关键词: 产品创新, 过程创机关报, 网络外部性

Abstract:

The problem of optimal control of product innovation (improving product quality) and process innovation (reducing marginal production costs) of a monopoly company producing a single product in a continuous time is discussed, and a dynamic control model under network externality conditions is established to discuss the stable equilibrium of the system and investment strategy issues related. The result shows that there exists a unique saddle equilibrium. When the sign of the change rate of investment in product innovation and process innovation is the same (opposite), the two investments are complementary (alternative). When the fixed intensity of network externality decreases, the steady-state product innovation and process innovation investment of the company increases as the product quality improves, and as the marginal production cost of the product decreases; when product quality and marginal production cost change around the steady state, the product innovation and process innovation investment are complementary. In addition, the investment in both product innovation and process innovation under the condition of maximizing social welfare is higher than the corresponding investment under the condition of maximizing the profits of the company. Although the product price under the condition of maximizing social welfare is determined by the company, the product price under this condition is still higher than that under the condition of maximizing the profit of the company.

Key words: product innovation, process innovation, network externaliy