On public investment, long-run growth, and the real exchange rate

This paper extends the Barro (1990) endogenous growth modelwith productive government services to a two-country world withperfect capital mobility, populated by optimising agents withuncertain lifetimes. It shows that increases in government spendingon infrastructure for the home country result in higher growthrates and a terms of trade improvement. Both these effects arereversed after a point, showing that a hump-shaped curve—similarto the Barro curve, but with different properties—canbe obtained here even with lump-sum taxes. We also examine thewelfare implications of public investment policies, and characterisethe world economy's dynamics.