This paper studies the innovation strategies of multi-product firms in industries with different scope for product differentiation. In a simple model of multi-product firms, we show that returns to product versus process innovation are industry-specific. Demand and cost linkages induce a natural...

The geography of innovation describes the importance of proximity and location to innovative activity. As part of what has been termed the new economic geography, this area of research is less than 20 years old, and is now developed sufficiently so that the discussion can be organized around...

The Internet plays a growing role in the economy. This paper extrapolates this trend and analyses a world where most transactions take place in "cyberspace". We ask the following question: how does the design of the search engine affect the incentives to innovate and the economy’s long run...