Cities, knowledge and innovation

Based on an overview of historical conceptualizations of knowledge, knowledge diffusion and innovation in cities, we make a plea for conceptual and methodological renewals in research to address current impasses. Firstly, we conclude that analyses using knowledge production functions to capture knowledge flows do not, as of yet, provide full insight into the generation and transfer of different kinds of knowledge. Only recently are various conceptualizations of distance and knowledge transmission channels able to address the heterogeneity of the actors and processes involved in capturing the respective role of cities in knowledge creation. Research should more explicitly focus on the transfer mechanisms of knowledge diffusion. Secondly, our plea for a better embedding of the mechanisms that create and diffuse knowledge is extended to the current discourse on agglomeration externalities in which new conceptual and methodological views appear to be needed as well. In particular, evolutionary economic geographical concepts are promising in explaining the innovative behavior of growing firms and organizations in cities, carefully addressing the heterogeneity of the actors involved, spatial scale, selection and survival as well as time and path dependency. Econometric identification strategies help achieving these goals.