"The author tests how the local economic structure-measured by a region's sector specialization, competition, and diversity-affects the technological growth of manufacturing sectors. Most of the empirical literature on this topic assumes that in the long run more productive regions will attract...

"In infrastructure, the possibility of a positive relationship between operators' profitability and the degree of concentration is a major political issue in view of the wide diversity of feelings about the potential role of the private sector. This is particularly important because of (1) the...