Essays on the economics of e-commerce, integration and infrastructure

This dissertation consists of three essays. The first essay considers the effects of the emergence of the E-market upon the economy. The other two essays study the effects of public infrastructure when two countries are integrated. One pertains to the role of public infrastructure in determining locations of firms. The other concerns the relation of public infrastructure and migration.; Chapter 2 analyzes the implication of the emergence of the E-market by focusing on a different characteristic of the E-market from traditional markets that consumers and sellers are able to trade with one another through the E-market, although they are apart physically. This characteristic of the E-market enables sellers to draw enough on large scale economies in order to offer a new product to the economy. The E-market also brings a welfare gain for the economy by providing a larger number of varieties of products.; Chapter 3 analyzes the role of public infrastructure in determining location of firms. This chapter assumes that productivities of factors in a country depend on public infrastructure in the country. Under this assumption, better infrastructure provides lower marginal production costs to firms. Thus, firms tend to move to the country that has the better infrastructure. When two countries are integrated and firms are free to move between the two countries, countries compete in inducing to firms by increasing investment in infrastructure. Thus countries tend to over-invest in infrastructure compared to the optimal investment for the integrated economy.; Chapter 4 studies a relationship between public infrastructure and migration when two countries are unified. It is shown that people tend to migrate to the infrastructure-rich country. Chapter 4 develops a fully closed computable general equilibrium model by using a logit model. Using this model, two possible immigration policies are investigated: free immigration and no migration from the infrastructure-poor country to the infrastructure-rich country. This chapter also develops an alternative unification policy that combines an immigration control and income subsidy. This alternative unification policy is shown to make both countries better off compared to the free immigration policy without compensation.