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Friday, July 31, 2009
Genetic Variations Associated With Red Hair Color and Fear of Dental Pain, Anxiety Regarding Dental Care and Avoidance of Dental Care:
Background. Red hair color is caused by variants of the melanocortin-1 receptor (MC1R) gene. People with naturally red hair are resistant to subcutaneous local anesthetics and, therefore, may experience increased anxiety regarding dental care. The authors tested the hypothesis that having natural red hair color, a MC1R gene variant or both could predict a patient's experiencing dental care-related anxiety and dental care avoidance. Labels: Behavior Genetics
Wednesday, July 29, 2009
One of the major issues when you discuss topics with people with whom you disagree is conflicts as to the acceptability of a particular chain of reason or line of analysis. There are usually implicit assumptions within any given analyses which need to be fleshed out, and to do so is usually time consuming. To give an example, I do not agree with the assertion that "IQ has nothing to do with intelligence." This is a very common background assumption for many people, so many analyses simply make no sense when you do, or don't, accept the viability of a concept like IQ. Talking about the issues at hand is a waste of time when there are such differences in the axioms and background structure of the models one holds, and I can understand why the temptation of extreme subjectivism emerges so often. Looking through the glass darkly can obscure the reality that beyond the glass there is a clear and distinct world.
That is why I think it is important to expose and avoid falsity of fact, however trivial. It is often much easier to agree on basic facts, especially quantitative ones. I do not say that it is alway easy, but it is certainly much easier. This is why weblogs such as The Audacious Epigone are so useful, their bread & butter is fact-checking. When blogs first began to make a splash in 2002 the whole idea of "fact checking your ass" was in vogue, but it doesn't seem like it's really worked out. What's really happened is a proliferation of Google Pundits, who know the answers they want, and know how to get those answers out of the slush pile of answers via an appropriate query. Google Punditry is not exploratory data analysis, it's fishing around for data to match your preconceptions. Many GNXP readers may not agree with the conservative politics of The Inductivist or The Audacious Epigone, but their data-driven blog posts are often formatted such that you don't even need to read the commentary after their tables. Eight months ago Kevin Drum of Mother Jones promised to do more digging through the GSS after I'd pointed him to the resources, but it doesn't seem like it has happened. My GSS and WVS related posts at Secular Right often get picked up by mainstream pundits like Andrew Sullivan, but the utilization of the GSS or WVS interface hasn't spread. Why? One friend suggested that perhaps people fear what they might find out. I do agree that the GSS (or WVS) aren't oracles which are infallible. There are obvious issues with representativeness in the WVS, and the small N's for some categories in the GSS mean there's a lot of noise. But with that caution aside, these objections are clear and distinct when one begins with these tools and data sets. In fact, with something like the GSS or WVS you can check your intuitions about representativeness by digging a little deeper. Addendum: When I do GSS posts people often object in the form of "your data doesn't prove that!" Interestingly, this objection comes up even when there's a minimum of commentary. Of course the sort of surface scratches that I do don't definitively disprove or prove much, at least in general. Rather, they should be starting off points for further digging. Labels: data
The paper Eight Americas: Investigating Mortality Disparities across Races, Counties, and Race-Counties in the United States, has this fascinating map (reformatted a bit):
 As you can see there is a great deal of variance in white male life expectancy in the United Sates. Compare to this map:  "American" is probably just Scotch-Irish in this case. It is noticeable it seems on this map that the countries in central Texas where Anglo ancestry is dominated by those of German origin exhibit high life expectancy. In any case, you can actually look at the county-by-county data set from the above paper in regards to life expectancies. The minimum male life expectancy in any county is 62, with the maximum being 80.30. The median is 73.60 and the mean 73.38 (these data are ~2000). There's a "long tail" of sparsely populated counties with low male life expectancies as evidenced by the lower mean value than the median. The standard deviation across the counties is 2.35 years. As can be seen on the first map there is a strong geographic component to the interregional differences. Below is a chart which reports the proportion of counties in the 50 states which have a life expectancy at, or above, the Canadian national value as of the year 2000 (again, both these values are for males).  Some states obviously have very few counties. But Kentucky has 120. None of them are at the Canadian level. Labels: data
Tuesday, July 28, 2009
A reader points out that David Shenk is blogging genetics & IQ over at The Atlantic. If you have some free time to kill in comment sections, you might be interested. To get a flavor, a post titled The Truth About IQ has a footnote to Stephen Jay Gould's Mismeasure of Man.
Labels: IQ
Monday, July 27, 2009
A new neuroscience take on moral psychology, Right or Wrong? The brain's fast response to morally objectionable statements:
How does the brain respond to statements that clash with a person's value system? We recorded EEG potentials while respondents from contrasting political-ethical backgrounds completed an attitude survey on drugs, medical ethics, social conduct and other issues. Our results show that value-based disagreement is unlocked by language extremely rapidly, within 200-250 milliseconds after the first word at which a statement begins to clash with the reader's value system (e.g., "I think euthanasia is an acceptable/unacceptable...."). Furthermore, strong disagreement rapidly influences the ongoing analysis of meaning, indicating that even very early processes in language comprehension are sensitive to a person's value system. Our results testify to rapid reciprocal links between neural systems for language and for valuation. You can read a preprint at the link, or, ScienceDaily's summary. The authors reference Jonathan Haidt's findings, which suggest that moral values have less to do with reason than emotionally colored intuition. Anyone familiar with the importance of emotion in decision making and judgement, or the heuristics & biases literature, won't be surprised by these results. The main obvious implication is that yes, psychology does manifest biophysically in the brain. My interest is not in general average propensities, but individual differences. Bryan Caplan has shown for example that intelligence is correlated with economic rationality. To some extent one might view this as another fruit of high g, but another unrelated component might be the way in which emotions express themselves when faced with assertions counter to one's intuition or moral outlook. One problem that I face with many extremely intelligent individuals is a reflexive aversion to entertaining possibilities or thought experiments which are abhorrent to their moral or political orientation. One the one hand these emotional responses probably have an important role in sorting and ranking the order in which one performs cognitive tasks. Many thought experiments are after all useless. But when feeling has reason too tightly on the leash there is unfortunately a tendency for it to constrain the search space of intellectual possibilities. It would be interested to see if there is an aspect of rationality which is related to the ability of individuals to suppress or shunt aside the power of emotional response, a dynamic which I presume could be ferreted out by various imaging techniques. As an analogy, those with higher g may have more powerful tools, but to some extent there is something to be said for willingness to use the tools one has on hand as well. Labels: Biological Psychology, Neuroscience
Sunday, July 26, 2009
The Singularity Summit is in New York this year, October 3-4th. Here's the program.
Labels: Singularity
Saturday, July 25, 2009
This series of posts attempts to identify the key propositions of 'Darwinism', in the sense of what Charles Darwin himself believed, and to assess their current standing. Part 1 dealt with 'The Pattern of Evolution'. Part 2 considered the 'Mechanisms of Evolution'. Part 3 considers Darwin's views and speculations on the subject of Heredity. I will cover the subject under the headings:
What Darwin got right What Darwin got wrong What Darwin didn't know Pangenesis Note on sources As previously, I will cite the Origin from Charles Darwin: The Origin of Species: a Variorum Text, edited by Morse Peckham, 1959, reprinted 2006. Darwin regarded the Origin as an 'abstract' of his theory of evolution, and intended to present it more fully in several longer works. The 2-volume Variation of Animals and Plants under Domestication (1868) carries out this intention for the chapters in the Origin on 'Variation under Domestication', 'Laws of Variation', and part of 'Hybridism'. The rest of the grand plan was never completed. WHAT DARWIN GOT RIGHT 1. LIKE PRODUCES LIKE Darwin's most fundamental proposition on heredity is that 'like produces like' [Origin, 85]; in other words, offspring resemble their parents, or in modern technical terms, there is positive heritability for most traits. Darwin believed this to be the case both for relatively large variations ('sports') and for the smaller variations that he called 'individual differences'. This is fundamental to his theory because 'any variation which is not inherited is unimportant for us'. [85] Darwin's evidence for this basic proposition is taken mainly from domesticated animals and plants, and is set out at length in the first volume of Variation, with 100 pages on pigeons alone. He believed that the evidence was overwhelming, and dismissed objections as merely 'theoretical'. Modern genetic theory and experiment generally supports Darwin. 2. CHANGE CAN BE PERMANENT Before Darwin it was often argued that changes in animals and plants under domestication were only temporary, and that in the wild they would always revert to the wild form. Darwin accepted that if conditions changed, the characters of the animals or plants would also change as a result of natural selection, but he did not accept that they would always revert exactly to the original wild form. He emphasised that the new forms could continue indefinitely if conditions were constant and the animals or plants bred only among themselves: 'the antiquity of various breeds clearly proves that they remain nearly constant as long as their conditions of life remain the same' [Variation, vol.2, 416]. Darwin's belief in the potential permanence of change was challenged by Francis Galton, who believed that small quantitative changes would wash out in a few generations by 'regression towards the mean', and only the discontinuous variations known as 'sports' would resist this regression. Karl Pearson later showed that Galton's arguments rested on a misunderstanding of his own principle of regression. 