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gwern branwen
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John Keats (1795-1821). Extracts from Hyperion: Oceanus. T. H. Ward, ed. 1880-1918. The English Poets
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+Matt Restko : I've always felt that if you're going to write an agenda'd hit piece, you owe it to your readers to at least pretend it's a balanced presentation of experience-as-lived. They deserve at least the fig leaf.

Also, the least curious journalist-undercover I've read in a long time. Almost zero occasions of, "I dislike this bit; why don't I ask someone why it's this way? Might there be a reason?"
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Rare genetic mutations implicated in >13% of unexplained cardiac deaths. Makes one wonder how much of the long tail of deaths are due to rare variants, and how much of a benefit there would be to erasing the ~80k mutations everyone carries... (Population genetics rule: rare variants are more harmful than common variants; and 1 harmful mutation, 1 reproductive death to purge it from the population.) Very cool application of genetics.

"A Prospective Study of Sudden Cardiac Death among Children and Young Adults", Bagnall et al 2016:

"BACKGROUND: Sudden cardiac death among children and young adults is a devastating event. We performed a prospective, population-based, clinical and genetic study of sudden cardiac death among children and young adults.
METHODS: We prospectively collected clinical, demographic, and autopsy information on all cases of sudden cardiac death among children and young adults 1 to 35 years of age in Australia and New Zealand from 2010 through 2012. In cases that had no cause identified after a comprehensive autopsy that included toxicologic and histologic studies (unexplained sudden cardiac death), at least 59 cardiac genes were analyzed for a clinically relevant cardiac gene mutation.
RESULTS: A total of 490 cases of sudden cardiac death were identified. The annual incidence was 1.3 cases per 100,000 persons 1 to 35 years of age; 72% of the cases involved boys or young men. Persons 31 to 35 years of age had the highest incidence of sudden cardiac death (3.2 cases per 100,000 persons per year), and persons 16 to 20 years of age had the highest incidence of unexplained sudden cardiac death (0.8 cases per 100,000 persons per year). The most common explained causes of sudden cardiac death were coronary artery disease (24% of cases) and inherited cardiomyopathies (16% of cases). Unexplained sudden cardiac death (40% of cases) was the predominant finding among persons in all age groups, except for those 31 to 35 years of age, for whom coronary artery disease was the most common finding. Younger age and death at night were independently associated with unexplained sudden cardiac death as compared with explained sudden cardiac death. A clinically relevant cardiac gene mutation was identified in 31 of 113 cases (27%) of unexplained sudden cardiac death in which genetic testing was performed. During follow-up, a clinical diagnosis of an inherited cardiovascular disease was identified in 13% of the families in which an unexplained sudden cardiac death occurred.
CONCLUSIONS: The addition of genetic testing to autopsy investigation substantially increased the identification of a possible cause of sudden cardiac death among children and young adults.

Estimates in studies of the incidence of sudden cardiac death vary widely owing to differences in the age range of the various study populations; in addition, studies are often limited by small sample size and by retrospective and non–population-based study designs. A nationwide retrospective study of sudden cardiac death in an unselected population of persons 1 to 35 years of age in Denmark showed an incidence of 2.8 per 100,000 person-years, or 1.9 per 100,000 person-years when only autopsied cases were considered. 8 A similar incidence of 1.8 per 100,000 per year was found after a review of death certificates in England and Wales. 9 In up to one third of cases of sudden cardiac death among children and young adults, a cause of death is not found after a comprehensive autopsy examination that includes toxicologic and histologic studies; these deaths are termed un­ explained sudden cardiac deaths. 3,8,10-12 Unexplained sudden cardiac death is often attributed to cardiac arrhythmia caused by cardiac ionchannel dysfunction, which is undetectable in a conventional autopsy. Noncardiac conditions may also cause sudden death that is clinically indistinguishable from sudden cardiac death. For example, patients with epilepsy have a higher rate of sudden death than persons without epilepsy, and sudden unexpected death in epilepsy is the most common cause of death related to epilepsy. 13 Autopsy-based genetic studies of the major genes for the long-QT syndrome and catecholaminergic polymorphic ventricular tachycardia (a four-gene “molecular autopsy” including the KCNQ1, KCNH2, SCN5A, and RYR2 genes) have identified a pathogenic mutation in up to one third of unexplained sudden cardiac deaths that were referred for postmortem genetic testing. 14,15 However, in population-based, nonreferred cases of unexplained sudden cardiac death, the prevalence of pathogenic mutations in the major genes for the long-QT syndrome is significantly lower. 16,17 Furthermore, population-based studies of human genetic variation have revealed an abundance of rare variants, which has led to increasingly stringent mutation classification criteria and a lower diagnostic yield of autopsy genetic testing for unexplained sudden cardiac death. 18,19 We performed a 3-year, prospective, population-based study of sudden cardiac death among persons 1 to 35 years of age in Australia and New Zealand and focused on determining the underlying cause of death after a comprehensive autopsy examination and genetic testing.

