Spatial Relationships in Choosing to Conserve Soil in Smallholder Rubber Farming

Soil conservation is one pivotal activity in Good Agricultural Practices. Thus, diffusing such activities among farming community is prudent. In spite of the fact that soil conservation choices are believed to be highly correlated in space, this aspect is seldom addressed in the literature. We take up this issue and attempt to model soil conservation choices of a sample of rubber farmers in Sri Lanka. Our focus is on one critical role in diffusion: the possibilities of interaction among farmers. Keeping in line with the previous literature, we deduce that individual farmers’ decisions are often influenced by the choices and opinions of others in their immediate environment. The difficulty in capturing this effect is circumvented by estimating a spatial correlation coefficient in a spatial auto-regression framework. The dichotomous nature of the dependent variable forces us to utilize a ‘Spatial Autoregressive Probit Model’. We employ recent developments in Bayesian econometric techniques in analysis. Results show a significant spatial correlation revealing a clear indication of a ‘neighbourhood effect’