Black-White gap – Clear Language, Clear Mind

New paper out: Filling in the Gaps: The Association between Intelligence and Both Color and Parent-Reported Ancestry in the National Longitudinal Survey of Youth 1997

May 25, 2019 0 Comments

We’ve got a new important paper out in the special issue on race and intelligence in Psych: Hu et al, 2019, Filling in the Gaps: The Association between Intelligence and Both Color and Parent-Reported Ancestry in the National Longitudinal Survey of Youth 1997, Psych Little research has dealt with intragroup ancestry-related differences in intelligence in…

intelligence / IQ / cognitive ability

The mysterious PC1 ancestry component

October 25, 2018 0 Comments

Mehta, C. M., Malins, J. G., Noble, K. G., & Gruen, J. R. (2017). Cortical area and subcortical volume mediate the effect of parental education and adverse experiences on cognitive performance in youth. bioRxiv, 160424. Remember “poverty shrinks the brain from birth”? From birth! Fast acting that poverty, actually before birth too. Anyway, Kimberly Noble…

Genomics, intelligence / IQ / cognitive ability

How long do we need affirmative action?

October 25, 2018 0 Comments

1976, Constance Baker Motley, African American judge: Judicial predictions of reduction or elimination of the RAG through color – based decisions approached the l udicrous. In rendering the decisive vote on the High Court decision Grutter vs. Bolling (539 U.S. 2003) and endorsing a continuing legality of quotas, Justice Sandra Day O ’ Connor averred,…

History, intelligence / IQ / cognitive ability

The original texts of the Eyferth study

June 25, 2018 0 Comments

Often discussed, occasionally cited, but rarely read — certainly a highly suspicious combo — I post here the original German language final version (we think): Eyferth, K. (1961). Leistungen verschiedener Gruppen von Besatzungskindern in Hamburg-Wechsler Intelligenztest für Kinder (HAWIK). Archiv für die gesamte Psychologie, 113, 224-241. Eyferth, K. (1959). Eine Untersuchung der Neger-Mischlingskinder in Westdeutschland….

intelligence / IQ / cognitive ability

Comments on Fagan and Holland (2007)’s racial equality paper

March 3, 2018 0 Comments

Someone sent me some questions on this study: Fagan, J. F., & Holland, C. R. (2007). Racial equality in intelligence: Predictions from a theory of intelligence as processing. Intelligence, 35(4), 319-334. African-Americans and Whites were asked to solve problems typical of those administered on standard tests of intelligence. Half of the problems were solvable on…

intelligence / IQ / cognitive ability

The US Black-White cognitive ability gap in 1850, 1870 and 1900 censuses

August 31, 2017 0 Comments

Using the crude measures of literacy and numeracy discussed in a previous post, it is possible to quantify the cognitive ability gap for US Black-White in the 1800s. The data come from: A’Hearn, B., Baten, J., & Crayen, D. (2009). Quantifying quantitative literacy: Age heaping and the history of human capital. The Journal of Economic…

Differential psychology/psychometrics

How to do a meta-analysis of Black-White IQ gap

March 4, 2017

twitter.com/HoustonEuler/status/837894199814955008 There’s been some talk about whether the SIRE (self-identified race/ethnicity) gaps are closing and if so how much and when they did that. The matter is complicated for many reasons. The last major, published review is very dated, as it is from 2001. Roth, P. L., Bevier, C. A., Bobko, P., Switzer, F. S.,…

Differential psychology/psychometrics, intelligence / IQ / cognitive ability