How Might Shadow Price Restrictions Reduce Technical Efficiency? Evidence from a Restricted DEA Analysis of Coffee Farms in Vietnam
利用越南小农咖啡农场数据，通过投入导向DEA测量技术效率，并分析对化学投入品影子价格的潜在限制如何影响整体效率，发现农药和除草剂的使用对效率贡献较小，限制其影子价格不会显著改变短期效率模式。
Abstract We use data from smallholder coffee farms in Vietnam to measure the technical efficiency of coffee producers, and the degree to which potential restrictions on the shadow prices of chemical inputs might reduce overall efficiency among these farmers. Using input‐oriented data envelopment analysis (DEA) we find the use of pesticide and herbicide accounts for a relatively small proportion of overall technical efficiency in the sample. We place restrictions on input shadow prices and show that restricting their importance does not dramatically alter patterns or measures of short‐run efficiency.