产品替代弹性测度对贸易成本影响研究——以谷物产品为例

The Impact of product substitution elasticities on Trade Costs——An Empirical Analysis of Cereal Products

我国作为传统农业大国,谷物产品贸易规模逐年攀升,成为开展对外贸易的重要领域。在贸易开展过程中,贸易成本因素与产品的替代弹性间息息相关,影响双边谷物产品的贸易利得。为此,本文以谷物产品为研究对象,选取1992-2015年联合国粮农组织数据库中谷物产品贸易数据,实证测算并比较了异质性替代弹性与统一固定替代弹性测度对贸易成本的影响。研究结果表明：采用品种替代弹性测算的贸易成本比采用固定替代弹性的贸易成本降幅更大,两者差距为10%。另外,考虑异质性替代弹性测度的谷物贸易成本在[1.14,19.22]之间取值不等,变化幅度较大,而采用固定替代弹性的谷物贸易成本在[3.05,4.91]之间的变动。因此,考虑产品替代弹性异质性的贸易成本模型解释力更强。

The research on the measurement of trade cost is mainly focused on the perspective of national or sectoral level, only few of them focus on product trade cost and neglected heterogeneity across products. This paper uses cereal products as a case, comparing the impact differences of trade cost between the heterogeneity elasticity with the homogeneity elasticity. The research results show that the trade cost of the 1992-2015 years＇ trade cost is greater than that of the homogeneity elasticity, and the gap is 10%. In addition, the cereal trade cost considering the heterogeneity elasticity is between [1.14 and 19.22]. The homogeneity elasticity of cereal trade costs fluctuate between [3.05 and 4.91]. Therefore, the trade cost of heterogeneity instead of homogeneity elasticity measure can better reflect the reality. In the future trade cost measurement, the heterogeneity elasticity measure method can be given priority.