Third, our binary indicator of educational attainment (college degree) misses the wide range of educational credentials and years of completed schooling. This is particularly important because the social push model, for which we did not find clear evidence in the GWGEI models, typically focuses on the “average environment” (Shanahan and Boardman 2009) and hypothesizes that genetic factors are least important at the highest and lowest levels (for education, people with postdoctoral work and high school dropouts) but increase in salience at the average level (high school education and some college).
