经济政策不确定性对进口产品的异质性影响——基于中文报纸大数据文本的实证分析

Product heterogeneous effects of economic policy uncertainty on imports:Big data context analysis based on Chinese newspapers

本文使用Baker等(2016)构建的中国经济政策不确定性指数(EPU),和基于中文报纸文本关键词搜索构造的中国经济政策不确定性指数(CEPU),运用中国2010年1月-2016年4月约5000种产品的进口月度数据,分别估计了EPU和CEPU对这些产品进口的影响,发现经济政策不确定性对于不同产品的进口影响是不同的,既有负向影响的,也有正向影响的.进一步,我们采用BEC大类分类、差异化产品和同质产品、全球贸易国家数与集中度、进口需求弹性来刻画产品的异质性,对经济不确定性对不同产品影响的差异进行了解释.我们发现当中国的经济政策不确定性增大时,资本品和运输设备相比中间投入品、差异化产品相比同质产品,进口受到的负面影响更大;需求替代弹性越小、全球进口国家数越多、全球进口国家集中度越低、全球出口国家集中度越高的产品,其产品进口的负面反应越大.此外,我们对比EPU与CEPU这两个指数在回归中的表现,CEPU指数比EPU指数的结果更为合理.

This paper uses Baker et al.(2016)to construct China's economic policy uncertainty index(EPU)and China's economic policy uncertainty index based on Chinese newspaper text keyword search(CEPU).Using monthly import data of about 5000 kinds of products in China from January 2010 to April 2016,we estimate the impact of EPU and CEPU on these products'import and find that economic policy uncertainty has different effects on imports of different products,both negative and positive.Further,we use BEC classification,differentiated products and homogeneous products,the number and concentration of countries in global trade,and the elasticity of import demand to characterize the heterogeneity of products and explain the differences in the impact of economic uncertainty on different products.We find that when the uncertainties of China's economic policy increase,capital goods and transport equipment are more negatively affected by imports than intermediate inputs and differentiated products are homogeneous products;the smaller the elasticity of demand substitution,the more countries imported globally,the lower the concentration of global importing countries,and the higher the concentration of global exporting countries,the negative reaction of product imports the bigger.In addition,we compare the performance of EPU and CEPU indices.CEPU index is more reasonable than the EPU index.