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Physicist, Startup Founder, Blogger, Dad

Thursday, June 26, 2014

Theoreticians as Professional Outsiders

The book also contains essays on Schrodinger, Fisher, Pauling, George Price, and Rashevsky.
Theoreticians as Professional Outsiders: The Modeling Strategies of John von Neumann and Norbert Wiener (Ehud Lamm in Biology Outside the Box: Boundary Crossers and Innovation in Biology, Oren Harman and Michael R. Dietrich (eds.))

Both von Neumann and Wiener were outsiders to biology. Both were inspired by biology and both proposed models and generalizations that proved inspirational for biologists. Around the same time in the 1940s von Neumann developed the notion of self reproducing automata and Wiener suggested an explication of teleology using the notion of negative feedback. These efforts were similar in spirit. Both von Neumann and Wiener used mathematical ideas to attack foundational issues in biology, and the concepts they articulated had lasting effect. But there were significant differences as well. Von Neumann presented a how-possibly model, which sparked interest by mathematicians and computer scientists, while Wiener collaborated more directly with biologists, and his proposal influenced the philosophy of biology. The two cases illustrate different strategies by which mathematicians, the “professional outsiders” of science, can choose to guide their engagement with biological questions and with the biological community, and illustrate different kinds of generalizations that mathematization can contribute to biology. The different strategies employed by von Neumann and Wiener and the types of models they constructed may have affected the fate of von Neumann’s and Wiener’s ideas – as well as the reputation, in biology, of von Neumann and Wiener themselves.
For and Against theory in biology:
... E.B. Wilson articulated the reserved attitude of biologists towards uninvited theoreticians. Wilson’s remarks at the Cold Spring Harbor Symposia on Quantitative Biology in 1934 were ostensibly about the “Mathematics of Growth” but it is impossible to fail to notice their tone and true scope. Wilson suggested orienting the discussion around five axioms or “platitudes” as he called them. The first two are probably enough to get his point across. Axiom 1 states that “science need not be mathematical,” and if that’s not bad enough, axiom 2 solidifies the reserved attitude towards mathematization by stating that “simply because a subject is mathematical it need not therefore be scientific.”

... While the idea of self-reproduction seems incredible, and some might even have thought it to involve a self-contradiction, with objects creating something as complex as they are themselves, von Neumann’s solution to the problem of self-reproduction was remarkably simple. It is based on two operations: (1) constructing an object according to a list of instructions, and (2) copying a list of instructions as is ... This procedure is trivial for anyone computer-literate to understand; it was a remarkable theoretical result in 1948. What, however, does it tell us about biology? It is often observed that von Neumann’s explanation, which involves treating the genetic material both as instructions and as data that is copied as-is, is analogous to the reproduction of cells, since DNA, the analogue of the instruction list, is passively replicated. Von Neumann compared the construction instructions that direct the automaton to genes, noting that genes probably do not constitute instructions fully specifying the construction of the objects their presence stimulates. He warned that genes are probably only general pointers or cues that affect development, a warning that alas did not curtail the “genetic program” metaphor that became dominant in years to come.

Von Neumann noted that his model explained how mutations that do not affect self- replication are possible. If the instruction list specifies not only the self-replicating automaton but also an additional structure, this structure will also be replicated. ...

... As Claude Shannon put it in a 1958 review of von Neumann’s contributions to automata theory, and specifically self-reproducing automata:

If reality is copied too closely in the model we have to deal with all of the complexity of nature, much of which is not particularly relevant to the self-reproducing question. However, by simplifying too much, the structure becomes so abstract and simplified that the problem is almost trivial and the solution is un-impressive with regard to solving the philosophical point that is involved. In one place, after a lengthy discussion of the difficulties of formulating the problem satisfactorily, von Neumann remarks: "I do not want to be seriously bothered with the objection that (a) everybody knows that automata can reproduce themselves (b) everybody knows that they cannot."
See also On Crick and Watson and Reliable Organization of Unreliable Components

Sunday, June 22, 2014

Asia's Cauldron: the South China Sea and DF-21D ASBM

I recommend Robert Kaplan's Asia's Cauldron: The South China Sea and the End of a Stable Pacific. A key question: how effective will conventional ballistic missiles (ASBM: e.g., DF-21D, CEP ~ 10m? recent report) and cruise missiles (ASCM) be against US carrier groups?



