This article deals with econometric developments for the estimation of gravity model, which allow to get convergent parameter estimates even when a correlation exists between the explanatory variables and the specific unobservable characteristics of each individual. We implement panel data...

The "distance effect" measuring the elasticity of trade flows to distance has been rising since the early 1970s in a host of studies based on the gravity model, leading observers to call it the "distance puzzle". This paper reviews the evidence and explanations. Using an extensive data set of...