Adoption curve

The technology adoption lifecycle is a sociological model, originally developed by Joe M. Bohlen and George M. Beal in 1957 at Iowa State College. Its purpose was to track the purchase patterns of hybrid seed corn by farmers. Approximately six years later Everett Rogers broadened the use of this model in his book, Diffusion of Innovations.
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rate at which people accept and become users of a product (see diffusion curve and adopter categories).