The Welfare Analysis of Product Innovations, with an Application to Computed Tomography Scanners
提出用福利增益衡量产品创新大小的方法，以CT扫描仪为例，通过离散选择模型估计创新带来的社会收益，并计算研发的社会回报率。
This paper puts forward a methodology for the measurement of product innovations using a value metric, that is, equating the "magnitude" of innovations with the welfare gains they generate. This research design is applied to the case of computed tomography scanners, a revolutionary innovation in medical technology. The econometric procedure centers on the estimation of a discrete choice model (the nested multinomial logit), which yields the parameters of a utility function defined over the changing quality dimensions of the innovative product. The estimated flow of social gains from innovation is used to compute a social rate of return to R&D, to explore the interrelation between innovation and diffusion, and to trace the time profile of benefits. Copyright 1989 by University of Chicago Press.