This paper examines data on trade flows between West German Bundeslander (federal states) and East Germany to explore the effect of national borders on trade. Although the data covers only a small fraction of intra-German trade flows, I find a home bias of about factor 2.2; West German shipments...

By exploiting a commuting policy that led to a sharp and unexpected inflow of Czech workers to areas along the German-Czech border, we examine the impact of an exogenous immigration-induced labor supply shock on local wages and employment of natives. On average, the supply shock leads to a...