Essays on international economics: Technology diffusion, knowledge spillovers, and higher education

My doctoral thesis consists of three essays in the field of international economics.;The second essay uses a gravity framework to investigate the effects of distance as well as subnational and national borders in knowledge spillovers. Drawing on the NBER Patent Citations Database, I construct a data set to examine patent citations at the metropolitan level within the U.S. as well as the 38 largest patent-cited countries outside the U.S. Three key findings are documented. First, I find strong subnational localization effects at the Metropolitan Statistical Area (MSA) and state levels: more than 90% of the intranational border effects stem from the metropolitan level rather than the state level. Second, border and distance effects decrease with the age of cited patent, which implies that new knowledge faces larger barriers to diffusion compared to old knowledge. However, over time, the measured effects of border and distance increased. Finally, (assignee) self-citations and aggregation bias are two sources of overestimated aggregate border effects of knowledge spillovers. While self-citations are only 11% of total citations, they account for approximately 50% of MSA and national border effects. Decomposing the data along geographic, age or industrial dimensions contributes to the reduction of border effects.;The third essay documents the major transformation of higher education that has been underway in China since 1999 and evaluates its potential global impacts. Reflecting China's commitment to continued high growth, this transformation focuses on major new resource commitments to tertiary education and significant changes in organizational form. All of these changes have already had large impacts on China's higher educational system and are beginning to be felt by the global educational structure. There are also implications for global trade both directly in ideas, and in idea derived products. This focus on tertiary education differentiates the Chinese case from other countries who instead stressed primary and secondary education at similar stages of development.;Keywords: technology diffusion, diffusion barriers, trade costs, welfare gains, GDP distribution, knowledge trade, knowledge spillovers, gravity, border effect, distance, patent citations, China's higher education.;The first essay assesses the welfare impact of trade and technology diffusion, and investigates the change in the cross-country distribution of GDP due to removal of trade costs and diffusion barriers. The model extends the multi-country Ricardian trade model of Alvarez and Lucas (2007) to include technology diffusion with diffusion barriers. The model is calibrated to match the world GDP distribution, the merchandise trade and technology diffusion shares of GDP, and real GDP per capita for a sample of 31 countries. There are three key findings. First, the welfare gains from removing diffusion barriers are 4-60% across countries, generally larger than the gains from removing trade costs (8-40%). Second, free diffusion reduces the dispersion of real GDP per capita (measured by Gini index) across countries more than free trade does. Third, removing diffusion barriers increases trade, which indicates that diffusion may enhance trade.