“…Such a proposition is found to have empirical validity with respect to the diffusion of a number of important innovations, for instance, of hybrid corn (Ryan and Gross, 1943;Griliches, 1957) in US; of agricultural reapers and mowers in US and Canada (David,1966(David, , 1971Pomfret, 1976;Jones, 1977;Atack and Bateman, 1987;Headlee, 1991); major innovations in heavy equipment in US . Conversely, one of the empirical regularities derived from empirical research on diffusion, that the diffusion path often follows a Sigmoid path, has been consistently explained by the probit models of diffusion (Davies, 1979;Karshenas and Stoneman, 1993).…”