This paper examines historical changes in the duration of the interval between the commercial introduction of a new product and the time when entry by later competitors begins. A priori reasons are examined why the duration of this interval in the U.S. economy may either expand or contract. Data...

This paper is an attempt to explain diffusion in the production of an innovation. Diffusion in production is defined as the increase in number of producers, or net entry, in the market for a new product. It is to be distinguished from the more familiar problem in the literature on technical...