The S factor in Brazilian states
Abstract Sizeable S factors were found across 3 different datasets (from years 1991, 2000 and 2010), which explained 56 to 71% of the variance. Correlations of extracted S factors with…
Harvard SAT and IQ: How much regression towards the mean?
http://pumpkinperson.com/2015/04/13/is-the-sat-an-iq-test/ Blog commenter Lion of the Judah-sphere has claimed that the SAT does not correlate as well with comprehensive IQ tests as said IQ tests correlate with one another. At…
The general brain factor, working memory, parental income and education, and racial admixture
UNFINISHED ANALYSIS. POSTED HERE TO ESTABLISH PRIORITY. MORE TO FOLLOW! Updated 2015-12-04 Remains to be done: Admixture analysis (doing) Proofreading and editing Deciding how to control for age and scanner…
Transracial adoption study: Bruce et al (2009)
Introduction This is a post in the on-going series of comments on studies of international/transracial adoption. A global genetic/hereditarian model of cognitive differences and their socioeconomic effects implies that adoptees…
The S factor in the British Isles: A reanalysis of Lynn (1979)
Read the study PDF. Emil O. W. Kirkegaard, Ulster Institute for Social Research. Email: emil@emilkirkegaard.dk Abstract I reanalyze data reported by Richard Lynn in a 1979 paper concerning IQ and socioeconomic…
Transracial adoption study: Stams et al, 2000
This is another relatively small international adoption study. 159 children were adopted in homes in the Netherlands from Sri Lanka, Korea and Colombia. Participants are described as: The present study…
Transracial adoption study: Lindblad et al, 2003
As Jason Malloy has mentioned, it is strange that in the race intelligence debates, people usually cite the same few studies over and over: Shortly after writing that post, I…
Spearman’s hypothesis on item-level data from Raven’s Standard Progressive Matrices: A replication and extension
Emil O. W. Kirkegaard1 Abstract Item-level data from Raven’s Standard Progressive Matrices was compiled for 12 diverse groups from previously published studies. Jensen’s method (method of correlated vectors) was used…
International differences in intelligence can be confusing: A commentary on Harrison et al (2015)
Abstract In this commentary I explain how mean differences between normal distributions give rise to different percentages of the populations being above or below a given threshold, depending on where…
Opinions about nuclear energy and global warming, and wordsum intelligence
Abstract Using data from the ANES 2012 survey, I investigate the relationship between wordsum IQ estimates (unweighted sums, factor analytic and item-response theory scores) and opinions about nuclear energy and…