The Diffusion of Innovations: A Methodological Reappraisal
指出传统扩散研究依赖特定分布（如逻辑分布）导致可比性和解释问题，提出用基尼期望平均差衡量扩散速度，并讨论截断过程、组间比较等，以CT扫描仪扩散为例说明。
Studies of diffusion have traditionally relied on specific distributions-primarily the logistic- to characterize and estimate those processes.We argue here that such approach gives rise to serious problems of comparability and interpretation, and may result in large biases inthe estimates of the parameters of interest. We propose instead the Gini's expected mean differenceas ameasure of diffusion speed, discuss its advantages over the traditional approach, and tackle with it the problems of truncated processes, inter-group comparisons, and related issues. We also elaborateon the use of the hazardrate, and suggest some possible extensions. The diffusion of CT scanners is presented as an illustration.