Public Research Spending in an Endogenous Growth Model

This study constructs a variety expansion growth model with public research spending, in which public researchers raise the productivity of private R&D. We show that the rela- tionship between public research spending and the growth rate follows an inverted U-shape. This is because public research spending increases private R&D productivity, but crowds out labor input to private R&D. It is also shown that the welfare-maximizing level of pub- lic research spending is below the growth-maximizing level. With regards to tax policy, a zero-proffit tax maximizes both growth and welfare. Finally, the study analyzes the stability of the steady state, showing that the equilibrium is indeterminate when the government fs revenue source depends on asset income tax.