How Do You Measure a “Technological Revolution”?
探讨了经济学如何分析技术革命的来源和机制，以及有哪些经济指标可用于衡量其整体规模和影响，重点介绍了新古典增长理论和全要素生产率（MFP）的作用。
It is hardly news that we are in the midst of rapid economic change. The advances in infor mation and communication technology (ICT), in the life and other sciences, and their profusion of innovative products, from the newest electronic devices to the latest drugs and treatments, are ample evidence. Equally pervasive are new busi ness models in services (big box retail, online banking, on-demand media ) and the explosion in social networking and new business practices ushered in by the Internet (telework, virtual meetings, job boards ). Given the magnitude of the changes brought on by these innovations, it is useful to step back and ask: What does eco nomic analysis have to say about the sources and mechanisms of these shifts and revolutions, and what economic metrics are available to measure their overall size and impact? The received theory of economic growth is the natural candidate for this job. It came of age in the 1950s and 1960s with the neoclassi cal models and emergence of aggregate growth accounting. The latter has become the work horse of empirical macroeconomic growth analysis and the basis for official productiv ity statistics put out by the Bureau of Labor Statistics (BLS) since 1983. A technological revolution appears, in this framework, as an increase in the fruits of innovation, as measured by the shift in an aggregate production function (termed multifactor productivity or MFP ), and possibly as an increase in the aggregate saving rate, as reflected in an increased rate of capital formation. MFP is an exogenous phenomenon