INNOVATION AND INDUSTRIAL DISTRICTS: A FIRST APPROACH TO THE MEASUREMENT AND DETERMINANTS OF THE I-DISTRICT EFFECT

Abstract. Why are the rates of innovation per capita in the Spanish Marshallian industrial districts higher than in the other local production systems (including the local manufacturing production systems of large firms)? We analyse an exhaustive database of patents granted in Spain between 2001 and 2006 aggregated in a panel of 806 local labour markets classified by seven typologies of local production systems. Our analysis shows that Marshallian industrial districts generate 30 % of Spanish patents and an innovative output per capita that is 47 % above the national average and 31 % larger than the manufacturing production systems of large firms. The econometric estimates of a fixed effects model confirm the existence of an Innovation-district effect (I-district) and its size. The I-district effect is mainly related to the presence of Marshallian localization economies. Palabras clave: industrial districts, innovation, external economies, district effec