In 19 (sub)samples from seven countries (United States, Austria, Germany, Costa Rica, Ecuador, Vietnam, Brazil), we analyzed the impact of parental education compared with wealth on the cognitive ability of children (aged 4–22 years, total N = 15,297). The background of their families ranged from poor indigenous remote villagers to academic families in developed countries, including parents of the gifted. Children’s cognitive ability was measured with mental speed tests, Culture Fair Intelligence Test (CFT), the Raven’s, Wiener Entwicklungstest (WET), Cognitive Abilities Test (CogAT), Piagetian tasks, Armed Forces Qualification Test (AFQT), Progress in International Reading Literacy Study (PIRLS), Trends in International Mathematics and Science Study (TIMSS), and Programme for International Student Assessment (PISA). Parental wealth was estimated by asking for income, indirectly by self-assessment of relative wealth, and by evaluating assets. The mean direct effect of parental education was greater than wealth. In path analyses, parental education ( βEd) also showed a stronger impact on children’s intelligence than familial economic status ( βIn, total effect averages: βEd= .30–.45, βIn= .09–.12; N = 15,125, k = 18). The effects on mental speed were smaller than for crystallized intelligence, but still larger for parental education than familial economic status ( βEd→MS= .25, βIn→MS= .00, βEd→CI= .36, βIn→CI= .09; N = 394, k = 3). Additional factors affecting children’s cognitive ability are number of books, marital status, educational behavior of parents, and behavior of children. If added, a general background (ethnicity, migration) factor shows strong effects ( βBg= .30–.36). These findings are discussed in terms of environmental versus hidden genetic effects.
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