Sampling top psychology journals in the mid-2000s, psychologist Jeffrey Arnett observed that 96 percent of research subjects came from Western, industrialized countries that represented just 12 percent of the world’s population, and that about two-thirds were from the U.S. Subjects seemed to largely be sourced from the countries in which the researchers lived. In 2010, citing this finding and others, Joseph Henrich, Steven Heine, and Ara Norenzayan introduced the term WEIRD to describe this subpopulation. They expanded on the problems with focusing so exclusively on such participants and with assuming that findings from a relatively unrepresentative group generalized to the rest of the world.