The decision to become an entrepreneur is in essence an individual decision. But even when the endowments of inhabitants are taken into account, some regions have persistently higher entrepreneurship rates than others. Proposed explanations for this regional variation are numerous: market...

Cities differ dramatically with respect to the extent in which their economic and other activities are diversified. Some cities are specialized, while other cities harbour a myriad of organizations, performing a huge variety of activities. An unanswered question is: Where does such...