All major forensic pathology centers in Australia and New Zealand prospectively collected premorbid and autopsy investigation data on all cases of sudden cardiac death that occurred in persons 1 to 35 years of age from January 2010 through December 2012. Autopsy examinations were performed by the medical examiners at these centers according to the guidelines of the Royal College of Pathologists of Australasia. 20 In addition, case reports of deaths that had been investigated by a coroner were retrieved from the National Coronial Information System (for Australia) and the Case Management System (for New Zealand) and from the registries of births, deaths, and marriages in each Australian state and territory.
Coroners’ autopsy reports, which included toxicologic and histologic findings, and police reports of death were reviewed to identify cases of sudden cardiac death. Sudden cardiac death was defined as a sudden unexpected death in an otherwise healthy person within 1 hour after the onset of symptoms or, when unwitnessed, within 24 hours after the person was last seen in good health.

DNA was isolated from samples of whole blood obtained at autopsy, as described previously. 18 The genetic analysis of DNA in cases of unexplained sudden cardiac death is summarized in Figure 1. In 51 of the 113 cases of unexplained sudden cardiac death (45%), we performed clinical-grade sequencing (i.e., a next-generation sequencing test accredited through the National Association of Testing Authorities) of the coding exons of 69, 98, or 101 cardiac disease genes on the Illumina MiSeq platform (Victorian Clinical Genetic Services).

From 2010 through 2012, a total of 490 cases of sudden cardiac death were identified in persons 1 to 35 years of age; 360 (73%) were identified at 11 centers in Australia and 130 (27%) at 5 centers in New Zealand. Of the 490 cases of sudden cardiac death, 198 (40%) were unexplained. During the study period, the mean combined population of Australia and New Zealand was 26.74 million persons, of whom 12.59 million were 1 to 35 years of age. 23 On the basis of these figures, the annual incidence of sudden cardiac death in Australia and New Zealand was 1.3 cases per 100,000 persons (95% confidence interval, 1.2 to 1.4); men and boys had a higher incidence than did women and girls (1.8 vs. 0.7 cases per 100,000 persons, P<0.001). Persons 31 to 35 years of age had the highest incidence of sudden cardiac death (3.2 cases per 100,000 persons), and persons 16 to 20 years of age had the highest incidence of unexplained sudden cardiac death (0.8 cases per 100,000 persons) (Fig. 2A).

A definite clinical diagnosis was established in 12 of the 91 families (13%) that underwent follow-up clinical screening; inherited arrhythmogenic diseases were identified in 7 families (the long-QT syndrome in 4, catecholaminergic polymorphic ventricular tachycardia in 1, the short-QT syndrome in 1, and primary conduction disease in 1) and inherited cardiomyopathies were identified in 5 families (arrhythmogenic right ventricular cardiomyopathy in 2 and dilated cardiomyopathy, left ventricular noncompaction, or both in 3)."
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Well, maybe those smart non-mutated kids will figure something out. :D
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This is part of why results in sociology/epidemiology/psychology are so unreliable: not only do they usually not control for genetics at all, they don't even control for the things they think they control for. You have not controlled for SES by throwing in a discretized income variable measured in one year plus a discretized college degree variable. Variables which correlate with or predict some outcome such as poverty, may be doing no more than correcting some measurement error (frequently, due to the heavy genetic loading of most outcomes, correcting the omission of genetic information). This is why within-family designs are desirable even without worries about genetics: they hold constant shared-environment factors so you don't need to measure or model them.
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"Early Visual Concept Learning with Unsupervised Deep Learning", Higgins et al 2016:

"Automated discovery of early visual concepts from raw image data is a major open challenge in AI research. Addressing this problem, we propose an unsupervised approach for learning disentangled representations of the underlying factors of variation. We draw inspiration from neuroscience, and show how this can be achieved in an unsupervised generative model by applying the same learning pressures as have been suggested to act in the ventral visual stream in the brain. By enforcing redundancy reduction, encouraging statistical independence, and exposure to data with transform continuities analogous to those to which human infants are exposed, we obtain a variational autoencoder (VAE) framework capable of learning disentangled factors. Our approach makes few assumptions and works well across a wide variety of datasets. Furthermore, our solution has useful emergent properties, such as zero-shot inference and an intuitive understanding of "objectness"."
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Yeah, read the WP article, Stefan Banach's name popped out. Still ewww.
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The back and forth secret war of the Ohkrana with the myriads of Russian revolutionaries across Europe. When you see how easily and thoroughly the Ohkrana had infiltrated the Russian revolutionaries, you start to see why the Communist leadership would be extraordinarily paranoid about spies. (But also that the revolutionaries were, well before the Revolution, generally highly nasty folks; many of the mentioned revolutionaries would be summarily executed by their comrades.)
The Office of Public Affairs (OPA) is the single point of contact for all inquiries about the Central Intelligence Agency (CIA). We read every letter, fax, or e-mail we receive, and we will convey your comments to CIA officials outside OPA as appropriate. However, with limited staff and ...
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"Is Education Associated With Improvements in General Cognitive Ability, or in Specific Skills?", Ritchie et al 2015:

