Revisiting Moore’s transracial adoption study

Transracial adoption studies are a powerful methodology for examining the relative contribution of genetics and environment to average differences in IQ across racial and ethnic groups. The best — and most famous — transracial adoption study was the Minnesota Transracial Adoption Study (MTAS) conducted by Sandra Scarr and her colleagues (Scarr & Weinberg, 1976; Weinberg

Moderators and Mediators: The Epicycles of the Social Sciences

For over one thousand years, the ptolematic model of the universe dominated Western and Islamic astronomy. All that most people remember about the theory (and often only characteristic they ever learned) is that it placed the earth at the center of the universe, with the planets, sun, and moon all orbiting the earth. This is

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.