To serve foreign markets, firms can either export or set up a local subsidiary through horizontal Foreign Direct Investment (FDI). The conventional proximity-concentration theory suggests that FDI substitutes for trade if distance between countries is large, while exports become more important...

This paper argues that the conventional definition of the elasticity of complementarity is not well suited to deal with the case of increasing returns. It proposes a slightly different formula, that uses a distance function formulation instead of a production function. The proposed definition...