{"kind":"user","text":"Angrist and Evans (1998), 'Children and Their Parents' Labor Supply', Table 7, column (5): in the 1980 Census sample of married women aged 21-35 with two or more children, estimate by two-stage least squares the effect of having more than 2 children on the mother's weeks worked in 1979, using as the instrument the indicator that the first two children are of the same sex. Include as covariates the mother's age and indicators for a first-born boy, a second-born boy, and Black, Hispanic and other race; the paper also includes the age at first birth, which this file does not have. Report the coefficient on having more than 2 children."}