We develop a monopolistic-competition model of closed two-sector one-factor economy, where agents are (continuously) heterogeneous in their entrepreneurship abilities and choose between being employees or entrepreneurs. The sufficient conditions in terms of variable elasticity of substitution...

Natural advantages determine where agglomerations emerge. Also, efficiency and economies of scale determine how many agglomerations subsist and how they interact, forming complex urban hierarquies. Moreover, physical characteristics influence the way humans divide land into irregular parcels we...