Theories of the fertility transition now routinely reserve a place for diffusion effects. Two fundamental behavioral mechanisms account for such effects: social learning and social influence. Social learning refers to the acquisition of information from others. The information might have to do with a new technology or with the health, social, and economic consequences of decisions. In the case of fertility, individuals might learn from others about the availability of a new contraceptive, or about health side effects of certain contraceptives, or about the apparent gains and losses from having fewer children and investing in their schooling. Social influence refers to the power that individuals exercise over each other through authority, deference, and social conformity pressures. Our aim in this paper is threefold: to assemble the disparate concepts of the diffusion perspective into a coherent whole; to review the literature in and outside demography in the light of these concepts; and to present simulations and new data on the role of social networks, through which social learning takes place and social influence is exercised. Throughout the paper, we illustrate the issues with applications to Ghana, one of the sites being explored in new longitudinal research.
Montgomery, Mark R. and John B. Casterline. 1998. "Social networks and the diffusion of fertility control," Policy Research Division Working Paper no. 119. New York: Population Council.