Category: Science

Nobel Prize for iPod

I think what is most interesting about today’s Nobel prize in physics is how quickly the discovery of a new effect, giant magneto-resistance, led to real devices including the iPod.  From the totally unknown to the utterly familiar in less than twenty years.  The world really is speeding up.

The Nobel Prize Foundation has a very nice write-up of giant magneto-resistance and its applications.

Inequality and unhappiness

What I found was that economic inequality doesn’t frustrate Americans at all.  It is, rather, the perceived lack of economic opportunity that makes us unhappy.  To focus our policies on inequality, instead of opportunity, is to make a grave error–one that will worsen the very problem we seek to solve and make us generally unhappier to boot.

Here is the full article, interesting throughout.  This paragraph is right on the mark:

One of the many problems with the egalitarians’ line of reasoning is that it misinterprets the experimental evidence.  The two famous studies mentioned above don’t necessarily mean, as the egalitarians claim, that people would be happier in a world of total equality.  Rather, they suggest that in a world of inequality, people like having more than others and dislike having less–even to the point of neglecting their financial interests.  How people would react to a miraculously equal world is something that the studies don’t attempt to address.

And this:

But there is another, more fundamental, reason that the arguments linking economic inequality to unhappiness are mistaken.  If the egalitarians are right, then average happiness levels should be falling.  But they aren’t.  The GSS shows that in 1972, 30 percent of the population said that they were “very happy” with their lives; in 1982, 31 percent; in 1993, 32 percent; in 2004, 31 percent.  In other words, no significant change in reported happiness occurred–even as income inequality increased by nearly half.  Happiness levels have certainly shown some fluctuations over the last three decades, but income inequality explains none of them.

Thanks to Michael Cragg for the pointer.  You might also revisit my earlier post on mobility.

Irrational beliefs I hold about carbon emissions

I have two sets of beliefs about global warming.  The first set I infer from the observed "scientific consensus," but applying my "sociology of science" adjustments to the filters of mainstream media, intelligent blogs, reports of peer-reviewed journals, popular science books, and so on.  That means somewhat more skepticism than the postulated consensus, but mostly I buy into the consensus account as our best available estimate.  Procedurally speaking, I am not sure how I could make these beliefs more rational.

The second segment of my beliefs is less rationally grounded.  I believe, for instance, that ocean acidification will, in the long run, be the most dangerous consequence of carbon emissions.  (And by saying that I don’t mean to downgrade the other worries.)

I am aware that this belief isn’t necessarily justified.  It is shared by some scientists as a speculation, and it could turn out to be true, but it is hardly well-grounded as our major worry even though it does seem to be a real worry. 

Still, for whatever reason, I cannot help but believe it, or at least believe it with some excess degree of credence.  Is this because I visited the ocean as a child, and received some mysterious emotional sense of its powers, a sense which I can no longer eradicate from my subconscious?  Or am I more generally attracted to explanations which postulate some deeper but slightly hidden or indirect problem with status quo policies?  (I could look for signs that I hold similar delusions elsewhere.)

I try to keep these beliefs from affecting my policy conclusions, but I am not altogether able to stop holding them.  And even if my belief turns out to be true (which I expect someone to suggest in the comments), I am quite sure my procedural reason for holding it is an irrational one.

Why Most Published Research Findings are False (2)

John Ioannidis’s argument that most published research findings are false has been getting some attention in the blogosphere because of a recent article in the WSJ.  In an earlier post I  explained why most published research findings might be false using a simple diagram.

Hat tip and thanks to Steve Novella at Neurologica Blog and Mark H at Denialism both of whom refer to my analysis adding many excellent insights of their own.

What is Intelligence?: Beyond the Flynn Effect

That is the new book by James R. Flynn.  He suggests the following:

Today we have no difficulty freeing logic from concrete referents and reasoning about purely hypothetical situations.  People were not always thus.