3. THERE IS NO LIMIT TO CUMULATIVE CHANGE Another difficulty for Darwin was the widespread belief that variations under domestication could never go beyond the normal limits of differences between species. One of the recurring points made in Variation is that the differences in external morphological characters between domesticated varieties were often greater than those between recognised wild species, or even genera: see for example Variation vol. 1, 36 (dogs), 49 (horses), 70 (pigs), 115 (rabbits), 133, 157 (pigeons). From modern knowledge of genetics there is no reason to believe in any inherent limit to cumulative variation, though there may of course be physiological limits, e.g. to the speed of race-horses. WHAT DARWIN GOT WRONG 4. INHERITANCE OF ACQUIRED CHARACTERISTICS As discussed in Part 2, like most biologists of his time Darwin believed in the inheritance of acquired characteristics (IAC). (See especially chapter 5 of the Origin, and chapter 24 of Variation.) It is now generally accepted that, with some special exceptions, IAC does not occur. (In the last few years some biologists have argued that 'transgenerational epigenetic inheritance' is widespread, but even if this turns out to be true, it has little to do with IAC in the traditional sense.) In Darwin's defence it may be said that in his day there were many phenomena which could most easily be explained by IAC. There also appeared to be strong experimental evidence to support it. Darwin accepted the claims of the French physiologist Brown-Sequard to have produced IAC in guinea pigs. In the first edition of Variation Darwin described this as 'the most remarkable and trustworthy fact' in support of IAC (vol.2, 24), while in the second edition, following further reports by Brown-Sequard, and apparent independent replication, he upgraded this to 'conclusive evidence' (2nd. edn, 1875, vol.1, 488). It was only after objections were raised by Weismann to the very possibility of IAC that biologists generally began to question the kind of evidence previously used. An example is the fact that animals living in caves are often congenitally blind. Sometimes their eyes have degenerated or disappeared, sometimes they are present but non-functional. Darwin thought that IAC resulting from disuse was the best explanation, as 'it is difficult to imagine that eyes, though useless, could be in any way injurious to animals living in darkness', and their deterioration could therefore not be explained by natural selection. Nor could it be explained by 'economy of growth' in cases where the eyes were still full-sized. It would now generally be agreed that when selection for any complex adaptation is relaxed, the genes underlying that adaptation will accumulate mutations, most of which will tend to destroy the adaptation. But this explanation was hardly available to Darwin, and it is a departure from a purist interpretation of natural selection, since it assumes that phenotypic change in the absence of selection is biased in one direction (towards deterioration). Another case that is difficult to explain by simple ideas of natural selection is the inheritance of callosities of the skin, as in camels, etc. Such callosities may be produced by friction in the lifetime of an animal, but in some species they are already developed before birth, and it seems most unlikely that genetic mutations would purely by chance produce congenital callosities just where they are needed. In such cases modern biologists would probably appeal to C. H. Waddington's concept of 'genetic assimilation', which is strictly consistent with natural selection but does give a causal role to the experience of the animal's parents, and therefore has the appearance of IAC (see John Maynard Smith, The Theory of Evolution, 3rd. edn., under index reference to Waddington.) 5. THE CAUSES OF VARIATION Darwin believed that all hereditary variation has some cause, usually change in the environment. This would not now be accepted. Strong environmental influences, such as radiation or powerful chemicals, can induce mutations, but in general mutation is due to chance failures in the mechanism of replication. 6. TELEGONY One belief about heredity prevalent in Darwin's time was that of telegony: the idea that a male who mates with a female may also influence her offspring from subsequent matings with other males. This was widely believed by animal breeders, and supported by a few apparently well-documented cases, the best-known of which was that of Lord Morton's mare. Lord Morton had mated one of his mares with a quagga, producing hybrid offspring, but one of the subsequent matings of the same mare with an ordinary horse had produced offspring with stripes, resembling a quagga. This and other cases were accepted by Darwin as proof that telegony could occur. They would now be dismissed as coincidence or bad observation (e.g. unobserved 'sneak' matings). In writing this I assumed that the idea of telegony was long dead, but I have found the following at a dog-breeding website: This subject, "Does the first impregnation of the female have any influence upon the progeny of subsequent breeding to other sires?" has been for years, and still remains, a disputed question. Scientists are arrayed on both sides of the question. Among dog breeders, the popular opinion is that it does, and many of the breeders who look with suspicion upon a bitch which has suffered a misalliance have had personal experiences with which to support their position Some ideas die hard! So far as I know there is no support whatever for telegony among modern scientists. 7. GRAFT HYBRIDS When a plant is grafted onto a stock of a different species, the vegetation growing from the graft sometimes combines characteristics of both species, and can be propagated permanently by cuttings. Darwin attributed this to a true hybridisation of the two species, involving a permanent mixture of their hereditary material. The phenomenon observed is apparently a genuine one (if rare) but would now be attributed to the formation of chimaeras (mixtures of genetically different cells) , rather than a true hybridisation. 8. EFFECT OF POLLEN ON THE MOTHER PLANT Darwin accepted claims that pollen occasionally affected the tissues of the mother plant, and not just the offspring. This would now be rejected as coincidence or faulty observation. WHAT DARWIN DIDN'T KNOW What Darwin didn't know about heredity was the whole of modern genetics, from Mendelian ratios to DNA and the genetic code. He (and others of his generation) lacked even the most basic facts about the mechanism of heredity, such as the role of chromosomes and the process of recombination. In Darwin's time it was not even certain that fertilisation of an egg involves only one sperm (or pollen grain), and Darwin accepted evidence that sometimes more than one was required. But I think the most serious gap in Darwin's knowledge was the concept of segregation. The idea that an offspring receives a quasi-random selection of genetic material from each parent, which together makes up the unique genotype of the offspring, is entirely absent from Darwin's thinking. It was not impossible for such a concept to be formed in Darwin's time, since Mendel achieved it, and Francis Galton came close. Darwin himself was aware of many facts which are easily explained by segregation. It is often supposed that Darwin believed in a doctrine of 'blending inheritance', in which an offspring is always intermediate between its parents, but this is an oversimplification of his position. He was aware of many traits that do not 'blend', and of some that appear 'prepotent', while others may be 'latent' and reappear in later generations. These are close to the Mendelian ideas of dominant and recessive. But Darwin never worked out a quantitative theory of such phenomena, and he lacked the grasp of basic combinatorial mathematics which guided Mendel and Galton in that direction. PANGENESIS Darwin attempted to account for the phenomena of heredity with his 'Provisional Hypothesis of Pangenesis', as set out in chapter 27 of Variation. This is quite an elaborate theory, but it can be summarised in four main points: a. each unit of the body (and probably each cell) produces particles, known as gemmules, which are capable in the right circumstances of reproducing units of the same type b. gemmules of different kinds are diffused through the fluids of the body c. in sexual reproduction, gemmules from all over the body are packaged into sperms and ova d. in the process of individual growth and development, gemmules give rise to cells of the kind from which they were themselves derived, in the proper order and place determined by their 'mutual affinities'. By these principles Darwin attempts to explain not only the normal course of reproduction and development, but such supposed phenomena as IAC and telegony. IAC, for example, can be explained by assuming that the greater or lesser use of an organ influences the number of gemmules produced and entering the reproductive system. In the light of modern knowledge the theory of pangenesis is almost entirely false. Its only useful component is the principle that the units of heredity are physical particles, rather than, say, fluids, immaterial influences, or vibrations of some kind, as supposed in some rival theories. The most obvious weakness in the theory is the idea that gemmules are diffused through the body and collected into the sperms and ova (sometimes known as the 'transport hypothesis'). No-one had ever observed such mobile gemmules, and Darwin's only defence was to point out that they must be extremely small, like many disease organisms (e.g. those responsible for smallpox) which had not been observed but must exist. By the end of the 19th century it was widely accepted that the material of heredity was contained in the chromosomes, which left no place for loose gemmules circulating round the body. The main reason for Darwin's adoption of the transport hypothesis was the need to explain IAC. If IAC in the traditional sense occurs, then there must be some feedback from the affected parts of the body to the reproductive organs. The transport hypothesis meets this need. Darwin deserves some credit for recognising the need for a mechanism to explain IAC, which had previously been lacking. Historically, the theory of pangenesis was important in highlighting the implausibility of such a mechanism, and therefore of IAC itself. Francis Galton was the first to seriously question the existence of IAC, and his scepticism about it arose directly from his own attempts to test pangenesis through experiments in blood transfusion. De Vries, Weismann, and other pioneers of modern genetics, were also influenced by the need to develop alternatives to Darwin's theory. For example, De Vries (one of the rediscoverers of Mendel's laws) called his own model of heredity 'intracellular pangenesis', as it was based on Darwin's theory with the 'transport hypothesis' left out. Summing up, Darwin had little (correct) knowledge about the mechanisms of heredity, and much of what he thought he knew was in fact wrong. Fortunately, this had little effect on his theory of natural selection, as this depended only on the existence of an adequate supply of heritable variation, from whatever source. Darwin concluded from his study of domesticated animals and plants that an adequate supply of heritable variation did exist, and this has been amply vindicated by modern genetics.
