We empirically study the dynamics of R&D productivity by firm size over an industry's life cycle. To do this, we examine the relationship between R&D expenditures, firm size, and new product introductions at the firm level in the personal computer industry. In general, we find the following. (1)...

Traditional models of consumer choice assume consumers are aware of all products for sale. This assumption is questionable, especially when applied to markets characterized by a high degree of change, such as the personal computer (PC) industry. I present an empirical discrete-choice model of...