Ed Mansfield and the Diffusion of Innovation : An Evolutionary Connection

The purpose of this study is to summarize the work of Ed (Edwin) Mansfield, an acknowledged pioneer in the study of technological change, and its economic consequences, and to relate his contributions to the wider framework of evolutionary economic analysis.Mansfield's use of the logistic curve, one of a family of "S" curves to which scholars have turned to summarize the evolutionary dynamics of the spread of innovation, connects his work to evolutionary economics. Behind the logistic curve lies a more general logistic law describing the relative diffusion of competing innovations in a population of technologies that serve some common economic purpose.Logistic phenomena are deeply embedded in competitive evolutionary processes, but these processes do not generate a logistic curve when the diffusion data are plotted over time.The logistic law and the logistic curve must be separated conceptually, and only in special cases will the latter follow from the former. While the logistic curve is a very special case of the more general logistic law, the law itself is the signature of the evolutionary population dynamic.Mansfield's legacy is his emphasis on the connection between investment and the diffusion of innovation.This connection accounts for the diversity in utilization growth rates, as well as the fact that dynamic diversity is the fundamental evolutionary problem. (SAA)