How much should governments subsidize the development of new clean technologies? We use patent citation data to investigate the relative intensity of knowledge spillovers in clean and dirty technologies in two technological fields: energy production and transportation. We introduce a new...

This paper investigates the economic impact of the government's proposed new UK R&D tax credit. We measure the benefit of the credit by the effect on value added in the short and long?run. This is simulated from existing econometric estimates of the tax?price elasticity of R&D and the effect of...