Rute Martins Caeiro

Research

WORKING PAPERS

From Learning to Doing: Diffusion of Agricultural Innovations in Guinea-Bissau, [Job Market Paper] NBER Working Paper No. 26065.

This paper analyzes the pathways of technology diffusion through social networks, following the experimental introduction of new technologies in Guinea-Bissau. In the context of an agricultural extension project targeting female farmers, we document both the direct effects of this intervention and subsequent diffusion from trainees to the wider community. In order to test for social learning, we exploit a detailed census of households and social connections across different social dimensions. A distinguishing feature of our approach is the use of a village photo directory to obtain a comprehensive and fully mapped social network dataset. In our first result, we show that trainees’ knowledge and adoption rose immediately after training, remaining stable thereafter. Secondly, we show that agricultural information diffuses along social networks links from project participants to non-participants. However, these effects are heterogeneous across different types of networks, the most relevant being a farmer’s ‘financial support’. In addition, we propose a novel, intuitive characterization of social connections which allows us to disentangle the relative importance of farmers’ ‘strong’ and ‘weak’ ties. Estimates in our context highlight that weak ties play as much of a role in the knowledge diffusion as strong ties. Despite positive effects in knowledge, evidence of network impacts on actual adoption behavior is more limited. Finally, we analyze how the intervention influenced the network structure. Results indicate that, following their participation in the project, treated farmers become more central in the village social network.

PUBLICATIONS

Knowledge of Vitamin A Deficiency and Crop Adoption: Evidence from a Field Experiment in Mozambique, (joint with Pedro C. Vicente) accepted for publication at Agricultural Economics.

Appendix

Vitamin A deficiency is a widespread public health problem in Sub-Saharan Africa. This paper analyzes the impact of an intervention fighting vitamin A deficiency through the promotion of the production and consumption of orange-fleshed sweet potato (OFSP). We conducted a randomized evaluation of OFSP-related training to female farmers in Mozambique, who were also the primary caretakers of pre-school children. The treatment consisted of group and individual-level training where basic knowledge about nutrition was taught, and planting and cooking skills related specifically to OFSP were developed. We find considerable increases in nutrition-related knowledge, as well as knowledge about cooking and planting OFSP, which persist after more than a year. We also observe clear evidence of adoption of OFSP for production in the short- and medium-run, which spreads through social networks. However, we do not find clear signs of dietary improvements in our specific measures of consumption of vitamin A rich foods. Overall, our results support the view that training centered on nutrition-sensitive agricultural information can play a significant role in shaping farmers’ knowledge and crop adoption decisions.

WORK IN PROGRESS

Agricultural Innovations: The Impact on Livelihoods and Social Capital of Subsistence Farmers in Guinea Bissau (joint with Paulo Santos and Pedro Vicente).

Peer Effects on Agricultural Practices (joint with Marcel Fafchamps and Pedro Vicente).

Health insurance: Community Leaders and Social Networks (joint with Alexander Coutts, Teresa Molina and Pedro Vicente).