The Illusory Diffusion of Innovation: an Examination

Innovation researchers have known for some time that it is possible for a new technology to be widely acquired but only sparsely deployed among acquiring firms. When this happens, the observed pattern of cumulative adoptions will vary depending on which event in the assimilation process (i.e., acquisition or deployment) is treated as the adoption event. Instead of mirroring one another, a widening gap—termed here an assimilation gap—will exist between the cumulative adoption curves associated with the alternatively conceived adoption events. The implications of this fact, however, have not previously been incorporated into diffusion modeling studies. When a pronounced assimilation gap exists, the use of cumulative acquisitions as the basis for diffusion modeling can present an illusory picture of the diffusion process—leading to potentially erroneous judgments by vendors and prospective adopters about the robustness of the diffusion process already observed, and the technology's future prospects. This study develops the assimilation gap concept, describes the circumstances under which assimilation gaps should be most likely, proposes techniques for their measurement and analysis, and applies these techniques in a study of three innovations in software development process technology: relational database management systems (RDBs), general purpose fourth generation languages (4GLs), and computer aided software engineering tools (CASE). Analysis based on graphical techniques showed that, as expected, CASE had a pronounced assimilation gap, while RDBs and 4GLS had more moderate gaps. Further analysis based on survival analysis techniques revealed that differences in the size of the gaps for the three technologies were statistically significant, and that each gap was large enough in absolute terms to be of practical interest. For researchers, these results suggest that the time of deployment be captured instead of, or in addition to, time of acquisition as the bases for diffusion modeling for any technology where the strong possibility of an assimilation gap exists. The results also suggest that managers be guarded about concluding, based on impressive sales data, that an innovation is necessarily destined to become widely used. (