We use a dynamic trade model with two sectors and two types of workers to analyze the optimal setting of income-generating tariffs. This approach allows us to take account of adjustment dynamics, distributional aspects and the time horizon of policy makers and workers. In response to a...

Many studies use tariffs to measure changes in trade policy. This paper shows that standard sources for tariffs suffer from substantial measurement error due to misreporting and the resulting false imputation: Countries fail to report tariffs every year and missing data are more prevalent for...

This paper reveals significant errors in a key variable in international trade: tariff rates. The issues arise from incomplete reporting, leading to measurement error from false interpolation by the data provider, the World Integrated Trade Solution (WITS), and selection bias from dropping...

This paper reviews the optimal tariff theory of Kahn (1947) and Graaff (1949), and finds that their solutions are not optimal. Indeed, their policy recommendations are welfare detrimental. Graaff's tariff is even uncertain, can be positive or negative

This paper unveils three dirty tricks exercised by Kemp and Shimomura (2000): 1. They play around with an ambiguous trade balance equation; 2. They change the convex social indifference curve into a concave one; 3. They think they can dictate market prices. Without these tricks, there is no...

This paper points out some mistakes in the so-called optimal tariff theory. When they are corrected, the trade model does not offer any welfare implication. It removes a major blocking stone for the World Trade Organization to promote free trade

This paper unveils a serious mistake committed by Kemp (1967). His positive tariff is actually an export subsidy. The corrected Kemp model implies that the whole optimal tariff theory must have been working in the wrong direction

This paper unveils the tricks of how Kahn achieves his optimal tariff theory. When corrected, the optimal tariff turns out to be zero or negative.Apart from David Ricardo's comparative advantage, the most influential theory in the international trade study must be the optimal tariff theory (C....