center of the universe, surrounded by all the heavenly bodies, each of which was a perfect, featureless sphere. Galileo’s announcement was considered so shocking at the time he was charged with heresy by the Roman Catholic Church.

Opportunity’s findings have been treated more matter of factly, with NASA officials holding a news conference and bubbling over with enthusiasm at the images Opportunity has transmitted, and members of the media duly reporting the information and displaying the rover’s images.

Yet the importance of this finding cannot be overstated.

Until now, we have known for sure of only one planet on which liquid water has flowed — and water is absolutely essential for supporting life as we know it. There are no chemical processes that will permit the formation of the long, complex organic molecules composing living organisms other than in the presence of water.

It is an extremely simple rule: No water, no life. As long as Earth was the only planetary body containing liquid water — and, more particularly, seawater — then it was the only place in the universe where life was possible.

Now, suddenly, there are two.

Is this a huge discovery? Huge for NASA, certainly, eager to send people to Mars in search of fossils or at least an abandoned sailboat.

I’m in the middle of Simon Morris’s Life’s Solutions: Inevitable Humans in a Lonely Universe. I suspect Morris is unimpressed with the latest Martian chronicle. He argues that it is very likely that we’re alone in the universe. The first part of the book that makes this claim is fascinating with quirky writing and lots of good information. The rest of the book argues for the inevitability of humanity evolving. The writing and narrative of the second half is less spritely and slower going but the first part of the book is very much worth a look.

The origins of human intelligence?

Researchers have proposed an answer to the vexing question of how the human brain grew so big. We may owe our superior intelligence to weak jaw muscles, they suggest.

A mutation 2.4 million years ago could have left us unable to produce one of the main proteins in primate jaw muscles, the team reports in this week’s Nature. Lacking the constraints of a bulky chewing apparatus, the human skull may have been free to grow, the researchers say.

The timing of the mutation is consistent with rampant brain growth seen in human fossils from around 2 million years ago, says Nancy Minugh-Purvis of the University of Pennsylvania in Philadelphia, who helped with the study. “Right at the point you lose power in these muscles, brain size evolution accelerates,” she says.

Here is the full story. Here is the original research. Here is another account, which also reports on the critics of the idea. My gut level lay person’s response is not to believe the hypothesis, but hey, try convincing a physicist of the notion of comparative advantage.

Small families can decrease social mobility

…it is among larger families that the household or kin effects on the success of children are the weakest. Not only do children from larger families do worse on average than those from smaller families, but they also experience more randomness. In other words, parents’ class status affects their offspring more weakly in large families than in small ones. Likewise, siblings resemble one another less in larger families. For example, sibling similarity in income levels is approximately 24 percent stronger in families with three siblings or fewer than in families with four or more children. For net worth levels…the degree of sibling similarity is 59 percent greater in smaller families.

Those are significant effects, what will they mean?

What all this means for the class structure of American society is that as families get smaller, there may be less socioeconomic mobility, not more. Parents will be able to more carefully control the environments of their offspring and thereby reproduce their own class status.

There is a caveat:

Of course, this depends not just on the overall average number of kids that families are having, but also on the distribution. If the most dramatic declines in family size occur among the economically disadvantages segments of American society then we could have more equality of opportunity.

In other words, having larger families, across the board, will mean that subsequent income is less correlated with family history. But on average it will not raise the prospects of people from poor families.

From Dalton Conley’s excellent The Pecking Order: Which Siblings Succeed and Why. Follow this link and here for my earlier writings on Conley.

Born to Sue?

Frank Sulloway’s Born to Rebel (BTR) was a smash hit when it was published in 1996. Sulloway’s thesis, that laterborns are born to rebel while first-borns are conformist defenders of the status quo, was initially greeted with some skepticism among experts who knew of an earlier review of the large literature on birth order that had found little evidence for an effect on personality. The thesis struck a cord with the public, however, and Sulloway seemed to have gathered so much data from so many different sources (including scientific revolutions, political revolutions, religious revolutions etc.) that with a few exceptions (such as the great Judith Harris) the book won over skeptics and carried the day. Michael Shermer, Mr. Skepticism himself, said, for example, that Born to Rebel was “the most rigorously scientific work of history every written.”

Two devastating studies of BTR, however, have just now been published in the September 2000 issue of Politics and the Life Sciences (alas this issue is not online, perhaps for reasons discussed below). After exhaustive efforts, the studies failed to replicate key results in BTR – that is the authors tried to replicate what Sulloway said he did, on the data that he said he used and they could not reproduce anything close to his results. Now, you may be asking, how it is that the September 2000 issue of PLS has only now been published? And therein lies a story.

When Politics and the Life Sciences decided to publish the initial critique of BTR by Frederic Townsend, after peer review by four referees, it invited Sulloway to respond along with a number of others in a roundtable format that they had used in previous debates. Sulloway was guaranteed ample room to respond to Townsend and was invited to submit his own names for roundtable participants. He initially agreed but shortly thereafter he wrote to Gary Johnson, the editor of the journal, threatening that if the critique were published he would sue both the journal and the editor personally for what he considered to be defamation. Even if the Townsend article were thoroughly revised he insisted to the editor that it would be “appropriate – indeed legally mandatory – for you to preface his article with an editorial forewarning that reads more or less as follows”:

It is not normally the policy of this journal to publish data that are known, in advance, to be actually or potentially in error, especially when such data are being used in an attack on another scholar. However, as editor of this journal, I have decided…to publish these erroneous data in their present form. Readers are warned, however, that none of Townsend’s empirical claims, or the conclusions based upon them, can be trusted with any degree of certainty. Townsend has also made other blatant errors of fact and interpretation that are now known to the editor and that seriously affect the credibility of this paper….

