Feenstra and Ma (2008) develop a monopolistic competition model where firms choose their optimal product scope by balancing the profits from a new variety against the costs of "cannibalizing" sales of existing varieties. While more productive firms always have a higher market share, there is no...

Interest in the theoretical and empirical analysis of multi-product enterprises is growing. This paper uses newly available representative longitudinal data covering the years 1995 to 2004 to document for the first time the extent of product diversification in German manufacturing enterprises...