Since the pioneering work of Krugman (1980) economists try to quantify the welfare gains from an increase in traded variety. The seminal work of Feenstra (1994) and its application to the U.S. of Broda and Weinstein (2006) allowed this quantification for the first time using highly disaggregated...

The main conclusions of the thesis are that pension reform can be welfare improving if losses and benefits are redistributed by the central government. The possibility of welfare improving social security reform comes from a more efficient use of an immobile production factor, such as land....