中间投入的关联性及经济增长方式的国际比较

作为一种资本,中间投入在生产过程中有着不可忽略的重要作用.中间投入系数大小则反映了一个国家的经济增长方式类型.目前主流经济增长理论仅仅考虑增加值生产函数,而非总产出生产函数,因此忽视了中间投入在生产过程,乃至评价经济效率中的作用.本文从统计特征,基本模型和实证检验基本范式研究了主题.从统计特征角度,中国的中间投入系数明显高于美日等发达国家,单位GDP能耗远高于世界平均水平,显示出了中国粗放型增长的特征.在基本模型上,本文通过理论推导、数值模拟得出结论:一国的经济增长方式主要与中间投入替代弹性、增加值率、技术水平等参数有关.具体表现在:首先,中间投入与最初投入之间的关联性表现为替代关系而非互补关系;其次,经济增长速度呈现出与中间投入替代弹性大小反向关系,中间投入替代弹性越大经济增长速度越慢,反之亦然;最后,均衡人均产出水平呈现出随着增加值率的增大先增大后减小的倒U形态,换言之,一国在其他条件不变的情况下,存在一个最优的增加值率.在实证分析上,本文通过对中国、美国、日本、巴西四国的实证检验发现,一方面,不同发展阶段的国家的中间投入的替代弹性不同,且各自具有一定的独立性,美日等发达国家的替代弹性明显高于中国和巴西等发展中国家;另一方面,各国的实际增加值率与最优增加值率之间存在着偏差,且发达国家的偏差要小于发展中国家,中国和巴西存在的偏差要远大于发达的美国和日本.

Study on intermediate inputs linkage and comparison of economic growth mode

As a kind of capital, intermediate inputs play an important role that cannot be ignored in the process of production. Their coefficient size reflects a country's economic growth mode. Current mainstream economic growth theories only consider the value added production function, rather than gross output production function, thus ignoring the role of intermediate inputs in the production process and the evaluation of economic efficiency. This paper is based on the statistical characteristics, basic model and empirical test of the basic paradigm. From the perspective of statistical characteristics, China's intermediate inputs coefficients are significantly higher than that of U.S. and Japan and other developed countries. The energy consumption per unit GDP is far over the world average level, which shows that the characteristic of China's economic growth is of extensive growth mode. By using theoretical derivation and numerical simulation, this paper has drawn the conclusion that a country's economic growth mode is related to the intermediate inputs elasticity of substitution, value added rate (VAR), technical level, and some other parameters. Firstly, there exists substitution rather than complementary linkage between primary investment and intermediate inputs. Secondly, economic growth rate shows negative correlation with the size of the elasticity of substitution of intermediate inputs, and the greater, the slower, and vice versa. Thirdly, inverted U shape shows that with the increase of intermediate inputs rate, the equilibrium output increases first and then decreased. In other words, there exists an optimal VAR. In the empirical analysis by using data of China, U.S., Japan and Brazil, the paper proves that there are obvious differences in the elasticity of substitution of intermediate inputs among different countries at their different stages during development. On the one hand, there is a different elasticity of substitution at different stage for a country with a certain independence, and the elasticity of substitution of U.S. is much higher than that of China. On the other hand, there is deviation between the actual VAR and the optimal VAR among these countries, and the deviation of China and Brazil is much larger than that of U.S. and Japan.