The paper argues that, from a dynamic efficiency perspective, intersections of factor price frontiers are irrelevant to the choice of techniques. Because every change in technique involves a temporary loss or gain in both profit and per capita consumption within the transition period, its...

We analyze the role of optimal income taxation across different local labor markets. Should labor in large cities be taxed differently than in small cities? We find that a planner who needs to raise revenue and is constrained by free mobility of labor across cities does not choose equal taxes...