From Learning to Doing: Diffusion of Agricultural Innovations in Guinea-Bissau
This paper analyzes the role of social networks in the diffusion of knowledge and adoption of cultivation techniques, from trainees to the wider community, in the context of an extension project in Guinea-Bissau. In order to test for social learning, we exploit a detailed census of households and social connections across different dimensions. More precisely, we make use of a village photo directory in order to obtain a comprehensive and fully mapped social network dataset. We find evidence that agricultural information spreads across networks from project participants to non-participants, with different networks having different importance. The most relevant connection is found to be between the network of people from which individuals would ‘borrow money’. We are also able to disentangle the relative importance of weak and strong ties: in our context, weak ties are as important in the diffusion of agricultural knowledge as strong ties. Despite positive diffusion effects in knowledge, we found limited evidence of network effects in adoption behavior. Finally, using longitudinal network data, we document improvements in the network position of treated farmers over time.
I am grateful for helpful suggestions from André Moreira, Inês Vilela, Julia Seither, Paulo Santos and Pedro Vicente. I would like to thank Pedro Santos, Patrícia Maridalho and the VIDA team for their cooperation and support. I wish to acknowledge the financial support provided by European Union and Camões-Instituto da Cooperação e da Língua, through the project "Kopoti pa cudji no futuro". This work was funded by Fundação para a Ciência e a Tecnologia (UID/ECO/00124/2013 and Social Sciences DataLab, Project 22209), POR Lisboa (LISBOA-01-0145-FEDER-007722 and Social Sciences DataLab, Project 22209) and POR Norte (Social Sciences DataLab, Project 22209). I would also like to acknowledge FCT for the PhD Scholarship PD/BD/105725/2014. The views expressed herein are those of the author and do not necessarily reflect the views of the National Bureau of Economic Research.