The simple gravity equation explains a great deal about the data on bilateral trade flows and is consistent with several theoretical models of trade. We argue that alternative theories nevertheless predict subtle differences in key parameter values, depending on whether goods are homogeneous or...

We develop a procedure to rank-order countries and commodities using dis-aggregated American imports data. We find strong evidence that both countries and commodities can be ranked, consistent with the "produce cycle" hypothesis. Countries habitually begin to export goods to the United States...

We develop a procedure to rank-order objects using censored panel data sets. We illustrate this by ranking countries and commodities using disaggregated American import data and find evidence that countries and commodities can be ranked. Countries habitually begin to export goods to the United...