Technological Specialization and Variety in Urban Invention

Abstract

O HUallachain B. and Lee D.-S. Technological specialization and variety in urban invention, Regional Studies. Urban economic theory distinguishes between knowledge spillovers that occur within specializations and those that cross technologies. Empirical analysis has sought to gauge their relative strength, but the results are inconclusive. Metropolitan specialization and variety at different aggregation levels of a US patent classification system are assessed using Theil's relative entropy index. The results show that specialization and variety are not competing features of urban technological structure; cities can have both. The invention rate positively associates with specialization in diverse technologies. The cross-fertilization of ideas among skilled professionals with different expertise and the interaction between specialists of narrow fields of knowledge are both important in technological advance. The most inventive cities have deep specializations in different technologies. The results also show significant spatial dependence in technological specialization/variety and in invention rates. [image omitted] O hUallachain B. et Lee D.-S. La specialisation et la diversite technologiques dans l'invention urbaine, Regional Studies. La theorie economique urbaine distingue entre les retombees de la connaissance dues a la specialisation et celles qui recouvrent les technologies. L'analyse empirique a cherche a estimer leur importance relative, mais les resultats s'averent peu concluants. Employant l'indice entropique relative de Theil, on evalue la specialisation et la diversite metropolitaines a divers niveaux d'agregation du classement des brevets aux E-U. Les resultats laissent voir que la specialisation et la diversite ne se rivalisent pas dans la structure technologique urbaine; les grandes villes peuvent se doter des deux. Le taux d'invention est en etroite correlation avec la specialisation dans diverses technologies. La synergie des professionnels qualifies, dont les competences varient, et l'interaction entre les specialistes, dont les domaines de competences sont bien delimites, sont importantes, toutes les deux, au progres technologique. Les grandes villes les plus inventives ont des specialisations approfondies dans diverses technologies. Les resultats montrent aussi une dependance geographique vis-a-vis de la specialisation/diversite technologiques et des taux d'invention. Invention Specialisation Diversite Effets externes urbains Brevets O hUallachain B. und Lee D.-S. Technologische Spezialisierung und Vielfalt bei urbanen Erfindungen, Regional Studies. In der Theorie der urbanen Okonomie unterscheidet man zwischen Wissensubertragungen, die innerhalb einer Spezialisierung erfolgen, und Wissensubertragungen, die technologieubergreifend stattfinden. Es wurde versucht, die relative Starke dieser Wissens-ubertragungen durch empirische Analysen zu ermitteln, was jedoch zu keinen schlussigen Ergebnissen fuhrte. Mit Hilfe des Theilschen relativen Entropieindexes untersuchen wir die metropolitane Spezialis...

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Inventive Megaregions of the United States: Technological Composition and Location

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