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...

I develop a structural demand model for mobile telephone service, which facilitates the identification of network effects and compatibility between networks. Network effects are measured by the dependence of consumer willingness to pay on the installed base of subscribers. Compatibility is...