What is the relationship between parents' income and the eventual earnings of the child? Evidence from a large adoption study: ● Genetically related offspring: The higher parents' income, the higher child income. ● Adopted children: No correlation.
In his 2007 study of Korean American adoptees, Bruce Sacerdote found that the heritability of income was ~32%, and that income transmission was "almost non-existent" for adoptees but was "strongly positive" for non-adoptees
Two studies have examined the effects of nature versus nurture by exploiting quasi-random assignment of Korean-born adoptees to Western families. For most of the outcomes studied, nature was more important than nurture. •