Market penetration by entry-exit dynamics

A generic characterization of the dynamics of market penetration by technological artifacts is here formulated on the basis of entry rate and exit rate considerations. It is shown that low-order reductions lead to the biologically based logistic dynamic, which—by empirical fit—has been found to be in very good agreement with numerous specific cases. In addition to the derivational justification of the logistic for artifact market penetration, we find that but a small number of parameters are involved in these autonomous characterizations suggesting therefore that market penetration may well be reduced to a similarly small number of dominant operative processes. Some nonautonomous extensions are also discussed.     

Estimating the effectiveness of extension information systems using farm trials and subjective probabilities

A method of combining survey data and Dairy Herd Improvement Association (DHIA) records to achieve low cost farm trials is presented. Farm trials and surveys of current practices and production responses are useful to identify yield gaps between expectations predicted from experimental findings and actual field results. Different management schemes can be ranked using subjective probabilities and stochastic dominance to enhance successful implementation of research findings and to increase the feedback between researchers, extension workers, and producers. A survey of current masitis control practices and expected milk yield response is the example. Combining survey results with DHIA records allowed estimating the relationship between somatic cell counts (SCC) and milk yield. Eliciting beliefs about the relationship between SCC and milk yield showed that producers agreed with predictions from the statistical model. Subjective probabilities about SCC and mastitis control practices showed that our sample of experts and producers consistently ranked the different practices but extension agents had no consensus about the the most or least effective ones.     

Some economics of content protection

We are grateful to a perceptive referee for many constructive comments on an earlier version of this paper entitled The Economics of Content Protection: A Dual Approach. The usual disclaimer applies.     

Individual rights and organizational theory

Rights are very important concepts in everyday life. And they are especially important to participants in organizations. Yet, our theories of organization and management have largely ignored rights — stressing, instead, other concepts, such as goals, roles, etc. This article describes the historical significance of rights and their relevance in understanding social behavior. The advantages of a right-based organizational theory (versus traditional goal-based theories) are discussed.This article draws on the author's forthcoming book,A Social-Contract Theory of Organizations (University of Notre Dame Press, 1988).