Aid and the Supply Side: Public Investment, Export Performance, and Dutch Disease in Low-Income Countries

Contemporary policy debates on the macroeconomics of aid oftenconcentrate on short-run Dutch disease effects, ignoring thepossible supply-side impact of aid-financed public expenditure.In the simple model of aid and public expenditure presentedhere, public infrastructure generates an intertemporal productivityspillover, which may exhibit a sector-specific bias. The modelalso provides for a learning-by-doing externality, through whichtotal factor productivity in the tradable sector is an increasingfunction of past export volumes. An extended computable versionof this model is used to simulate the effect of a step increasein net aid flows. The simulations show that beyond the shortrun, when conventional demand-side Dutch disease effects arepresent, the relationship between enhanced aid flows and realexchange rates, output growth, and welfare is less straightforwardthan simple models of aid suggest. Public infrastructure investmentthat generates a productivity bias in favor of nontradable productiondelivers the largest aggregate return to aid, but at the costof a deterioration in the income distribution. Income gainsaccrue predominantly to skilled and unskilled urban households,leaving the rural poor relatively worse off. Under plausibleparameterizations of the model, the rural poor may also be worseoff in absolute terms.