R&D incentives in compatible networks

Network externalities describe the phenomenon that a good becomes more valuable to each user the more other consumers use the same or a compatible troduct. Whereas most of the recent literature on network effects has focused on the adoption of products, this paper shows that network externalities can have important feedback effects on the incentives to carry out R&D and develop new products. Even if the products are compatible, network effects can lead to strategic overinvestment or underinvestment. The firms' R&D decisions are compared with the socially optimal ones.