In other words, people in earlier times really were stupider when it came to abstract thought, but this was primarily for environmental reasons.  These people also had more daily, practical skills, again for reasons of practice.  We in contrast receive daily workouts with hypotheticals, rapidly moving images, and spatial reasoning.  So Flynn is suggesting that IQ isn’t more multi-dimensional than it may seem.  The Flynn Effect gains are in fact concentrated in the most spatial and abstract versions of IQ tests.

Flynn summarizes the "Dickens-Flynn" model, through which environment and IQ interact in multiplicative fashion.  Smart people seek out environments which make them even smarter, and this helps reconcile the cross-sectional IQ data (adoption doesn’t change IQ so much) with the time series of increasingly higher IQ scores (environments are changing for everybody).  This reconciliation was fuzzy to me, but I took Flynn to be claiming that separated identical twins will reimpose common environmental forces on themselves, thus keeping their IQs in relatively close long-run synch.  I still don’t understand what kind of test (might it contrast permanent vs. temporary environmental shocks?) might falsify the Dickens-Flynn model.

Flynn also argues that the Chinese in America attained high levels of achievement before
above-average IQs.

This book doesn’t tie up all the loose ends, and it could have been written in a more organized fashion.  Still it is one of the more interesting volumes of the year.

Addendum: I have long thought that the Germanic "Hausmusik" tradition was responsible for producing so many great composers in one relatively short period of time.  Flynn’s book offers (unintended) hints about why it is so hard to reproduce the cultural blossomings of times past, and also why future creations will seem baffling to the old fogies.

Dogs can, monkeys and wolves can’t

The researchers held two containers, one empty and the other
containing food, in front of chimpanzees and dogs. Then they pointed to
the correct container. The canines understood the gesture immediately,
while the apes, genetically much more closely related to humans, were
often perplexed by the pointing finger.

That’s not all. Many dogs were even capable of interpreting the
researcher’s gaze. When the scientists looked at a container, the dogs
would search inside for food, but when they looked in the direction of
the container but focused on a point above it on the wall, the dogs
were able to understand that this was not meant as a sign.

Puppies seem able to do this before they have been socialized with human beings.

Says one researcher: "The great advantage of dogs is that we can study them in their
natural habitat without any great effort," explains Adám Miklósi.

Here is the full story, hat tip to Mark Thoma.

Cool It, by Bjorn Lomborg

That’s Bjorn Lomborg’s latest book on global warming.  He has good arguments against the exaggerations of others, so this book is worth reading.  I cannot, however, agree with one of his central claims, namely that the most serious economic research favors only mild remedies or sees the problem as only a moderate one.   

I would instead claim the following:

1. Policy recommendations are extremely sensitive to the choice of discount rate, and economists do not agree on this issue.  Furthermore most economists do not even know enough moral philosophy to understand the issues involved (and the philosophers don’t understand enough economics), so there is no coherent consensus one way or the other.

2. The most current economists’ word is from Martin Weitzman; he argues that the very high costs of the worst-case scenarios suggest an insurance-based case for significant worry, more worry than Lomborg suggests.  A Salon review notes:

Harvard’s Weitzman puts the current concerns of many economists
clearly. Based on the findings of the U.N. climate panel, he notes that
with roughly 3 percent probability, "we will [live in] a terra
incognita biosphere within a hundred years whose mass species
extinctions, radical alterations of natural environments, and other
extreme outdoor consequences of a different planet will have been
triggered by a geologically-instantaneous temperature change that is
significantly larger than what separates us now from past ice ages."

3. We spend too much time wondering about what is "most believable" and not enough energy worrying about the expected value of pending losses.  The major critical reviews all nail Lomborg for neglecting this point.  That said, the speed with which the negative reviews of the book move to the extreme cases is itself noteworthy, and it does not exactly correspond to the image presented to the public.

4. Given that the value of risk is context-specific, economists are bad at taking the value of insurance from market data in one setting, and then transplanting that estimate to another setting.

