Risks and returns from soil conservation: evidence from low‐income farms in the Philippines
研究了菲律宾山坡农场采用等高绿篱对玉米产量的影响，发现可提高产量最多15%，但风险降低效果有限，仅对高风险厌恶者具有优势。
Abstract This paper examines risks and returns associated with soil conservation on hillside farms in the Philippines. Stochastic efficiency analysis is combined with a heteroskedastic regression model to assess the impacts of contour hedgerows on low‐income corn farms. Regression analysis indicates that, over time, contour hedgerows can improve yields up to 15% compared with conventional practices. The analysis also provides weak support tor a hypothesis that hedgerows are variance reducing. However, results show that the reduction in yield variability afforded by hedgerows is modest, and that yield variability may increase by as much as 5% as hedgerow intensity rises. Tests for stochastic dominance show that, compared with the conventional tillage system, hedgerows do not constitute an unambiguously dominant production strategy. Stochastic elticiency with respect to a function is used to identify a range lor the coefficient ol relative risk aversion within which hedgerows dominate conventional tillage. Results suggest this range would be rather high; hedgerows dominate the conventional cropping strategy only lor decision‐makers with relative risk aversion coefficients in the range 3‐5.5. Implications for soil conservation adoption in low‐income settings are discussed.