Thursday, July 23, 2009
Lactase persistence, pastoralism in Africa, don't know in Europe
posted by
Razib @ 7/23/2009 11:41:00 PM
Impact of Selection and Demography on the Diffusion of Lactase Persistence:
The lactase enzyme allows lactose digestion in fresh milk. Its activity strongly decreases after the weaning phase in most humans, but persists at a high frequency in Europe and some nomadic populations. Two hypotheses are usually proposed to explain the particular distribution of the lactase persistence phenotype. The gene-culture coevolution hypothesis supposes a nutritional advantage of lactose digestion in pastoral populations. The calcium assimilation hypothesis suggests that carriers of the lactase persistence allele(s) (LCT*P) are favoured in high-latitude regions, where sunshine is insufficient to allow accurate vitamin-D synthesis. In this work, we test the validity of these two hypotheses on a large worldwide dataset of lactase persistence frequencies by using several complementary approaches. The "calcium hypothesis" idea is of course one of the explanations for light skin in Northern Europe as well. The locus responsible for 1/3 of the skin color difference between Africans and Europeans, SLC24A5, is a relative recent sweep, on the order of the last 10,000 years. The authors do caution to be careful about the assumptions of their model. Point taken to heart, as I don't think they have a good enough grasp on the fine-grained variation in the lactase persistence alleles and how they track ecology within Europe. The Greenland Norse did not raise cattle just because of lack of Vitamin D (which they ended up getting through a shift toward a marine diet in any case), rather, there were ecological constraints in terms of the maximum productivity of grain-based subsistence farming (particularly with wheat in cold damp climates). In the conclusion of the paper it is noted that Iberia is a good test case of the model, and more data needs to be gathered there. If it is gene-culture coevolution than many Iberian peoples should be lactase persistent, but if it is due to Vitamin D, they should not be. Labels: Genetics
Wednesday, July 22, 2009
Over at ScienceBlog:
I would like to invite discussion on my paper, On Fodor on Darwin On Evolution, which is a critique of Jerry Fodor's Hugues Leblanc Lectures at UQAM on "What Darwin Got Wrong".... No comments on the post yet, so GNXP readers should check out the paper. Labels: Evolutionary Psychology
Tuesday, July 21, 2009
In the Angry Nintendo Nerd's video about the Virtual Boy -- a short-lived video game console that claimed to offer a "virtual reality" experience -- he says that back in the mid-1990s, it seemed like the coolest thing, but that now no one cares about virtual reality. This, he claims, is why even with better technology than before, no one is making virtual reality systems for the average consumer anymore. Certainly that seems true for pop culture: the Virtual Boy, the movies The Lawnmoer Man and The Matrix, Aerosmith's video for "Amazing," and a whole bunch of video games with "virtual" in the title came out then, vs. nothing like that now.
But when I went to check the NYT, I found a little surprise. Sure enough, there was a flaring up and dying down of the phrase that jibes with what we'd expect -- but there's been a modest yet steady increase in the phrase's usage since 2003. I skimmed the titles of the articles and didn't notice any clear pattern; maybe they're simply using it more in military training, and the news items are about that. Whatever it is, there's something to be explained. Not knowing anything about virtual reality, I'll leave it up to others to hazard a better guess. The graph of its appearance in the NYT is below the fold. Here's the first epidemic craze, followed by a recent increase:  Hmm. Labels: Technology
Genetic background & medicine, HIV & differences between blacks & whites
posted by
Razib @ 7/21/2009 01:24:00 PM
The Duffy-null state is associated with a survival advantage in leukopenic HIV-infected persons of African ancestry:
Persons of African ancestry, on average, have lower white blood cell (WBC) counts than those of European descent (ethnic leukopenia), but whether this impacts negatively on HIV-1 disease course remains unknown. Here, in a large natural history cohort of HIV-infected subjects we show that although leukopenia...was associated with an accelerated HIV disease course, this effect was more prominent in leukopenic subjects of European than African ancestry. The African-specific -46C/C genotype of Duffy Antigen Receptor for Chemokines (DARC) confers the malaria-resisting, Duffy-null phenotype, and we found that the recently described association of this genotype with ethnic leukopenia extends to HIV-infected African Americans (AA). The association of Duffy-null status with HIV disease course differed according to WBC but not CD4+ T cell counts, such that leukopenic but not non-leukopenic HIV+ AAs with DARC -46C/C had a survival advantage compared with all Duffy-positive subjects. This survival advantage became increasingly pronounced in those with progressively lower WBC counts. These data highlight that the interaction between DARC genotype and the cellular milieu defined by WBC counts may influence HIV disease course, and this may provide a partial explanation of why ethnic leukopenia remains benign in HIV-infected African Americans, despite immunodeficiency. Duffy status is a highly ancestrally informative trait. This is a case where the relatively low between population variance found among humans does not apply. Rather, it seems that the Duffy null phenotype is a recent adaptation to malaria among West Africans. Because malaria has such a strong fitness implication many independent genetic adaptations have emerged, many of them with other negative side effects. On net individuals with side effects may still have higher fitness in an environment where malaria is endemic. Sometimes the net benefit is most evidence on a population wide scale, sickle-cell anemia is a deleterious homozygote which exists because of the much higher frequency of heteryzogytes vis-a-vis wild type homozygotes. Many malaria adaptations exhibit the large effect dynamic and suboptimal characteristic which one might except from the early stages of natural selection in a Fisherian model. You deal with the adaptive pressures of the present and let the future take care of itself. In this case, the future involved HIV: The researchers found that leukopenia was generally associated with a faster disease progression from HIV to AIDS, independent of known predictors of AIDS development. "On average, leukopenic European Americans progressed nearly three times faster than their non-leukopenic African or European counterparts," explained Hemant Kulkarni, MD, first author of this study. "However, leukopenic African Americans had a slower disease course than leukopenic European Americans, even though twice as many African Americans in the study had leukopenia." There are no doubt details in the genetic architecture of those with the null genotype worth future investigation. Labels: Genetics, human biodiversity, Population genetics, race
Monday, July 20, 2009
Partial penetrance facilitates developmental evolution in bacteria:
Development normally occurs similarly in all individuals within an isogenic population, but mutations often affect the fates of individual organisms differently...This phenomenon, known as partial penetrance, has been observed in diverse developmental systems. However, it remains unclear how the underlying genetic network specifies the set of possible alternative fates and how the relative frequencies of these fates evolve...Here we identify a stochastic cell fate determination process that operates in Bacillus subtilis sporulation mutants and show how it allows genetic control of the penetrance of multiple fates. Mutations in an intercompartmental signalling process generate a set of discrete alternative fates not observed in wild-type cells, including rare formation of two viable 'twin' spores, rather than one within a single cell. By genetically modulating chromosome replication and septation, we can systematically tune the penetrance of each mutant fate. Furthermore, signalling and replication perturbations synergize to significantly increase the penetrance of twin sporulation. These results suggest a potential pathway for developmental evolution between monosporulation and twin sporulation through states of intermediate twin penetrance. Furthermore, time-lapse microscopy of twin sporulation in wild-type Clostridium oceanicum shows a strong resemblance to twin sporulation in these B. subtilis mutants...Together the results suggest that noise can facilitate developmental evolution by enabling the initial expression of discrete morphological traits at low penetrance, and allowing their stabilization by gradual adjustment of genetic parameters. Also, see press release, Caltech-led team shows how evolution can allow for large developmental leaps. A bit grandiose in headline.
Sunday, July 19, 2009
One of the "theories" I've had for a long time is that the smaller a proportion of a society's population atheists are, the stranger and more deviant they are going to be. A reason I came to this position is that read an account by an atheist American scientist who had some interactions with Soviet religious dissidents during the Cold War. His position was that in many ways American atheists and Soviet religious dissidents exhibited similarities in terms of personality, likely because they were generally not conformists. One of the peculiarities of the massive re-confessionalization of Russian society after the fall of the Soviet Union is the reality that these Communist era dissidents are now being marginalized in many congregations by recent converts who had a background as apparatchiks in the old regime, and were sometimes even actively involved in persecuting their current coreligionists! In any case, what about my hypothesis? Do I have any evidence for it? Not in any substantive manner. So I thought it might be interesting to look in the World Values Survey, naturally. How do attitudes of atheists and religious people vary within a society as a function of the proportion of each group?
