Sex preferences, sex selection, and women's labor supply

This dissertation consists of two essays. In the first essay, I investigate the causes for high sex ratios in China and India that have historically concerned researchers (Sen 1990). I identify sex selection via infanticide and abortion as the principal explanation for the sex ratio distortion, and rule out competing explanations such as biology (Oster 2005) or differential mortality rates. Consistent with recent work (Jha et al. 2006), I find that the sex ratio of first-order births is close to the natural rate and steeply rising following the birth of low-order daughters, indicating that mothers are practicing pre-natal sex selection or immediate infanticide. Sex ratios are found to be higher among those anticipating lower fertility, such as those under stricter government fertility limits.;I present a model of a mother's fertility choice when she has access to a sex-selection technology and faces a mandated fertility limit. By exploiting variation in fines levied in China for unsanctioned births, I demonstrate that higher fine regimes discourage fertility but are associated with higher sex ratios among those who choose to have an additional child. I then estimate a structural model of parental preferences using China's 2000 census data that indicates that a son is worth 2.90 years of income more than a daughter, and the premium is highest among less educated mothers and rural families. I conclude with a set of simulations to model the effect on sex ratios and total fertility of a proposed subsidy to families who fail to have a son, and find that such a policy would reduce sex ratios and lower overall fertility.;The second essay attempts to identify the causal link between fertility and the labor supply of married women. Economic models of home production predict a tradeoff between family size and child outcomes, as well as a tradeoff between a mother's fertility and her labor supply. Recent empirical work suggests that while family size and these outcomes are correlated, the causal impact is negligible when estimated through Instrumental Variables (sex preference, twinning). I find that in Taiwan, intense son preference produces 2SLS estimates of a mother's labor response that are larger than OLS estimates, suggesting that previous IV analyses may rely on instruments too weak for consistent estimation. My estimates indicate that for mothers in Taiwan, a child induced by sex preferences imposes a cost of roughly one year of foregone labor supply, with estimates slightly larger for better educated mothers. The analysis also identifies fertility timing as a key predictor of female labor supply, indicating that IV estimates using twin-births may understate the impact of an additional pregnancy and birth on a mother's labor force experience.;I present a model of a mother's joint determination of fertility and labor supply that suggests the estimated Local Average Treatment Effect will rise in proportion to the intensity of sex preferences. Consistent with the model's predictions, I find that in Taiwan, the extra birth induced by sex preferences causes a shift in the family's consumption mix towards inferior goods and away from normal goods, but no such effect is found among American families. My results indicate that IV estimates using twinning or weak sex preferences may understate the true cost of childbearing on family outcomes.