 Deardorff argues that the insights of comparative advantage remain valid if the theory is restated in terms of averages across all commodities.His models provide multiple insights on the correlations between vectors of trade and vectors with relative-autarky-price measures of comparative advantage.What has become to be known as the "Deardorff's general law of comparative advantage" is a model incorporating multiple goods, and which takes into account tariffs, transportation costs, and other obstacles to trade.