Before revision:  We provide an explanation to the fact that the extensive margin of trade account for a large fraction of the greater exports of large economies, as well as for a number of stylized facts described by the literature on trade networks such as the power-law distribution of connectivity and the fat tails displayed by the distribution of  the growth rates of trade flows.
After revision:  We provide an explanation to the fact that the extensive margin of trade account for a large fraction of the greater exports of large economies, as well as for a number of stylized facts described by the literature on trade networks such as the power-law distribution of connectivity and the fat tails displayed by the distribution of link values, the growth rates of trade flows.