Browsing by Author "Gao, Han"

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Essays in Labor and Monetary Economics
    (2021-12) Gao, Han
    This dissertation consists of three chapters. Chapter One studies how a potential policy change that raises women’s social security eligibility age from 50 to 60 would affect women’s employment, human capital, and earnings in China. I develop a dynamic model of female labor supply, featuring voluntary retirement; occupational choice; human capital accumulation contingent on occupation, age, and employment status; and child care using time inputs from parents, grandparents, and formal child care from the market. I estimate the model parameters by matching moments on employment, wages, and the time allocation of child care from micro data in China. The policy counterfactual raising women’s social security eligibility age yields two main findings. First, the policy change leads to only a moderate increase in aggregate labor supply because it affects the employment of old and young women in opposite directions. The reduction in social security insurance encourages women above the age of 50 to supply more labor. Yet low-skilled young women with children reduce their labor supply in response to the children’s grandmothers working more and providing less child care. Second, since human capital accumulation is faster on the earlier career path rather than later, the reduction in early career employment leads to persistent losses in human capital and earnings for low-skilled womenChapter Two is a joint work with Mariano Kulish and Juan Pablo Nicolini in monetary economics that revisits the quantity theory of money. In this chapter, we review the relationship between inflation rates, nominal interest rates, and rates of growth of monetary aggregates for a large group of OECD countries. If persistent changes in the monetary policy regime are accounted for, the behavior of these series maintains the close relationship predicted by standard quantity theory models. With an estimated model, we show those relationships to be relatively invariant to alternative frictions that can deliver quite different high-frequency dynamics. We also show that the low-frequency component of the data derived from statistical filters does reasonably well in capturing these regime changes. We conclude that the quantity theory relationships are alive and well, and thus they are useful for policy design aimed at controlling inflation. In Chapter Three, Lichen Zhang and I investigate to what extent changes in the personal income tax schedule have affected the choice to become an entrepreneur in the US. We develop a general equilibrium heterogeneous agent life cycle model with occupation choice and estimate the model using the method of simulated moments (MSM) to match data moments from from the Panel Study of Income Dynamics (PSID) and the Panel Studies of Entrepreneurial Dynamics (PSED). We simulate the path of population share of entrepreneurs over time by introducing to the model a sequence of tax schedule changes as in the real world and validate the model by showing that it replicates the differential impacts of tax schedules changes on individuals at different ages. Our simulation shows that income tax schedule changes alone explains most of the increase in entrepreneurship in the periods. We also highlight the importance of entrepreneurs and entrepreneurial choice elasticities by age in the design of optimal tax in a realistic quantitative life cycle model.
  • Thumbnail Image
    Item
    Keeping the Heat off of the Street: Trends in Radiological Material Security Legislation
    (2023) Benda, Samuel; Boualaphanh, Skylor; Gao, Han
    The Stimson Center is developing the Radiological Source Security Legal Index and Online Tool (RadSecLexis), an online database aiming to measure countries' efforts to implement IAEA guidance and publicly make measurements, laws, and regulations available to those seeking examples of national implementing measures. This research project aims to assist the Partnerships in Proliferation Prevention Program in gathering quantitative data on United Nations member state legislation promulgated from December 2018 to September 2021 concerning the physical protection of radioactive and nuclear materials. This study examines the relationship between international radiological and nuclear security events and the implementation of national radiological security measures, exploring whether there is a correlation or causation between these events and subsequent policy changes. In our findings, we can identify trends in regional cooperation and similar attitudes toward implementing international guidelines. However, it is still being determined if there is a correlation or causation between international incidents and the passing of national security measures due to gaps in data and analytics we could not access. In addition, there are disparities in implementing these measures. Regional challenges involve international cooperation in nuclear and radiological security due to a need for more resources or access to technology and funding. The paper will review the foundation of our methodology, which elaborates on the experimentation of different data collection methods, including utilizing Google Search and Artificial Intelligence. A streamlined process was developed for the collection, cleaning, cross-referencing, and organization of data most efficiently due to the time constraints of this project. However, our data collection operations needed to be improved with the accuracy of the gathered information. Using the Multiple Case Sampling Method, we gathered multiple sources of information. We developed databases from the IAEA's June 2022 Conference on Safety and Security of Radiological Sources, the Incident Trafficking Database, and the James Martin Center for Nuclear Studies reports drawing connections to global trends in national laws and regulations related to radioactive materials. Our qualitative and quantitative section overviews identified global trends such as the collective concerns on the security of radioactive and nuclear materials in Ukraine and challenges with implementing IAEA guidelines in select nations from the Global South.