Moreover, we find evidence that suggests that delayed enrollment leads to a larger
reduction in the probability of college graduation for those who score lower on the Armed
Forces Qualifying Test (AFQT). The final section contains a summary and conclusions.
2. Studies of Educational Attainment
Family background variables such as educational attainment and occupations of
parents, family income, and number of siblings are commonly used as control variables in
the study of educational attainment. These family background variables, which appear in
the educational attainment literature, are primarily intended to capture the financial
resources available to students (Light, 1995b). Higher family income is assumed to
increase the likelihood of college enrollment and college graduation, or decrease the
likelihood of college dropout, other things being equal. The number of siblings also affects
educational attainment in the sense that the presence of siblings represents a competing
use of family resources. The educational levels and occupations of parents capture not
only the effect of family resources but also the positive correlations in educational
attainment across generations. These correlations across generations may result from
correlations between educational attainment and family income or from the effect of
educational levels and occupations of parents on youths’ aspirations and the degree of
family support or encouragement to successfully complete college.