I limited the sample to males, because men are more secular on average and exhibit more variance between nations. Additionally, because so many nations have very few atheists I put a lower bound of N = 20 for "convinced atheists." I mollified my own concerns about such a low N with the hope that if an N in a society is that low, the atheists may be strange enough indeed that their deviation from the social median may still swamp the noise. As before, the means for a class were calculated. So, the mean political self position of atheists and the religious is on a 1-10 scale. Below are are the charts for the results of a set of questions which exhibit a 1-10 level of agreement along a spectrum. The position is less important than the difference. First is a simple scatterplot which shows the attitudes of both the religious and atheists by nation. The expectation is a strong correlation between the religious and atheists, because most of the variation is naturally between nations. The second chart shows the difference between the two groups, "Religious persons" and "Convinced Atheists." I excluded those who were "Not religious" from the sample (so those who don't consider themselves religious, but neither are they professed atheists). Lastly, I plotted the difference between atheists and the religious as function of the ratio of religious to atheists. So, for example, the ratio of religious to atheists for Iraq is very high, atheists are a small minority (though to my surprise the N was large enough to stay above the threshold I put). In China the number of convinced atheists and religious are at parity, though those who are without religion and are not atheists are a plural majority. Looking at these results I'm going to withdraw my model. * For the "justifiable" questions 1 = never, 10 = always. * Competition is good = 1, competition is harmful = 10. * 1 = everything determined by fate, 10 = people shape their fates. * 1 = gov. more responsibility, 10 = individual more responsibility. * 1 = incomes more equal, 10 = we need larger differences for incentives. * 1 = private ownership should be increased, gov. ownership should be increased. * 1 = science makes world worse off, 10 = better off. * 1 = Left, 10 = Right.                                                    Labels: data, World Values Survey
Saturday, July 18, 2009
IQ Explains Some Of The Difference In Heart Disease Between People Of High And Low Socio-economic Status:
Authors of the study published in the European Heart Journal on 15 July...analysed data from a group of 4,289 former soldiers in the USA. They found that IQ explained more than 20% of the difference in mortality between people from socio-economically disadvantaged backgrounds compared to those from more advantaged backgrounds. Importantly, this was in addition to the classical, known risk factors for heart disease, such as smoking and obesity. When correlations between socioeconomic status and health outcomes emerge, generally there is an assumption that the differences are due to disparate access to health care, or, more vaguely to the mysterious effect of low social status on someone's health. Matt Ridley actually posited the second explanation in Genome. As noted above intelligence does not explain everything, but its role is unfortunately not considered all too often. If, for example, intelligence has some correlation with time preference, and time preference modulates one's risk calculus, the causal chain which might result in disparate health outcomes is obvious. In The Myth of the Rational Voter Bryan Caplan has a reasonable number of references to the literature which show that the more intelligent may not be particularly rational in any absolute sense, but they are far more rational than the conventionally dull in a relative sense. Labels: human biodiversity, IQ
Aziz pointed me to this article in Forbes, The New Great Game, which highlights the imperial aspect of the contemporary Chinese regime. It is important to emphasize that there is a striking disjunction between the manner in which the present spatial expanse of the Chinese state emerged, and the fiction which the modern Chinese state promotes to its citizens and abroad. The acquisitions which pushed China to the furthest extent in its history were achieved under the Qinq Dynasty in the 18th century. The Qing are also know as the Manchu dynasty, a pointer to the fact that they were outsiders. The Manchu elite took over the administrative apparatus of the previous Ming dynasty by the 17th century, but they were never wholly Chinese. The reality was that for much of the Qing dynasty China was part of the Manchu Empire. Though exemplary students of Chinese forms in their roles as Emperors of China, the Manchu rulers also remained warlords of the Manchu people, and it is in this capacity (albeit leveraging the resources of China proper) that they conquered the western territories, or pushed beyond Amur river to the north of Manchuria.
 To the left is an image which shows the geographical expanses of the major Chinese dynasties over time (earliest to left, the last bottom right). Only one dynasty rivals the Manchus in terms of the territory which they controlled, the Yuan, the Mongol dynasty. Like the Manchus the Mongols ruled China as part of a greater set of domains. Of the remaining the dynasties only the Tang had a robust and wide presence in Central Asia, but this hegemony evaporated by the second half of the Tang.Turkestan, Tibet and the lands to the north of the Amur (which were later extracted from the Manchu Empire by the Czars) were acquired due to the Manchu's greater cultural and geographic horizons than the Chinese (or, more accurately, a syngery between the enterprise of the nomad and the economic base of the Han Chinese). Like the Mongols the Manchus had a relatively good relationship with the lamas of Tibetan Buddhism, and the acquisition of Tibet occurred by way of their conflicts with the western Mongols (Oirat). The conquest of Xinjiang occurred as a byproduct of the Manchu involvement in intra-Mongol politics, as the Muslims of the Tarim Basin were chafing under the hegemony of the Dzungar Mongol confederacy. The drive to the north of the Amur would be a natural necessity to buffer the Manchu homeland against the expansion of the Russians into Siberia. Native Chinese dynasties, such as the Ming and Han, were hampered in their forays out of China proper due to their inability to maintain supply lines indefinitely and inflict any final defeat on nomadic populations which coul take advantage of the strategic depth offered by their vast ranges. It is notable that the Chinese dynasty which rivaled, though did not equal, the Manchu achievement in Central Asia were the Tang, of partial nomad background. The fact that China was part of a Manchu Empire mattered in concrete terms because many of the domains outside of China were administered separately (though later in the 19th century there was a trend toward more thorough integration as part of a modernization drive). The Turks of Xinjiang naturally would not consider themselves Chinese, since China was simply a subcomponent of a set of territories of which also included the city-states of the Tarim Basin. Similarly, the integration of Tibet into the Manchu Empire was cemented by the personal relationship between the lamas and the ruling Manchu, as well as religious affinities between the two peoples. China was a third party actor. All this makes more sense if you keep in mind the personal aspect of rule of hereditary kingdoms before the rise of the nation-state. George III, the king against who the American colonies revolted, was king of England, Wales and Scotland, Great Britain, as well as Ireland, the United Kingdom. Additionally, he was the Elector of Hanover. The fact that Hanover and the United Kingdom had the same ruler did not mean that these two administrative units were fused, on the contrary one of the concerns of the bureaucratic and aristocratic classes of both domains was that they not become excessively entangled in the international or domestic concerns of the other (the creation of Great Britain was favored by Scotland's ruling classes because they were excluded from many of the English colonies!). In 1837 Hanover's personal union with the United Kingdom ended because of the Salian law of inheritance of the throne. Now the connection between these two regions is simply a historical coincidence. Now imagine if England made a claim on Hanover based on the century of personal union between the two polities. This would be ludicrous. But in The New Chinese Empire the author recounts that several times during diplomatic visits by Russians Deng Xiaoping referred to the territories beyond the Amur which were lost in the 19th century as if they naturally belonged to the modern Chinese state. The reality of course is that these were conquests by the Manchus, and they were losses by the Manchus (though by the latter period the Manchus were far more Sinicized than they had been in the 17th century). For nationalistic and ideological reasons the Communist regime simply pretends as if the era of the Manchus was one where their domains were conceived of as a nation-state. Because the Chinese Empire entered onto the world stage in the 19th century in the post-Westphalian context the qualitatively non-Chinese aspects of rule in Xinjiang, Tibet or Manchuria were elided in terms of their relations with other states. Most Uighurs naturally are ignorant of these details of history. But these details of history have no doubt shaped the attitudes of ethnic minorities like Uighurs and Tibetans, for their integration into the Chinese state is naturally a thin veneer because it is a novel and new aspect to their experience. China proper emerged in its present form in larg part because of 2,000 years of institutional governance modeled on the precedents set forth in the Han dynasty; most of the Manchu acquisitions naturally lacked this background. The attempt to centralize the Manchu adminstrative apparatus in the 19th century was stillborn because of the death spiral of the dynasty. Only with the rise of the Communists did the Far West became an integral part of the nation. Note: China is a geographically diverse, but an ethnically homogeneous, "empire." In the Soviet Union Russians were only ~50% of the population, while in China the Han are ~90%.
Evolutionary Dynamics of Human Toll-Like Receptors and Their Different Contributions to Host Defense. Interesting stuff on inter-population variation in the discussion:
Our data show that TLR1, and more specifically the nonsynonymous T1805G variant (I602S), is the genuine target of positive selection detected in the TLR10-TLR1-TLR6 gene cluster in Europeans. First, TLR1 is ~2 times more diverse in non-African than in African populations, a pattern not compatible with the African origin of modern humans...This pattern has been observed only once among the 323 genes (0.3%) sequenced by the Seattle SNP consortium. Thus, the increased diversity observed in TLR1 among non-Africans probably results from ongoing hitchhiking between the selected allele and neutral variation at linked sites. Second, the 1805G (602S) mutation presents the highest level of population differentiation (FST = 0.54) of all SNPs located in this gene cluster...Third, among the three nonsynonymous variants composing the haplotype identified as being under positive selection in Europeans (H34, see Figure S5), only the TLR1 1805G (602S) variant has a remarkable impairment effect on agonist-induced NF-κB activation, showing a decreased signaling by up to 60%...These findings are consistent with previous studies showing that, homozygous, and to a lesser extent heterozygous, individuals for the 1805G allele present impaired TLR1-mediated immune responses after whole blood stimulation ...Taken together, it is tempting to speculate that an attenuated TLR1-mediated signaling, and a consequently reduced inflammatory response, has conferred a selective advantage in Europeans - a scenario that would explain the very high frequency (51%) of the "hypo-responsiveness" T1805G mutation in Europe. This observation raises questions about the possible evolutionary conflict between developing optimal mechanisms of pathogen recognition by TLRs, and more generally PRRs, and avoiding an excessive inflammatory response that can be harmful for the host. This looks to be the same area fingered earlier in Icelanders. Labels: Genetics
Friday, July 17, 2009
It is a rather robust cross-cultural finding that if there is a sex difference in religiosity, males will be less religious than females. Bryan Caplan has a theory about this. In any case, likely less surprising to readers is the generalization that males are more libertarian than females. Just as any random group of atheists is going to exhibit male surplus, meetings of self-identified libertarians usually seem to exhibit the same imbalance. Atheists and libertarians are both extreme cases of the distribution, and so it stands to reason that any mean difference would result in radically different representations several standard deviations away from the norm.