Over the last decade, the center of world power has been quietly shifting from Europe to Asia. With oil reserves of several billion barrels, an estimated nine hundred trillion cubic feet of natural gas, and several centuries’ worth of competing territorial claims, the South China Sea in particular is a simmering pot of potential conflict. The underreported military buildup in the area where the Western Pacific meets the Indian Ocean means that it will likely be a hinge point for global war and peace for the foreseeable future.

In Asia’s Cauldron, Robert D. Kaplan offers up a vivid snapshot of the nations surrounding the South China Sea, the conflicts brewing in the region at the dawn of the twenty-first century, and their implications for global peace and stability. One of the world’s most perceptive foreign policy experts, Kaplan interprets America’s interests in Asia in the context of an increasingly assertive China. He explains how the region’s unique geography fosters the growth of navies but also impedes aggression. And he draws a striking parallel between China’s quest for hegemony in the South China Sea and the United States’ imperial adventure in the Caribbean more than a century ago.

To understand the future of conflict in East Asia, Kaplan argues, one must understand the goals and motivations of its leaders and its people. Part travelogue, part geopolitical primer, Asia’s Cauldron takes us on a journey through the region’s boom cities and ramshackle slums: from Vietnam, where the superfueled capitalism of the erstwhile colonial capital, Saigon, inspires the geostrategic pretensions of the official seat of government in Hanoi, to Malaysia, where a unique mix of authoritarian Islam and Western-style consumerism creates quite possibly the ultimate postmodern society; and from Singapore, whose “benevolent autocracy” helped foster an economic miracle, to the Philippines, where a different brand of authoritarianism under Ferdinand Marcos led not to economic growth but to decades of corruption and crime.
See also John Mearsheimer: Can China Rise Peacefully?

Wednesday, June 18, 2014

Chicago Conference on Genetics and Behavior (video)

This is video of my talk at the University of Chicago Conference on Genetics and Behavior back in April. Slides -- they are not very readable in the video. Here's another link to the talk on the Chicago page.

Ability, Effort, and Academic Achievement among Asian Americans

What accounts for the academic success of E. Asians? I would have guessed about equal parts cognitive advantage (ability) and hard work (grinding). The paper below tries to quantify this in more detail using data from two nationally representative cohort studies, comparing students of various of ethnicities who attend the same schools. Note the broad conclusion stated in the abstract applies better to Asian Americans (AAs) in aggregate, and less well to the E. Asian subpopulation alone -- see figures below.
Explaining Asian Americans’ academic advantage over whites (PNAS)

The superior academic achievement of Asian Americans is a well-documented phenomenon that lacks a widely accepted explanation. Asian Americans’ advantage in this respect has been attributed to three groups of factors: (i) socio-demographic characteristics, (ii) cognitive ability, and (iii) academic effort as measured by characteristics such as attentiveness and work ethic. We combine data from two nationally representative cohort longitudinal surveys to compare Asian-American and white students in their educational trajectories from kindergarten through high school. We find that the Asian-American educational advantage is attributable mainly to Asian students exerting greater academic effort and not to advantages in tested cognitive abilities or socio-demographics. We test explanations for the Asian–white gap in academic effort and find that the gap can be further attributed to (i) cultural differences in beliefs regarding the connection between effort and achievement and (ii) immigration status. Finally, we highlight the potential psychological and social costs associated with Asian-American achievement success.

While all four AA subpopulations showed positive differences relative to white students in academic achievement and effort, only the E. Asian subgroup had a cognitive advantage.


From the Supplement: for E. Asians, the academic achievement gap appears to be ~ 1/3 due to cognitive ability and ~ 2/3 due to academic effort, with large uncertainties. For the other subpopulations the results are quite different (and actually rather strange). Click for larger version.

Sunday, June 15, 2014

The Age of Ambition and The Fourth Revolution

Evan Osnos (New Yorker China correspondent; successor to Peter Hessler) on his new book Age of Ambition: Chasing Fortune, Truth, and Faith in the New China.




BONUS: Micklethwait and Wooldridge, co-authors of The Fourth Revolution: The Global Race to Reinvent the State, on CELAP (also here).
WSJ: Buried in a Shanghai suburb, close to the city's smoggy Inner Ring Road, the China Executive Leadership Academy Pudong, or Celap, seems to have a military purpose. Razor wire curls along the fences around the huge compound, and guards stand at its gate. But drive into the campus from the curiously named Future Schedule Street, and you enter what looks like Harvard as redesigned by Dr. No.

