Tenure Security, Investment and Productivity in Gambian Agriculture: A Generalized Probit Analysis

The determinants of investment, input use, and productivity are investigated under customary tenure in peri-urban areas of the Gambia. A structural model is specified to investigate the role of tenure security on farm investments and input use and thereby on yield. Testing of the structural form hypotheses requires simultaneous equation estimation. Containing both continuous and discrete endogenous variables, the model is estimated as a feasible generalized least squares Amemiya's generalized probit. Some of the positive relationships hypothesized between tenure security, investment, and yields are corroborated. In particular, tenure security is found to enhance long-term investments, which in turn enhance yields. Copyright 1997, Oxford University Press.