Multigeneration innovation diffusion and intergeneration time: A cautionary note

A recent JAMS article reported the following finding: the longer the time between the launch of two adjacent generations in the same product category, the lower the initial rate of adoption of the later generation but the higher its subsequent rate of growth. This note shows that these results could be a method artifact, since they vanish once one controls for differences in the length of the data series used to compute the initial and subsequent rates of growth. So, for the time being, it is premature to accept these intergeneration effects as genuine.