Dynamically optimal R&D subsidization

Previous research on optimal R&D subsidies has focussed on the long run. This paper characterizes the optimal time path of R&D subsidization in a semi-endogenous growth model, by exploiting a recently developed numerical method. Starting from the steady state under current R&D subsidization in the US, the R&D subsidy should significantly jump upwards and then slightly decrease over time. There is a negligible loss in welfare, however, from immediately setting the R&D subsidy to its optimal long run level, compared to the case where the dynamically optimal policy is implemented.