Estimating returns to soil conservation adoption in the northern Ethiopian highlands

Land degradation in the form of soil erosion and nutrient depletion presents a threat to food security and sustainability of agricultural production in many developing countries. Governments and development agencies have invested substantial resources to promote soil conservation practices as part of an effort to improve environmental conditions and reduce poverty. However, limited rigorous empirical work has been done on the economics of soil conservation technology adoption. This article investigates the impact of stone bunds on value of crop production per hectare in low and high rainfall areas of the Ethiopian highlands using cross-sectional data from more than 900 households, with multiple plots per household. We have used modified random effects models, stochastic dominance analysis (SDA), and matching methods to ensure robustness. The parametric regression and SDA estimates are based on matched observations obtained from the nearest neighbor matching using propensity score estimates. This is important, because conventional regression and SDA estimates are obtained without ensuring that there actually exist comparable conserved and nonconserved plots on the distribution of covariates. We use matching methods, random effects, and Mundlak's approach to control selection and endogeneity bias that may arise due to correlation of unobserved heterogeneity and observed explanatory variables.
We find that the three methods tell a consistent story. Plots with stone bunds are more productive than those without such technologies in semi-arid areas but not in higher rainfall areas, apparently because the moisture conserving benefits of this technology are more beneficial in drier areas. This implies that the performance of stone bunds varies by agro-ecology type, suggesting the need for designing and implementing appropriate site-specific technologies.     

The investment opportunity set and disclosure policy choice: Some Malaysian evidence

Recently researchers have shown that certain corporate and accounting policy decisions are related to the firm's portfolio of growth opportunities or its investment opportunity set (ios). This paper augments the research by examining whether the firm's ios is also predictably related to disclosure policy decisions made by the firm. We hypothesize that because agency costs between managers and shareholders are an increasing function of the firm's growth opportunities, managers in high growth firms will be motivated to disclose information about the firm's future prospects in order to commit themselves to particular courses of action and thereby limit their future managerial discretion. Our empirical results indicate that for a sample of 67 Malaysian firms, this is supported only amongst a sample of lower growth firms.The authors are Associate Professor and lecturer, respectively, at the Department of Accountancy, Massey University, Palmerston North, New Zealand. Correspondence should be addressed to S F Cahan at the above address, e-mail: S.F.Cahan@massey.ac.nz.