To explore this is a cross-culturally I looked at the WVS wave 5. Broke it down by sex & country, and looked at the following question: People should take more responsibility to provide for themselves vs The government should take more responsibility to ensure that everyone is provided for. The responses exhibit the range from 1-10, with one being "government should take more responsibility" and 10 being "people should take more responsibility." I computed the mean by weighting these values and the frequencies in each class of values. So if a category had a mean value of 6, that would indicate on average a more libertarian sentiment than a mean value of 4. In the total WVS sample the mean value for males is 5.7, and for females 5.6. In other words, men are somewhat more libertarian than women, but only slightly. Contrastingly there are almost 3 units in the range across countries. Below the fold are pairs of charts. The first simply displays the between sex difference for each country. If males are more libertarian in a given country the data are to the right of the chart, and if females are, the data are to the left. The scatter plots show the strong correlation in attitudes between sexes internationally. Broken down by sex:   Broken down by sex and limited to those over the age of 40:   Broken down by sex and limited to those under the age of 40:   Broken down by sex and limited to those on the political Right:   Broken down by sex and limited to those on the political Left:   It is interesting that the sex difference seems to diminish the political Left, but less so on the Right. Perhaps this is due to the fact that in much of the world the "Right" political party is really not that libertarian in any case, but more focused on social conservatism (e.g., Christian Democratic parties). Labels: politics
It's nice to see a bad idea demolished. And that's what Greven, et al. do in "More than just IQ." Their subtitle tells most of the story:
School achievement is predicted by self-perceived abilities (SPAs)--but for genetic rather than environmental reasons. So asking kids "Are you good at math and English?" is indeed a good way to find out who is good at math and English; and basic twin-study methods show that the answers to those questions are in fact genetically-driven, with heritability of 51% and family environment explaining 2%. Another family environment channel shot down. The authors drive that fact home: Despite the fact that not a single twin or adoption study has investigated the genetic and environmental etiologies of SPAs, researchers have cited environmental factors as a leading causal explanation for constructs related to SPAs, such as self-efficacy...and self-concept..... Moreover, one of the most established theories of SPAs assumes that the development of individual differences in SPAs is shaped primarily by parents' beliefs, expectations, attitudes, and behaviors... Of course, the bulk of the academic literature will surely go right on assuming that self-construct is driven by shared environment: "Surely, you don't mean to imply that an entire field of research was a waste of time, do you?" And in the policy and non-profit worlds these results won't stop those "Book in Every Home" campaigns. Alas.... More results: The genetic component of self-perceived abilities (SPA) is a good predictor of achivement, after you control for IQ. Even after you control for IQ and self-perceived ability, there's still a big genetic residual--about as big as IQ's genetic channel: So there are big genetic drivers of school achievement that don't fit into the two simple boxes of IQ and SPA. Sounds like an opportunity for some productive data-mining.... The big genetic residual fits in with the fact that a person's income is vastly more heritable than can be explained by the IQ channel alone. There are more things in gene expression, Horatio, than are dreamt of in your WAIS-R. Labels: Behavior Genetics, education, Flynn-baiting
Thursday, July 16, 2009
 In recent years, the genetic mechanisms by which humans have generated massive phenotypic diversity in dogs have started to be uncovered. We now know, for example, much about the genetics of pigmentation in dogs, and a major gene controlling body size. This week, another phenotype--the short, stubby legs of some dog breeds (see right)--has been revealed to have a simple, but interesting genetic basis. The authors mapped the short leg phenotype to a small region on chromosome 18; further analysis revealed that the probable causal mutation is the insertion of a transcriptionally-active processed (ie. intronless) retrotransposed copy of the FGF4 gene. How this change leads to the phenotype itself is unknown, but understanding the mechanism will likely lead to some interesting biology. Labels: Genetics
Wednesday, July 15, 2009
Randall points me to a paper, Brain Regions for Perceiving and Reasoning About Other People in School-Aged Children:
Neuroimaging studies with adults have identified cortical regions recruited when people think about other people's thoughts (theory of mind): temporo-parietal junction, posterior cingulate, and medial prefrontal cortex. These same regions were recruited in 13 children aged 6–11 years when they listened to sections of a story describing a character's thoughts compared to sections of the same story that described the physical context. A distinct region in the posterior superior temporal sulcus was implicated in the perception of biological motion. Change in response selectivity with age was observed in just one region. The right temporo–parietal junction was recruited equally for mental and physical facts about people in younger children, but only for mental facts in older children. The sample included 7 girls and 6 boys. No mention of sex differences. Though perhaps the methods were too coarse. In any case, aspiring neuroimagers of social intelligence just need to go to a Perl Mongers meeting to recruit cognitive outliers! Labels: Psychology
How soon businesses forget how loony the loony ideas of yesterday were
posted by
agnostic @ 7/15/2009 10:37:00 PM
Mathematical models of contagious diseases usually look at how people flow between three categories: Susceptible, Infected, and Recovered. In some of these models, the immunity of the Recovered class may become lost over time, putting them back into the Susceptible class. This means that if an epidemic flares up and dies down, it may do so again. If we treat irrational exuberance as contagious, then we can have something like a recurring exuberant-then-gloomy cycle within people's minds. That is, people start out not having strong opinions either way, they get pumped up by hype, then they panic when they figure out that the hype had no solid basis -- but over time, they might forget that lesson and become ripe for infection once more.
I'm in the middle of Stan Liebowitz's excellent post-mortem of the dot-com crash, Re-thinking the Network Economy, and in Chapter 3 he reviews the "first mover wins" craze during the tech bubble. According to this idea, largely transplanted into the business world from economists who'd already spread the myth of QWERTY, the prospect of lock-in was so likely -- even if newcomers had a superior product -- that it paid to rush your product to the market first in order to get the snowball inevitably rolling, no matter its quality. The idea was bogus, of course, as everyone learned afterward. (There were plenty of examples available during the bubble, but the exuberance prevents people from seeing them -- Betamax was before VHS, WordPerfect was before Microsoft Word, Sega Genesis was before Super Nintendo, etc. And there were first-movers who won, if their products were highly rated. So, when you enter doesn't matter, although quality of product does.) But when I looked up data on how much the media bought into this idea, I was surprised (though not shocked) to see that it was resurrected during the recent housing bubble, although it has been declining since the start of the bust phase. Below the fold are graphs as well as some good representative quotes over the years. First, here are two graphs showing the popularity of the idea in the mainstream media. The first is from the NYT and controls for the overall number of articles in a given year. (I excluded a few articles that use "first mover" in reference to the Prime Mover god concept in theology.) I don't have the total number of articles for the WSJ, so those are raw counts. Still, the pattern is exactly the same for both, and it very suggestively reflects the two recent bubbles:   The first epidemic is easy enough to understand -- after languishing in academia during the mid-1980s through the mid-1990s, the ideas of path dependence, lock-in, and first-mover advantage caught on among the business world with the surge of the tech bubble. When it became apparent that the dot-coms weren't as solid as was believed (to put it lightly), everyone realized how phony the theory supporting the bubble had been. Here's a typical remark from 2001: WHEN they were not promoting the now-laughable myth of ''first mover advantage,'' early e-commerce proponents proffered the idea that self-service Web sites could essentially run themselves, with little or no overhead. But clear-headedness eventually wears off, and when another bubble comes along, we can't help but feel exuberant again and take another swig of the stuff that made us feel all tingly inside before. Here's a nugget of wisdom from 2006: Media chieftains may be kicking themselves a few years from now because they didn't step up to pay whatever it took to own the emergent first mover in online video.And a similar non-derogatory, non-ironic use of the phrase from 2007: For the current generation of Internet applications, sometimes referred to as "Web 2.0," the data collected from users is the true source of competitive advantage. And the first movers, the companies that understand and apply this insight, have services that get better fast enough that their competition never catches up. Thankfully we've been hearing less and less of this stupid idea ever since the housing bubble peaked, and at least the most recent peak was lower than the first one, but we can still expect to hear something like this during whatever the next bubble is. Note that the first-mover-wins idea wasn't even being applied primarily to real estate during the housing bubble -- the exuberance in one domain carried over into a completely unrelated domain where it had flourished before. So, if you're at all involved in the tech industry, be very wary during the next bubble of claims that "first mover wins" -- it wasn't true then (or then, or then), and it won't be true now. Labels: Economics, History, Technology
Tuesday, July 14, 2009
In case you don't know, the Cognition & Culture group blog is of some interest. One of the contributors is Dan Sperber, who I interviewed a few years ago. Sperber et al. work within the naturalistic paradigm in cultural anthropology. I like to think of it as anthropology that comes not to praise gibberish, but bury it. In all likelihood the models are mostly wrong, but that's a feature. In much of American cultural anthropology the models can't even be wrong because of the incredibly obfuscatory word-play.
Labels: culture
Rod Dreher has a post about the The problem of pornography. My question: how is porn fundamentally different from fantasizing? Is it because of the shift toward bizarre fetish porn which rescales your perceptions of normal? I'm generally skeptical of anecdotal arguments about how porn is "changing everything." Because of my interest in Transhumanism and the Singularity I have run into people whose sexual outlets are skewed toward the virtual as opposed to the physical, and all seem to prefer the latter over the former. I won't even get into the issues of causality when it comes to all the bizarre things which known serial killers engage in.
