Modern theories of trade and economic geography consider the role of product differentiation under monopolistic competition in manufacturing, under the assumption that agriculture produces homogeneous goods. By contrast, agribusiness studies examine the case of active high-productivity entrepreneurs who pursue product differentiation by creating new products. To reconcile these two contradicting views of agriculture, we examine the incidence of farm heterogeneity and product differentiation. We use microdata of Japanese farmers to estimate their total factor productivity and find that heterogeneity is relatively low in the fruit, rice, and greenhouse horticulture farming sectors, and high in the livestock and poultry sectors. We find that the degree of product differentiation is relatively high in the livestock and poultry sectors, and that elasticity of substitution in the vegetable and upland field farming sectors is around three, which is similar to the findings of earlier studies.

中文翻译：

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日本农民生产力的微观数据分析：估计农场异质性和品种间替代弹性

现代贸易和经济地理学理论在假定农业生产同质产品的情况下考虑了制造业垄断竞争下产品差异化的作用。相比之下，农业综合企业研究考察了通过创造新产品来追求产品差异化的活跃的高生产力企业家的案例。为了调和这两种相互矛盾的农业观点，我们研究了农场异质性和产品差异的发生率。我们使用日本农民的微观数据来估计他们的全要素生产率，发现水果、水稻和温室园艺农业部门的异质性相对较低，而畜禽部门的异质性较高。我们发现畜禽行业的产品差异化程度较高，