Much public attention and considerable controversy surround pharmaceutical marketing practices and their impact on physicians. However, views on the matter have largely been shaped by anecdotal evidence or results from analyses with insufficient controls. Making use of a dynamic fixed-effects...

We explore the extent to which R&D and advertising expenditures generate a comparative advantage that allows firms to earn supranormal profits. After controlling for unobserved firm-specific factors and the feedback between discretionary expenditures and profitability, our results suggest...

Based on data from firms in the personal computer industry, we study the effect of new product introductions on three key drivers of firm value: profit rate, profit-rate persistence, and firm size as reflected in asset growth. Consistent with our theoretical development, we find that new product...