Also, Rod makes a reference to "Late-Roman" culture. The allusion is common among many Christian conservatives, and I think I know what he's suggesting, that our society is becoming decadent, amoral, lacking spiritual values (he's made the allusion multiple times). Here's my problem: this doesn't comport at all with even a cursory reading of Roman history that you could gain from Wikipedia. The Late Roman period was one of the Chrisitanization of the Empire, and a resurgence of moralism among both pagans and Christians. Much of the Western Empire shifted more toward primary production and the modest economies of scale, and the specialization which allowed for the long distance trade of basic consumer and luxury goods diminished. In the East the Empire did not fall, but became progressively more Christian in its identity, as evidenced by the Christian moral ethical influence on the codification of Roman law during the reign of Justinian. The secular intellectual pursuits of the elite gave way to an emphasis on religious piety, study and endowment of monasteries and churches (see the life of Cassiodorus). In fact the revisionists who followed in the wake of Peter Brown and have reinterpreted the Decline and Fall of the Roman Empire as a Transformation of the Roman World point to the importance of Late Antiquity in setting the groundwork for the Christian civilization of Medieval Europe. "Late-Rome" was the time of the flourishing of Augustine and Ambrose in the West, the Cappadocian Fathers in the East who are so important in the Greek Christian tradition. In general the revisionists might not deny the decline in material standards, in median affluence, but they emphasize the richness of cultural production, particularly religious cultural production. Were public morals at the peak of the Empire such a high watermark? Augustus' own family was wracked with debauchery to the point where he banished his own daughter. Though there were rumors about Tiberius, the perversions of Caligula and Nero are famous, and even the relatively innocuous Claudius married his niece. For those of you not up on your emperors, this is within the first century of the Empire. The Antonine Emperors were known to be moderate and virtuous in comparison to the prurience of the Julio-Claudians or the tyranny of Domitian, but Hadrian was certainly a pederast, and there are rumors about Trajan as well. Commodus of course made Andrew Johnson seem a model of sobriety and gravitas (this is the second century of the Empire). At its peak the the Roman Empire was pagan, pluralist in religion and philosophy, and many of the autocrats flaunted personal morals which were in sharp contradiction to Christian virtue. It was relatively affluent (though we're talking percentages on the margin of median wealth I suspect, not multiplicative) and militarily robust. In the later phase the Empire imposed religious homogeneity on the elites in the form of Christianity, and the sort of public virtue which Augustus or Marcus Aurelius might have smiled upon became baked-into-the-cake of the ideology of the proto-monarchs which the emperors had become (although women such as Pulcharia and Theodora were generally the enforcers). Bread & circuses might have persisted in Rome up until the Gothic Wars, across much of the Empire there was a shift toward self-suffuciency and primary production. Dare I say, the Empire was becoming more "crunchy"? As I said, the analogy to the Late Roman Empire has rhetorical force. Everyone knows what the allusion is meant to indicate. The problem emerges when people think that they can then start looking to Late Antiquity as an analogical model to make predictions about the future because of tight correspondences of conditions. Since those correspondences actually don't exist, rather, if there were material and moral variations across the span of the time of the Roman Empire they go in an inverse direction from the rhetoric, all you do is mess up your model of how the world works. Since Rod Dreher converted to the Eastern Orthodox Church he has no excuse of being ahistorical and fixated on abstract concepts of primitive salvation. The Late Roman Empire was the midwife for the greatest revolution in the history of the world from the perspective of a Catholic or Orthodox Christian,* so perhaps he should reconsider his sloppy use of the analogy. In the short term these rhetorical tactics are useful, but in the long term truth matters and errors which propagate through the chain of reasoning can be hard to filter out. Note: If you want some evidence of the decline in material affluence as a function of time, see The Fall of Rome: And the End of Civilization and Framing the Early Middle Ages: Europe and the Mediterranean, 400-800. A narrative of the cultural genius of the Late Roman period can be found in The Rise of Western Christendom: Triumph and Diversity, A.D. 200-1000. * Some Protestant radicals are skeptical of the influence of Late Antiquity because they believe that the Church took a wrong turn in its institutionalization and association with temporal powers.
Monday, July 13, 2009
More results for the WVS 2005. I added some demographic data by province as well. I want to pool the "northern" and "southern" provinces soon. I'd appreciate Chinese readers input on the categories if there isn't something straightforward.
                      Labels: China
QWERTY-nomics debate thriving 20 years after "The Fable of the Keys"
posted by
agnostic @ 7/13/2009 02:05:00 AM
In 1990, Stan Liebowitz and Stephen Margolis wrote an article detailing the history of the now standard QWERTY keyboard layout vs. its main competitor, the Dvorak Simplified Keyboard. (Read it here for free, and read through the rest of Liebowitz's articles at his homepage.) In brief, the greatest results in favor of the DSK came from a study that was never officially published and that was headed by none other than Dvorak himself. Later, when researchers tried to devise more controlled experiments, the supposed superiority of the DSK mostly evaporated.
Professional typists may have enjoyed about a 5% faster rate, or maybe not -- despite the conviction of the claims you hear, this isn't a well established body of evidence, such as "smarter people have faster reaction times." Moreover, most keyboard users aren't professional typists, and the vast bulk of their lost time is due to thinking about what they want to say. Therefore, the standardization of the QWERTY layout is not an example of our being locked in to an inferior technology. Which isn't to say that the QWERTY layout is the best imaginable -- but certainly not a clearly inferior layout compared to the DSK. While Liebowitz and Margolis may have hoped that their examination of the evidence would have thrown some cold water on the "lock-in to inferior standards" craze that had gotten going in the mid 1980s, with QWERTY as the proponents favorite example, the idea appears too appealing to academics to die. (Read this 1995 article for a similar debunking of Betamax's alleged superiority over the VHS format.) Liebowitz appeared on a podcast show just this May having to reiterate again that the standard story of QWERTY is bogus. To investigate, I did an advance search of JSTOR's economics journals for "QWERTY" and divided this count by the total number of articles. This was done for five four-year periods because it's not incredibly popular in any year, and that creates more noise in a year-by-year picture. I excluded the post-2004 period since there's typically a 5-year lag between publication and archiving in JSTOR. This doesn't show what the author's take is -- only how in-the-air the topic is. With the two major examples having been shown to not be examples of inferior lock-in at all, you'd think the pattern would be a flaring up and then dying down as economists were made aware of the evidence, and everyone can just leave it at that. But nope:  Note that the articles here aren't the broad class discussing various types of path dependence or network effects, but specifically the kind that lead to inferior lock-in -- as signalled by the mention of QWERTY. I attribute the locking in of this inferior idea to the fact that academia is not incentivized in a way that rewards truth, at least in the social sciences. Look at how long psychoanalysis and Marxism were taken seriously before they started to die off in the 1990s. Shielded from the dynamics of survival-of-the-fittest, all manner of silly ideas can catch on and become endemic. In this case, the enduring popularity of the idea is accounted for by the Microsoft-hating religion of most academics and of geeks outside the universities. For them, Microsoft is not a company that introduced the best word processors and spreadsheets to date, and that is largely responsible for driving down software prices, but instead a folk devil upon which the cult projects whatever evil forces it can dream up. Psychologically, though, it's pretty tough to just make shit up like that. It's easier to give it the veneer of science -- and that's just what the ideas behind the QWERTY and Betamax examples were able to give them. Overall, Liebowitz's work seems pretty insightful. There's very little abstract theorizing, which modeling nerds like me may miss, but someone's got to take a hard-nosed look at what all the evidence says in support of one model or some other. He and Margolis recognized how empirically unmoored the inferior lock-in literature was early on, and they also saw how dangerous it had become when it was used against Microsoft in the antitrust case. [1] He also foresaw how irrational the tech bubble was, losing much money by shorting the tech stocks far too early in the bubble, and he co-wrote an article in the late 1990s that predicted The Homeownership Society would backfire on the poor and minorities it was supposed to help. (Read his recent article on the mortgage meltdown, Anatomy of a Train Wreck.) Finally, one of his more recent articles looks at how file sharing has hurt CD sales. Basically, he details everything that a Linux penguin shirt-wearer doesn't want to hear. [1] Their book Winners, Losers, and Microsoft and their collection of essays The Economics of QWERTY attack the idea from another direction -- showing how the supposed conditions for lock-in or market tipping were met, and yet time and again there was turnover rather than lock-in, with each successive winner having received the highest praise. Labels: culture, Economics, History, Technology
Sunday, July 12, 2009
 The comments below in regards to Chinese regionalism were informative. But for those of us without a more direct connection with China works can be wanting, so I thought looking at the World Values Survey would be interesting as there is a regional breakdown within it. Below the fold are a series of barplots where the different segments equal 100%. As you can see I took the first response and sorted by that. The sample sizes for some of the provinces are not high. Just ignore Chongqing where N = 1. But I am curious if Chinese readers are note regional differences just by visual inspection. Unfortunately I assume most non-Chinese (like myself) immediately know the location of only a few provinces, so the visual impact will be diminished for us. I will have a follow up post going down the list of WVS questions tomorrow. On the charts referring to "neighbors," those are mentions of people they would like not to live next too. On the freedom question, it refers to how much freedom people feel they have in their life. You can go to the WVS site to clear up confusions in the legend...I produced the charts quick & dirty from my own copy of the WVS data set. In the future I'll probably combine some of the provinces into macroregions (e.g., north, south, west) to increase sample size, but that's for later. The only thing I wonder, what's up with the wide variance in mentioned fear of the gay?
                                 Labels: China
Robert Frank is promoting his idea that Charles Darwin will become more important than Adam Smith as an intellectual forebear of future economics in The New York Times. That is fine as it goes but I suspect that the bigger issue in the sciences of humanity is that there will be problems with relying on only one disciplinary framework and one general model. For example Frank points out that evolutionary fitness is generally conceived of in a relative sense (population mean fitness being the baseline), but the same dynamic crops up in neuroscience due to biophysical computational efficiencies from relative heuristics as opposed to a laundry list of absolute fixed preferences. R. A. Fisher famously wished to lay the seedbed for a thermodynamics of evolution in The Genetical Theory of Natural Selection. Whether one can envisage this in evolutionary genetics, it seems even less likely in the human sciences, at least to the extent of making a generalization which is not trivial. The rut which orthodox evolutionary psychology has found itself in is probably due to this assumption that our species is at some biobehavioral equilibrium due to an exceedingly unrealistic model of evolutionary dynamics.
