一种改进的地区购买力平价指数

An Improved Index for Subnational Purchasing Power Parities

研究目标:测算中国地区购买力平价,反映不同地区之间价格水平的差异。研究方法:以2016年110种代表规格品价格和居民消费权重数据为样本,采用改进的CPD-EKS两步法,测算中国31个地区PPP。研究发现:产品价格存在显著的空间相关性,传统计量方法下估计的PPP结果可能有偏;在位置邻接性、距离远近、经济发展水平和经济开放度等诸多影响中国地区间价格差异的因素中,距离是现阶段地区价格产生空间关联效应的更显著因素;价格结构和经济结构的地区间差异对地区PPP会产生显著影响,采用国际通行计算方法可能会低估价格水平;中国地区PPP存在明显的地区差异性,大致呈现东部地区价格最高、西部地区次之、中部地区和东北地区价格相对最低的分布格局。研究创新:提出了考虑产品价格关联性的空间CPD模型和以拉氏指数与派氏指数方差加权的EKS-Fisher*方法,构建改进的CPD-EKS两步估算法。研究价值:改进了地区购买力平价估算方法,发展了空间价格指数理论。

Research Objectives:This paper intends to estimate the subnational purchasing power parities(PPPs)of China and reflect the price difference across regions.Research Methods:With a sample of prices for 110 representative specifications in 2016 and consumption weight data of households,this study calculated the subnational PPPs of 31 provincial regions of China using an improved CPD-EKS two-stage method.Research Findings:The results show that the price data has significant spatial correlation,so the subnational PPPs estimated by the classic methods may be biased.Among the factors that affect the price differences between regions,such as position adjacent,the level of economic development and economic openness,distance is a more significant influence factor at present.Different price structures and economic structures between regions have a significant impact on spatial price,so using the traditional methods may underestimate the price level.There is obvious regional differences for China's spatial price indices,the price distribution pattern of which is such that the highest values are in the eastern region,the second highest ones are in the western region,and the central region and the northeastern region have the relatively lowest price.Research Innovations:Based on the theory of spatial price index,this paper presents a new CPD-EKS two-stage method,which includes a spatial CPD model incorporating product price correlation and an EKS-Fisher*method weighted by the variance ratio of the Laspeyres price index and the Paasche price index as the weight of the Fisher index.Research Value:This paper improved the method to estimate the subnational PPPs and developed the theory of spatial price index.