The authors estimate the short-run and life-cycle effects of unplanned children on unwed mothers by comparing unmarried women who first gave birth to twins with unwed mothers who bore singletons. They find large short-term effects of unplanned births on labor-force participation, poverty, and...

We study the scale and selectivity of foreign-born PhD students in science and engineering. We focus on students from China, India, Korea, and Taiwan, which together account for most roughly one-third of science and engineering PhD students in the United States. The selectivity of these students...