"Previous research has indicated that education influences cognitive development, but it is unclear what, precisely, is being improved. Here, we tested whether education is associated with cognitive test score improvements via domain-general effects on general cognitive ability (g), or via domain-specific effects on particular cognitive skills. We conducted structural equation modeling on data from a large (n = 1,091), longitudinal sample, with a measure of intelligence at age 11 years and 10 tests covering a diverse range of cognitive abilities taken at age 70. Results indicated that the association of education with improved cognitive test scores is not mediated by g, but consists of direct effects on specific cognitive skills. These results suggest a decoupling of educational gains from increases in general intellectual capacity."
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Abstract: This paper describes InfoGAN, an information-theoretic extension to the Generative Adversarial Network that is able to learn disentangled representations in a completely unsupervised manner. InfoGAN is a generative adversarial network that also maximizes the mutual information between ...
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/not sure if harmful or helpful
The use of tobacco products as dentifrices is still prevalent in various parts of India. Tobacco use in dentifrices is a terrible scourge which motivates continued use despite its harmful effects. Indian legislation prohibits the use of nicotine in dentifrices. ...
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This looks very neat and powerful: "Generalized Network Psychometrics: Combining Network and Latent Variable Models", Epskamp et al 2016:

"We introduce the network model as a formal psychometric model, conceptualizing the covariance between psychometric indicators as resulting from pairwise interactions between observable variables in a network structure. This contrasts with standard psychometric models, in which the covariance between test items arises from the influence of one or more common latent variables. Here, we present two generalizations of the network model that encompass latent variable structures, establishing network modeling as parts of the more general framework of Structural Equation Modeling (SEM). In the first generalization, we model the covariance structure of latent variables as a network. We term this framework Latent Network Modeling (LNM) and show that, with LNM, a unique structure of conditional independence relationships between latent variables can be obtained in an explorative manner. In the second generalization, the residual variance-covariance structure of indicators is modeled as a network. We term this generalization Residual Network Modeling (RNM) and show that, within this framework, identifiable models can be obtained in which local independence is structurally violated. Both generalizations have been implemented in the free-to-use software package lvnet, which contains confirmatory model testing as well as two exploratory search algorithms: stepwise search algorithms for low-dimensional datasets and penalized maximum likelihood estimation for larger datasets. We show in simulation studies that these search algorithms performs adequately in identifying the structure of the relevant residual or latent networks. We further demonstrate the utility of these generalizations in an empirical example on a personality inventory dataset."
Abstract: We introduce the network model as a formal psychometric model, conceptualizing the covariance between psychometric indicators as resulting from pairwise interactions between observable variables in a network structure. This contrasts with standard psychometric models, ...
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Diagram 2.d can be unfolded. None of the un-directed edges introduce a conflict.

https://github.com/ellipt01/cdescent/wiki/6.-Extended-Bayesian-Infomation-Criterion
EBIC has much better specificity for true negatives at small sample sizes in their example model.

Adding the graph to the factor model is a large improvement.
Thanks!
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Challenges in gifted education in elementary or earlier: IQ scores are unstable and so regression to the mean implies that few children in G&T programs will grow up to be gifted. See also "The Junior Meritocracy: Should a child's fate be sealed by an exam he takes at the age of 4? Why kindergarten-admission tests are worthless, at best" http://nymag.com/news/features/63427/index1.html#print

This was connected to reading Genius Revisited, which notes that Hunter Elementary has delivered disappointing results; I consider this as predictable just from the regression to the mean of early childhood scores: http://www.gwern.net/Statistical%20notes#genius-revisited-on-the-value-of-high-iq-elementary-schools
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Offhand, I don't remember which paper it was, but I believe one of them related T with spatial ability, yes. Since spatial ability enters into IQ tests, as long as it doesn't come at the expense of verbal ability (also heavily tested), you would not be surprised if the girls selected for high IQ tend to be somewhat masulinized/under-feminized (either because the greater testosterone boosts spatial means or just increases variability). This offers an interesting contrast to the genetic theory which puts the greater male variance on the extremizing effect of only having 1 X chromosome. It's an interesting theory but I'm not sure it works since the X chromosome isn't that big and won't have that large fraction of intelligent variants.

Yes. See the ending of the writeup. I don't know if parental IQs would improve over an optimal SNP score: even though all one's genes are inherited from parents, parental IQs are themselves measured with error and only imperfectly reflect their own genes... I would have to calculate it out.

Yes, it's quite irritating. The problem is that most can't figure out what the implications of different levels of predictiveness are and what consequences it has for decisions. That's what I liked about the New York article: he at least consulted a statistician/psychologist and got some hard numbers about the regression to the mean, instead of vague rhetoric about 'how can you possibly hope to measure intelligence in just a child'.
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