Of course, the editor refused this absurd request. Sulloway later wrote to the president of the editor’s university (with copies to the chair of the Board of Trustees and the university’s legal counsel), saying:

…I intend to file charges of misconduct against one of your faculty members, Gary R. Johnson….these allegations include, but are not necessarily limited to: defamation/libel, false light invasion of privacy, fraud, promissory estoppel, and breach of fiduciary duty…I will also be blowing the whistle by filing formal charges of scientific misconduct against Gary Johnson with the American Political Science Association, the Human Behavior and Evolution Society, members of Congress who have shown a concern about science fraud, and all other professional organizations with which Professor Johnson or his journal….are affiliated.

Bear in mind that Johnson is only the editor of the journal and not even the primary critic! Naturally, Sulloway’s threats delayed publication of the journal, as more referees were involved and revisions took place, but the worst was yet to come. The journal’s publisher refused to publish the debate unless the parties involved committed not to sue him, his printer, his distributor, the journal, or the association. Of course, Sulloway refused. The heroic Johnson and the association then decided to publish the journal on their own. As a result, the final publication, including Sulloway’s response, is nearly five years late.

All of this, and there is much more that I have not reported, is from Johnson’s shocking editorial explaining the long delay. Perhaps the most disturbing aspect of the whole ordeal is that our legal system, sometimes described as Russian Roulette, has gotten sufficiently capricious and arbitrary that Sulloway’s abusive legal threats were nearly successful. Johnson writes:

The virtual terror that Sulloway’s legal threats have prompted in some of those associated – directly or indirectly – with the events described in this editorial suggests to me that contemporary science must adapt to a changed socio-legal environment if the capacity for open dialogue and critical exchange that is the lifeblood of science and scholarship is to be protected. Scholars, scientists, and publishers cannot focus properly on what should be their principal concerns if the threat of catastrophic legal costs hangs over them and their organizations and journals.

Smart prostitute with heart of gold

Earlier Tyler reported that lying is more common over the phone than with email. Further evidence comes from a surprising source. In a letter to New Scientist magazine Yvette Astre writes:

I have found a similar difference between phones and email in my business.

I am a prostitute, and to get clients I advertise in the local newspaper. Normal practice is to provide a phone number as an initial point of contact. Using my cellphone was getting rather expensive, as was advertising several days a week. I also work as a volunteer for several non-profit community organisations, and there I found many people preferred emails to the phone or postal services. So I decided to try an email address instead.

The difference really surprised me. With my phone number, guys would sometimes make bookings then not turn up. Others sounded very creepy. However, using email I have had only two cancellations, and in both cases I was paid in full for the time they booked with me.

Then again, prostitutes who read New Scientist and volunteer at non-profits? Johns who pay for services not rendered? Was this letter phoned in or emailed?

What do we know about the children of gay parents?

Not much, according to this incisive article on “The existing science is methodologically flawed and ideologically skewed.”

Here is another major point:

…the defensive goal of proving sameness is almost a guarantee of weak science. (The hypothesis that both groups of kids are alike is hard to rule out, but that doesn’t mean you’ve established that there are no differences.) That “heterosexist” bias, Stacey argues, has also encouraged researchers to fudge results, anxiously claiming homogeneity where there’s actually some variety. Why, she asks, buy into the view that “differences indicate deficits”?

And consider the following:

Digging around in the existing data on kids of gay parents leads the authors and others to similarly rosy speculations that these children are unusually open-minded. Some studies, for example, show boys playing less aggressively and behaving more “chastely” as youths, while girls’ early interests are more androgynous and their adolescence evidently somewhat more sexually adventurous. On the hot topic of sexual orientation, the only long-term study of lesbian-headed families reports 64 percent of the young adult children saying they’ve considered same-sex relationships (compared to 17 percent with heterosexual parents)–although the percentage of those who identify themselves as gay, lesbian, or bisexual is the same in both groups.

Here is a survey of some reader reactions.

The bottom line: We need some good labor economists, or demographers, to tackle this problem. That being said, the policy-relevant comparison is not “gay parents” vs. “straight parents.” Rather it is gay parents vs. an orphanage, or gay parents vs. not having been born in the first place. I’ll put my money on the gay parents.

Are bubbles good for economic development?

Fools rush in, but should we mind?

…when it comes to transformative technologies, overoptimistic investors are actually working for the common good–even if they don’t know it. We can be glad that investors financed the construction of thousands of miles of track in the middle of the nineteenth century, despite the fact that most of them dropped a bundle doing it. The same goes for overoptimistic investors who poured money into semiconductors thirty years ago, financed undersea fibre-optic cables in the late nineties, and now are poised to lose their shirts in the coming nanobubble. In the dreams of avarice lie the hopes of progress.

The full story concerns the nanotechnology bubble, by the ever-intelligent James Surowiecki, writing for The New Yorker.

My take: The real story of the invisible hand is that many of the rewards offered by the capitalist system are illusory in value. Ayn Rand had a point that the world rests on the shoulders of the talented few. She forgot that those people often aren’t very rational.