The presumption that R&D is a key driver of economic growth is difficult to reconcile with empirical evidence. For example, in most studies, which identify technical change with total factor productivity (TFP), the link between TFP and measures of knowledge is found to be weak.
This paper shows that a reconciliation may be possible in a model where R&D contributes to growth through investment-specific technical change. Such a model predicts that the empirical link between knowledge and productivty would be weak even if the generation of knowledge is the predominant factor of economic growth. The paper also shows that estimates of the production function for knowledge using patent data may be biased.
