In this dissertation, the first two chapters on mortgage markets show that statistical discrimination and market power derived by lenders from mortgage search costs of borrowers in the US have a large welfare cost for a borrower and are important sources of refinancing inaction. The third chapter shows that a winner-take-all electoral system is better than a proportional system for economic growth-enhancing public investment since it reduces the likelihood and size of coalition governments. Chapter 1 investigates how statistical discrimination by lenders, a tool that separates borrowers who differ in search intensity, affects welfare and monetary policy transmission to consumption. A general equilibrium model with two types of borrowers who...