In the middle of the academy stands a huge, bright-red building in the shape of a desk, with an equally monumental, scarlet inkwell beside it. Surrounding it are lakes and trees, libraries, a sports center and a series of low, brown dormitory buildings, all designed to look like unfolded books. Celap calls this a "campus," but the organization is too disciplined, hierarchical and businesslike to be a university. The locals are closer to the mark: They call it a "Cadre Training School." This is an organization bent on world domination.

Celap's students are China's future leaders. The egalitarian-looking sleeping quarters mask a strict pecking order, with suites for senior visitors from Beijing. The syllabus eschews ideology in favor of technocratic solutions. The two most common questions, says one teacher, are: What works best? And can it be applied here?

Today, Chinese students and officials hurtle around the world, studying successful models from Chile to Sweden. Some 1,300 years ago, Celap's staff remind you, imperial China sought out the brightest young people to become civil servants. For centuries, these mandarins ran the world's most advanced government—until the Europeans and then the Americans forged ahead. Better government has long been one of the West's great advantages. Now the Chinese want that title back.

Western policy makers should look at this effort the same way that Western businessmen looked at Chinese factories in the 1990s: with a mixture of awe and fear. Just as China deliberately set out to remaster the art of capitalism, it is now trying to remaster the art of government. The only difference is a chilling one: Many Chinese think there is far less to be gained from studying Western government than they did from studying Western capitalism. They visit Silicon Valley and Wall Street, not Washington, D.C.

The West pulled ahead of "the rest" because it created a permanent contest to improve its government machinery. In particular, it pioneered four great revolutions. The first was the security revolution of the 16th and 17th centuries, when Europe's princes created modern nation states. As Spain, England and France competed around the globe, they improved statecraft in a way that introverted China never did.

The second great revolution, of the late 18th and 19th centuries, championed liberty and efficiency. Aristocratic patronage systems were replaced with leaner, more meritocratic governments, focused on providing services like schools and police. Under Britain's thrifty Victorians, the world's most powerful country reduced its tax take from £80 million in 1816 to less than £60 million in 1860—even as its population increased by 50%.

This vision of a limited but vigorous state was swept away in the third revolution. In the 20th century, Western government provided people with ever more help: first health care and unemployment pay but eventually college education and what President Lyndon B. Johnson called the Great Society. Despite counterattacks, notably the 1980s half-revolution of Ronald Reagan and Margaret Thatcher, the sprawling welfare state remains the dominant Western model.

In the U.S., government spending increased from 7.5% of GDP in 1913 to 19.7% in 1937, to 27% in 1960, to 34% in 2000 and to 42% in 2011. Voters continue to demand more services, and politicians of all persuasions have indulged them—with the left delivering hospitals and schools, the right building prisons, armies and police forces, and everybody creating regulations like confetti.

In all three of these revolutions, the West led the way. But now, as China's ambitions illustrate, the emerging world is eager to compete again.

And why not? Over the past two years, while the U.S. political system has torn itself apart over Obamacare, China has extended pension coverage to an additional 240 million rural people. Lee Kwan Yew's authoritarian Singapore offers dramatically better education and health care than Uncle Sam, with a state that is a fraction of the U.S.'s size. If you are looking for the future of health care, India's attempt to apply mass-production techniques to hospitals is part of the answer. So too, Brazil's conditional cash transfers are part of the future of welfare. At the very least, the West no longer has a monopoly on ideas. ...

The first is that, while Western voters have overloaded the state with demands, they abhor the result. The U.S. Congress regularly scores an approval rating of 10%. In Britain, membership of the Tory Party slid from 3 million in 1950 to 123,000 today, a performance that would have put a private company into receivership. Voters are frustrated.

Second, government is going broke. The U.S. government has run a surplus only five times since 1960; France hasn't had one since 1974-75. And now the demographic challenge of caring for aging populations will push even left-wing parties toward hard choices about what—and whom—they want to save.

The third reason is more positive. Government can be reformed, but only if Western politicians and electorates decide what they want it to do.

Our own answer is, simply, much less. The overloaded modern state is a threat to democracy: The more responsibilities Leviathan assumes, the worse it performs them, and the angrier citizens get. ...

You may disagree. But this is part of a bigger argument that the West must start having now. A great contest is under way to reinvent the state, and the Chinese have the advantage of knowing what the consequences are if they lose.

