We examine the generalizability of internally valid estimates of causal effects in a fixed population over time when that population is subject to aggregate shocks. This temporal external validity is shown to depend upon the distribution of the aggregate shocks and the interaction between these...

We examine the impact of ambiguous and contested land rights on investment and productivity in agricultural in Akwapim, Ghana. We show that individuals who hold powerful positions in a local political hierarchy have more secure tenure rights, and that as a consequence they invest more in land...

We show that the real return to capital in Ghana’s informal sector is high. For farmers, we find annual returns ranging from 205-350% in the new technology of pineapple cultivation, and 30- 50% in well-established food crop cultivation. We also examine the relative prices of durable goods of...

The investment decisions of small-scale farmers in developing countries are conditioned by their financial environment. Binding credit market constraints and incomplete insurance can reduce investment in activities with high expected profits. We conducted several experiments in northern Ghana in...