Labels: Behavior Genetics, Behavioral Economics, Economics
Friday, July 10, 2009
Update: After the comments I'm rather sure that though the WSJ piece was well written and generally right on specific facts (excepting the fact that Sun Yat-sen was not born outside of China as the author claimed) it is grossly misleading. I have no idea if the author had some agenda to push, but it does make me wonder as to how many boring articles the WSJ rejected only to accept the somewhat bizarre claims articulated in the piece they published. End Update
The WSJ has a long article up, China's Ethnic Fault Lines, which emphasizes the difference between Chinese speakers from various regions, who are all notionally "Han," though those of the south may refer to themselves as "Tang" in remembrance of the dynasty which witnessed a shift of China's center of gravity south.* It's a long piece with a lot of facts, but I have feeling that it tries too hard to suggest that the Han Chinese identity is a recent construction and that Cantonese and Fujianese have submerged separatist inclinations. From what I know those from south of the Yangtze have been essential players in the Chinese bureaucratic state for 1,000 years, so even hinting at an analogy with the separatism of Turks and Tibetans from western China is grossly misleading. The mercantile people of south China, especially Fujian, have long had to battle a central government, generally based out of the plains of northern China, which would have preferred that they focused on primary production. But despite this deep division in worldviews young men from Fujian were well represented in the bureaucracy. More recently both Mao and Deng Xiaoping were from south of the Yangtze. There are some tensions between people from different parts of China, as there are in any country, but the author seems a very knowledgeable person who might be leading some astray here by conflating expected regional & linguistic tensions with atavistic nationalisms submerged (I've seen some ethnic shell games before). This all matters because the subtext of the piece is that China is more diverse than you think, and a possible near future powder keg. 91% of Chinese are Han, but if you look at mutually unintelligible dialects the index of diversity can crank up (what a language or a dialect is is to a large extent political; e.g., Croation vs. Serbian). On the other hand, if the glass is mostly full and you ignore dialect diversity for the purposes of separatist movements, and note that the huge increase in ethnic minorities in China to 9% is probably part of the same phenomenon as the doubling of Native Americans in the USA between 1990-2000, China looks rather homogeneous (the "new" Native Americans in the USA are probably likely to be less activist about their rights and identity than those who were Native American for many censuses in a row). Instead of a north-south dynamic the bigger issue seems to be the interior-coast economic chasm, which is obviously cuts across the Han vs. Tang division mentioned in the piece. On the specific issue of the real nationalisms in China's west it seems Xinjiang and Tibet are going to have different futures. I've been hearing that Xinjiang is 40% Han for the past 15 years, so I suspect they're undercounting so as not to exacerbate resentments. With demographic marginalization the future is set & sealed (many of south China's non-Han groups exist as demographic islands surrounded by Han majorities). Tibet on the other hand is a different case because it seems that non-Tibetans experience enough physical discomfort that no one will want to settle down permanently. Extended occupation instead of absorption will be necessary so long as the locals are not quiescent (Lhasa is as 12,000 ft, 3,650 meters!). I would like to hear from Chinese readers or those who live in China as the plausibility of the claims of the article above. Note: The World Values Survey can be broken down by language spoken at home. I see no great difference between dialect groups and Mandarin speakers in regards to national pride. Also, here are supposed numbers for the number of people in China who speak Mandarin: Just over 53% of the population of China or 690 million people are able to speak Mandarin, according to the Xinhua news agency. In China's cities, about 66% speak Mandarin, while only 45% speak it in the countryside. Around 70% of people between the ages of 15 and 29 speak the language, while only 30% of those over 60 can speak it. The numbers seem a littler lower than others online. Additionally, Mandarin is not a regional identity, while in contrast Cantonese is a dialect with a strong regional association. Here is a map of dialect groups. * The Han was China's first robust dynasty and established in many ways the patterns of Chinese culture which persist down to the present, and was also the institutional model for its government down to ~1900. The Tang was China's second great dynasty, and pushed the state's boundaries both south and west, and to a great extent was the period when southern China was sinicized. Labels: China
As nation gains, 'overweight' is relative:
The little number on the tag on a pair of pants that indicates size can mean a lot to a person, and retailers know it. When I was in high school one particularly dumb classmate was very excited to learn that one's weight is marginally lower at higher elevations. She gave me a blank look when I pointed out that mass remains the same. I tactfully left out the fact that there wouldn't be a change in volume or surface area either.... H/T Michelle Cottle, who lets slip that she has remained the same size and shape since high school. Labels: Psychology
While skimming today's UK newspapers I noticed this report in the Daily Telegraph on research into the evolution of 'tit-for-tat' reciprocal altruism. I haven't checked out the original research, but thought I would post the story for general interest.
Thursday, July 09, 2009
So Francis Collins, as expected, will be nominated to be the next head of NIH. From the NY Times:
[P]raise for Dr. Collins, 59, was not universal or entirely enthusiastic. Dr. Georges C. Benjamin, executive director of the American Public Health Association, called Dr. Collins's selection a "reasonable choice."I think that's about right--this is a reasonable choice.
Chromosomal Problems Affect Nearly All Human Embryos: Discovery May Explain Low Fertility Rates In Humans:
For the first time, scientists have shown that chromosomal abnormalities are present in more than 90% of IVF embryos, even those produced by young, fertile couples. Ms Evelyne Vanneste, a PhD student in the Centre for Human Genetics and the University Fertility Center, Leuven University, Belgium, told the 25th annual conference of the European Society of Human Reproduction and Embryology on July 1st, that the surprising finding meant that current techniques used in preimplantation genetic screening (PGS), where embryos are screened genetically in order to select the best embryo for transfer, do nothing to improve pregnancy and live birth rates. Indeed, it can lead to potentially viable embryos being discarded, she said. The exact proportion of fertilizations which end in spontaneous abortion (or lack of implantation) seems rather sketchy from what I can tell, but it's very high. In The Cooperative Gene Mark Ridley suggests that the very high rates of spontaneous abortion among humans is one reason he is not particularly worried about increased genetic load, a prime concern of W. D. Hamilton. I assume he believes that the proportion of spontaneous abortions would simply increase for individuals who have a high mutational load. Hamilton worried about the fact that many more humans lived to reproduce than would have in the past, so that natural selection was no longer operative. Ridley is suggesting that actually the power of selection may simply be transferred to the gestational stage. One interesting idea would be to see if different populations have different rates of spontaneous abortion. How one would get a precise measure of this, I don't know. Labels: Genetics
Tuesday, July 07, 2009
Anti-Irish caricatures, the hypothesis that some races contain little intra-race variation, and how economists keep arguing--normatively and positively--for the rough equality of humankind: It's all in Peart and Levy's book The Vanity of the Philosopher.
The book is highly recommended to GNXPers with any interest in the complicated historical relationship between genetics and social science. The major value-added comes from the oft-ignored tension between economic theorists and evolutionary theorists. Well, that and the cartoons. The book builds on Levy's earlier work How the Dismal Science Got its Name. A free, abbreviated version of that story is here, and is wiki'd here. For some HBD newbies, the best part of Vanity will be the discussion of the Irish: In the early days of Darwinism, the people of the Emerald Isle were Exhibit A (or B) of an inferior race. Peart and Levy have a great discussion of how 19th century intellectuals hoped the Irish to evolve to become as well-mannered as, say, the English. And in the 19th century, whenever attacks on the Irish started up, attacks on abstract, unrealistic, ahistorical economic theory were rarely far behind. Funny, that... Oh, one more reason to take a look at Vanity: Peart and Levy slide the knife into Charles Dickens, a sight always to be relished. Labels: Economics
Monday, July 06, 2009
Econlog has been having a running debate between Bryan Caplan and Arnold Kling on the relationship between politics and personality.
Labels: Behavior Genetics
Here is a case for Razib to add to his collection of families showing genetic segregation for skin colour and other biodiverse traits. The mother is white and the father mixed-race, while the three children are said to range in appearance from black to white. Actually two of them look to me predictably mixed-race, but the third does look quite white. This is genetically conceivable (sorry for the unavoidable pun), but in such cases I always think a more humdrum explanation should first be excluded.
Sunday, July 05, 2009
More porn does not lead to less rape -- or to more either
posted by
agnostic @ 7/05/2009 09:21:00 PM
There's a post on porn and rape that's making the rounds (among the blogs I read, at Half Sigma and Roissy so far). The author claims to show that a greater availability of pornography is associated with lower rape rates. But it is not -- nor are the two directly related. They simply appear unrelated altogether.