5. The strongest argument against significant action is not from cost-benefit analysis in the narrow sense, but simply that we are not very good at producing international public goods.  Especially when it comes to extended, intertemporal collective action problems directed against small probability events, with unclear periodic feedback, and dealing with the Chinese and the Indians, who feel they have the right to pollute as much as we did, and also with the not-nearly-as-cooperative-as-they-might-sound Europeans (how’s that sentence for a mouthful?). 

This argument sounds immoral and indeed perhaps is immoral — "we’re ruining things for others, yet if we tried to fix things we would ruin the fixing, so let’s do nothing."  Yet I do not think this issue should be disregarded.  If I can’t open up my computer, dissemble it, and then put it back together again, surely my repair plans should take that fact into account.

Here is a Jonathan Adler review of the book.  Here is a very critical Tim Flannery review.  Here are critical remarks from Chris Mooney.  Here is the Salon review.

Remember that line from Dirty Harry?:  "Do you feel lucky, kid?"

Space Tourism II

Three years ago I wrote a controversial article, Is Space Tourism Ready for Takeoff?, in which I argued:

The vision is enticing but the facts suggest that space tourism is not
ready for market. The problem is not the monetary expense, there are
enough millionaires with a yearning for adventure to support an
industry. The problem is safety. Simply put, rockets remain among the least safe means of transportation ever
invented. Since 1980 the United States has launched some 440 orbital
launch rockets (not including the Space Shuttle). Nearly five percent
of those rockets have experienced total failure, either blowing up or
wandering so far from course as to be useless. The space shuttle has a
slightly better record of safety — it was destroyed in two of 113
flights. There are lots of millionaires willing to spend one or two
million dollars for a flight into space but how many will risk a two to
five percent chance of death?

Predictably my article generated a lot of criticism, especially from people in the industry, e.g. here and from the CEO of Masten Space systems here.  (I responded briefly at the time.)  Some of the criticism was justified, I should have noted that space tourists don’t want to go as fast or as high as the space shuttle or orbital launch rockets, but most of the criticism was a simple denial that the evidence from decades of space flight was relevant.  "Everything changed with SpaceShip One," I was told.

Unfortunately everything has not changed.  I am sad to report that rockets remain very dangerous.

Surprising evidence on the Flynn Effect

1. Non-verbal IQ has risen more rapidly than has verbal IQ.

2. Performance gains are smallest on the most culturally specific tests, and largest on the most abstract tests.

3. Performance gains, as they occur over time, are roughly constant for all age groups.

4. Problem-solving abilities have seen the biggest performance gains.

5. Gains on the "Ravens" test started occurring before the TV era, much less the computer game era.

#3 is perhaps the biggest surprise to me, as it contradicts most of the obvious explanations for the Flynn effect. 

Those results are summed up in the very interesting "The Flynn effect and its relevance to Neuropsychology," by Merrill Hiscock, Journal of Clinical and Experimental Neuropsychology, 2007.  Here is Andrew Gelman’s post on that paper.

Hiscock puts it well: "..the Flynn effect constitutes a compelling example of large between-group IQ differences [across generations] that are completely environmental."

What is carbon-friendly?

Can this result be true?  The guy claims that food production and refrigeration is so energy-expensive that it is more carbon-friendly to drive your car than to walk.  Walking requires that you eat more to make up the lost energy, as you can lose only so much weight (what’s the relevant margin here?  Ten feet of walking?  A lifetime of walking?).

It is also claimed that: "Paper bags cause more global warming than plastic."  Here is the book, I’ve ordered it and will report in due time.  In the meantime, here is Ezra’s coverage.

From Chicagoboyz, here is a good post on whether tangerines from a distance can be more carbon-friendly than local fruit.  Here is an earlier MR post on the same.

Do pesticides contribute to autism?

Here is the latest, excerpt:

Examining three years of birth records and pesticide data, scientists from the Public Health Department determined that the Central Valley women lived within 500 meters, or 547 yards, of fields sprayed with organochlorine pesticides during their first trimester of pregnancy. Eight of them, or 28%, had children with autism. Their rate of autism was six times greater than for mothers who did not live near the fields, the study said.

