This paper determines which gravity models are the best adapted to the study of the trade evolution of several economic areas and the behaviors heterogeneity of the countries that belong to these areas (fixed effect model; random effect model). Applied to the countries of UE15, NAFTA, MERCOSUR,...

This paper determines which are, among different type of gravity model, those best adapted to the study of the evolution of trade of several economic areas and of the heterogeneity of the behaviors of the countries constitutive of these zones (fixed effect model; random effect model; model with...