We study the dynamics of usage intensity of second-generation cellular telephony over the diffusion curve. Specifically, we address two questions: First, can we draw conclusions about the underlying drivers of technology diffusion by studying usage intensity? Second, what is the effect of high...

Critical Mass is a common feature of technology diffusion processes. We develop a structural model of demand with network effects to provide a rigorous definition of critical mass as a function of installed base, price and network effects. Using data from the digital cellular telephony market,...

We study the dynamics of usage intensity of second-generation cellular telephony over the diffusion curve. Specifically, we address two questions: First, can we draw conclusions about the underlying drivers of technology diffusion by studying usage intensity? Second, what is the effect of high...

We study the effect of new product introduction on firm value. Using a unique sample on mobile phone handset introduction by 16 major handset manufacturers over 10 years, we distinguish between imitative product introduction and truly innovative product introduction. We find that while most...

Most existing empirical work on technology diffusion assumes technologies to remain constant throughout the diffusion process. However, many consumer technologies improve significantly over time. Using data on the characteristics of new mobile handsets over a ten-year period and controlling for...

We document the evolution of product innovation and features in the mobile telephone handset market. We distinguish between two types of product innovation: vertical and horizontal innovation. Using data from 1990 - 2003, we find that some characteristics have subsequently become an industry...