TFP模型的研究一般基于长期观察整个国家的索洛增长模型。索洛增长模型是通过使用柯布 – 道格拉斯生产函数的要素生产率和技术提升对经济增长进行的长期分析。典型的科布道格拉斯生产函数如下所示：
Agriculture growth researches in the past have varied descriptions in connecting global market effectively with the output of domestic industry. They are generally separated into two types, which is Production Function and Export Demand Function. Even most of the variables’ selection between those two orientations are different, there are still constant elements considered by both model, such as exchange rate, economic size in international competition etc. Thus it is worth to conduct a preview summary of both kinds of articles.
Total Factor Productivity Function (TPF) is a model that assumes to describe the output by considering the productivity from input to output. Basically, those model are directed towards a static analysis to the previous data, the other trait is the analysis are mainly from microeconomic view, which import kinds of input into model and use formula to transform it to output. According to the static sight to the growth there are several useful insights that could be offered from those researches.
Basic Situation of Agriculture in China
Researches in TFP model are generally based on Solow growth model that observes the country as a whole through a long period. Solow growth model is a long run analysis of the growth of an economy through factor productivity and technological enhancement using a Cobb-Douglas like production function. A typical Cobb Douglas production function looks like:
Here, α and β represent the corresponding elasticity of labor (L) and capital (K) and A is the exogenously determined factors like technology. The sum of α and β determine the returns to scale of the production: if the sum is greater than 1, it is increasing returns to scale, equal to 1 implies constant returns to scale and less than 1 implies diminishing returns to scale. While a typical Solow model does not exclusively focus on any one sector, it is extended to use data from agriculture only to analyze the scenario of agriculture in different conditions.