Verbal tilt model confirmed for political behavior
This paper came out a while ago, but I neglected to comment on it. You may recall 5 years ago I forwarded the verbal tilt model of certain behavioral patterns…
The issue with early interventions for cognitive traits
There are numerous intervention studies aim at improving cognitive traits. While one can aggregate these in ways that give the appearance of impact, when looked at properly they don't really…
Two new review articles on national IQs
Heiner Rindermann sent me his new review paper: Rindermann, H. (2025). Low cognitive ability estimates in developing countries: A statistical analysis of their credibility. Human Evolution, 40(3–4), 257–284. https://doi.org/10.14673/HE2025341159, Developing countries…
What explains the Big Pisa Decline of 2022? It’s not COVID
You may have seen posts like this: Two explanations are commonly offered: Phones/computers got suddenly more addictive than before (Tiktok-era) COVID was bad for learning. Let's start with the second.…
New causal variant estimates for intelligence
There's a new genetic analysis of intelligence out: Chen, H., Liao, Y., Tang, L., Wei, X., Li, T., & Chen, W. (2025). Multivariate genome-wide analysis reveals shared genetic architecture and…
Population size is not important for country outcomes
There is a recurrent feature of the immigration debate that goes like this: Emil: Look at how negative the fiscal contributions of 3rd world migrants are. People: Heh, that's nice,…
Migrant selection and informative priors
Chris Rufo wasn't happy with the recent American experience with the Somalians scamming the welfare state and wrote about how one should take into account "which national populations" people wish…
Classification error and relative rates
Our latest big project on mugshots and race misclassification by the US law enforcement. It is currently going viral on X: You can start by reading the thread summary, or…
Against the economists on school spending
Some days ago I posted a chart about school spending (per-pupil spending) and math test scores: Note how I didn't say this cross-sectional scatterplot proves anything about causality, but we…
Are IQ scales interval or ordinal?
One of the more obscure objections to intelligence testing is that really the tests are only on ordinal scale, and thus many of the usual statistical operations are undefined. Recall,…