Saturday, June 14, 2014

Directional Personality and mate preferences

Some good old evo psych fun -- guaranteed to annoy certain people :-)  Nevertheless, interesting because it raises the point that measurements of Personality (e.g., Big 5 or other constructs) are complicated by the fact that people can behave differently depending on the target of the behavior.

Plenty of sociopaths in large organizations are pleasant to superiors but unpleasant to those below them in the hierarchy.
Kind toward whom? Mate preferences for personality traits are target specific (Evolution and Human Behavior 31 (2010) 29–38)

Previous mate preference studies indicate that people prefer partners whose personalities are extremely kind and trustworthy, but relatively non-dominant. This conclusion, however, is based on research that leaves unclear whether these traits describe the behavior a partner directs toward oneself, toward other classes of people or both. Because the fitness consequences of partners' behaviors likely differed depending on the classes of individuals toward whom behaviors were directed, we predicted that mate preferences for personality traits would change depending on the specific targets of a partner's behavioral acts. Consistent with this, two experiments demonstrated that people prefer partners who are extremely kind and trustworthy when considering behaviors directed toward themselves or their friends/family, but shift their preferences to much lower levels of these traits when considering behaviors directed toward other classes of individuals. In addition, both sexes preferred partners who direct higher levels of dominance toward members of the partner's own sex than toward any other behavioral target category, with women preferring levels of dominance toward other men as high as — or higher than — levels of kindness and trustworthiness. When asked to rate traits for which the behavioral target was left unspecified, furthermore, preferences were very similar to self-directed preferences, suggesting that previous trait-rating studies have not measured preferences for partners' behaviors directed toward people other than oneself. These findings may provide a basic contribution to the mate preference literature via their demonstration that ideal standards for romantic partners are importantly qualified by the targets of behavioral acts.

In the figure below, women (top graph) seem to prefer a larger self--rival asymmetry in their mates than men do. In other words, women like men who are kind to them but who are socially dominant towards other men. (Proponents of Game would argue that even this reflects a bit of false consciousness -- that women actually prefer men who are socially dominant towards them!) Click for larger version.


Thanks to a reader for the reference.

Saturday, June 07, 2014

Large-Scale Psychological Differences Within China

The study below discusses a psychological/cognitive/personality gradient between N and S China, possibly driven by a history of wheat vs rice cultivation.
Large-Scale Psychological Differences Within China Explained by Rice Versus Wheat Agriculture (Science)

Cross-cultural psychologists have mostly contrasted East Asia with the West. However, this study shows that there are major psychological differences within China. We propose that a history of farming rice makes cultures more interdependent, whereas farming wheat makes cultures more independent, and these agricultural legacies continue to affect people in the modern world. We tested 1162 Han Chinese participants in six sites and found that rice-growing southern China is more interdependent and holistic-thinking than the wheat-growing north. To control for confounds like climate, we tested people from neighboring counties along the rice-wheat border and found differences that were just as large. We also find that modernization and pathogen prevalence theories do not fit the data.

Editor Summary: On a diverse and large set of cognitive tests, subjects in East Asian countries are more inclined to display collectivist choices, whereas subjects in the United States are more inclined to score as individualists. Talhelm et al. (p. 603; see the Perspective by Henrich) suggest that one historical source of influence was societal patterns of farming rice versus wheat, based on three cognitive measures of individualism and collectivism in 1000 subjects from rice- and wheat-growing regions in China.
The first author of the paper is interviewed below; his comments are quite illuminating. None of the discussants entertain the notion that any of these group differences could be partially genetic in causation.
Sinica: Rice, Wheat and Air Filters

This week on Sinica, we're delighted to be joined by Thomas Talhelm, Ph.D. candidate in psychology at the University of Virginia and author of a recent paper proposing a fascinating connection between rice and wheat-growing communities, and persistent differences in psychological orientations of people from different parts of China. So join us as we talk about divorce, collectivism and violence, and get the dirt on all the various tests psychologists are using to measure it all here in the Middle Kingdom.

And even if psychology isn't your thing, we suspect that breathing is -- which is another reason to listen. In addition to his growing reputation in academic circles, Thomas is also known in China for his production and proselytization of do-it-yourself air filtration kits, which he sells through his company Smart Air Filters. If you are interested in getting a filter without spending a fortune, be sure to check them out.
I corresponded briefly with Talhelm, pointing out that his results are already a part of Chinese folk sociology, and even remarked upon by European visitors to China in the 18th century.