First, the original post's author is not an idiot; he just made an honest mistake in getting his crime data. (And he is right in his side-point about how moronic feminists are when they suggest that rape has little to do with meeting the guy's sexual urges.) But let's focus on what the crime data say. The Bureau of Justice Statistics website has a page of summary statistics that includes the graph in his post that shows what looks like a decline in the rape rate from the early-mid 1970s until today. Those data appear to be from the National Crime Victimization Survey, and one drawback here is that minors are often questioned in the presence of their parents or guardians. They're much less likely to report something embarrassing and painful as rape when the adults are there, especially if it was a family member or acquaintance of the family, as is typical. And young females are the most at risk. The definition of rape there seems too broad also, including attempted rape and psychological intimidation -- what people really have in mind when they hear "rape" is someone using physical force to gain sexual access to another person. Luckily, though, the BJS also has data on the forcible rape rate ("real" rape), and this series goes back even further than the NCVS data -- back to 1960. What do these data say? If you're a regular reader, you already know because I've reviewed the change in violent crime and forcible rape rates before. Go to that post to see the graph and get the details. In brief, there was a sharp rise from about 1964 through 1992 and a decline thereafter. What was the change in porn availability from 1960 to 2006? I've reviewed that topic too. Again, go there for the graphs and details. Looking just at Playboy to stand in for pornography generally, its circulation in 1960 was about 1 million and shot up to 7.2 million at its peak in 1972, dropping to 3 million by 1987, where it has stayed since. Population size isn't the main factor here since the US population did not multiply by 7 between 1960 and 1972. There was an explosion in Playboy circulation, and even through the 1980s it was still 3 times as high as in 1960. Therefore, from 1960 to 1972, there was a surge in porn availability and a surge in the forcible rape rate. This much of the data contradicts the "more porn, less rape" idea. But Playboy circulation dropped sharply from 1973 to 1987, and that didn't cause the rape rate to drop. Its circulation has remained pretty steady since 1987, while the rape rate has steadily fallen since 1992. There are other data in the above post from the General Social Survey on what percent of men have watched an X-rated movie in the past year. Again there are no clear patterns that suggest an association with the forcible rape rate. If anything, the availability of porn has increased since the mid-late 1990s with the adoption of the internet. That suggests the "more porn, less rape" idea since rape was falling -- but it had peaked in 1992, about a half-decade before most guys had easy access to internet porn. Putting all of the data together, it doesn't look like there's a relationship at all between availability of porn and the forcible rape rate. It's trivial to choose a time period in which your preferred hypothesis pans out, but looking at the big picture is always more revealing. In this case, we discover a big let-down -- neither side is right, and rape has little to do with porn. Debates like "porn and rape" or "poverty and crime" serve mostly as a full employment plan for gasbags. What if the two things aren't related in the first place? Well, that's a pretty boring debate -- way to rain on our parade.
Nicholas Wade (guesting posting for John Tierney) points to a set of papers in this week's Nature reporting large genome-wide association studies of schizophrenia. The main upshot of the papers is that variants in the MHC region influences susceptibility to schizophrenia. This region influences susceptibility to a number of autoimmune diseases, so the association is suggestive evidence that schizophrenia as well has an autoimmune component.
Outside of the MHC, however, there are few convincing signals of association. One interpretation of this might be that there are simply no other common polymorphisms that influence risk of developing schizophrenia. One of the groups, however, set out to test whether this was the case. They took thousands of the top associated SNPs--none of them individually showing a strong association with the disease--and assembled them into a genotypic score for predicting whether an individual has schizophrenia. And indeed, using these thousands of markers, they were able to do significantly (in the statistical sense, not really in the practical sense) better than random at classifying individuals as schizophrenic or not from genotype data alone. Thus, the aggregate effect of thousands of polymorphisms impacts the development of this disease. What is the practical significance of this? In terms of treatment or drug development, there is essentially none. But it does suggest that there will be no "silver bullet"--copy number polymorphism, rare variants, or what have you--that will solve schizophrenia genetics. Labels: Genetics
Saturday, July 04, 2009
Enjoy the fireworks & the heat.
Friday, July 03, 2009
I was listening to Marketplace the other day and Kevin Hassett delivered a commentary combining economics with a revisionist evaluation of the American Revolution. Hassett's argument seems to be that the Revolution, which was notionally predicated on taxation without representation, will in the long run be a historical blip of no consequence as the United States converges upon the same tax and spend structure as the United Kingdom. From this convergence of tax and expenditure structures Hassett infers an eventual closing of the $10,000 GDP per capita gap between the United States and the United Kingdom. What therefore was the point of breaking away if 200 years later the USA is going to be so similar to the United Kingdom?
There are many ways to critique this sort of analysis, but there are two major issues that I jumped out for me. First, 200 years is not a trivial interval of time, especially when taking into account the large numbers of Americans who lived between then and now. To view economic history as convergence toward equilibria as a few parameters are modulated at some point in the future seems worthless, just as pointing out that the Sun will go nova, or that the universe may be doomed to heat death. There is a big difference between asserting that the GDP per capita gap will close within 10 years, and within 100 years. Tractable and elegant macroeconomic models may be mostly junk over the short term, but I'm pretty sure that they're total junk over the long term. Inferences from stylized facts may provoke, but spare me the assumption that that the error bars of projections aren't so huge as to make them useless even for government work. Second, it isn't as if the only things that separate the United States and the United Kingdom are institutional frameworks. Even within the United States there is quite a bit of regional variation in culture. Perhaps Hassett would say that specific variation in the instantiation of human capital is totally irrelevant, but most people wouldn't assume that as a given. Secondarily there is a sense here that historical contingency doesn't exist, that there is no path dependence in economic development. So the 200 year interval whereby the American Revolution served as an exogenous shock which tore the thirteen colonies out of the British Empire had no significant effect by shifting initial parameters in a manner which might "lock in" a bias toward some developmental paths as opposed to others. But evaluated over a long enough interval all historical events can be marginalized as futile acts against the trendline, whatever it is. Instead of using an abstract framework riddled with assumptions that many people would find laughable, why not go the route of pointing to the nature of the British settler colonies which did not revolt, but eventually became independent? Obviously Australia, Canada and New Zealand are different in myriad ways from the United States, but are the comparisons more strained than the model that Hassett posits?
Thursday, July 02, 2009
In the new issue of The New Yorker, Malcolm Gladwell reviews some book about using the appeal of FREE to grow your business. This is supposed to apply most strongly to information, so that as more and more of a firm's product / service consists of information, the more it can use the appeal of FREE to earn money.
What both Gladwell and the reviewed book's author, Chris Anderson, don't seem to realize is that the appeal of FREE creates pathological behavior. Gladwell even cites a revealing behavioral economics experiment by Dan Ariely: Ariely offered a group of subjects a choice between two kinds of chocolate -- Hershey's Kisses, for one cent, and Lindt truffles, for fifteen cents. Three-quarters of the subjects chose the truffles. Then he redid the experiment, reducing the price of both chocolates by one cent. The Kisses were now free. What happened? The order of preference was reversed. Sixty-nine per cent of the subjects chose the Kisses. The price difference between the two chocolates was exactly the same, but that magic word "free" has the power to create a consumer stampede. In other words, FREE caused people to choose an inferior product more than they would have if the prices were both positive. Thus, in a world where there is more FREE stuff, the quality of stuff will decline. It's hard to believe that this needs to be pointed out. And again, this is not the same as prices declining because technology has become more efficient -- prices are still above 0 in that case. FREE lives in a world of its own. If you're only trying to get people to buy your target product by packaging it with a FREE trinket, then that's fine. You're still selling something, but just drawing the customer in with FREE stuff. This jibes with another behavioral economics finding -- that when two items A and B are similar to each other but very different from item C, all lying on the same utility curve, people ignore C because it's hard to compare it to the altneratives. They end up hyper-comparing A and B since their features are so similar, and whichever one is marginally better wins. So if you have three more or less equally useful products, A B and C, where B is essentially what A is, just with something FREE thrown in, people find it a no-brainer to choose B. An exception to the rule of "FREE leads to lower quality" might be the products that result from dick-swinging competitions, where the producer will churn out lots of FREE stuff just to show how great they are at what they do. They're concerned more with reputation than getting by. Academic work could be an example -- lots of nerds post and critique scientific work at arXiv, PLoS, as well as the more quantitatively oriented blogs. But in general, you can imagine the quality level you'd enjoy from a free car or an all-volunteer police force. Even sticking with just information, per Chris Anderson, look at what movies you can download without cost on a peer-to-peer site or whatever -- they mostly all suck, being limited to the library of DVDs that geeks own. Sign up for NetFlix or a similar service, and you have access to a superior library of movies, and it hardly costs you anything -- it's just not FREE. Ditto for music files you can download cost-free from a P2P site vs. iTunes, or even buying the actual CD used from Amazon or eBay. Admittedly I don't know much about computer security, but just by extending the analogy of a voluntary police force, I'd wager that security software that costs anything is better than FREE or open source security software. To summarize, though, Gladwell's discussion about FREE misses the most important part -- it tends to lower quality. I don't want to live in a word of lower quality of items that aren't of major consequence, and (hopefully) the people in charge of high-consequence items like the police and my workplace's computer security will never be persuaded to go for FREE crap in the first place. This aspect alone answers the question he poses in the sub-headline, "Is free the future?" However, wrapping your brain around the idea that FREE tends to lower quality is discordant with a Progressive worldview, which explains why Gladwell just doesn't get it. Labels: Behavioral Economics, Economics, Media, Technology
Catfish plan risks trade war:
It looks like catfish, it tastes like catfish, and it acts like catfish. It doesn't taste like catfish.
Wednesday, July 01, 2009
It's hard out there being a non-Indo-European speaker in Europe
posted by
Razib @ 7/01/2009 02:33:00 PM
Matt Yglesias points out that in terms of suicide rates Finland is a Scandinavian outlier, and clusters with Japan and Korea. But interestingly, there's another European nation which is even more suicidal than Finland. Hungary. Below the fold are the data for the OECD nations....
 Labels: Finn baiting
I'm still working on a post about Darwin's theories of heredity, but I need to re-read the 900 pages of Variation of Animals and Plants Under Domestication first, so it may take me some time.
Meanwhile, and irrelevant to anything, I see that one of my favourite artists, Imogen Heap, has a new album coming out soon(ish). Here is a video trailer. Also check out Imogen's delightful video blogs, all available on YouTube. |
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