产品多样化视角下中国进口贸易利益估算

Product Diversification and China's Gains From Import Variety

进口品多样化是进口国获得贸易利益的重要来源之一,而贸易数据的细分程度决定其贸易利益估算结果的客观性。本文利用2000—2011年中国与240多个国家细分的HS 8位编码双边进口贸易数据,估算了4236个进口品的替代弹性值。结果显示:我国差异化产品种类替代弹性的平均值为43.1,中位数为7.6;相比2000年,2011年消失的产品种类占比为1.4%,新增加的产品种类占比为4.3%,进口差异化产品种类的净增加程度为1.5%;实际进口价格指数比未经进口品种类变化调整前的传统进口价格指数下降1.5%;2000—2011年间,我国从进口品种增长中获取的贸易利益为2011年GDP的0.56%。研究发现,以往基于粗略贸易数据的研究结论低估了我国进口品种替代弹性值、变化程度和福利效应;为提高我国进口品种的多样化程度,需要更加注重单个新增进口品种的贸易额;为提高我国进口贸易利益,应选择部分产品作为主要增长的进口品种类。

Product diversification is an important source for a country＇s gains from import trade, while the objectivity of estimation results for the gains is determined by the degree of trade data classification. By making use of China＇s bilateral HS8 import data with more than 240 countries, this paper evaluates the elasticity of substitution for 4236 products, obtaining the average elasticity of substitution of differentiated products is 43.1 and the median is 7.6. Comparing with 2000, in 2011 disappeared product categories account for I. 4% , those newly emerged account for 4.3% , and the net growth of differentiated product categories is 1.5%. The actual import price index is 1.5% lower than the traditional one which is not adjusted with variety change and China＇s gains from import variety from 2000 to 2011 is about 0. 56 % of GDP in 2011. It is found that those studies on China＇s gains from import variety using rough trade data have underestimated the elasticity value, the degree of change and the welfare effect of import variety. Furthermore, our study shows that increasing the trade volume of new product categories should be attached more importance to improve China＇s import diversification. To improve the Chinas gains from import, some products can be selected as the focus for import variety growth.