Diffusion of Innovation

The study of the diffusion of innovation is the study of how, why, and at what rate new ideas and technology spread through cultures.This research topic began in the 1950s at the University of Chicago with funding from television producers who sought a way to measure the effectiveness of broadcast advertising. It soon became apparent that advertised products or services were "innovations" in the culture. The general result of the study was that the most influential channel of influence was not from some broadcast medium, but down a echelon of levels, from a small number of "early adopters" to a larger number of "secondary adopters", and from them to "tertiary adopters", then to "quadranary adopters", etc. There was also lateral influence within each level. Broadcast messages could reinforce the propagation from one adopter level down to the next, but lower levels are unlikely to respond until the level above them has adopted. It found that people were more likely to adopt, or even consider adopting, if people they know and respect have adopted. Imitation is the strongest influence channel. Therefore, the most effective marketing strategy is to first sell to the early adopters, then reinforce the diffusion to each successive level, but not to waste resources on trying to reach any given level before it is ready for it.
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the idea that some groups within a market are more ready and willing to adopt a new product than others and that the product is diffused through a society in waves; the groups, in order of their readiness to adopt are innovators (2.5 percent of the population), early adopters (13.5 percent), early majority (34 percent), late majority (34 percent) and laggards (16 percent).