A Critical Assessment of Supply‐Demand Models of Agricultural Trade
批判性评估了农业贸易中静态、确定性的简化供需模型，指出其忽视部门间要素流动、利润非零、饲料替代性等关键局限，并强调这些局限显著影响价格和福利预测的准确性。
Abstract We offer a critical assessment of static, deterministic, reduced form, supply‐demand (SD) models of agricultural trade. A commonly used and well‐documented model has significant limitations: no explicit treatment of factor mobility between farm and nonfarm sectors, nonzero profits in some sectors, no substitutability among feedstuffs in livestock sectors, violation of the law of one price, small marketing margins for some commodities, and incomplete coverage of the agricultural sector. Such limitations have significant impacts on the magnitude and direction of projected world price and welfare changes. We believe agricultural policy analysis should first focus on the remediation of these limitations before proceeding to more complex issues like dynamics and uncertainty.