NBER Publications by Nancy Qian

We exploit regional variation in suitability for cultivating potatoes, together with time variation arising from their introduction to the Old World from the Americas, to estimate the impact of potatoes on Old World population and urbanization. Our results show that the introduction of the potato was responsible for a significant portion of the increase in population and urbanization observed during the 18th and 19th centuries.

Many believe that increasing the quantity of children will lead to a decrease in their quality. This paper exploits plausibly exogenous changes in family size caused by relaxations in China's One Child Policy to estimate the causal effect of family size on school enrollment of the first child. The results show that for one-child families, an additional child significantly increased school enrollment of first-born children by approximately 16 percentage-points. The effect is larger for households where the children are of the same sex.

This paper estimates the long run impact of famine on survivors in the context of China's Great Famine. To address problems of measurement error of famine exposure and potential endogeneity of famine intensity, we exploit a novel source of variation in regional intensity of famine derived from the unique institutional determinants of the Great Famine. To address attenuation bias caused by selection for survival, we estimate the impact on the upper quantiles of the distribution of outcomes. Our results indicate that in-utero and early childhood exposure to famine had large negative effects on adult height, weight, weight-for-height, educational attainment and labor supply.

Many countries with "deficits" in their female population see banning sex-selective abortion as a way to curb the observed sex imbalance. However, they rarely discuss the potentially negative unintended consequences of this ban on female survival rates as parents may be forced to substitute post-natal for pre-natal sex-selection. This paper presents novel empirical evidence on the impact of access to abortion on sex ratios at birth and relative female infant mortality. We use the universe of birth and death registry data from Taiwan and exploit plausibly exogenous variation in the availability of sex-selective abortion caused legislative changes to identify the causal effects of sex-selective abortion on sex ratios at birth and excess female mortality. We find that sex-selective abortion i...