GDP两种测算结果差异原因的实证分析

An Empirical Analysis on Differences of Two Methods for Measuring GDP

比较价格水平是用来衡量汇率法和购买力平价法测算各国GDP水平的偏差程度的指标。比较价格水平偏离越大,则说明两种方法的测算偏差越大。本研究深入探究造成两种方法测算世界各国经济规模偏差的原因,分别从汇率水平和价格水平两个角度出发,总结了市场分割、贸易壁垒等7个汇率水平造成的差异以及定价机制、经济规模等9个价格水平造成的差异。在此基础上,对以上影响因素进行综合分析,将其归纳为经济自由度指数、人均GDP、经济增长速度、人均家庭消费支出、对外开放度和汇率制度安排等6个指标变量,作为比较价格水平的解释变量。采用88个国家2000年至2003年的真实数据,实证检验各个指标变量的合理性,并确定各个指标的影响程度。最后,本研究计算出不同发展水平下相对应的比较价格水平,来描述比较价格水平的发展轨迹,从而归纳出发展中国家比较价格水平的发展趋势。

Comparative Price Level is the index for measuring the warp of GDP between the rate and the Purchasing Power Parity （PPP） . The closer to one the comparative price level is, the larger the warp will be. This paper explores the reasons why the warp exists between the two methods. Seven reasons induced by the rate were summarized, such as the division of the market, trade barrier and so on. At the same time, nine reasons induced by the difference of the price level were given, including pricing system and economical scale. Furthermore, these reasons were summarized as six factors ： economic freedom, GDP per capital, growth of the economy, house consumption per capital, the openness degree of the economy, exchange rate arrangement. These factors are regarded as independent variables, and comparative price level is the dependent variable. With data of 88 countries from 2000 to 2003, the rationality of these independent variables was checked. Finally, the research describes the development trace of comparative price level by calculation of it under corresponding development level. As a result, the trend of comparative price level was concluded for developing countries.