Friday, June 06, 2014

Rare mutations and severe intellectual disability



The paper below describes rare de novo mutations which cause severe intellectual disability. See also Structural genomic variants (CNVs) affect cognition.

By the principle of continuity, I suspect that rare variants of smaller negative effect on cognitive ability also exist. These alleles, although harder to detect, would account for part of the observed population variation in the normal range. As discussed in an earlier post (Common variants vs mutational load), these are likely responsible for additional heritability not included in the h2 ~ 0.5 due to common variants estimated from GCTA.
Genome sequencing identifies major causes of severe intellectual disability (Nature)

Severe intellectual disability (ID) occurs in 0.5% of newborns and is thought to be largely genetic in origin1, 2. The extensive genetic heterogeneity of this disorder requires a genome-wide detection of all types of genetic variation. Microarray studies and, more recently, exome sequencing have demonstrated the importance of de novo copy number variations (CNVs) and single-nucleotide variations (SNVs) in ID, but the majority of cases remain undiagnosed3, 4, 5, 6. Here we applied whole-genome sequencing to 50 patients with severe ID and their unaffected parents. All patients included had not received a molecular diagnosis after extensive genetic prescreening, including microarray-based CNV studies and exome sequencing. Notwithstanding this prescreening, 84 de novo SNVs affecting the coding region were identified, which showed a statistically significant enrichment of loss-of-function mutations as well as an enrichment for genes previously implicated in ID-related disorders. In addition, we identified eight de novo CNVs, including single-exon and intra-exonic deletions, as well as interchromosomal duplications. These CNVs affected known ID genes more frequently than expected. On the basis of diagnostic interpretation of all de novo variants, a conclusive genetic diagnosis was reached in 20 patients. Together with one compound heterozygous CNV causing disease in a recessive mode, this results in a diagnostic yield of 42% in this extensively studied cohort, and 62% as a cumulative estimate in an unselected cohort. These results suggest that de novo SNVs and CNVs affecting the coding region are a major cause of severe ID. Genome sequencing can be applied as a single genetic test to reliably identify and characterize the comprehensive spectrum of genetic variation, providing a genetic diagnosis in the majority of patients with severe ID.

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Wednesday, June 04, 2014

Strategic War (with cards)



War is a simple card game played by children. The most common version does not require decisions, so it's totally deterministic (outcome is determined) once the card order in each deck is fixed. Nevertheless it can be entertaining to watch/play: there are enough fluctuations to engage observers, mainly due to the treatment of ties. The question of how to determine the winner from the two deck orderings (without actually playing the entire game, which can take a long time) was one of the first aspects of computability / predictive modeling / chaotic behavior I thought about as a kid. This direction leads to things like classification of cellular automata and the halting problem.

My children came home with a version designed to teach multiplication -- each "hand" is two cards, rather than the usual single card, and the winner of the "battle" is the one with the higher product value of the two cards (face cards are removed). I thought this was still too boring: no strategy (my kids understood this right away, along with the meaning of deterministic; this puts them ahead of some philosophers), so I came up with a variant that has been quite fun to play.

Split the deck into red and black halves, removing face cards. Each hand (battle) is played with two cards, but they are chosen by each player. One card is placed face down simultaneously by each player, and the second cards played are chosen after the first cards have been revealed (flipped over). Winner of most hands is the victor.

This game ("strategic war") is simple to learn, but complex enough that it involves bluffing, calculation, and card counting (keeping track of which cards have been played). A speed version, with, say, 10 seconds allowed per card choice, goes very fast.

Has anyone seen heard of this game before? It's a bit like repeated two card poker (heads up), drawing from a fixed deck. Note the overall strength of hands for each player (combined multiplicative value of all cards) is fixed and equal. Playing strong hands early means weaker hands later in the game. The goal is to win each hand by as small a margin as possible.

Are there strategies which dominate random play (= select first card at random, second card from range not exceeding highest card required to guarantee a win)?




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Sunday, June 01, 2014

Income, Cognitive Ability, and Education

The figure below is from Schooling, Intelligence, and Income (1997, American Psychologist) by Ceci and Williams.

Cognitive ability has a strong impact on earnings at each level of educational attainment.


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Those genius babies

This video has almost a million views. I think it's very well done :-)



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