It works in practice, but does it work in (my) theory?

There’s a certain type of person that doesn’t produce any empirical contribution to “Reducing the heredity-environment uncertainty”. Instead, they contribute various theoretical arguments which they take to undermine the empirical data others give. Usually, these people have a background in philosophy or some other theoretical field. A recent example of this pattern is seen on…

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You can’t ignore gene-environment correlations when looking for gene-environment interactions

Humans love interactions, they tell interesting stories (however, no study has investigated this bias, AFAIK). However, statistics and nature hate interactions. Interactions in general have low prior, and because people fail to realize this properly, reports of interactions generally fail to replicate. This is also true for gene-environment interactions (GxE), the love-child of any would…

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The g factor and principal components regression

Jensen spent decades trying to convince people that the g factor (general intelligence) is the primary reason why IQ tests predict stuff, not whatever mental abilities the tests appear to measure or what the makers wanted to measure. E.g. as written in: Jensen, A. R. (2002). “Psychometric g: Definition and substantiation“. In R. J. Sternberg…

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Null hypothesis testing for loadings in unit weighted factor analysis

Just a minor stats point for an otherwise excellent paper. Woodley of Menie, M. A. &  Fernandes, H. B., & Hopkins, W. D. (2015). The more g-loaded, the more heritable, evolvable, and phenotypically variable: Homology with humans in chimpanzee cognitive abilities. Intelligence, 50, 159-163. They use unit weighted factor analysis, which sounds fancy, but it…

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Making better use of the scientific literature: large-scale automatic retrieval of data from published figures

Science is a set of related methods that aim at finding true patterns about the world. These methods are generally designed so as to remove noise from random circumstances (the traditional focus of statistics) and human biases. Current practices are currently not very good at the second part due to the innumerable ways human biases…

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Standard deviation of total SAT scores: not simply the sum of the standard deviations of subtests

Someone on Reddit for SlateStarCodex: AFAIK, SATs are normed to mean of 500 per section and standard deviation of 100. Assuming that math and verbal are highly correlated, that approximates to 1000 mean and 200 standard deviation for the SAT 1600 scale. The median reported score score was 1490, and even the 10th percentile was…

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Regression Modeling Strategies (2nd ed.) – Frank Harrell (review)

www.goodreads.com/book/show/10753824-regression-modeling-strategies I heard some good things about this book, and some of it is good. Surely, the general approach outlined in the introduction is pretty sound. He sets up the following principles: Satisfaction of model assumptions improves precision and increases statistical power. It is more productive to make a model fit step by step (e.g.,…

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The neuroscience of intelligence: very preliminary because of power failure and lack of multivariate studies

I don’t have time to provide extensive citations for this post, so some things are cited from memory. You should be able to locate the relevant literature, but otherwise just ask. Haier, R. J. (2016). The Neuroscience of Intelligence (1 edition). New York, NY: Cambridge University Press. Because I’m writing a neuroscience-related paper or two,…

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Number of siblings vs. total fertility rate

This is commentary on: Ellis, L., Hoskin, A. W., Dutton, E., & Nyborg, H. The Future of Secularism: a Biologically Informed Theory Supplemented with Cross-Cultural Evidence. Evolutionary Psychological Science, 1-19. For over a century, social scientists have predicted declines in religious beliefs and their replacement with more scientific/naturalistic outlooks, a prediction known as the secularization…

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