Controversy: The Source and Measurement of Technical Change Editorial Note
这篇编者按介绍了一场关于技术变革来源与生产率测量的学术争论，汇集了不同理论视角，适合对技术变革理论感兴趣的学者快速了解争论焦点。
Technological progress has always been seen as one of the most important determinants of economic growth. This controversy aims to bring together some different perspectives on this topic: the theory of the sources of technical change, the measurement of productivity, and lastly the economic historians view of the economist's view. All of the authors are leading contributors to this field, who have tried to link together theory and evidence. The first two papers consider the theory of technical changes. Vernon Ruttan's paper surveys the three main theoretical approaches to understanding the sources of technical change. The first is the notion that technical change is induced by other economic factors (factor price changes, demand, growth); the second the evolutionary approach with its Schumpeterian overtones, associated with Richard Nelson and Sydney Winter; thirdly the notion of path dependence, associated with the names of Brian Arthur and Paul David. Ruttan argues that all three of these research agendas are reaching a dead end, and that a new theory of technical change is required. Giovanni Dosi takes a more sanguine view. He believes that the current state of the art embodies an interaction between theory and evidence which points the way to a brighter future. In particular, he sees the need for an underlying and fundamental shift in perspective away from a commitment to ‘equilibrium’ to a theory of technological dynamics based on bounded rationality and evolutionary concepts.