There is some attempt to look at larger numbers:

The scientists collected records of nearly 300,000 children born in the 19 counties of the Sacramento and San Joaquin river valleys. Of those children, 465 had autism. The scientists then compared the addresses during pregnancy to state records that detailed the location of fields sprayed with several hundred pesticides.  For most pesticides, no unusual numbers of autism cases were found, but the exception was a class of compounds called organochlorines.

I am mostly skeptical.  There are plenty of autistic children, here and abroad, who were never exposed to these chemicals.  Agricultural valleys in California don’t seem to have especially high rates of autism.  Should I believe "you either get autism from your parents, or in some cases, from pesticides"?  Or "pesticides are a potent epigenetic trigger"?  Or should I believe "they found 465 cases out of 300,000 when they should have found many many more.  Reporting of autism is biased in that sample, and the reporting bias is somehow correlated with certain kinds of agricultural activity."?

So far I’m sticking with the latter.  Four points of note: a) the study author is appropriately cautious, b) he does try to adjust for regional diagnosis center, c) I very much wish this study had a map of incidence, and d) is it really so difficult for the author to discuss what it means that the study is restricted to just one part of California?

Baboon metaphysics

In sum, monkey society is governed by the same two general rules that governed the behavior of women in so many 19th-century novels: stay loyal to your relatives (though perhaps at a distance, if they are a social impediment) but also try to ingratiate yourself with the members of high-ranking families.  The two rules interact in interesting ways.  For members of high-ranking matrilines, the rules of kin-based and rank-based attraction reinforce one another, whereas for the members of low-ranking families they counteract.  A member of a high-ranking matriline is attracted to her kin not only because they are members of the same family but also because they are high-ranking.  A member of a low-ranking family may be attracted to her kin, but she is also drawn away from them by her attraction to unrelated, higher-status individuals.  As a result, high-ranking families are often more cohesive than lower-ranking ones.  Or, to paraphrase Tolstoy’s Anna Karenina, all high-ranking families are alike in their cohesiveness, each low-ranking family is cohesive or not, in its own way.

That is from the excellent Baboon Metaphysics: The Evolution of a Social Mind, by Dorothy L. Cheney and Robert M. Seyfarth.

This book also has the best discussion I have seen of the similarities and differences between human speech and animal vocalization, in this case baboon cries.

Economic Inquiry has a new policy

R. Preston McAfee (a great choice) is the new editor, and he writes in a mass email today:

More
insidious, in my view, is the gradual morphing of the referees from
evaluators to anonymous co-authors. Referees request increasingly
extensive revisions. Usually these represent improvements, but the
process takes a lot of time and effort, and the end result is often
worse owing to its committee-design. Authors, knowing referees will
make them rewrite the paper, are sometimes sloppy with the submission.
This feedback loop – submitting a sloppy paper since referees will
require rewriting combined with a need to fix all the sloppiness – has
led to our current misery. Moreover, the expectation that referees will
rewrite papers, combined with sloppy submissions, makes refereeing
extraordinarily unpleasant. We – the efficiency-obsessed academic
discipline – have the least efficient publication process.

The system is broken.

Consequently, Economic
Inquiry is starting an experiment. In this experiment, an author can
submit under a ‘no revisions’ policy. This policy means exactly what
it says: if you submit under no revisions, I (or the co-editor) will
either accept or reject. What will not happen is a request for a
revision.

I
will ask referees: ‘is it better for Economic Inquiry to publish the
paper as is, versus reject it, and why or why not?’ This policy returns
referees to their role of evaluator. There will still be anonymous
reports.

Authors
who receive an acceptance would have the option of publishing without
changes. If a referee noticed a minor problem and put it in the report,
self-respecting authors would fix the problem. But such fixes would not
be a condition of publication.      

You could try dating women on this basis as well; we’ll see how it goes.  Elsewhere in the world of journals, Science is ending its link to JSTOR, a sad moment for scholarship.