Private Contributions for Public Information : Soil Testing in Malawi

We implement a public goods experiment in Central Malawi that asks small-scale farmers to contribute to the cost of a soil test, the results of which provide public information with private value. By randomly varying the plot selected for soil testing within each village, we examine the role of soil heterogeneity and free-riding in determining contributions. Farmers contribute a considerable amount to the soil test and increase their contribution if they perceive the plot selected to be similar to their own. Higher village-level soil heterogeneity is associated with reduced free-riding, increasing the likelihood of a fair equilibrium in which farmers provide similar contributions