Can Hepatitis B Mothers Account for the Number of Missing Women? Evidence from Three Million Newborn
2007/04/24
研討會日期 : 2007-04-24
時間 : 15:00
主講人 : Prof. Ming-Jen Lin
地點 : B棟110室
演講者簡介 : Prof. Ming-Jen Lin為芝加哥大學經濟學博士(2002)。
現為台灣大學經濟系助理教授。
其主要研究領域為Law and Economics、Labor Economics、Demography and Health。
演講摘要 : The high sex ratio in many Asian countries has previously been regarded as the ‘missing women’ phenomenon, with misogyny as its prime cause. However, a series of studies has emerged in which it is argued that since the sex ratio of the offspring of Hepatitis B mothers is around 1.5, as much as half of the missing women (75% in China) can be explained by this natural disease. Using novel data from the National Hepatitis B Immunization Program in Taiwan, this study attempts to contribute to this issue by investigating three million births in Taiwan and the HBsAg status of the mothers at the time of the pregnancy. We demonstrate that the marginal probability of an HBsAg(+) mother having a male birth is only 0.0025. We also find that the greatest effect on male births appears among higher order births, and this number remains robust across all birth orders and model specifications. We also show that the bias caused by availability of sex selection technology during our data period is minimal, since the sex ratio among firstborn children to HBV mothers is still very low. Given that 15 percent of all mothers are infected with HBV, the disease can only raise the sex ratio from a baseline of 105 to 105.165. Our estimates suggest that the effect of HBV mothers on sex ratio among their offspring is minimal, and hence can account for only a small portion of the case of missing women.
