The effect of education on spousal education:a genetic approach

We investigate the causal effect of education on spousal education using a sample of couples from the Health and Retirement Study. We estimate reduced-form linear matching functions derived from a parsimonious matching model which links spouses’ education. Using OLS we find that an additional year in husband's (resp. wife's) education is associated with an average increase in wife's (resp. husband's) education of 0.41 years —95% CI: 0.37, 0.45 (resp. 0.63 years —95% CI: 0.57, 0.68). To deal with endogeneity issues due to measurement error and omitted variables, we use a measure of genetic propensity (polygenic score) for educational attainment as an instrumental variable. Assuming that our instrument is valid, our 2SLS estimate suggests that an additional year in husband's (resp. wife's) education increases wife's (resp. husband's) education by about 0.49 years —95% CI: 0.35, 0.62 (resp. 0.76 —95% CI: 0.56, 0.96). Since greater genetic propensity for educational attainment has been linked to a range of personality and cognitive skills, we allow for the possibility that the exclusion restriction is violated using the plausible exogenous approach by Conley et al. (2012). A positive causal effect of education on spousal education cannot be ruled out, as long as one standard deviation increase in husband's (wife's) genetic propensity for education directly increases wife's (husband's) education by less than 0.2 (0.3) years.