황지수 교수

Sex ratio at birth remains highly skewed in Asian countries due to son preference. In South Korea, however, it has declined to the natural ratio. In this paper, we investigate whether son preference has disappeared in Korea by analyzing parents' time and monetary inputs by the sex of their child. We exploit randomness of the first child's sex to overcome potential bias from endogenous fertility decisions. Our findings show that mothers are more likely to work after having a girl, girls spend twi

Sex ratio at birth remains highly skewed in many Asian countries because of son preference. The ratio in South Korea, however, declined beginning in 1990 and reached the natural range in 2007. We study changes in child gender effects on fertility and parental investment during this period of decreasing sex ratio at birth. We find that gender discrimination on the extensive margin (fertility), such as sex-selective abortions and son-biased stopping rules, have nearly disappeared among recent coho

South Korea and other developed regions in East Asia have become forerunners of prolonged lowest-low fertility. South Korea's total fertility rate has been below 1.3 for two decades, the longest duration among OECD countries. Using vital statistics and census data, I study recent trends in the country's cohort fertility covering women born before the 1960s to those born in the 1980s. Analyzing outcomes at both the intensive margin of fertility (i.e., timing and number of children) and the extens

Many data breaches happened due to poor implementation or complete absence of security controls in private companies as well as in government organizations. Many countries work on improvement of security requirements and implementing them in their legislation. However, most of the security frameworks are reactive and do not address relevant threats. The existing research suggests Digital Forensic Readiness as proactive measures, but there is only one example of its implementation as a policy. Ou

본 연구는 1999~2019년 생활시간조사 자료를 이용하여 지난 20년에 걸친 부 모의 자녀 돌봄 시간 변화를 분석한다. 특히 부모 학력에 따른 차이를 살펴봄으 로써 자녀에 대한 시간 투자가 더욱 불평등해지고 있는지 알아본다. 회귀분석 결 과 여성, 남성 모두 자녀 돌봄 시간이 증가하였으며, 고학력과 저학력 간 돌봄 시간의 격차 또한 유의하게 확대된 것으로 나타났다. 구체적으로 여성의 경우 경 제활동이나 어린 자녀 유무와 상관없이 고학력 母가 저학력 母에 비해 자녀와 함께 하는 시간이 많았으며, 남성은 어린 자녀가 있는 경우 그리고 주말에 고학 력 父가 저학력 父에 비해 육아 시간을 늘린 것으로 나타났다. 본 결과는 부모의 시간 투자 차이를 통해서도 세대 간 이동성이 약화될 수 있음을 시사한다.

longevity gains. Old agents become poorer from unexpected longevity gains than from expected gains, as they cannot prepare (save) for the former in advance. In an overlapping-generations model with means-tested pay-as-you-go social security, we show that young agents reduce their fertility when longevity increases because they need to save more for their old age ("life-cycle effect"), and in the unexpected case, they also need to pay taxes to support the impoverished elderly ("policy effect"). U

Widespread agreement that a political reform is necessary is no guarantee that it is actually undertaken in a timely manner. There is often a delay before action is taken and reform packages that would be most efficient to implement all at once are often done only gradually. We propose a theoretical model explaining this behavior and show that when voters have present‐biased, time‐inconsistent preferences, gradualism can arise in equilibrium and be welfare‐enhancing. This is because without the

We utilize the phased rollout of COVID-19 vaccines by exact birth date in South Korea as a natural experiment for testing risk compensation. People may resume face-to-face social activities following vaccination because they perceive lower risk of infection. Applying a regression discontinuity design based on birth date cutoffs for vaccine eligibility, we find no evidence of risk-compensating behaviors, as measured by large, high-frequency data from credit card and airline companies as well as s