Externalities of R&D Expenditures

Innovation is generally recognized as a major source of economic growth. R&D investments explicitly aim at generating innovations and creating knowledge. Since knowledge has certain public good properties, positive externalities are likely to exist. In this paper, we extend well-known concepts from the input-output literature (backward multipliers) to indicate at which commodities stimuli should be targeted to enhance R&D and its positive externalities in the economy as a whole. Next, we argue that there may also be negative externalities of R&D, due to increased prices. This issue can be studied by means of forward multipliers. Both concepts are applied to the United States, 1977-90.