Differential psychology/psychometrics

Autistic children attend a course delivered by a specialised teacher Caroline Berge (L) at the College du Parc in Aulnay-sous-Bois, northeast of Paris on October 9, 2019. (Photo by Christophe ARCHAMBAULT / AFP) (Photo by CHRISTOPHE ARCHAMBAULT/AFP via Getty Images)

Autism diagnoses are rising, yes, but autism, probably not

Post author:Emil O. W. Kirkegaard
Post published:9. January 2024
Post category:Differential psychology/psychometrics Psychiatry

We can read in many outlets that the reason autism is increasing in prevalence is that clinicians are becoming more aware of it. The idea being that autism was already…

New study: Intelligence and Group Differences in Preference for Breasts over Buttocks

Post author:Emil O. W. Kirkegaard
Post published:7. January 2024
Post category:Evolutionary Psychology intelligence / IQ / cognitive ability Sociology

George Francis and I have a new exciting study out, the formal and finalized version of George Francis' 2022 blogpost: Francis, G., & Kirkegaard, E. O. W. (2023). Intelligence and…

New study out: Systemic Racism Does Not Explain Variation in Race Gaps on Cognitive Tests

Post author:Emil O. W. Kirkegaard
Post published:6. January 2024
Post category:intelligence / IQ / cognitive ability Sociology

The new issue of Mankind Quarterly just came out. It appears I have no less than 6 pieces in this, so let's get started. Kirkegaard, E. O. W. (2023). Systemic…

Money and crime: the relationship that wasn’t

Post author:Emil O. W. Kirkegaard
Post published:22. December 2023
Post category:Criminology Differential psychology/psychometrics Economics

There must be 10,000s of studies and news articles reporting findings that wealth or income is negatively related to crime. In other words, poverty causes crime. The popular theory being…

Measurement error and group differences explained

Post author:Emil O. W. Kirkegaard
Post published:13. December 2023
Post category:intelligence / IQ / cognitive ability Math/Statistics

I have often talked about how measurement error impacts correlations between two variables. Here we are talking about classical measurement error, which is theoretically understood as adding a normally distributed…

Heritability, within and between groups

Post author:Emil O. W. Kirkegaard
Post published:12. November 2023
Post category:Genetics / behavioral genetics intelligence / IQ / cognitive ability

There is a new preprint that's making the rounds on Twitter: Schraiber, J. G., & Edge, M. D. (2023). Heritability within groups is uninformative about differences among groups: cases from…

What if somewhere, someone used to look at their polygenic scores?

Post author:Emil O. W. Kirkegaard
Post published:10. November 2023
Post category:Genetics / behavioral genetics intelligence / IQ / cognitive ability

Undark magazine has a new piece out where a journalist expresses concern about people looking at their own DNA results: From a Fledgling Genetic Science, A Murky Market for Prediction.…

National “learning-adjusted years of schooling”

Post author:Emil O. W. Kirkegaard
Post published:31. October 2023
Post category:intelligence / IQ / cognitive ability

We've recently seen national "basic skills" and Team Economist is now back with another one: National "learning-adjusted years of schooling". We might say that national intelligence enjoys a paradoxical popularity.…

Sasha Gusev won’t answer basic questions about his beliefs

Post author:Emil O. W. Kirkegaard
Post published:21. October 2023
Post category:Genetics / behavioral genetics intelligence / IQ / cognitive ability

Sasha Gusev is a statistical geneticist who spends a lot of time on Twitter. He has been attacking various behavioral genetics studies lately, thus earning some ire from people in…

Palestinians in your country: what to expect?

Post author:Emil O. W. Kirkegaard
Post published:13. October 2023
Post category:Immigration intelligence / IQ / cognitive ability

With a war looming and probably lots of Palestinian refugee applications on the horizon, I thought it would be wise to summarize what we have so far about them. The…