Stupid? No. Unfamiliar? Yes. The meaning of low mean IQs in developing nations

Illiterate people’s thinking probably remains grounded in their everyday experience. When these people take a test that solely measures abstract thinking, they perform poorly. This does not make them stupid. Instead, it shows the disconnect between their natural mode of thought and the unfamiliar test content.

Notes on videos of Arthur Jensen defending his work

The most important name in intelligence research in the second half of the 20th century is educational psychologist Arthur Jensen (1923-2012). From the late 1960s until his death, Jensen was the world’s foremost intelligence researcher who singlehandedly made methodological and scientific breakthroughs that greatly advanced intelligence research. I never got to meet Arthur Jensen, but

The lost intelligence tests

Last year, I co-authored an article with my student where we identified the first known publication of the subtests that appear on the Stanford-Binet 5, the WPPSI-IV, WISC-V, and WAIS-IV (Gibbons & Warne, 2019). Much to our suprise, we found that the majority of subtest formats on these popular intelligence tests were created by 1908.

Terman’s non-geniuses: Shockley and Alvarez

Over the years, I’ve become a scholar of Lewis Terman’s Genetic Studies of Genius, which was a study that followed the lives of 1,528 high-IQ children from 1921 to 1999. It’s a landmark study in the history of psychology and was groundbreaking in the fields of methodology, gifted education, intelligence research, and developmental psychology (Warne,

Comparing the 1975 and 1996 APA statements on intelligence

One of the most highly cited articles in intelligence research is a 1996 report commissioned by the American Psychological Association’s Board of Scientific Affairs to provide an authoritative statement on the science of intelligence (Neisser et al., 1996). What many people do not know, though, is that this was not the first time APA’s Board

Thoughts on low national IQs, intellectual disability, and data quality

[February 2023 update: I recently published an article analyzing national IQs. The article incorporates some of the ideas in this blog post.] A recent now-retracted paper in Psychological Science by Clark et al. (2020) caused some controversy lately in the psychological community. The authors found some correlations with other national-level data that could be theoretically