Productivity impacts of hybrid rice seeds in Vietnam
利用越南农户十年面板数据，结合倾向得分匹配和固定效应模型，发现杂交水稻相比高产品种并无生产力优势，但存在35%的技术效率差距，表明管理技能提升的潜力。
Abstract Expanding the availability of hybrid rice varieties has been regarded as the most important measure addressing food security in developing Asian countries. The success story of hybrid rice production in China motivated the Vietnamese government to import hybrid seeds in an effort to increase rice productivity. Despite increased use of hybrid rice seeds and rising input intensity, rice productivity growth has slowed since 2006. Using a ten‐year balanced panel of households with changing adoption status, we estimate productivity impacts of hybrid rice adoption. We combine propensity score matching in adoption decisions with fixed‐effects estimators to control for heterogeneity in farming household and farmland characteristics. The frontier models are specified to allow for direct comparisons of the base productivity, factor productivity, and technical efficiency between hybrid and the current high‐yielding varieties. Our major finding is that hybrid rice varieties provide no productivity superiority over high‐yielding inbred seeds in our sample. A substantial technical efficiency gap (35%) exists in rice production, suggesting a potential benefit of improvements in management skills with the existing technology.